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In both the SW (S Europe, Mediterranean) and SE (China) parts of its range, small-leaved forms of Hypericum perforatum evolved, and both have been named var. microphyllum (respectively by Candolle in 1815 and H. Léveillé in 1908). This more southern Chinese form (var. confertiflorum Debeaux), which intergrades morphologically with the larger-leaved more northern Chinese form, has small, narrow leaves, with dense, smallish partial inflorescences remaining distinct on elongate, widely ascending branches.
Hypericum perforatum has been subdivided into four subspecies, of which two occur in China.
Field observations [20,154,189] and laboratory tests [154] suggest that fire stimulates germination in St Johnswort seed, although it is unclear how fire severity and season of burning may affect germination response in St Johnswort.
In fall 1996, more than 1,000 acres (400 ha) of land planted to hard fescue (Festuca trachyphylla), tall wheatgrass (Thinopyrum ponticum), and alfalfa (Medicago sativa) were burned under prescription at the Kilby Ranch in Oregon. Before the burn, isolated patches of St Johnswort occurred around the perimeter of the ranch, with the largest patches south of the burn area. Within 7 months of the fire, immature St Johnswort plants (presumably seedlings, although this is not clearly stated) established across the burn area. The following season (1998), St Johnswort plants had matured and the St Johnswort infestation was very dense. By the 3rd postfire year (1999), St Johnswort had spread beyond the boundary of the burn area. The author suggests that an extensive St Johnswort seed bank was present and stimulated to germinate by the fire [189].
Similarly, a rangeland site was burned twice under prescription in California in October of 1926 and 1927 in an effort to control St Johnswort. The fire completely consumed St Johnswort crowns, and apparently stimulated germination in St Johnswort seed. The authors describe large numbers of St Johnswort seedlings where the fire had been "very hot." Timing of seedling emergence relative to time of burning is not given, nor do the authors indicate how it was determined that St Johnswort plants were seedlings and not root sprouts. The authors do indicate that a temperature of 260 °F (127 °C) was recorded at 0.25 inch (0.6 cm) below the soil surface in selected localities during the field burning operation, but they do not describe how this was measured, or any other temperatures recorded during the burn. Based on their observations, the authors conducted laboratory experiments to test the effects of various heat treatments on St Johnswort seed. An oven was used to expose St Johnswort seeds to 212 °F (100 °C) for 5, 15, 30, and 60 minutes; or to 260 °F (127 °C) for periods of 1 to 5 minutes. Seeds were then placed in sterilized sand and germinated in the greenhouse. The unheated control seed lots had the lowest germination rate at 44%, while seed lots exposed to 212 °F (100 °C) for 5, 15, 30, and 60 minutes had germination rates of 52%, 63%, 81%, and 75%, respectively. The germination rates of seed exposed to 260 °F (127 °C) were not given, although the authors state, "even at this temperature the seed gave a distinctly higher percentage of germination than did the untreated seeds" [154].
It is unclear whether germination of St Johnswort seed after fire is a function of heat stimulation of germination or of reduction in plant cover that allows for seedling emergence. For example, Greiling and Kichanan [71] found that St Johnswort seedling emergence was 100 times higher (p<0.01) when plant neighbors (little bluestem and old field species) were removed.
According to Agee [1], severe burning associated with log corridors in disturbed Oregon white oak woodlands provides favorable sites for many nonnative species such as St Johnswort, common velvetgrass (Holcus lanatus), and tansy ragwort. It is unclear whether the author refers to seedlings or to sprouts from established roots or root crowns, and what this observation is based on.
Variation in St Johnswort response to fire may be affected by plant community type, fire
size, fire severity and/or season of burning.
A study from New South Wales, Australia, suggests that fire severity, as
influenced by plant community type and associated fuel loads, may affect St Johnswort's
response to fire [20]. During the course of monitoring populations of biological
control insects in a native forest in southeastern New South Wales, a monitoring site was burned under
prescription in an effort to
reduce risk of major wildfires. Briese [20] examined
the effects of these fuel reduction burns on St Johnswort populations and populations of
associated biological control insects at this site.
The study site included areas with 2 distinct plant communities: an area of
open woodland dominated by eucalyptus species (Eucalyptus pauciflora and
E. stellulata) and an
area in an adjacent clearing. Before
burning, ground cover consisted of perennial grasses and various forbs
including St Johnswort. In the open area total ground cover was 50% to 70%, with 12% to 36%
St Johnswort. In the timbered area, total ground cover was 22% to 44% total with 12% to 24%
St Johnswort. The site was burned in spring
(September) 1982. Details of the fire were not
given; however, fire intensity (severity) was estimated from the percentage of
ground cover consumed, mortality of marked St Johnswort plants, and height of crown scorch
in the timbered area. In the open area,
ground cover was reduced 59% ± 11%, with 9% mortality of
St Johnswort
crowns. St Johnswort cover returned to prefire levels (12% to 36%) rapidly in the open
area, with a slight increase
in crown density within months of the fire. In the timbered area, ground cover
was reduced 100%, with 64% St Johnswort crown mortality. St Johnswort recovered more slowly in the timbered
area than in the open area, although it recovered more rapidly than associated
vegetation, mainly by growth from surviving roots. By summer (January) 1984, St
Johnswort
had reached 65% cover in the timbered area, mainly due to enhanced
growth of individual plants rather than an increase in crown density. A similar, but less extreme increase
(to about 45% cover) of St Johnswort was seen
in the open plots. The net result was a very large increase in the production of
St Johnswort flowering stems and seed in both areas in the summer of 1983/1984 [20].
Germination of St Johnswort seeds in the 1st postfire season was higher than average, but
contributed little to plant recovery. Postfire growth of St Johnswort was mainly from surviving roots,
whereas associated grasses and herbs
reestablished from seeds that did
not germinate until the following autumn. A regression of vegetative
regeneration against the proportion of original crown surviving the fire
suggests that fire can stimulate regrowth in surviving rootstocks. When damage
is light, as in the open plots, this can lead to regeneration that is greater
than the replacement rate, resulting in an increase in the proportion of crowns
originating from roots after the fire (from 78.3% ± 2.8% to 91.6%
± 2.1% in the
open area and from 82.7% ± 4.8% to 93.8%
± 2.4% in the timbered
area, p<0.05 in both cases). In the severely burned timbered plots, regeneration did
not equal replacement, though growth of individual plants was greatly
enhanced. The response of St Johnswort and of introduced biocontrol insects to increased
soil fertility following fire is important to postfire population dynamics of
both (see Fire interactions with other control methods) [20].
Results presented by Hooker and Tisdale [92] following
prescribed burning on a seral brush community in the Lochsa River area in
northern Idaho suggest a somewhat different relationship of St Johnswort recovery relative to fire severity.
The authors state that St Johnswort "increased following low intensity burning but did not
benefit when the treatment was more intense." However, plant recovery was only
measured for 1 season following burning, and the data upon which this conclusion
was based were not provided. Surface soil temperatures were measured in this
study using pyrometers, and sites with highest recorded temperatures supported
dense stand of old brush (various shrubs) and bracken fern. Bracken fern
recovered rapidly following fire and grew in dense stands, possibly explaining
why St Johnswort did not recover as well on high
severity sites [92].
Season of burning may also affect St Johnswort response. A 2nd
prescribed fire was conducted in the New South Wales study area (described
above) in fall (March) 1986. In the open area, ground cover was reduced 96% +
2%, while ground cover was reduced 85% + 9% in the timbered area by the
fall burn. There was massive germination of herbs and grasses, including St
Johnswort,
following the fall burn. Because St Johnswort seedlings are
poor competitors, the native grass and forb component remained dominant in both
areas in 1987, despite some recovery of
mature St Johnswort plants [20].
Other fire studies where St Johnswort occurred in the plant community but was
not the focus of the study provide no clear picture of St Johnswort's response to fire.
Results from studies in Oregon, Washington, and Idaho are presented to demonstrate the
variability of this response. A native wetland prairie site in Willamette
Valley, Oregon, dominated by tufted hairgrass and invaded by several woody
species, was treated to remove woody species by burning, hand-removal, or mowing.
St Johnswort was present before treatments were imposed. Where plots were burned or woody plants removed by hand,
St Johnswort cover was also
reduced. The authors speculate that this reduction may have been due to
increased abundance of insect herbivores with increased light
[40]. A moderate-severity fire in a snowberry-rose association in northeastern Oregon
had little effect on St Johnswort cover. Prefire cover of St Johnswort averaged 1% in a stock
exclosure and 10% in a game exclosure. No St Johnswort was found 1 year after fire, and
St Johnswort cover was 3% in the stock exclosure and 9% in the game exclosure 5 years after fire [96].
Thickets of scotchbroom in prairies and oak woodlands in Ft. Lewis, Washington,
were burned under prescription in fall (September) 1994 to try to reduce
frequency and density of scotchbroom. Average prefire cover of St Johnswort was 1.1%, and
postfire cover, recorded in May 1995, was 1.9%. These results indicate no
significant (p<0.05) change in St Johnswort cover; however, the duration of the study is
insufficient to be conclusive. Additionally, no data are given for St Johnswort response to spring burning
in the same study (some fire details are given) [180]. Brush covered slopes in northern Idaho were burned in May 1975,
and seeded with several nonnative herbaceous species in May 1975 in an effort to
improve winter/spring forage for elk. Plant frequency and green weight
production were measured for 4 growing seasons following burning. St Johnswort "occurred on all 3 study areas
and did not show any obvious changes following any treatment" (some fire
details are given) [115].
St Johnswort is native to Europe, western Asia, and North Africa, and is now widely distributed through the temperate areas of the world including parts of South America, India, New Zealand, Australia, and South Africa. St Johnswort is considered a weed in much of its native range, particularly in Turkey, Italy, France, Hungary, and Sweden, mainly in poor pastures, neglected areas, and occasionally in crops [139]. Its wide distribution may in part be attributed to its cultivation as a medicinal or garden plant [45].
In Canada, St Johnswort is found mostly in the eastern provinces and British Columbia, and is absent in the prairie region [45,99]. In the U.S., St Johnswort is distributed from Minnesota south to central Texas, east to the Atlantic Coast, and west to the northern Pacific coaSt Plants database provides a state distribution map of St Johnswort.
St Johnswort was likely introduced to North America multiple times [121]. According to Sampson and Parker [154], who review its history of introduction in North America, the 1st recorded occurrence of St Johnswort in North America was from Pennsylvania in 1793. St Johnswort was established in many western states by the early 1900s. The majority of St Johnswort infestations at that time occurred in 2 regions: the western coastal region, including northern California, western Oregon, and western Washington; and the Interior West, including northeastern Oregon, eastern Washington, northern Idaho, and northwestern Montana [78,142]. By 1945, St Johnswort infested about 2.5 million acres (1 million ha) in California, and about 1.2 million acres (500,000 ha) in Idaho, Oregon, and Washington [177]. In central North America, St Johnswort never reached the densities observed in the West, likely because cropland habitat is not ideal for St Johnswort [121].
St Johnswort population levels were dramatically reduced following a successful biological control program begun more than 50 years ago in heavily infested regions in the western U.S. [93,177]. According to Piper [143], in other areas many St Johnswort populations are still increasing in size, even where biological control organisms are present, while others have remained relatively static. A reliable published estimate of the amount of land presently infested by St Johnswort is not available [143]. Additionally, whether biocontrol in the West is currently as efficacious as it was initially is not well documented [121].
The following lists include vegetation types in which St Johnswort is known to be or thought to be potentially invasive, based on reported occurrence and biological tolerances to site conditions. Some habitats that may be invaded by St Johnswort following soil and/or vegetation disturbances are also included. Precise distribution information is limited, especially in central and eastern North America; therefore, these lists may not be exhaustive.
Fire adaptations: Mature St Johnswort plants have deep, extensive perennial root systems, and reproduce vegetatively from lateral roots and root crowns. Vegetative propagation in St Johnswort seems to be stimulated by grazing, fire, and defoliation [41,178] (see Asexual regeneration). This adaptation allows St Johnswort to survive even severe fire, depending on site conditions. A protective tissue of suberized cells called polyderm has been described on St Johnswort roots (Esau 1960, as cited by [45]). It is unclear whether this tissue might provide protection from heat.
St Johnswort also establishes from seed, and St Johnswort seed is commonly found in soil seed banks. Estimates of 6 to 30 years or more have been suggested for longevity of viable St Johnswort seed in soil seed banks (see Seed banking). Additionally, heat seems to stimulate germination in St Johnswort seed, and researchers have observed flushes of St Johnswort seedlings following fire [20,154,189]. See Discussion and Qualification of Fire Effect for more details.
FIRE REGIMES: St Johnswort occurs in a wide variety of ecosystems in North America which represent a wide range of historic FIRE REGIMES. In many areas where St Johnswort occurs, historic FIRE REGIMES have been dramatically altered due to fire exclusion and to massive disturbances associated with human settlement. The historic FIRE REGIMES of native communities in which St Johnswort sometimes occurs range from low frequency, high-severity stand replacing fires in wet forest types; to high frequency, high-severity fires in prairie grasslands; to high frequency, low-severity fires in open ponderosa pine forests. St Johnswort did not occur in these communities at the time in which historic FIRE REGIMES were functioning, but has established since fire exclusion and habitat alteration began. It is unclear how historic FIRE REGIMES might affect St Johnswort populations.
St Johnswort also occurs in areas where annual grasses such as cheatgrass are dominant. Fire regime change due to invasion of annual grasses is well documented [23,47] (see cheatgrass in FEIS). Cheatgrass expansion has dramatically changed FIRE REGIMES and plant communities over vast areas of western rangelands by changing the fuel properties of invaded communities (sensu [23]) and thus creating an environment where fires are easily ignited, spread rapidly, cover large areas, and occur frequently [204]. Short fire return intervals in cheatgrass-dominated communities (<10 years [141,194]) may favor St Johnswort, with its large root system, ability to sprout after injury, and seed germination stimulated by heat. More research and field observations are needed to understand how St Johnswort responds to the current fire ecology of these areas.
It is also unclear how the presence of St Johnswort might affect FIRE REGIMES in invaded communities. In general, in ecosystems where St Johnswort replaces plants similar to itself (in terms of fuel characteristics), St Johnswort may alter fire intensity or slightly modify an existing fire regime. However, if St Johnswort is qualitatively unique to the invaded ecosystem, it has the potential to completely alter the fire regime (sensu [23,47]). Two authors suggest that presence of dry senescent stems of St Johnswort create a fire hazard in forest areas in California [154] and Australia [139]. It is unclear whether these assertions are based on conjecture or on observations made by the authors. No examples of historic FIRE REGIMES altered by St Johnswort invasion are described in the available literature.
The following list provides fire return intervals for plant communities and ecosystems where St Johnswort may be important. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".
Community or Ecosystem Dominant Species Fire Return Interval Range (years) silver fir-Douglas-fir Abies amabilis-Pseudotsuga menziesii var. menziesii > 200 grand fir Abies grandis 35-200 [3] maple-beech-birch Acer-Fagus-Betula > 1,000 silver maple-American elm Acer saccharinum-Ulmus americana < 35 to 200 sugar maple Acer saccharum > 1,000 sugar maple-basswood Acer saccharum-Tilia americana > 1,000 [188] California chaparral Adenostoma and/or Arctostaphylos spp. 140] bluestem prairie Andropogon gerardii var. gerardii-Schizachyrium scoparium 106,140] silver sagebrush steppe Artemisia cana 5-45 [88,144,201] sagebrush steppe Artemisia tridentata/Pseudoroegneria spicata 20-70 [140] basin big sagebrush Artemisia tridentata var. tridentata 12-43 [155] mountain big sagebrush Artemisia tridentata var. vaseyana 15-40 [5,27,126] Wyoming big sagebrush Artemisia tridentata var. wyomingensis 10-70 (40**) [186,204] coastal sagebrush Artemisia californica 140] plains grasslands Bouteloua spp. 140,201] cheatgrass Bromus tectorum 141,194] California montane chaparral Ceanothus and/or Arctostaphylos spp. 50-100 [140] sugarberry-America elm-green ash Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica 188] curlleaf mountain-mahogany* Cercocarpus ledifolius 13-1,000 [7,156] northern cordgrass prairie Distichlis spicata-Spartina spp. 1-3 [140] beech-sugar maple Fagus spp.-Acer saccharum > 1,000 [188] California steppe Festuca-Danthonia spp. 140,167] black ash Fraxinus nigra 188] juniper-oak savanna Juniperus ashei-Quercus virginiana < 35 western juniper Juniperus occidentalis 20-70 Rocky Mountain juniper Juniperus scopulorum 140] cedar glades Juniperus virginiana 3-22 [74,140] western larch Larix occidentalis 25-350 [4,11,50] wheatgrass plains grasslands Pascopyrum smithii 140,144,201] Great Lakes spruce-fir Picea-Abies spp. 35 to > 200 [53] pine-cypress forest Pinus-Cupressus spp. 3] pinyon-juniper Pinus-Juniperus spp. 140] Rocky Mountain lodgepole pine* Pinus contorta var. latifolia 25-340 [10,11,172] Sierra lodgepole pine* Pinus contorta var. murrayana 35-200 western white pine* Pinus monticola 50-200 Pacific ponderosa pine* Pinus ponderosa var. ponderosa 1-47 [3] interior ponderosa pine* Pinus ponderosa var. scopulorum 2-30 [3,8,112] red pine (Great Lakes region) Pinus resinosa 10-200 (10**) [53,65] red-white-jack pine* Pinus resinosa-P. strobus-P. banksiana 10-300 [53,87] eastern white pine Pinus strobus 35-200 eastern white pine-eastern hemlock Pinus strobus-Tsuga canadensis 35-200 eastern white pine-northern red oak-red maple Pinus strobus-Quercus rubra-Acer rubrum 35-200 Virginia pine Pinus virginiana 10 to < 35 Virginia pine-oak Pinus virginiana-Quercus spp. 10 to < 35 sycamore-sweetgum-American elm Platanus occidentalis-Liquidambar styraciflua-Ulmus americana 188] eastern cottonwood Populus deltoides 140] aspen-birch Populus tremuloides-Betula papyrifera 35-200 [53,188] quaking aspen (west of the Great Plains) Populus tremuloides 7-120 [3,73,125] black cherry-sugar maple Prunus serotina-Acer saccharum > 1,000 [188] mountain grasslands Pseudoroegneria spicata 3-40 (10**) [2,3] Rocky Mountain Douglas-fir* Pseudotsuga menziesii var. glauca 25-100 [3,5,6] coastal Douglas-fir* Pseudotsuga menziesii var. menziesii 40-240 [3,132,151] California mixed evergreen Pseudotsuga menziesii var. menziesii-Lithocarpus densiflorus-Arbutus menziesii < 35 California oakwoods Quercus spp. 3] oak-hickory Quercus-Carya spp. < 35 northeastern oak-pine Quercus-Pinus spp. 10 to 188] coast live oak Quercus agrifolia 2-75 [70] white oak-black oak-northern red oak Quercus alba-Q. velutina-Q. rubra 188] canyon live oak Quercus chrysolepis <35 to 200 blue oak-foothills pine Quercus douglasii-P. sabiniana 3] northern pin oak Quercus ellipsoidalis 188] Oregon white oak Quercus garryana 3] California black oak Quercus kelloggii 5-30 [140] oak savanna Quercus macrocarpa/Andropogon gerardii-Schizachyrium scoparium 2-14 [140,188] northern red oak Quercus rubra 10 to < 35 post oak-blackjack oak Quercus stellata-Q. marilandica < 10 black oak Quercus velutina < 35 live oak Quercus virginiana 10 to188] interior live oak Quercus wislizenii 3] little bluestem-grama prairie Schizachyrium scoparium-Bouteloua spp. 140] western redcedar-western hemlock Thuja plicata-Tsuga heterophylla > 200 western hemlock-Sitka spruce Tsuga heterophylla-Picea sitchensis > 200 mountain hemlock* Tsuga mertensiana 35 to > 200 [3] elm-ash-cottonwood Ulmus-Fraxinus-Populus spp. 53,188] *fire return interval varies widely; trends in variation are noted in the species reviewFire as a control agent: While experimental evidence is inconclusive regarding St Johnswort's response to fire, much of the available literature suggests that fire increases frequency and density of St Johnswort [20,34,41,154,178]. Therefore, burning is not indicated as a potentially effective method for controlling St Johnswort. Other evidence suggests that, in some cases, burning may provide effective control for St Johnswort. Very little literature examines the effects of prescribed burning intended to control St Johnswort.
According to Sampson and Parker [154], some stockmen contend that burning infestations of St Johnswort when the tops are dry in autumn will kill the present cover and destroy the accumulated seed. By burning 2 or 3 years in succession it was suggested that grass may invade the area and crowd out any remaining St Johnswort plants. To test these suggestions, 300 acres (120 ha) near Blocksburg, California was burned "closely" in October of 1926 and 1927. The fire completely consumed St Johnswort tops, and "carried" to all isolated patches, leaving no tops unburned. Density of St Johnswort was measured before the 1st burn and after the 2nd burn in "representative" areas. However, these data are not reported, nor do the authors indicate how long after burning density measurements were taken. The authors summarize results by stating "instead of the weed cover being killed or subsequently thinned out by invading grasses, the stand of St Johnswort was denser and seemingly more vigorous than before." They further suggest that not only does fire stimulate germination of St Johnswort seed, but that repeated burning may deplete the soil of organic material and thus favor St Johnswort and other undesirable plants [154]. Similarly, at Dye Creek and Vina Plains Preserves in California, St Johnswort is said to be encouraged by burning, and the preserves' manager recommends against using prescribed fire in St Johnswort-infested areas [149].
Conversely, preserve managers for The Nature Conservancy in Michigan and Ohio indicate that fire suppression encourages invasion of St Johnswort, while burning and restoration treatments discourage invasion of St Johnswort. At Kitty Todd, Ohio, where St Johnswort is found in areas that were previously farmed and grazed and around old homesites, burning "seems to be somewhat effective" as a control method for St Johnswort. Unfortunately, further details on how and when burning was conducted are not available [149].
According to Jack McGowan-Stinski, Fire Manager for Michigan sites of The Nature Conservancy, St Johnswort has been reduced or eradicated with both prescribed fire and spot-burning (using propane torches), with and without additional control methods. Control, using either prescribed or spot-burning, is most successful in dry sand prairies and oak barrens, possibly due to nutrient-poor soil conditions. Prescribed burning on sites where there is a diversity of native prairie grasses (little bluestem, big bluestem, prairie dropseed (Sporobolus heterolepis), and sideoats grama (Bouteloua curtipendula)) and native forbs eliminates St Johnswort when burning is conducted during the growing season or early fall (June, July, August), and repeated for 2 to 3 consecutive years. Native plants on these sites are adapted to fires during this season and out-compete St Johnswort in the postfire environment. In areas with dense St Johnswort populations, repeated spot-burning has successfully reduced or eliminated St Johnswort. This is also likely due to native perennial prairie plants' tolerance of repeated burning (in the same year) in late summer or early fall. Prescribed or spot burning followed by hand removal of St Johnswort sprouts and seedlings by volunteers throughout the season is also successful. The advantages of burning followed by hand removal include fewer restrictions by weather, staff time, and equipment, and lower associated costs [123].
Fire interactions with other control methods: Fire managers may need to include the existence of biological control agents in their decision making process and fire management plans. Fire may adversely affect populations of biological control agents and thus lead to increases in host plant populations. In the Awatere Valley of New Zealand, the only reported resurgence of St Johnswort following successful control by Chrysolina hyperici occurred following a fire (Syrett 1989, as cited by [20]). Intensity, frequency, and season, plus scale of individual fires are important for both the host weed and the biological control agent. The final outcome depends on how a particular weed or biological control agent responds to these components of the fire regime [20].
One study in Australia examines effects of fuel reduction burns on biological control of St Johnswort. Details of the study site and St Johnswort response to burning are given above (see Discussion and Qualification of Plant Response). St Johnswort on this site supported populations of C. quadrigemina, a chrysomelid beetle introduced to Australia for biological control of St Johnswort [20].
The immediate effect of the spring 1982 prescribed fire on C. quadrigemina was the virtual disappearance of the insect during 1983, with only a few eggs observed during that period. In autumn 1984, massive egg-laying and subsequent larval defoliation of rosettes were observed, most likely due to re-invasion by adult beetles from neighboring unburned plots. Large-scale destruction of St Johnswort by beetles was repeated in 1985. This resulted in a substantial decrease in St Johnswort ground cover, crown density, and production of flowering stems, and an increase in dominance of the grass and forb component in both open and timbered areas. Briese [20] suggests that a short term postfire increase in soil nutrients ("the fertilizer effect") may have contributed indirectly to the impact of the biological control agent on St Johnswort. Nutrient analyses of St Johnswort plants collected the season following the fire showed a 25% increase (p<0.05) in nitrogen levels in plants from burned areas relative to plant from adjacent unburned areas. Burned plants were also larger than average, which may have been particularly attractive to beetles and/or favor survival and development of hatching larvae, thus triggering a population build-up of the biological control agents [20].
Following the fall 1986 fire, St Johnswort populations and associated grasses and forbs responded much differently, with massive seed germination of several species, including St Johnswort. Most St Johnswort seedlings did not survive and persist, and associated grasses and forbs dominated the postfire environment. Large populations of C. quadrigemina were not observed on the site until 1990 [20].
Frequency of fire is a key factor for effects on biocontrol agents, and the cycle of their population build-up needs to be understood and respected to enable them to have the desired impact on the target weed. The frequency of prescribed burning may need adjusting according to the reproductive capacity and life history of the control agent. Reproductive strategy and mobility of control agents are important factors to consider. If one considers both fire management and biological control as long-term protection strategies, it is necessary to look at the interaction of weed biology, control agent biology, fire regime, and whether they can be manipulated to help realize the potential of the control agent, or at least to not hinder it [20].
Postfire colonization/spread potential: Several sources suggest that St Johnswort has high potential for postfire colonization in some areas. Several references indicate that St Johnswort often occurs in previously burned areas, especially forests (e.g. [34,39,41,113,128,169,178]). The source (seeds vs. sprouts) of St Johnswort establishment in these references is unclear. St Johnswort may occur in the initial postfire community by establishing from root crowns, roots, or seeds in the soil seed bank, or it may occur in burned areas as a secondary colonizer, establishing from off-site sources some years after fire.
Where St Johnswort occurs as mature plants, it is likely to occur in the initial postfire community (e.g. [20,40,115,180]), although it may or may not persist (See Successional Status). Several studies in which the soil seed bank was sampled and germinated indicate the presence of St Johnswort seed in areas where mature plants are rare, do not occur, or occur only at some distance from the sampled sites [76,111,114,117,197]. Harris and Gill [81] suggest that when a pine plantation (or forest) reaches stand closure, St Johnswort may disappear from aboveground vegetation, but remain (as seed) in the soil seed bank (see Seed banking for details). When fire occurs in such sites, St Johnswort may establish from seed as part of the initial postfire community. Rapid postfire infestation of St Johnswort following prescribed burning on an Oregon range site suggests that an extensive seed bank was present on the site before the fire [189] (see Discussion and Qualification of Fire Effect). Evidence of St Johnswort establishment following disturbances from timber harvest or thinning (e.g. [51,176]) further support the possibility of St Johnswort establishment after a fire that reduces or removes canopy cover and/or disturbs the soil.
Although there is no clear evidence in the literature, managers should be aware that St Johnswort may also establish as an initial off-site colonizer in areas where St Johnswort populations are in the vicinity of a burn site and seed may be transported by wild or domestic animals, or by vehicles.
St Johnswort may also establish as a secondary off-site colonizer that establishes after postfire year 1 [164]. Evidence to support this is provided from several forested habitats in Idaho [75,164,166], where St Johnswort established several years after fire and did not persist as canopies established. St Johnswort may, however, persist in closed-canopy Douglas-fir forests (e.g. [153]), as well as in more open-canopied forests such as some eucalyptus [22,24] and ponderosa pine forests [178] (see Successional Status).
Several authors suggest that spread of St Johnswort is also encouraged by fire in some areas and under some conditions [20,149,154,189].
According to Campbell and Delfosse (1984) when stands of St Johnswort are burned, density of the stand increases. Thus, control of rangeland fires may be important to the control of St Johnswort [45].
Preventing postfire establishment and spread: The USDA Forest Service's "Guide to Noxious Weed Prevention Practices" [181] provides several fire management considerations for weed prevention in general that apply to St Johnswort.
Preventing invasive plants from establishing in weed-free burned areas is the most effective and least costly control method. This can be accomplished through careful monitoring, early detection and eradication, and limiting invasive plant seed dispersal into burned areas by [68,181]:
In general, early detection is critical for preventing establishment of large populations of invasive plants. Monitoring in spring, summer, and fall is imperative. Managers should eradicate established St Johnswort plants and small patches adjacent to burned areas to prevent or limit dispersal into the site [68,181].
The need for revegetation after fire can be based on the degree of desirable vegetation displaced by invasive plants prior to burning and on postfire survival of desirable vegetation. Revegetation necessity can also be related to invasive plant survival as viable seeds, root crowns, or root fragments capable of reproduction. In general, postfire revegetation should be considered when desirable vegetation cover is less than about 30% [68].
When prefire cover of St Johnswort is absent to low, and prefire cover of desirable vegetation is high, revegetation is probably not necessary after low- and medium-severity burns. After a high-severity burn on a site in this condition, revegetation may be necessary (depending on postfire survival of desirable species), and intensive monitoring for invasive plant establishment is necessary to detect and eradicate newly established invasives before they spread [68].
When prefire cover of St Johnswort is moderate (20%-79%) to high (80%-100%), revegetation may be necessary after fire of any severity if cover of desired vegetation is less than about 30%. Intensive weed management is also recommended, especially after fires of moderate to high severity [68].
Fall dormant broadcast seeding into ash will cover and retain seeds. If there is insufficient ash, seedbed preparation may be necessary. A seed mix should contain quick-establishing grasses and forbs (exclude forbs if broadleaf herbicides are anticipated) that can effectively occupy available niches. Managers can enhance the success of revegetation (natural or artificial) by excluding livestock until vegetation is well established (at least 2 growing seasons) [68]. See Integrated Noxious Weed Management after Wildfires for more information.
When planning a prescribed burn, managers should preinventory the project area and evaluate cover and phenology of any St Johnswort and other invasive plants present on or adjacent to the site, and avoid ignition and burning in areas at high risk for St Johnswort establishment or spread due to fire effects. Managers should also avoid creating soil conditions that promote weed germination and establishment. Weed status and risks must be discussed in burn rehabilitation plans. Also, wildfire managers might consider including weed prevention education and providing weed identification aids during fire training; avoiding known weed infestations when locating fire lines; monitoring camps, staging areas, helibases, etc., to be sure they are kept weed free; taking care that equipment is weed free; incorporating weed prevention into fire rehabilitation plans; and acquiring restoration funding. Additional guidelines and specific recommendations and requirements are available [181].General: In California, the Pacific Northwest, and the Intermountain area, where St Johnswort is most problematic, it occurs most commonly and develops best in pastures, open grasslands, abandoned fields, and disturbed places [89,136,154,178]. It occupies all slopes and aspects [154]. Observations by Walker [189] suggest that, while St Johnswort is common along roadsides in forested areas California and Oregon, populations tend to extend further from roadsides into adjacent plant communities in California than in Oregon. In forest zones in Idaho, St Johnswort is abundant only in small, localized areas in naturally open ponderosa pine forest stands or in areas where tree cover has been greatly reduced by logging, fire, or other disturbance (e.g. in Douglas-fir, western redcedar-western hemlock, and fir-spruce zones). Serious spread of St Johnswort into "well-stocked" forest stands in Idaho has been observed only in ponderosa pine [178]. Similar site characteristics are described for areas where St Johnswort is invasive in Australia [34,41], although a large proportion of infestations (estimates of 80%) occur under native eucalyptus forests (Shepherd 1983, as cited by [22]).
In Colorado, St Johnswort is locally abundant on piedmont valleys and outer foothills, but mostly kept in check by biological control insects [192,193]. In central North America, St Johnswort is found primarily in the central and eastern Great Plains and scattered westward in fields and along roadsides and ditches, as well as moist ravines (or low, moist ground), prairies, pastures, open woods, and rangeland. It is not considered as serious a problem as it is in northwestern North America [9,69,163,170]. At Matfield Green, Kansas, distribution of nonnative plants, including St Johnswort, formed a gradient from high abundance in the townsite and along truck trails, to low abundance in the surrounding prairie [56]. In Michigan, St Johnswort is abundant on fields and along roadsides and railroads, and may spread to rock outcrops, dunes, and shores [149,187]. Along the Atlantic coast from Newfoundland to northern Virginia, St Johnswort may occur in meadows, fields, between stable dunes, along marsh edges, on beaches, and along roadsides [54]. In other parts of North America, St Johnswort seems to be less invasive and is most commonly found along travel corridors (roadsides and railways) [67,77,108,127,145,199], in fields and pastures [16,67,77,100,108,127,145,152,168,199], and in "waste places" [16,77,100,108,168].
Elevation: While temperature, precipitation, and elevation are important in influencing the spread of St Johnswort in local areas [154], relatively little information is available regarding elevational limits for St Johnswort throughout its introduced range. Some elevations of occurrence by geographic area are given as follows:
Geographic area Elevation Reference CA below 5,000 feet (1,500 m) [89,136] CO 5,500 feet (1,680 m) [77] ID 743 to 4,000 feet (226-1,220 m) [177,178] MT 3,000 to 5,000 feet (900-1,500 m) [189] NV 4,000 to 5,000 feet (1,200-1,500 m) [100] OR up to 3,330 feet (1,000 m) [160,189] Adirondack area 2,880 feet (880 m) [108] Australia below 5,000 feet (1,500 m) [41]St Johnswort requires a moderately warm and long growing season for completion of its life cycle [41,154]. In California, the densest and most extensive stands described in the 1930s were usually found only a few hundred feet above sea level, with 1 vigorous stand known to occur at sea level (in Humboldt County). At elevations of 4,000 feet and higher, St Johnswort stands are open and plants less vigorous than at lower altitude [154]. Tisdale [177] reports that early infestations of St Johnswort in Idaho occurred between 1,200 and 4,000 feet, (370-1,220 m) but rarely occurred above 3,500 feet (1,100 m). In Australia, the most vigorous infestations of St Johnswort occur at altitudes of about 2,000 feet (600 m) [34], and the highest altitude at which St Johnswort occurs is between 4,500 and 5,000 feet (1,400-1,500 m), where a small patch was found [41]. Clark [41] and Sampson and Parker [154] speculate that St Johnswort's absence at higher elevations is due to low temperatures and short growing seasons that would limit St Johnswort seed production and seedling survival.
Temperature: Where St Johnswort thrives in Idaho, mean monthly temperatures range from 67 to 77 °F (19-25 °C) in July and 27 to 34 °F (-3-1 °C) in January [178]. In Canada, St Johnswort occurs in the mild mesic, moderately cool boreal and cool boreal soil temperature classes (Canada Dept of Energy, Mines, and Resources 1970, as cited in [45]). St Johnswort is restricted by low temperatures at high elevations (above about 5,000 feet (1,500 m)) [41,154] and is restricted by a normal mean January temperature over 75 °F (24 °C) at lower elevations (Campbell 1977 as cited by [34]). In South Australia and Western Australia, where the growing season is short, St Johnswort grows in scattered open communities. This contrasts with the dense stands in New South Wales and Victoria (Moore and Cashmore 1942, as cited by [34]). In the northernmost part of St Johnswort's North American distribution the length of the growing season is approximately 160 days, and in the most southern portion it is 210 to 220 days [45]. In experiments performed near the northern boundary of St Johnswort's European distribution in England, Fox and others [62] found that experimental winter warming increased spring growth in St Johnswort, but had mainly negative effects on St Johnswort populations. Winter warming increased herbivory with normal rainfall or drought, but not with increased precipitation. Summer drought reduced St Johnswort's reproductive success indirectly by increasing its vulnerability to herbivorous insects [62].
Moisture: Precise moisture requirements for St Johnswort are unclear. In Australia, St Johnswort is said to grow in areas with mean annual rainfall greater than 30 inches (760 mm) [24]. Harris [78] indicates that North American St Johnswort populations require 35 to 40 inches (890-1,020 mm) of annual precipitation in areas where winter precipitation occurs in the form of rain, as in much of California; while in regions with heavy winter snows, St Johnswort may require little as 10 to 12 inches (250-300 mm) of annual precipitation. In areas receiving less than 10 inches (250 mm) annual precipitation St Johnswort invades drainageways where soil moisture is more abundant [78,154]. In northern Idaho, St Johnswort thrives in areas where mean annual precipitation ranges from 12 to 24 inches (300-610 mm) and soil moisture content is consistently reduced to 10 to 14% in the top 12 to 18 inches (30-46 cm) by early July. In several cases observed by Tisdale and others [177,178], St Johnswort plants remained green and apparently well supplied with moisture for periods of 2 to 4 weeks, when no available moisture was present above the 24-inch (61 cm) soil depth. Similarly, in California, soil in the upper 6 inches (15 cm) in St Johnswort-infested areas was near the wilting point from mid-spring throughout the summer. When the earliest St Johnswort flowers appear, late in April, the moisture in the upper soil layer has been exhausted and moisture is then drawn by St Johnswort almost entirely from depths of 10 to 35 inches (25-89 cm) [154].
Kudish [108] suggests that native Hypericum species in the Adirondack area require high water tables, but St Johnswort grows in well-drained sites and does not do well on poorly drained sites. This appears to be true in much of its introduced range [78,154]. Similarly, in an area on the Willamette Floodplain Research Natural Area in western Oregon, where mean annual precipitation is 40 inches (1,004 mm), St Johnswort cover has a moderately strong negative correlation (r=-0.91) with soil moisture index, which is related to microtopography. This area is characterized by a microtopography of mounds about 20 inches (50 cm) higher than the surrounding intermound matrix, and St Johnswort has higher cover on mounds (25.3%) than intermounds (0.9%), where soil moisture index is highest [169].
A review by Campbell and Delfosse [34] suggests that in Australia, St Johnswort is restricted by average annual rainfall of <20 inches (500 mm) at lower altitudes, and that the most vigorous infestations of St Johnswort occur in areas with an annual rainfall of >30 inches (760 mm). Drought may severely affect the appearance of a St Johnswort infestation, through reduced cover and flowering stem production, but will not reduce crown densities unless it is prolonged [22]. Regional differences in precipitation requirements may be due to different ecotypes of St Johnswort and/or to differences in soil types.
Soils: St Johnswort grows in a wide variety of soil types, and soil parameters that may affect St Johnswort establishment and growth include moisture status, texture, fertility, depth, and pH. St Johnswort seems to prefer well-drained, coarse-textured soils [69,152,154,170]. In Washington, dense stands have become established on eroded, infertile areas of gravelly silt loam and on coarse sandy loam soils, as well as on fertile valley-bottom pasture land [78]. Soil fertility and depth may affect the growth habit and longevity of St Johnswort plants as observed in Australia (see Growth habit/stand type).
Soil pH may affect St Johnswort germination, establishment, and persistence, although experimental results are varied. Observations by Daubenmire (1947, as cited by [45]) and Sampson and Parker [154] suggest that St Johnswort is not common on calcareous soils, and seems to prefer soil with slightly acid to neutral pH. In California, Sampson and Parker [154] observed that while St Johnswort is not restricted to soils of either acid or alkaline reaction, unusually luxuriant growth and dense stands are more typically found on soils with pH 5 to 6.5, while very vigorous growth was not observed on strongly alkaline soils [154]. St Johnswort plants sprouted from lateral roots developed much more vigorously and flowered more profusely in acid medium (pH 6) than in alkaline medium (pH not given). Plants in alkaline medium did not form flowers, were smaller, and had light green foliage. Plants grown in extremely acid cultures (pH 3 to 4) died [154]. Borthwick [17] suggests that St Johnswort seed germination is inhibited by calcium ions. However, Campbell [32] found that neither added calcium nor calcium resident in the soil had a significant effect (p<0.05) on St Johnswort germination. Similarly, St Johnswort occurs on alkaline soils with pH ranging from 7.1 to 7.7 in an oak (Quercus spp.) savannah community type in on Pelee Island in the western Lake Erie archipelago [103]. St Johnswort also occurred only on plots (100% of them) that were previously plowed and had soils with high calcium and magnesium concentrations and higher pH (limed in past) than surrounding vegetation types in a Massachusetts study [133]. Additionally, of 5 woodland sites studied in southwestern England, St Johnswort seed was found only in the seed banks of the sites with basic soils, and not in acid soils (pH not given) [191]. Clark [41] suggests that St Johnswort infestation may be more strongly related to land use than to soil type.
Disturbance: As indicated in the discussion of general site characteristics, St Johnswort commonly occurs on disturbed sites such as agricultural fields, roadsides, railways, and "waste places," as well as forests disturbed by roads, logging, fire, and other factors that open the forest canopy. In California, St Johnswort invaded areas on denuded slopes and semi-exposed soils, where much of the surface soil horizon had been removed [154]. Much of the open forest and grassland areas in the Pacific Northwest and Intermountain area where St Johnswort infestations are most severe have (1) a history of heavy grazing [49,78,154,200], and (2) plant communities that are altered from their native condition and often dominated by nonnative species (see Successional Status). Where St Johnswort occurs in forested habitats, it seems to occur primarily on sites with some history of disturbance.
Impacts: Earlier literature (e.g. [41,154,178]) seems to indicate greater impact from St Johnswort than is currently indicated in many areas. This is perhaps due to suppression of many St Johnswort populations by introduced biological control insects (see Biological control), or to its ubiquity. In California, for example, where St Johnswort populations have been historically widespread, St Johnswort is listed as a "wildland plant of lesser invasiveness" by the California Invasive Plant Council (Cal-IPC), and as a weed that is "so widespread that the agency does not endorse state or county-funded eradication or containment efforts" by the California Department of Food and Agriculture [30]. St Johnswort occurs in 44 states and 7 Canadian provinces but is designated as noxious in only 7 states and 2 provinces [183].
In agricultural areas, St Johnswort is more of a problem in pastures than in cropland because it is controlled by regular cultivation [139]. The most commonly described impacts of St Johnswort are loss of forage production and carrying capacity on rangelands and pastures, and losses from livestock poisoning [45,143,154,178].
Hypericin, a chemical constituent of St Johnswort found at all growth stages in either fresh or dry foliage, causes photosensitization in animals that consume it. Symptoms such as blistered skin and edemas have been reported in cattle, horses, domestic sheep, and domestic goats, with goats being most resistant, and light-colored animals of all classes being the most sensitive. Horses are more susceptible to hypericin toxicity than cattle, cattle more than sheep, and sheep more than goats [19]. Livestock rarely die directly from St Johnswort ingestion; however, effects of poisoning such as blindness or swelling and soreness of the mouth may prevent affected animals from foraging and drinking, and thereby contribute to death by dehydration and/or starvation. Several authors provide more detailed descriptions of St Johnswort poisoning and conditions under which it is likely to occur [19,34,102,139,143,154,163]. Some authors (e.g. [102,139]) also suggest that St Johnswort may cause contact dermatitis in humans.
Control: Much of the information on control of St Johnswort presented in this review comes from literature reviews and literature that provided additional pertinent ecological information.
Control of St Johnswort infestations requires several strategies designed to impact different plant parts and different stages in the plants life history. Emphasis on particular strategies may differ according to site type and St Johnswort growth habit. For example on rich soils, large St Johnswort plants with less root development may be easier to control by killing aboveground St Johnswort plant parts and then planting desirable plants, compared to the more difficult-to-control St Johnswort plants with greater root biomass in harsher sites [22,41]. With all St Johnswort control efforts, it is important that control measures are begun early and sustained for a sufficient length of time, as populations of St Johnswort can build from just a few seeds up to dense infestations in a short period of time (about 10-20 years) [25].
St Johnswort shows considerable variation in growth form, extent of vegetative reproduction, response to stress, and flowering frequency (see General Botanical Characteristics). Much of this plasticity can be related to variation in site; therefore, management strategies must be site-specific. Genotypic differences and the effects that these differences may have on susceptibility to different biological control agents have also been noted in St Johnswort ([46], and references therein).
St Johnswort seedlings are highly susceptible to competition, and the presence of competitive plant species is important to reduce the impact of periodic peaks in St Johnswort germination, establishment, and spread. Maintenance of vigorous pasture and rangeland by effective grazing management can prevent such seedling recruitment and limit St Johnswort spread. Effective grazing management plans in Australia are discussed by several authors [28,46]. In areas where vegetation is too sparse to suppress germination and recruitment of St Johnswort seedlings, other control efforts may be emphasized [22]. Any management strategy must also consider the presence of a viable soil seed bank for at least 20 years following control of St Johnswort (see Seed banking).
Based on results using detailed data from a long-term (6-7 years) observational study of St Johnswort populations, and an individual-based modeling approach for St Johnswort, Buckley and others [25] predict that the most effective management strategies for both open and shaded sites would concentrate on reducing the size of vegetative parts of St Johnswort. This may be especially true for infestations on harsh sites that tend to support St Johnswort populations with more lateral roots and root sprouts [22,41]. Single stresses, even if severe, are usually insufficient as St Johnswort root reserves respond with increased rates of sprouting from damaged roots and root crowns [22]. For example, beetles introduced for biological control defoliate St Johnswort plants but are not effective alone, especially in shaded sites (see Biological control) [25]. Multiple stresses such as defoliation and plant competition, defoliation and drought, or defoliation and fire, may cause reductions in St Johnswort crown density, and management of these factors is important for control to be successful [22,46].
Exhausting St Johnswort root reserves may require repeated stresses over a long period of time. Continuous low level herbivory through managed stock grazing may achieve this, although St Johnswort toxicity may limit grazing and a rotation of different types of grazing animals is recommended [19,28]. In its native range in Europe, crashes in population density of St Johnswort are associated with the destruction or exhaustion of root reserves by natural arthropod enemies. This has led to the current biological control strategy of targeting this part of St Johnswort's life history ([22] and references therein).
More research is needed to determine which factors affect the early stages of St Johnswort growth and recruitment, both from seed and sprouts, under different conditions, including fire treatment [25]. Whatever combinations of management techniques are adopted, a clearer understanding of the population dynamics of St Johnswort in different habitats should enable them to be better meshed together and their effects evaluated [22].
Prevention: The most effective method for managing invasive species is to prevent their establishment and spread. Some methods of prevention include limiting seed dispersal, containing local infestations, minimizing soil disturbances, detecting and eradicating weed introductions early, and establishing and encouraging desirable competitive plants [157].
Even though St Johnswort has a widespread distribution in North America, there are many areas where it has not yet established and other areas where it remains at low densities. Preventing further introduction and spread to uninfested areas is much easier, more environmentally desirable, and more cost-effective than is the subsequent management of large-scale infestations. Some aspects of prevention include curtailment of weed development along transportation and utility corridors, inspections and cleaning of machinery and vehicles prior to their movement from weed-infested to uninfested sites, and revegetation of disturbed soils with site-appropriate plant species to inhibit St Johnswort entry. Upon discovery, pioneer St Johnswort plants should be eliminated [143]. A similar approach to St Johnswort management in National Parks in Australia is described by Knutson [105], but also includes a comprehensive biological control program for large infestations, utilizing as many available organisms as possible.
Weed inventory and monitoring are important for early detection of new infestations and prevention of spread [97]. St Johnswort colonies with as low as 30% ground cover are distinguishable from other rangeland vegetation in multispectral digital images with 0.5, 1, 2, and 4 m spatial resolution taken from airplanes. This procedure provides a method to establish baseline plant community composition and a way to monitor species population changes and dispersal over time. See Lass and others [110] for details.
Because St Johnswort infestations may be serious on overgrazed areas, adoption of grazing systems that increase or maintain cover of desirable plants and/or reduce the amount of St Johnswort seed produced is a worthwhile preventative tactic [139,154]. St Johnswort occurs along roadsides and fencerows but rarely invades "properly managed" pastures (Lane 1979, as cited by [45]).
Integrated management: Controlling St Johnswort infestations requires more than defoliation or removal of aboveground plant parts. St Johnswort's ability to spread vegetatively and its apparent stimulation by defoliation (e.g. [41,178]) necessitate an intensive, integrated approach to control. An effective suppression program for St Johnswort requires planning, use of appropriate management methods, monitoring/evaluation, and persistence [143]. Integrated management includes considerations of not only killing the target weed, but also of establishing desirable species and maintaining weed-free systems over the long-term.
It is important to determine whether St Johnswort is a new or established invader in a particular infestation, because management approaches to each type will differ. With new infestations, emphasis may be placed upon early treatment and prevention, followed by monitoring and removal of newly established plants. Revegetation may also be useful to deter further St Johnswort invasion of the site. When dealing with an established population, the management approach may be more involved and take longer to implement. An established St Johnswort population is comprised of outlier, perimeter, and core plants. Management activities are prioritized based on plant location within the infestation. The 1st priority is management of the outlier populations to restrict continued spread of the infestation, followed by plant suppression within the perimeter and core infestation zones, respectively. Physical extraction and herbicides can be used against outlier plants [143]. A mixture of physical, cultural, chemical, and biological methods, chosen to cause multiple stresses to target plants, may be used to contain and eventually reduce perimeter and core population plants [22,143].
It is not possible or realistic to detail procedures to be followed in every potential management situation. The decision to use a combination of management methods must be based upon an assessment of plant developmental status, a characterization of sites infested or susceptible to infestation, and constraints of particular methods. Emphasis should be placed on the use of methods that interrupt St Johnswort seed dispersal and longevity, and that minimize habitat perturbations [143]. Site-specific integrated management programs can be developed for St Johnswort or other weeds ([143], and references therein).
Physical/mechanical: Several physical methods have been used for St Johnswort management including hand-pulling or digging, cutting or mowing, tillage, mulching, and flooding. Effectiveness of various physical methods depend on age, size, and location of St Johnswort infestations. For example, St Johnswort can be effectively managed by repeated tillage in intensively cropped situations [45]; however, tillage is rarely appropriate for natural areas.
Hand-pulling or digging of young, isolated plants is often effective, but is not considered practical for large populations of established, deeply rooted plants. Sampson and Parker [154] suggest "the mere digging, grubbing, and hand pulling of St Johnswort have proven costly and ineffective as a control measure." They observed sprouting from St Johnswort roots wherever segments were left in the surface soil, and numerous St Johnswort seedlings where adult St Johnswort plants had been dug [154]. Conversely, on prairie and dune sites on conservation preserves in Michigan, persistent annual pulling of mature St Johnswort plants to prevent seed production has been an effective control method. At Kitty Todd, Ohio, pulling is very effective, especially for early eradication of new St Johnswort populations [149]. It is important to remove as much of the root as possible, while minimizing soil disturbance, and removing all St Johnswort plant parts from the area to prevent possible vegetative growth or seed dispersal [143].
Cutting and mowing are typically considered ineffective as management methods for St Johnswort since sprouting may occur immediately after crown removal or defoliation [34,45,149,154]. These methods may be useful for preventing seed formation in St Johnswort [143,154], by cutting 2 or more times during the growing season [143].
Repeated mowing or cutting may weaken and eventually "starve" St Johnswort plants, and thus reduce population density [41,154]. St Johnswort is particularly susceptible to defoliation in spring. In Australia, hand defoliation every 2 weeks from late April to mid-November or from mid-August to early December resulted in from 93%-98% to 87%-100% destruction of crowns in low and high density stands, respectively. Hand defoliation from mid-August to mid-November or from early October to early December killed high density stands, and reduced crown density of low density stands by 72%-92%. Hand defoliation of St Johnswort in a eucalyptus forest in Australia resulted in the death of only 45% of crowns [41]. Survival of St Johnswort plants after hand defoliation depends on the tendency of the plant to reproduce vegetatively and the life span of the individual crown [34,41]. Cutting and/or mowing may not be feasible on many sites because of inaccessible terrain and potential damage to desirable plants [143].
Cultivation/tillage: St Johnswort is usually controlled by tillage and is not usually a problem in cultivated crops. Tillage is more effective when combined with sowing of competitive pasture or crops and adding fertilizer ([34,45] and references therein). In western Washington, St Johnswort density was reduced nearly 70% within 2 years following disking and seeding to cool-season introduced grasses (Gates and Robocker 1960, as cited by [116]).
Mulching/solarization: Sampson and Parker [154] killed St Johnswort by cutting plants to 2 inches (5 cm) above the ground surface and covering them with heavy tar paper. They did not indicate how long it took.
Flooding: There is no literature available regarding flooding as a control method for St Johnswort, although it may be effective since St Johnswort does not thrive in waterlogged soils [154].
Fire: See the Fire Management Considerations section of this summary.
Biological: Biological control of invasive species has a long history, and there are many important considerations before the implementing a biological control program. Tu and others [179] provide information and considerations for biological control of invasive species in general in their Weed Control Methods Handbook. Additionally, Cornell University, Texas A & M University, and NAPIS websites offer information on biological control.
There is a great deal of literature on biological control of St Johnswort in North America and Australia. The following discussion is based on literature reviews (e.g. [45,48,82,116,143]) and primary literature that discusses impacts [177], and/or population dynamics of St Johnswort and biocontrol insects in California [93], northern Idaho [31], British Columbia [84], and Australia [20,21].
Biological control of St Johnswort was initiated in Australia. A total of 12 insect species was released over 70 years, 6 of which established ([21] and references therein). Although early results were promising and led to biological control programs in other countries, including parts of North America, biological control has not yet managed to reduce St Johnswort infestations to levels that do not cause unacceptable economic or environmental damage in many areas. The Chrysomelid beetles (Chrysolina quadregemina and C. hyperici), for example, impact St Johnswort populations in certain situations, but are unable to prevent its continued spread [21].
From 1945 to 1946, shipments of both Chrysolina spp. were obtained from Australia and released in California. Within 2 years, both species were well established. This was the 1st attempt at control of a weed species by the intentional introduction of insects into North America [143]. Similar to initial results in Australia, Chrysolina spp. released in North America had a substantial impact on St Johnswort populations in many areas. In northern Idaho, the overall abundance of St Johnswort fluctuates around 3% of what was present before insects were introduced [177]. On annual grasslands in northern California, St Johnswort was reduced to less than 1% of its former occurrence 10 years after establishment of biocontrol insects [93]. The beetles were so successful in California that a 6-foot bronze statue of C. quadregemina was erected in the town of Eureka [129].
In some areas, however, biocontrol impacts are not as severe, and beetle populations do not reach high densities, probably due to climatic differences [116,139], particularly rainfall patterns [22]. These beetles appear to be adapted to a climate with hot, dry summers and mild, rainy winters [116], but their shade tolerance varies [20,21,24,31]. Other reasons suggested for varying impacts include predation by birds, spiders and other arthropods, and the presence of competing plant species [22].
The following table provides a list of biological control insects introduced to North America and areas where they have established. See the references listed or other reviews for more information.
Biological control agent Locations where established References St Johnswort borer (Agrilus hyperici) CA, ID, MT, OR, WA; mostly in mountain areas; attacks plants growing in shade [31,142] St Johnswort inchworm (Aplocera plagiata) ID, MT, OR, WA, Canada; dry area such as rocky ground, open sandy places, and limestone regions are favored [142] Klamath weed beetle (Chrysolina hyperici) CA, ID, MT, OR, WA; prefers conditions more moist than C. quadrigemina, and avoids shaded or barren, rocky locations [31,84,142] Klamath weed beetleWhile no systematic release of either Chrysolina beetle had been made in the eastern U.S. (as of 1993), C. quadrigemina has been collected from several widespread localities in New York, Pennsylvania, Maryland, West Virginia, and Ohio, since 1989. Its establishment and range expansion in the eastern U.S. apparently resulted from a natural dispersal of populations from eastern Ontario. Several other states in the East where St Johnswort occurs have not been surveyed for Chrysolinids [91].
It may be helpful to fire managers to be aware of which biological control insects may be established in their area, as this affects postfire succession and population dynamics (e.g. [20]). See Fire Management Considerations for more information.
Livestock grazing: Several authors suggest using domestic goats to graze St Johnswort-infested areas to keep St Johnswort at low densities [139,154]. Some authors also suggest that domestic sheep can be used to graze St Johnswort in a rotational grazing system [34,46,116]. In 1 example, a heavy stocking of sheep controlled St Johnswort after a fire. Sheep, however, are more sensitive to St Johnswort toxins, and heavy infestations require 2 week rotations (2 weeks on and 5 weeks off), black sheep, and special management [34]. Cattle may be more effective than sheep under some conditions as they are less sensitive to toxins [19,34,46]. Managing St Johnswort with grazing requires intensive management, as defoliated St Johnswort plants may be stimulated to sprout from roots and root crowns [178]. Also, heavy grazing may do more damage to desirable plants in some situations, thus encouraging spread of St Johnswort.
Chemical: Herbicides are effective in gaining initial control of a new invasion (of small size) or a severe infestation, but are rarely a complete or long-term solution to invasive species management [29]. Herbicides are more effective on large infestations when incorporated into long-term management plans that include replacement of weeds with desirable species, careful land use management, and prevention of new infestations. Control with herbicides is temporary, as it does not change conditions that allow infestations to occur. See the Weed Control Methods Handbook [179] for considerations on the use of herbicides in natural areas and detailed information on specific chemicals and adjuvants.
Based on an individual-based modeling approach for St Johnswort, Buckley and others [24] predict that herbicide control that causes a sustained reduction in survival of at least 90% would be an effective control strategy in both open and shaded sites. They, among others [34,46,143], suggest that other considerations must be taken into account when using herbicides in a control program for St Johnswort. Herbicides are often too costly to be of practical value as a management tool for extensive infestations of St Johnswort. Repeated applications are often required to achieve adequate management, small patches may be missed, the St Johnswort seed bank must be considered for up to 20 years, and potential damage to associated vegetation must also be considered, especially in natural areas. Herbicides are best used as part of a larger, integrated system, and with adequate follow-up (for example planting desirable species, and grazing management) [46,139,143]. Some authors suggest grazing prior to herbicide application to remove nontarget plant biomass that may intercept the spray [139]. Timing and rate of application are important. See specific references, product labels or extension agents for this type of information.
Several herbicides have been used in an attempt to control St Johnswort. Many reviews discuss early attempts at killing St Johnswort with chemicals, many of which are no longer in use. Herbicides found to be effective at suppressing St Johnswort include 2,4-D, glyphosate, picloram, triclopyr, metsulfuron, and fluoroxypyr [36,195].
Campbell and Nicol [36] tested several herbicides for controlling St Johnswort on a site in Orange, Australia. They compared rate and type of herbicide, timing of application, application at annual intervals, rate of water carrier, and spraying combined with sowing of improved pasture species. Herbicides tested were triclopyr + picloram, fluoroxypyr, glyphosate, glyphosate + metsulfuron, and 2,4-D amine + metsulfuron. Results indicate that the only treatment that completely killed St Johnswort was 2 applications at annual intervals in summer of fluoroxypyr. Other herbicides that "substantially" reduced St Johnswort ground cover were triclopyr + picloram, glyphosate, and glyphosate + metsulfuron. Fluoroxypyr had no effect on regeneration of annual legumes and did not damage grasses, whereas triclopyr + picloram killed legumes and other forbs, and glyphosate killed grasses. Spraying St Johnswort and sowing improved species appeared to be the best treatment for long-term control because desirable pasture species established and replaced St Johnswort. Authors conclude that St Johnswort is difficult to control with herbicides and that every effort should be made to promote successful biological control and/or effective grazing management procedures [36]. See [36] for more details.
On prairie and dune sites at nature preserves in Michigan, sponge wick application of glyphosate on cut tops of St Johnswort plants is 100% effective at controlling St Johnswort [149].
Cultural: St Johnswort "competes strongly with other plants" but is itself sensitive to competition in the young stages or after it has been suppressed by cultivation, chemical control, or insects. If St Johnswort is suppressed by 1 or more methods but its ecological niche remains unfilled, reinvasion by St Johnswort or invasion by other undesirable species will likely occur [31,34,143]. Long-term control of St Johnswort requires that competitive plant communities be established and maintained using site-specific range management recommendations [143]. This may be especially difficult in natural areas where native species are desired [46,80].
The choice of plant species to be seeded should reflect site conditions, management, and future use. The Natural Resources Conservation Service, or local Cooperative Extension Service can recommend appropriate plant species for revegetation purposes. Small-scale plantings, evaluated for several years, provide another means to determine which plant species are most competitive with St Johnswort under prevailing climatic and land use conditions [143].
In Australia, a program of seeding pasture species (subterranean clover (Trifolium subterraneum) and canarygrass (Phalaris spp.)) combined with cultivation and fertilization on arable land, and reseeding alone on non-arable land, may control St Johnswort populations in pastures and arable rangeland [34,72]. In New South Wales and Victoria, radical land use change from badly invaded pastures to pine plantations has controlled many areas of St Johnswort because it cannot survive in densely shaded areas. St Johnswort may continue to grow along roads in the forest or plantation and may return when trees are removed [34,72]. It is usually the last species to disappear in a new forest and the first to return when the forest is cleared [34,41,72].
It is important that grazing be carefully managed before, during, and after establishment of desirable species [34,143]. Campbell [33] provides a review of different approaches to grazing management with and without seeding of improved pasture species on St Johnswort populations in heavy and light infestations on Australian pastures.There is no evidence in the literature that St Johnswort provides substantial food or cover for any class of livestock or wildlife. Sampson and Parker [154] indicate that domestic sheep and cattle sometimes eat St Johnswort when other forage is unavailable, and that domestic goats and deer prefer it. St Johnswort is poisonous to most livestock, particularly animals not accustomed to it and light-colored animals (see Impacts for details).
A few birds that nest in California annual grasslands were observed consuming some St Johnswort seed, but in general, birds do not appear to feed extensively upon either foliage or fruiting parts of St Johnswort. Gophers and other burrowing rodents are said to be few on heavy St Johnswort infestations as compared with their numbers on adjoining grasslands [154].
Palatability/nutritional value: Given adequate forage most livestock avoid St Johnswort, although some grazing may occur on St Johnswort in spring when growth is young and succulent, or at other times when more palatable forage is not available [45,154]. Domestic goats and deer seem to prefer it [154].
Cover value: No information is available on this topic.
St Johnswort is treated by many authors as a grassland plant, occurring in pastures,
meadows, and rangelands. It is especially invasive in "low condition range"
[116]. However, St Johnswort is also common in many forested areas in North
America, and may occur in open forests, natural clearings, or within forests
where canopy cover has been reduced or removed by disturbances (e.g. fire, logging, road
construction) (see Site Characteristics and Successional Status). Even in
forested areas where St Johnswort is not found in the aboveground vegetation, it may occur
in the soil seed bank and establish after disturbance (see Seed banking).
In the Pacific Northwest, St Johnswort occurs in a range of habitats and plant
communities, including forest, woodland, rangeland, and prairie communities. In forested
areas, St Johnswort is commonly associated with disturbances such as roads, logging,
grazing, and fire. It is found in various stages of succession in unmanaged, naturally regenerated, closed-canopy forests in the
Douglas-fir/western hemlock (Pseudotsuga menziesii/Tsuga heterophylla) zone of western Oregon and Washington and
northwestern California [153,162] (see Successional Status).
Other major tree species associated
with areas of St Johnswort infestation include grand fir (Abies grandis), western
redcedar (Thuja plicata), bigleaf maple (Acer macrophyllum), and
red alder (Alnus rubra) [189]. Even on sites where
St Johnswort does not
occur in the aboveground vegetation, St Johnswort seeds may be present in the seed bank,
as was observed in a dense, closed-canopy forest dominated by Douglas-fir,
western hemlock, and Sitka spruce (Picea sitchensis) on the Olympic
Peninsula, Washington [76] (see Seed banking for additional examples).
St Johnswort occurs in parts of the Quillayute Prairie along the coastal plain of the
western Olympic Peninsula, Washington, that are dominated by bracken fern (Pteridium aquilinum var.
pubescens). It may occur in similar prairies within the Sitka spruce zone along the coasts
of Washington and Oregon [63]. On the Willamette
Floodplain Research Natural Area in western Oregon, 2 major
plant communities occur. One dominates slightly elevated mounds
and is marked by tall, dense sweetbriar rose (Rosa eglanteria), St
Johnswort, and many other nonnative
species. The other occurs in depressed intermounds and is dominated by shorter
but also dense sweetbriar rose, tufted hairgrass (Deschampsia cespitosa), and many native
species with wetland affinities [169]. St Johnswort occurs
among tufted hairgrass, witchgrass (Panicum capillare) and
nonnative species such as colonial bentgrass (Agrostis capillaris), sweet
vernalgrass (Anthoxanthum
odoratum), and hairy catsear (Hypochaeris radicata) on another
wetland prairie site in Oregon's Willamette Valley [198].
In the interior valleys (between the Cascade and Coast ranges) of western Oregon
and Washington, St Johnswort occurs in grasslands and oak woodlands among species such as
Oregon white oak (Quercus garryana), Oregon ash (Fraxinus latifolia),
sweetbriar rose, Himalayan blackberry (Rubus discolor), poison-oak
(Toxicodendron diversilobum), Douglas hawthorn (Crataegus
douglasii), scotchbroom (Cytisus scoparius), and creeping bentgrass (Agrostis
stolonifera) [40,63,175,180]. In grasslands there
is a high proportion of nonnative species, with many nonnative annual grass dominants,
such as medusahead (Taeniatherum caput-medusae) [63].
In the Interior West region, St Johnswort is common in the ponderosa pine (Pinus
ponderosa) zone in eastern Oregon and Washington, where heavy grazing has
reduced native grasses such as Idaho fescue (Festuca idahoensis), and
dominance has shifted to nonnative species such as cheatgrass (Bromus tectorum),
Dalmatian toadflax (Linaria dalmatica), St Johnswort [49], and rush skeletonweed
(Chondrilla juncea) [137]. Similarly,
where St Johnswort occurs in forest zones in Idaho it is most common in open ponderosa
pine and in logged and burned areas in Douglas-fir, western redcedar-western
hemlock, and fir-spruce (Abies-Picea spp.) zones [39,178]. In the Lochsa River area in north-central Idaho,
St Johnswort occurs on sites that were previously coniferous forest types
(Douglas-fir, grand fir, ponderosa pine, western hemlock, and western redcedar)
until burned in 1919 and 1934. Sites are now dominated by a variety of shrubs
and herbaceous species. For complete species lists see [92,115,134].
In the Blue Mountains of northeastern Oregon and southeastern Washington,
St Johnswort occurs with Kentucky bluegrass (Poa pratensis), Fendler threeawn (Aristida
purpurea var. longiseta), cheatgrass,
Japanese brome (Bromus japonicus), and rattlesnake brome (B. briziformis) on gently sloping benches
formerly dominated by Idaho fescue [94,95]. In
northern Idaho St Johnswort infestations occur on grasslands that were once dominated by
bluebunch wheatgrass (Pseudoroegneria spicata), Idaho fescue, and/or
Sandberg bluegrass (Poa secunda) and are now dominated by nonnative annual grasses, including several brome
species (Bromus spp.) [177]. At Garden Creek Ranch preserve in
Idaho, St Johnswort occurs in large and small populations in bluebunch wheatgrass, Idaho fescue,
and snowberry-rose (Symphoricarpos-Rosa spp.) communities, and in areas where it may
impact populations of Spalding's silene (Silene
spaldingii), a threatened species [149].
In northwestern Montana, St Johnswort occurs among sagebrush (Artemisia
spp.) and Idaho fescue grasslands, and on disturbed forest sites dominated by
Rocky Mountain lodgepole pine (Pinus contorta var. latifolia),
Douglas-fir, western white pine (Pinus monticola), western redcedar,
grand fir, spruce, and/or alder (Alnus spp.) [189].
St Johnswort occurred on
several sites infested with sulphur cinquefoil surveyed by
Rice [150] in western Montana in 1991 and 1992. In 1939,
St Johnswort was listed as occurring along
Bear Creek in Glacier National Park;
the author suggests that it was "possibly of recent introduction to the park"
[120].
In California, St Johnswort is most commonly an invader of California prairies
and annual grasslands [15,85]. It also occurs along
roadsides in many forest types such as those characterized by ponderosa pine,
Pacific madrone (Arbutus menziesii), grand fir, bigleaf maple, and giant
chinquapin (Chrysolepis chrysophylla), and St Johnswort infestations may
extend into the forests in these areas [189].
St Johnswort occurs along edges
(e.g. roads, streams, etc.) at Dye Creek and Vina Plains preserves
in California, in grasslands, riparian areas, blue oak (Quercus douglasii) woodlands,
and vernal pool complexes [149].
In central North America St Johnswort is found primarily in fields and along
roadsides and ditches, as well as moist ravines (or low, moist ground),
prairies, pastures, open woods, and rangelands. It is not considered as serious a
problem here as in the Northwest [9,69,163,170].
St Johnswort is widespread in the Missouri Ozarks and
sometimes common and abundant in
open woods, fields, and "waste areas," as well as streambanks and low ground [44].
In Michigan, St Johnswort is commonly found on abandoned agricultural fields, often
among other nonnative species [57,61]. At Kitty Todd preserve in Ohio,
St Johnswort occurs in mesic sand prairie, Midwest sand
barrens, and black oak/lupine (Quercus velutina/Lupinus spp.) barrens, and may
impact populations of rough false pennyroyal (Hedeoma
hispidum), a threatened species [149].
Literature is sparse for St Johnswort occurring in eastern North America.
However, it seems that St Johnswort occurs in many old field and forest types. It occurs
in several management units at Gettysburg National Park in Pennsylvania. See Yahner
and others [202] for a list of dominant species.
St Johnswort occurs in both burned and unburned
goldenrod-oatgrass (Solidago-Danthonia spp.) fields, and quaking aspen
(Populus tremuloides) groves in south-central New York state [171]. It also occurs with
woodsorrel (Oxalis spp.) and mountain maple (Acer spicatum) in a
beech-maple-birch/aster (Fagus-Acer-Betula/Aster spp.) association in southern New York [196].
On Montague Plain in central Massachusetts, St Johnswort occurred only on plots that
had been previously plowed. Vegetation types
on these sites are characterized by high frequency and cover of forbs and graminoids, especially
little bluestem (Schizachyrium scoparium), and including numerous weedy or early successional species.
Shrubs characteristic of old fields such as white meadowsweet (Spiraea
alba var. latifolia), and common juniper (Juniperus
communis) are also frequent [133]. St Johnswort occurs in various plant
communities on Nantucket, Cape Cod, and Martha's Vineyard. It is most common in
grasslands, especially those dominated by other nonnative species or
by little bluestem. It is less common on shrub-dominated communities [55].
St Johnswort is found in cedar glades in the Big Barren Region of Kentucky
in openings surrounded by eastern redcedar (Juniperus
virginiana) thickets [12]. In the Roanoke River Basin of North Carolina's coastal plain,
St Johnswort is found at the edge of hardwood
forests dominated by many tree species such as white oak (Quercus alba), red
maple (Acer rubrum), American beech (Fagus grandifolia), sweetgum (Liquidambar
styraciflua), and a mix of hickories (Carya spp.). Flowering
dogwood (Cornus florida), blueberries (Vaccinium spp.), and grapes
(Vitis spp.) are common understory dominants [64].
In Canada, St Johnswort occurs in old fields, pastures, abandoned hayfields, and similar
habitats. The frequency of occurrence of St Johnswort and associated species in several
habitats in Nova Scotia is given by Crompton and others [45].
Near Ottawa, Ontario, St Johnswort is occasionally found after fires in alvar
ecosystems (naturally open areas) surrounded by forested areas dominated by
northern white-cedar (Thuja occidentalis), quaking aspen,
balsam fir (Abies balsamea), white spruce (Picea glauca), and
eastern white pine (Pinus strobus) [37,38]. In an old-growth, temperate deciduous forest in
Quebec, St Johnswort was present in the seed bank,
although absent from aboveground vegetation. Overstory dominants there
included sugar maple (Acer saccharum), striped maple (Acer pensylvanicum),
American beech, white ash (Fraxinus americana),
northern red oak (Quercus rubra), eastern hophornbeam (Ostrya virginiana),
basswood (Tilia americana), paper birch (Betula papyrifera),
mountain maple, chokecherry (Prunus virginiana), and yellow birch (B. alleghaniensis) [114].
St Johnswort occurs on Pelee Island, Ontario, in the western
Lake Erie archipelago. Dominant vegetation includes chinkapin oak (Quercus
muehlenbergii), big bluestem (Andropogon gerardii var. gerardii),
blue ash (Fraxinus quadrangulata), eastern redcedar, white oak, hackberry (Celtis
occidentalis), and shagbark hickory (Carya ovata) [103].
St Johnswort has a long history of use for a variety of purposes, including treatment for a variety of ailments from burns and skin disorders to depression. It has been used as an ingredient for distilling vodka, and as a source of red, yellow, purple and orange dyes. In ancient times, St Johnswort was thought to have magical properties and was used as a charm against storms, thunder, evil spirits, and witches. In folklore, it was claimed to bring good luck if sprigs of the plant were hung about the house or carried as a charm and, if you slept with them under the pillow, you would dream of a future lover [9,139]
St Johnswort is well known for its medicinal properties and a great deal of literature is available on this topic, but is beyond the scope of this review. It is cultivated in Europe as a medicinal plant and for use in the cosmetic industry [139,159,189]. Estimated international sales of St Johnswort for 1 year (1997) were between 10 and 12 billion U.S. dollars (Silber and Davitt 1998, as cited by [189]. Everett [58] includes St Johnswort in a guide to nontimber forest products of the Hayfork Adaptive Management Area, Shasta-Trinity and Six Rivers National Forests, California.
St Johnswort seeds germinate in autumn, winter, or spring. Erect woody stems develop in late winter to spring. Flowering and pollen production begin late spring to early summer and continue well into summer, although 1st-year plants do not flower. By mid-summer most petals have withered; seed capsules are moist, green, and sticky; and seeds are green. In early autumn few petals remain, and capsules dry and become less sticky. By late autumn all petals have gone, flowering stems are dry, and capsules contain ripe seeds. Dry flowering stems remain standing for several months, sometimes years [34,45,139,178].
Fall and winter rains initiate procumbent growth in St Johnswort, with prostrate, nonflowering stems up to 12 inches (30 cm) long [34,45,121]. Foliage may be thick on these stems and form a thick mat that smothers other vegetation [34,139]. St Johnswort overwinters in this form, and by seed [45]. Procumbent stems die in late spring [34].
The general phenological pattern observed on a study area in northern Idaho from 1950 through 1956 was as follows [178]:
Drainage Elevation (feet) Start of upright shoots Early bloom Late bloom Early fruit Ripe seed Clearwater 1,200 1st week April 1st week June 2nd week July 4th week July 2nd week September Salmon 1,800 2nd week April 2nd week June 2nd-3rd week July 4th week July 2nd week September Palouse 3,500 4th week April 3rd week June 4th week July 1st week August 2nd-3rd week SeptemberIn northern Idaho, St Johnswort remained green longer than most of the associated vegetation including native perennials. Most seed was ripe by mid-September, and seed dissemination occurred through October and November. At most sites, and in 4 of the 7 years during the observation period, St Johnswort produced fall procumbent basal growth, varying from about 1 to 5 inches (2-13 cm) long. Some winter damage to fall growth was noted, especially on sites with erratic snow cover [178]. Walker [189] provides detailed observations of timing of flowering and seed production at a site in Oregon.
Flowering dates in other parts of North America are given as follows:
Geographic area Flowering dates Reference CA June to September [136] KS June to October [9] southeastern MI June 19 to August 16 [57] NV June to September [100] TX June to September [52] WV June-September [168] Adirondack area July 11 through summer [108] Blue Ridge June to August [199] Carolinas June to September [145] Great Plains June to August [69] north Atlantic coast June to September [54] northeastern U.S. June to September [67] NS July 10-August [152] eastern Canada late June to August [45]It is generally purported that fire encourages establishment, vegetative spread, and increased density of St Johnswort patches [34,41] by stimulating germination of St Johnswort seed (see Discussion and Qualification of Fire Effect) and sprouting in surviving St Johnswort roots and root crowns [20,154,178]. Several references indicate that St Johnswort often occurs in previously burned areas, especially forests (e.g. [34,37,38,39,41,58,113,169,178]).
Accounts in the literature of St Johnswort's response to fire are varied, from no response; to immediate increases in cover and/or density; to immediate decreases in cover and/or density, followed by increases several postfire years later. Because most information available in the literature on St Johnswort's response to fire comes from studies in which the response of St Johnswort to fire was not the primary objective of the study, and because all variables and details of fires are not consistently reported, it is unclear why results differ among reports.
St Johnswort reproduces by seed and by sprouting from lateral roots and root crowns.
Breeding system: St Johnswort is a facultative apomict. Reproduction of St Johnswort throughout Europe is 97% apomictic. St Johnswort pollen undergoes normal meiosis (Robson 1968, as cited by [34]).
Pollination: There is evidence of both self-pollination [9,45,135] and pollination by a variety of insects [9,45] in St Johnswort. Flowers self-pollinated in greenhouse studies developed equally well as those that were cross-pollinated. Field observations in Canada indicated that domestic and wild bees preferred clover (Trifolium spp.) and bird vetch (Vicia cracca) over St Johnswort [45]. In a mid-successional, "prairie-like grassland" in an abandoned field in southeastern Michigan, St Johnswort was "heavily visited" by at least 35 bee species [57].
Seed production: Estimates and measurements of seed production for St Johnswort are variable, but range from about 15,000 to 34,000 seeds per plant on average [45,154,178]. Variation in seed production may result from site factors, seasonal growth conditions, competition, and/or herbivory.
In St Johnswort population studies on 4 contrasting sites in Australia, seed production varied from none to 200,000 seeds per m² over 7 years. The median number of years in which fruit were produced on tagged plants varied from 1 to 3 years, with a maximum of 3 to 7 flowering periods at individual sites over 7 years. A typical pattern was for years of flowering to be interspersed with years in which nonflowering stems were produced (usually drought years), or in which seed production was prevented by insect defoliation. Some crowns never produced fruit, even though they survived for up to 7 years [22].
Salisbury (1942) estimated 26,000 to 34,000 seeds per St Johnswort plant per year in England [178]. Six plants collected in Nova Scotia had 400 to 502 seeds per capsule, with an average of 451. The number of capsules per plant (of 17 plants) ranged from 70 to 76, with an average of 73, giving an estimated total of 33,000 seeds per plant [45]. Sampson and Parker [154] gave a "conservative estimate" of 15,000 seeds on a fully developed St Johnswort plant in California. Tisdale and others [178] examined 512 St Johnswort plants on 6 sites selected to represent the range of conditions within a grassland zone on the Clearwater River in Idaho. They found an average of 69 + 9.8 seeds per capsule, 94 + 12.2 capsules per stalk, and 3.6 + 0.4 flower stalks per plant, estimating an average seed production of 23,350 seeds per plant [178].
Tisdale and others [178] found a high degree of variability in seed production during their field studies in Idaho, with seed production per plant ranging from a few thousand to nearly 100,000. Although not tested, they speculate that this variation could result from site factors, seasonal growth conditions, and/or intraspecific competition. They cite evidence presented by Evanko (1953) in which the number of seeds per St Johnswort plant was much greater in peripheral than in centrally located plants in dense stands of St Johnswort in northeastern Washington [178]. A comparison of annual seed production in St Johnswort in New South Wales, Australia, indicated several differences between 2 years with very different rainfall. Data collected were as follows [34]:
Year 1973 1982 Rainfall (mm) 1,013 235 Seeds per capsule 70 30 Capsules per flowering stem 150 35 Flowering stems per m2 250 100 Seeds per m2 2.6 x 106 1 x 105 Seeds per ha 26.25 x 109 1.50 x 108Seed dispersal: St Johnswort seed can be dispersed by wind, water, humans, and other animals.
Because St Johnswort seeds have no devices to facilitate dispersal by wind, it has generally been assumed that animal or water transport are the main dispersal agents for St Johnswort seed. Tests conducted by Tisdale and others [178] indicate, however, that wind cannot be ignored as a dispersal agent. Seed traps distributed 10, 20, and 30 feet (3, 6, and 9 m) downwind from the nearest St Johnswort plants collected an average of 148, 27, and 7 seeds during the period when most seed at these sites was shed [178]. Walker [189] observed St Johnswort infestations at Kilby Ranch in Oregon over 3 years following a prescribed burn, and suggested that St Johnswort seeds may have been dispersed as far as 0.3 mile (0.5 km) by wind, although this was not tested. This St Johnswort population continues to expand in the direction of prevailing winds [189].
Waterways may also be important dispersal vectors for St Johnswort seed. Comes and others [42] report 7% germination, and 73% of St Johnswort seeds remaining firm after 5 years of storage in fresh water. In another study, germination rates of St Johnswort seed increased with length of time seed was immersed [154]. Similarly, Parsons and Cuthbertson [139] suggest that much of the early spread of St Johnswort in Australia occurred along streams when many infested areas were extensively dredged and sluiced for gold.
Birds and mammals may also aid St Johnswort seed dispersal. The seed is borne in sticky capsules that may adhere to the feet and bodies of birds and mammals ([81] and references therein). It is also suggested that the sticky exudate from the capsule may adhere to the seedcoat and thus aid in seed dispersal [41], or that the seedcoat itself is sticky and/or gelatinous [34,45]. Heavy stands of St Johnswort often occur along livestock driveways and animal trails [34,78,124,139,154]. Some reviews [34,81,139] also suggest that St Johnswort seed remains viable after passing through animals, and may thus be dispersed in the feces of animals that consume it. There is, however, no experimental evidence to support this.
Roads and railroads are also vectors of St Johnswort spread, as seed may be dispersed by humans on vehicles, equipment, and in agricultural products [34,78,139]. Once pioneer plants become established, the stand of St Johnswort may spread to adjoining plant communities.
Seed banking: Some authors suggest that seeds of Hypericum species remain viable in the soil for periods longer than 50 years ([191] and references therein). Evidence from both laboratory and field studies suggests that St Johnswort seed may persist in the soil seed bank for several years, although the ultimate longevity is unclear [41,42,78,81,178]. The combination of a high rate of production and persistence of seed in St Johnswort suggests that any site which has supported a population of St Johnswort for even a few years has a high potential for St Johnswort seedling production for several years after mature plants are removed [81]. Additionally, several studies provide evidence that viable St Johnswort seeds occur in the soil seed bank in areas where mature plants do not occur or occur only at some distance from the sampled sites [76,81,111,114,117,176].
Reports of St Johnswort seed viability following dry storage in the laboratory indicate 94% germination after 5 years [42], and 50% germination after 16 years of storage [178]. Several researchers indicate that St Johnswort seed remains viable under field conditions for several years [41,78,81,178]. Observations by Clark [41] indicated that St Johnswort seeds remain viable in the soil for at least 6 years at field sites in Australia. Bellue (1945, as cited by [78,178]) suggests that St Johnswort seed retains viability in the soil for 10 years in California. Harris and Gill [81] estimate St Johnswort seed longevity at 30 years or more in pine (Pinus spp.) plantations in Australia. Tisdale and others [178] tested viability of St Johnswort seed buried in clay pots at 3 depths over a 3-year period in silt loam soil near Lewiston, Idaho, where mean annual precipitation is about 14 inches (356 mm). Results are as follows [178]:
Number of years buriedGermination (%)
0.5-inch depth 1-inch depth 3-inch depth 1 20.6 27.3 25.2 2 30.6 42 62 3 9.6 45 52These results indicate that a considerable proportion of St Johnswort seed may retain viability for at least 3 years, particularly if buried 1 inch (2.5 cm) or deeper [178].
Several seed bank studies indicate the presence of St Johnswort seed in areas where mature plants are rare, do not occur, or occur only at some distance from the sampled sites. Harris and Gill [81] suggest that when a pine plantation (or a forest) reaches stand closure, St Johnswort may disappear from aboveground vegetation, but remain at the locality in the form of seed in the soil. On a "high-quality" native prairie site in western Oregon, St Johnswort seed was present in the soil seed bank, although St Johnswort plants were not abundant in the prairie [197]. St Johnswort seedlings emerged from a few soil samples taken from 1 site in a dense, closed-canopy forest dominated by Douglas-fir and western hemlock on the Olympic Peninsula, Washington, although St Johnswort was not present in aboveground vegetation [76]. In a grassland remnant surrounded by second-growth woodlands and agricultural fields in a limestone prairie in central Pennsylvania, St Johnswort seed was present in the soil seed bank under grassland and edge vegetation, but not under forest vegetation. St Johnswort was not present in the vegetation aboveground in any of the vegetation types [111]. In an old-growth, temperate deciduous forest in Quebec, St Johnswort was present in the seed bank at 1 of 31 study plots, although it was not present in aboveground vegetation at any of the 31 plots. The authors speculate that St Johnswort seed may have come from surrounding developed areas [114]. St Johnswort seedlings emerged from soil samples from 9 of 13 forest and plantation sites of various ages (from a 5-year-old eastern white pine stand to a 47-year-old eastern white pine plantation) at Harvard Forest, Massachusetts. St Johnswort was not present in aboveground vegetation on these sites, but was present on open field sites nearby, where it was also present in the seed bank [117]. Similar observations were made on sites in Italy [118], England [191], and several other European sites not discussed in this review.
Other studies provide evidence that viable St Johnswort seeds occur in the soil seed bank as indicated by postdisturbance seedling establishment. One year after clearcutting and site preparation (scraping away surface organic layers with a bulldozer) in a 100-year-old eastern white pine stand in northwestern Connecticut, St Johnswort seedlings were frequent (5 to 15 seedlings in about 2,900 m²) to abundant (over 100 seedlings in about 2,100 m²). It is unclear if and where mature St Johnswort plants occurred in the area of the clearcut, or how long the seeds may have been buried [51]. Thysell and Carey [176] examined 1- and 3-year responses of understory plants to variable-density thinning of 55- to 65-year-old stands of Douglas-fir on Fort Lewis Military Reservation, Washington. St Johnswort was absent in control stands, but established and increased significantly (P=0.014) after thinning, and continued to spread at post-thinning year 3 [176].
The information provided in these studies is insufficient to indicate how long St Johnswort seeds retain viability under various field conditions. They do, however, indicate a high likelihood of St Johnswort establishment from buried seed following disturbance (logging, thinning, burning, road construction, etc.). Managers should be prepared for St Johnswort establishment following activities that disturb soil or open the canopy in areas where St Johnswort may have been present or is nearby.
Germination: Considering the large amount of seed produced by St Johnswort, it is important to know when, under what conditions, and what percentage may be expected to germinate. St Johnswort seed dormancy and germination requirements are complex, and seem to be affected by age and source of seed, moisture, temperature, light, nutrients, disturbance, and interactions of these factors.
Several authors have tested for dormancy in St Johnswort seeds, with variable results. Cashmore (1939, as cited by [32]) found St Johnswort seed needed an after-ripening period of 4 to 6 months before it became germinable, and 12 months for it to reach maximum germination capacity. Clark [41] found germination in 9- to 12-month-old St Johnswort seed was erratic and low, with maximum germination of 25%. Sampson and Parker [154] reported germination percentages varying from 5.5% to 63.5% for duplicate seed lots tested over a 40-day period. No indication of the age of these seeds or of the period elapsed since ripening was given. Tisdale and others [178] found large differences in germination (36.2%-84.2%) among sites in Idaho in St Johnswort seed collections of the same year. They then collected St Johnswort seed from 1 site at about 1-week intervals from mid-September to mid-October and tested it for germination within 3 to 6 days of collection. The earliest collections averaged 43% germination, and germination rates increased over later collection dates, reaching a maximum of 58%. Samples tested for germination within a few days of collection took 2 to 5 days longer to begin germinating than did lots stored for 3 to 4 months before testing germination [178]. St Johnswort seed that overwintered in capsules in Nova Scotia, had a lower germination compared to seed stored at 36 °F (2 °C) for 2 years [45]. Reports such as these and the following suggest a dormancy in St Johnswort seeds that may be broken by washing, heat treatment, light, or an after-ripening period.
Field observations by Clark [41], particularly a flush of St Johnswort seedlings in a mature St Johnswort stand after 3 weeks of heavy rain, suggested the presence of a water-soluble inhibiting substance in St Johnswort litter or seed capsules. A germination test was made, using seeds washed with several lots of rainwater. After 7 days, more washed seed germinated (69%) than unwashed seed (34%), washed seed plus leaf extract (44%), and washed seed plus capsule extract (5%). Total germination after 28 days was lower for washed seed plus capsule extract (23%) than for any other treatment (mean 77%). Clark concluded that capsule exudate on St Johnswort seed explained much of the inhibition of germination. Sampson and Parker [154] also reported stimulation of germination after immersion of St Johnswort seed in water for 5 to 20 days, with germination percentages of up to 74%, compared to about 44% germination in control lots. Campbell [32] found that percentage germination of both new (1-6 months old) and old (9 years) St Johnswort seeds was significantly improved (p<0.01) by washing. Crompton and others [45] report a seedling flush often occurs in ground blueberry (Vaccinium myrsinites) fields treated with hexazinone, which may be explained by washing of the seeds by the chemical.
Sampson and Parker [154] report stimulation of St Johnswort seed germination after brief (5-60 minute) exposures to temperatures of 212 °F (100 °C) and 260 °F (127 °C). Germination percentages of up to 81% were obtained with heat treatments, while germination of control lots averaged 44% (see Discussion and Qualification of Fire Effect for more details) [154]. Conversely, hot water (129 °F (54 °C)) immersion for 5 minutes did not break dormancy in St Johnswort seed, and depressed germination of some seed lots. Hot water immersion for 15 minutes killed all seeds from all locations. Seeds were washed in tap water for 5 minutes before hot water immersion [32].
Precise temperature requirements for germination of St Johnswort seeds are unclear, as seed source, age of seed, and exposure to conditions that may release seed dormancy are important variables to consider, and not consistently or comprehensively accounted for in St Johnswort seed germination studies. For example, Campbell [32] found different germination and dormancy characteristics in St Johnswort seed from different sites and different ages. In general, St Johnswort seems to germinate during warm months when adequate moisture is present. Germination may be limited by temperature extremes and promoted by fluctuating temperatures. See these references [32,34,41,174] for further discussion on temperature requirements for St Johnswort seed germination.
While St Johnswort seeds did not germinate in the greenhouse in the dark [174], buried seed may sometimes germinate. Tisdale and others observed limited germination (9% at 0.5 inch, 5% at 1 inch, 1% at 3 inches) from seed buried in the field at various depths. However, no seedlings emerged from 1- or 3-inch (2.5 or 8 cm) depths. A few seedlings emerged from 0.5-inch (1 cm) depth, but none survived [178]. Bosy and Reader [18] found that a covering of grass litter significantly (p<0.05) reduced germination and shoot extension of St Johnswort in the laboratory. Several studies indicate St Johnswort seedling emergence following ground cover or canopy removal and/or soil disturbance [51,147,176]. Campbell [32] found the respective percentage of St Johnswort seedling emergence from under 0, 2, 4, and 8 mm of soil was 57%, 8%, 1% and 0. The author suggests this may be due more to physical impediment than to a lack of light, but this was not tested.
Conclusion/field implications: Clark [41] suggests that the apparent dormancy of St Johnswort seed is determined primarily by the sticky exudate of the seed capsule, which adheres to the seed coat and aids in seed dispersal, and secondarily by the immediate physical environment of the seed in the soil. As a result, germination is delayed until the capsule exudate is washed or worn away, and/or temperature, light, and moisture conditions are appropriate for germination. According to Clark [41] favorable temperature and moisture conditions for germination occur in the field only for short periods of 1 to 2 weeks, and rarely for as long as 4 weeks. Mass germination events, as observed by Sampson and Parker [154] in California, by Walker [189] in Oregon, and by Briese and Clark [22,41] in Australia, may be explained by events and conditions that coincide to favor germination of the previously dormant St Johnswort seed bank.
Seedling establishment/growth: The conditions favorable to St Johnswort seed germination and seedling emergence are apparently exacting. As a result, undisturbed, dense stands of St Johnswort have few seedlings, St Johnswort seedlings only occasionally appear in large numbers [154], and only a small percentage of emergent seedlings establish and grow. For example, less than 1% of 40,000 St Johnswort seedlings that emerged after a stand of mature St Johnswort plants was killed by insects survived after 3 years on a site in Victoria, Australia [41]. Challenges to seedling establishment and growth include St Johnswort seedling size, slow growth rate, intra- and interspecific competition, and moisture stress.
Seedlings of St Johnswort are very small and grow slowly compared to seedlings of many associated species. This slow growth renders St Johnswort seedlings susceptible to competition for light, nutrients, space, and moisture from mature St Johnswort plants and other species [32]. Greenhouse and laboratory experiments indicate that St Johnswort seedling growth is improved when inoculated with arbuscular mycorrhizal fungi, but that the positive growth response is not apparent when seedlings are grown with adult St Johnswort plants [131].
Seedling development and survival in the field were studied in Idaho at 3 sites in 1952 and 8 sites in 1953 [178]. All sites had a well-developed cover of mature St Johnswort plants, along with annual and perennial grasses and forbs. The number of St Johnswort seedlings per 0.1 m² sample plot averaged 57 in 1952 and 71 in 1953. Seedling mortality was extremely high both years, averaging 96% in 1952 and 99% in 1953. The critical period for seedling survival came in late July and in August, when normal precipitation was low and air and surface soil temperatures were at their maximum. Seedlings that did survive the summer drought attained a height of 2 to 4 inches (5-10 cm) above ground, and extended their roots to a depth of 12 inches (30 cm) or more. Some additional mortality of seedlings during their 1st winter was observed, especially on sites with little snow cover. Conspicuous branching of roots began in the 2nd growing season. Variability was high between sites, but had no obvious relationship to vegetation or habitat [178].
Sampson and Parker [154] reported a similar situation in northern California, where most years' seedling survival was nil, but the occurrence of favorable moisture conditions resulted in an "enormous" emergence from seed on occasional years. This results in a population growth pattern where patches of St Johnswort enlarge slowly by vegetative means, and then occasionally expand rapidly through seedling establishment to coalesce and cover large areas [154,178].
Briese [22] tracked population dynamics at 4 qualitatively diverse sites in Australia for 7 years and recorded 1 to 3 mass germination events per site during the 7 years (total of 9 events at 4 sites over 7 years). Seedling survival, however, was less than 10%. Abrupt increases in infestation densities occur as a result of seedling recruitment following conditions favorable for germination. Hence, he says, massive germination is required to substantially increase infestation density and conditions for such events are relatively rare (maximum of 3 in 7 years at 4 sites), while successful recruitment from these is even rarer (once in 7 years at 4 sites). Recruitment recorded at the study sites in 1984 seems to have occurred throughout a wide range of southeastern Australia [22].
Establishment of St Johnswort seedlings is favored by bare soil (e.g. rabbit scratches, burnt areas) and wet summers [41]. Greiling and Kichanan [71] found that St Johnswort seedling emergence was significantly higher (p<0.01) when plant neighbors (little bluestem and old field species) were removed. They also found that insecticide treated plots had nearly double the seedling survival rates as untreated plots, indicating a strong effect of insect herbivores on seedling survival [71]. St Johnswort seedling survival to maturity is low, unless competition is restricted or absent. Consequently, St Johnswort is a weed of disturbed areas and other sites where competition is low (e.g. eucalyptus (Eucalyptus spp.) forests, and hill country in Australia) [32].
Once St Johnswort plants have survived the critical 1st year, they may have an advantage over associated plants as their extensive root system develops, especially if they can grow taller than associated plants [41]. St Johnswort plants more than 1 year old may have extensive horizontal roots [154]. Neither flowers nor seeds are produced by 1st-year St Johnswort seedlings [22,78].
Asexual regeneration: Asexual regeneration of St Johnswort from root fragments, root crown, or lateral root sprouts is reported by many workers, and in Australia some layering has also been observed from fall growth [41,178]. An individual St Johnswort plant spreads via the growth of lateral roots, thereby increasing its area concentrically [34]. Harris [78] says new St Johnswort plants originate at intervals along underground roots that may extend 3 feet (90 cm) or more from the parent plant. In northern Idaho field studies, vegetative spread was due mainly to sprouting from lateral roots a few inches below the soil surface. Tisdale and others [178] observed that vegetative propagation was stimulated by grazing, fire, defoliation (if not too severe), and shallow or very rocky soils. Clark [41] reported similar observations in Australia and stressed the relationship of poor site quality to increased vegetative propagation.
In general, plants propagated vegetatively severed connections with the parent plant fairly soon after new plants established, making it difficult to distinguish crowns developed by vegetative means from those arising as seedlings [41,178]. It was noted, however, that plants that developed from seed formed taproots with axes in a straight line with crowns, while the taproots of vegetatively propagated plants were not so aligned. A study of 6 sites, using these criteria, indicated that 46% of 208 crowns had arisen by vegetative means. It is possible that this percentage might be higher in denser stands and on poorer sites [178]. Population studies in Australia indicate the average percentage of crowns originating vegetatively is often well over 50% [22].
In greenhouse experiments, sections of St Johnswort root sprouted when buried at depths up to 2 inches (5 cm) in moist silt loam soil, but failed to sprout at greater depths. On the 4-inch (10 cm) root sections used, 2 sprouts sometimes developed [178].
St Johnswort is an early successional species as evidenced by its frequent occurrence in disturbed areas. It may occur in the initial stages of plant development after a disturbance (e.g. [20,51,92,154,176,189]), and is also described as a secondary colonizer [75,166]. Its growth habit, persistence and longevity depend on a number of factors including soils, climate, shade, plant community, and site type (forest, grassland, agricultural field), and the presence and vigor of insect herbivores.
Soil fertility and depth may affect the growth habit and longevity of St Johnswort plants as observed in Australia (see Growth habit/stand type). St Johnswort persistence may be affected by elevation (see Site Characteristics), and it may be ephemeral under certain climatic conditions regardless of other site characteristics [22,41,45,154]. The median longevity of individual St Johnswort plants from 4 sites in Australia with varying climatic profiles was 3 to 6 years, with an overall range of 1 to 8 years. Very few St Johnswort crowns survived longer than 8 years. Death of individual crowns was attributed to drought, fire, defoliation by Chrysolina beetles, combinations of these, and senescence [22].
Several authors indicate that St Johnswort requires abundant light for best development. Evidence for this is provided by its occurrence in open grasslands and in open or disturbed forest sites, but not within undisturbed, dense forests, dense brush fields, or under the shade of trees in open forests [78,119,154]. Experimental evidence supports these observations. In a greenhouse test, St Johnswort plants subjected to approximately 50% of full daylight became distinctly pallid and droopy after 10 days, and nearly all of these plants died after 15 days [154]. Typically, where St Johnswort occurs in forested areas, it is often observed along roads and/or forest edges (e.g. [64,138,189]), in open areas within forests (e.g. [12,37,38]), or in early successional stages following fire, logging, or other disturbances (e.g. [39,138,162,178]). For example, on the H.J. Andrews Experimental Forest on the western slope of the Cascade Range in Oregon, St Johnswort was among those species that tended to increase as disturbance level and light level increased [138]. In the Lochsa River area in north-central Idaho, St Johnswort occurs on sites in the western redcedar-western hemlock zone that were previously forested until burned in 1919 and 1934, and have been dominated by seral shrubs for several decades [92,115,134].
Based on evidence of St Johnswort's presence at various stages of succession in some forest types (where data are available), it is unclear how long St Johnswort may persist in disturbed forest sites. In a grand fir/queencup beadlily (Clintonia uniflora) habitat type in the Selway-Bitterroot Wilderness in Idaho, St Johnswort occurred in a 15-year-old stand, but not in a 215-year-old stand [75]. Following the Sundance Burn in the western redcedar-western hemlock zone in northern Idaho, St Johnswort established in postfire year 4 and was last recorded on the site in postfire year 9 [164]. Stickney and Campbell [166] classify St Johnswort as an adventive, off-site colonizer based on data collected in forest communities at the Priest River Experimental Forest in Idaho that were clearcut in 1968 and broadcast burned in 1970. On 2 sites in Douglas-fir/ninebark (Physocarpus malvaceus) communities, St Johnswort established 12 to 15 years after disturbance. Percent cover of St Johnswort fluctuated after establishment and was recorded at 8% and 26% at the 2 sites 20 years after disturbance. In a western hemlock/queencup beadlily community, St Johnswort established at 1% cover 15 years after disturbance, persisted for 1 year and was absent after that [166].
These data suggest that St Johnswort does not persist in mature forest stands, and upholds the statement made in 1959 by Tisdale and others [178] that "serious spread of St Johnswort into 'well-stocked' forest stands has been observed only in open ponderosa pine." However, St Johnswort was found in several stages of succession in unmanaged, naturally regenerated, closed-canopy forests in the Douglas-fir/western hemlock zone of western Oregon, Washington, and northwestern California. Here St Johnswort was associated with young (35-79 yrs) age classes in the Oregon Coast Range, northern California, and southern Oregon; and was present in mature (80-95 yrs) and old growth (200-730 yrs) stands in the Oregon Coast Range, the Oregon Cascade Range, northern California, and southern Oregon [153]. Furthermore, over 80% of St Johnswort infestations in Australia occur in native eucalyptus forests (Shepherd as cited by [22,24]). Evidence presented by Buckley and others [24] indicates that St Johnswort plants growing in shaded sites grow more slowly and produce less fruit but live longer. Additionally, although St Johnswort may not be present in aboveground forest vegetation, viable St Johnswort seed sometimes occurs in forest soils (e.g. [76,114,117]). Consequently, St Johnswort plants may establish and spread following disturbance (see Seed banking).
St Johnswort populations in shaded conditions may be evolving in response to current conditions experienced in their recipient community (sensu [121]), or possibly in response to selection pressures from introduced herbivores. Where Chrysolina beetles are well established for biological control of St Johnswort in Canada, St Johnswort appears to do better in shaded conditions, as the beetles are not shade tolerant. At Fruitvale, British Columbia, St Johnswort and beetle densities in open sites were compared to those in sites receiving about one-half day of sunlight and with places receiving less than one-half day of sunlight. St Johnswort did not flower in the partial shade, and neither St Johnswort nor beetles occurred in densely shaded plots. St Johnswort had the greatest stem density in the greatest shade and the least in open, sunny sites. The more shaded areas also had the fewest Chrysolina hyperici; thus, the shade seems to provide a partial sanctuary for St Johnswort [84]. Conversely, in open eucalyptus woodland and an adjacent clearing in Australia, C. quadrigemina occurred in similar densities in both open and timbered areas. This is unusual since the beetle normally avoids shaded situations and inflicts little damage on St Johnswort plants growing in such conditions [20].
St Johnswort is also a common component of early to mid-successional vegetation on abandoned agricultural land in many areas of North America (e.g. [13,57,60,61,133,154]). On Montague Plain in central Massachusetts, St Johnswort occurred only on plots (100% of them) that were plowed 30-50 years previous [133]. According to Beckwith [13], St Johnswort may be common in the mixed herbaceous perennial stage of old-field succession in Michigan, which usually predominates 11 to 15 years after abandonment from grain crops and 16 to 20 years after abandonment from cultivated and hay fields. Some authors indicate that as old fields succeed to woodlands, St Johnswort goes away as trees and shrubs take over (e.g. Wilson 1943, as cited by [78]). In a study of old-field succession in southeastern Connecticut, St Johnswort was present in the early stages of succession, but was absent from the community 20 to 30 years later, as plant communities succeeded either to young hardwood forest dominated by black cherry (Prunus serotina) and red maple, or vine communities dominated by Oriental bittersweet (Celastrus orbiculata) [60]. Reader [148] presents evidence that suggests that granivory may remove larger seeds of later successional species and leave smaller seeds, such as those of St Johnswort, thus retarding old field succession.
In the parts of North America where St Johnswort is most invasive and considered most problematic, St Johnswort typically established in grasslands that had been severely overgrazed in the early 1900s. At the time that St Johnswort established and spread, these grasslands were no longer dominated by native species, but were typically dominated by nonnative annual grasses and other undesirable plants. Grasslands throughout the interior Columbia Basin, where native perennial grasses have been replaced by nonnative annual grasses such as cheatgrass, are susceptible to invasion by nonnative invasive perennial forb species such as knapweeds (Centaurea spp.) and St Johnswort [26,79,94,95,177,184]. According to Tisdale and others [178], St Johnswort invasion into grasslands in northern Idaho was facilitated by the "depleted condition" of these grasslands, on which the perennial climax dominants had been largely replaced by annual grasses (mainly brome species) and annual forbs. Rapid development and deep penetration of roots of young St Johnswort plants aids in withstanding the critical summer drought period in these areas, and St Johnswort's deep and extensive root system may allow it to outcompete the annuals for water and nutrients [178]. Similarly, St Johnswort commonly invaded annual grassland sites in northern California that were once dominated by perennial grasses [93]. According to Sampson and Parker [154], St Johnswort shades out the shorter grasses and depletes moisture in the upper soil layers to the point of excluding other vegetation. California oatgrass (Danthonia californica) is among the last of the grasses to be replaced by St Johnswort, while winter annuals tend to persist as St Johnswort increases in density. A late successional St Johnswort invasion is described as a dense stand of St Johnswort with an understory of winter annuals [154]. No definite data as to the longevity of St Johnswort in grasslands exist; however, Harris [78] cites observations of 40- to 50-year-old St Johnswort infestations (as of 1951) on California rangeland.
St Johnswort populations were severely impacted, and successional trajectories further altered, in some areas following the North American introduction of biological control agents for St Johnswort [31,160,177]. These reductions were followed by increases of different plants in different areas. In the Interior Columbia Basin, successful biological control of St Johnswort was followed by a return to annual grass dominance [26,177]. Many pastures in Oregon that were once infested with St Johnswort became infested with tansy ragwort (Senecio jacobaea) after St Johnswort was reduced by biological agents [43]. In northern Idaho, the overall abundance of St Johnswort fluctuates around 3% of that present in 1948. As yield and frequency decreased in St Johnswort, annual forbs and grasses increased, with annual bromes being most common, along with foxtail fescue (Vulpia myuros), and the relatively new arrival of medusahead. Perennial forbs and grasses increased to a lesser extent. Natural recovery of bluebunch wheatgrass in these areas is thought to be inhibited by inadequate seed source, competition from annual grasses, and continuing heavy grazing on many sites [177]. Campbell and McCaffrey [31] found that where St Johnswort is suppressed by biocontrol insects in northern Idaho, replacement vegetation is dominated by annual grasses and weedy forbs such as knapweeds and field bindweed (Convolvulus arvensis). Spotted knapweed (Centaurea maculosa) has largely replaced St Johnswort throughout the northernmost areas of Idaho. At 1 site yellow starthistle (C. solstitialis) succeeded medusahead, which invaded after St Johnswort was initially reduced by biocontrol agents (personal communication by M. Hironaka as cited in [31]). On annual grasslands in northern California, St Johnswort was reduced to less than 1% of its former occurrence 10 years after establishment of biocontrol insects. This reduction was accompanied by a concurrent increase in perennial grasses (mainly California oatgrass) in Humboldt County, and an increase in winter annual grasses, legumes, and other forbs in other areas. No major increases of other invasive species were reported at the time (1959), although yellow starthistle and medusahead were both present on several sites [93]. It is unclear how biological control insects of St Johnswort may affect succession in other areas where the insects have less total impact on St Johnswort populations.
The currently accepted name for common St Johnswort is Hypericum perforatum
L. It is a member of the mangosteen or St Johnswort family (Clusiaceae)
[67,69,98,99,100,199]. Some authors treat the
St Johnswort family (Hypericaceae) separately
(e.g. [89,90,109,127,145,152,193]). Other authors use the
family name Guttiferae (e.g. [168,187]).
The Flora Europaea recognizes several varieties and hybrids of Hypericum perforatum
in Europe [173]. Earlier
treatments identify the variety Hypericum perforatum var. angustifolia
in Australia [34]. It is also suggested that varying characteristics in
St Johnswort simply represent a variable taxon, and no classification at the varietal level is
recommended [35]. No hybrids are known to occur in Australia [34] or North America [45].
Hypericum perforatum, tamién conocida como pericóno flor de la virxe, ye la especie más abondosa de la familia de les gutíferas (Guttiferae) o hipericacees (Hypericaceae).
Ye una planta común nos terrenes de baxa y mediu altor. Alcuéntrase práuticamente en toa Europa, hasta l'este de Rusia, y aclimatóse en numberoses partes del mundu: China, Australia, Norte d'África y América.
Hipócrates encamentar como remediu refrescante y antiinflamatoriu.
Dioscórides escribi lo siguiente (cola ortografía de les traducciones antigües): El Hyperico, llamáu Androsemo por unos, por otros Corio, y por otros Camepytis, que quier dezir Pinillo, porque la so resina güel a resina de pinu, ye un matu ramosu, roxeta y de un palmo d'alta, que produze les fueyes como l'arruda, y de flor mariella: la qual estregada ente los deos, resuda un liquor asemeyáu a la sangre, de do vieno llamase Androsemo que significa sangre humano. Naz el hyperico en llugares cultivaos y aspros. Tien facultá de mover la orina y, aplicáu por baxo, provoca'l menstruo. Bebíu con vinu, estermina les tertianas y les quartanas. La so semienta bevida por una quarentena de díes, cura la sciática y les fueyes cola semienta aplicaes en forma de emplastro, sanan les quemadures del fueu[1]
Ye un parrotal orixinariu d'Europa, que se naturalizó n'América. Los pétalos de la flor son de color mariellu doráu, con pequeños llixos negros nos sos cantos, l'apellativu llatín perforatum provién de les pequeñes perforaciones -en realidá son bolses d'aceite esencial- que pueden trate al bellume en caúna de les fueyes d'esta planta. Son el doble de llongures que los sépalos. Una peculiaridá d'esta yerba ye que, al entartallar ente los deos dalguna de los sos hojitas, dexa un llurdiu na piel la so cazumbre anaranxada.
N'Australia y nos Estaos Xuníos considerar como una maleza o una especie invasora y se'l combate per mediu de controles biolóxicos tales como los escarabayos del xéneru Chrysolina, que s'especialicen nesta planta.[2][3]
Hypericum perforatum ye una planta melecinal con múltiples aplicaciones. Por casu, la so aplicación tópica sirve p'acelerar la cicatrización de les firíes.
Sicasí, les propiedaes d'esta yerba que más atraxeron a los investigadores venceyar col so usu tradicional pal tratamientu de la depresión leve a moderada y l'ansiedá.[4] Esta indicación foi validada nes últimes décades poles axencies de salú de dellos países como Alemaña, onde foi incluyida na farmacopea oficial, y prescríbese llargamente con esi propósitu terapéuticu.[5]
Cuando'l hipérico utilízase como melecina fitoterapéutico, xeneralmente alminístrase en forma d'estractos estandarizaos, con concentraciones fixes de los principios activos a los cualos atribúyense los efeutos farmacolóxicos; envalórase que'l más importante d'estos ye la hipericina, anque estudios recién reporten una mayor actividá de la hiperforina.[6][7] Esta conclusión básase fundamentalmente nun ensayu con resultancia negativa lleváu a cabu pol Centro Nacional de Medicina Complementaria y Alternativa de los Estaos Xuníos.[8][9][10][11]
Pa esti fin (tratamientu de la depresión), la yerba de San Juan puede consiguise en diverses presentaciones: como yerba, como gragea o cápsula, en bolses de té o en tintures.
El hipérico ye un potente inductor enzimáticu del citocromo P450 (isoenzima CYP3A4) y posiblemente tamién de la glicoproteína P. Puede producir interacciones con otres sustances, tales como la digoxina o anticoagulantes orales.[12]
Coles mesmes, hanse documentáu casos de refuga de tresplante de corazón en dos pacientes que combiaron el tratamientu inmunosupresor (ciclosporina) y tomar de hipérico. En dambos casos, tou paez indicar qu'el hipérico provocó un descensu de les concentraciones plasmátiques de ciclosporina per debaxo del nivel terapéuticu, lo que causó'l refugu del ensiertu. Un estudiu formal posterior demostró qu'el hipérico amenorga la concentración plasmática de indinavir.[12]
Por cuenta de la importancia d'estos datos, paez prudente nun acomuñar tomar de hipérico cola de nengún fármacu de metabolismo hepáticu.[12] Vease l'apartáu Tabla d'interacciones con diverses sustances.
Hypericum perforatum puede interferir cola absorción de fierro y otros minerales. El responsable de la tosicidá d'esta planta, ye la hipericina, tratar d'un pigmentu heliantrono de color coloráu encarnáu y fluorescente que s'atopa nos llurdios negros esvalixaes na superficie de les fueyes y pétalos florales del vexetal. Esti compuestu alcuéntrase presente na planta en tou momentu y persiste cuando s'ensuga o ye henificada[13]
La hipericina ye la responsable de la fototoxicidad, dende l'antigüedá, reparáronse trestornos de la piel n'animales que comieren d'esta planta. Namái en casos graves por sobrealimentación, reparáronse convulsiones epiléptiques, crisis hemolíticas o muerte del animal. De resultes de la fotosensibilización tamién se reparen trestornos hepáticos ya ictericia, de la que les partes pocu pigmentaes de la piel pueden necrosarse o esprendese, dando llugar a repulgos de sanamientu bien lentu. Per otra parte, los animales femes que comen d'esta planta amosaron una menor secreción láctea. En persones que tomaren esta planta y que s'espongan al sol darréu, puede presentase una pigmentación discreta de la piel (eritemas) o pruyiciu.[14]
Hypericum perforatum demostró ser solo llixeramente tóxicu tres una única dosis oral o intraperitoneal. A nivel esperimental, la DL50 fueron les siguientes:
Especie Vía d'alministración DL50 (mg/kg) Aguarón Oral 5000 Oral 5000 Aguarón Intraperitoneal 1780 Intraperitoneal 1000L'alministración oral repitida del estractu de Hypericum perforatum a dosis de 300, 900 y 2700 mg/kg de pesu corporal diarios n'aguarones y perros mientres un periodu de 26 selmanes nun provocó cambeos específicos de la sustanza. A dosis cimeres a 900 mg/kg pesu corporal diarios desenvolviéronse signos inespecíficos d'intoxicación: pesu amenorgáu, llixeros cambeos nel hemograma, cambeos na química clínico y morfolóxicu los cualos, causaos pola alta dosis, indicaron un dañu leve, por sobrecarga, nel fégadu y reñones.
Los estudios llevar a cabu con aguarones y coneyos y nun hubo evidencia nenguna de cambeos teratogénicos hasta dosis asitiaes nel rangu de la tosicidá materna. Los efeutos embrio-fetotóxicos, apaecieron a dosis tóxiques pa la madre y reparóse:
estudiu de fertilidá con aguarones, nun s'amosaron efeutos sobre les mesmes. Cabo destacar que, nos aguarones, la hipericina atropar na lleche pudiendo llegar a algamar concentraciones cimeres a les del plasma maternu, pero debíu al ampliu marxe de seguridá qu'amuesa la hipericina ye improbable que la cantidá inxerida cola lleche represente peligru dalgunu pal neñu anque nun se dispon d'información abonda no relativo a la lactancia. Como precuru xeneral, nun se debe emplegar nin nel primer trimestre del embaranzu nin mientres la lactancia.
Lleváronse a cabo estudio de mutagenicidad in vitro ya in vivo concluyendo la inesistencia de riesgu mutagénico pal home con estractu de Hypericum.
Sobre'l potencial carcinogénico nun se tienen abondos datos como pa concluyir la esistencia o non de potencial[15]
La fotosensibilidad ye'l principal riesgu de tosicidá, siendo de tipu primaria cuidao que se produz por absorción dixestiva de la planta, pero en rares ocasiones pueden apaecer trestornos gastrointestinales, cansanciu o intranquilidá[16]
Como se dixo primeramente, la hipericina ye'l causante de la fotosensibilización (un tipu de reacción alérxica) nel ganáu ovín provocando un exantema o la enfermedá conocida como St. Johnsword. Estos pigmentos de la planta, son inxeríos n'ocasiones de manera abondosa polos ovinos en llendo. Darréu lleguen a la piel dende la riega circulatoria onde aferruñen los aminoácidos, histidina, triptófano y tirosina, modificando asina la estructura y permeabilidá de les célules. La gravedá va depender de la dosis, de la duración de la ingesta lo mesmo que de la intensidá de la radiación solar.
La clínica apaez en zones non pigmentaes nin revistíes de llana, esto ye, en cabeza, oreyes, estremidaes y mama onde apaecen inflamaciones, sobremanera na cabeza recibiendo'l nome de cabeza enchida”, y nes zones de la piel, ésta, va tar enchida, caliente y edematosa; esta patoloxía, se continua cola exudación d'un líquidu seroso y desprendimientu del epiteliu. Como mecanismu de defensa, los animales traten d'atopar la solombra. N'etapes posteriores, pueden necrosarse partes de la piel afeutada según les puntes de les oreyes.
N'ocasiones, anque nun ye tan frecuente, puede apaecer:
Destacar que les intoxicaciones por Hypericum prodúcense, fundamentalmente, en animales ovinos mientres la ingesta de la campera. Suelen ser los animales nuevos los más afeutaos, por cuenta de la competencia pol alimentu na campera según la falta d'esperiencia d'estos postreros a la d'escoyer los alimentos non tóxicos.
Les intoxicaciones infantiles por Hypericum, según el Serviciu d'Información Toxicológica, prodúcense dacuando, cuidao que estos pueden llevase a la boca los fitofármacos que contengan l'estractu de Hypericum que tomen los sos familiares adultos[18]
L'Axencia Española de la Melecina considera necesariu alvertir que los productos qu'inclúin na so composición al Hypericum perforatum, tienen la capacidá de interaccionar con distintes melecines. Les interacciones son productu de la capacidá inductora del Hypericum perforatum sobre ciertes isoenzimes del citocromo hepáticu P450. De resultes puede apaecer un amenorgamientu de les concentraciones plasmátiques y una perda del efeutu terapéuticu; teniendo en cuenta esti mecanismu de la interacción, al dexar d'alministrar Hypericum perforatum puede tamién provocar un aumentu de los niveles sanguíneos de delles melecines cola consiguiente apaición de tosicidá, siendo especialmente importante en melecines d'estrechu marxe terapéuticu. La interacción colos IMAO ye d'especial importancia por cuenta de que conduz a una situación peligrosa porque puede dar llugar a crisis hipertensivas. Asocede lo mesmo nel casu d'una ingestión d'alimentos ricos en tiramina pola ingestión d'esta planta.
Un exemplu concretu ye la interacción colos inhibidores de la proteasa nos cualos produzse un amenorgamientu significativu de les concentraciones plasmátiques de los mesmos pola inducción de la isoenzima 3A4 del citocromo P450. Como resultáu d'ello, nun s'algamar concentraciones plasmátiques terapéutiques d'esti tipu de fármacu pudiendo desenvolvese resistencies y falta d'eficacia del tratamientu.
Fármacu Efeutu delhipérico sobre'l fármacu
Conducta a siguiren pacientes en tratamientu con hipérico
Anticonvulsivantes (carbamazepina, fenobarbital, fenitoína) Amenorgamientu de los niveles plasmáticos con riesgu de convulsiones Midir los niveles plasmáticos del anticonvulsivante y amenorgar gradualmente l'alministración de hipérico, afaciendo la dosis del anticonvulsivante conforme a los niveles que se vaigan llogrando Antidepresivos inhibidores selectivos de la recaptación de serotonina (citalopram, fluoxetina, paroxetina y nefazodona) Medría de los efeutos serotoninérgicos con aumentu de la incidencia de reacciones adverses Atayar l'alministración de hipérico Ciclosporina Midirlos niveles plasmáticos de ciclosporina y amenorgar gradualmente l'alministración de hipérico, afaciendo la dosis de ciclosporina conforme a los niveles que se vaigan llogrando
Anticonceutivos orales Amenorgamientu de los niveles plasmáticos con riesgu d'embaranzu ensin esperar y hemorraxes intermenstruales Atayar l'alministración de hipérico Digoxina Midirlos niveles plasmáticos de digoxina y amenorgar gradualmente l'alministración de hipérico, afaciendo la dosis de digoxina conforme a los niveles que se vaigan llogrando
Inhibidores de Proteasa (indinavir, nelfinavir, ritonavir, saquinavir) Amenorgamientu de los niveles plasmáticos con posible perda de supresión de VIH Atayar l'alministración de hipérico y la carga viral de VIH Inhibidores de transcriptasa inversa non nucleósidos (efavirenz, nevirapina) Amenorgamientu de los niveles plasmáticos con posible perda de supresión de VIH Atayar l'alministración de hipérico y la carga viral de VIH Teofilina Midirlos niveles plasmáticos de teofilina y amenorgar gradualmente l'alministración de hipérico, afaciendo la dosis de teofilina conforme a los niveles que se vaigan llogrando
Triptanes (sumatriptan, naratriptan, rizatriptan, zolmitriptan) Medría de los efeutos serotoninérgicos con aumentu de la incidencia de reacciones adverses Atayar l'alministración de hipérico Warfarina y acenocumarol Amenorgamientu del efeutu anticoagulante y necesidá d'aumentar la dosis de warfarina/acenocumarol Midir el INR y amenorgar gradualmente l'alministración de hipérico. Afaer la dosis de anticoagulante en función del INRL'alministración de los estractos d'esta yerba ye motivu d'alderique. Anque esiste evidencia llindada que suxure la so eficacia y seguridá, nun foi evaluada sistemáticamente no que fai a la incidencia d'efeutos secundarios ya interacciones con otres drogues, colos riesgos qu'esto trai. Aun así, méntase que, nel casu de dellos tratamientos, amenorga'l so efeutu como nos tratamientos pa persones con VIH.
Considerar un axente primariu de la fotosensibilización en bovíns, nos cualos la hipericina atropar nel texíu subcutáneo y reacciona cola lluz solar, y provoca cuadros d'inflamación de la dermis, especialmente de les partes menos pigmentaes, que pueden esprendese del animal.
Esta especie conocer con numberosos nomes comunes n'español: amnica, cientoenrama, corazón de venáu, corazoncillo, corión, espantadiablos, yerba de l'agua, yerba del sangre, yerba de les feríes, yerba de les machacauras, yerba de San Juan, yerba militar, hipericón, hipericón oficinal, hipérico, hipérico covanosu, hipérico común, furada, perforata, pericó, pericón, pericón mariellu, pericón común, pericón montés, pericu, pericote, periquitu, San Juan, sanxuanera, sanjuanes, san juanes, sanjuanines, té cantu, trescalar, tresflorina, yerba de San Juan, yerbuca de San Juan.[19]
Hypericum perforatum describióse por Carlos Linneo y espublizóse en Species Plantarum 2: 785. 1753.[20]
Hipérico: nome xenéricu que remanez del griegu hyperikon ("sobre les imáxenes" o "percima d'una apaición"). Pa dalgunos, el nome fai referencia a la propiedá que se-y atribuyía de faer fuxir a los malos espíritos y les apaiciones; solíen colgar flores d'esta planta sobre les imáxenes relixoses el día de San Juan. Pa otros, les glándules de les sos pétalos paecen formar imáxenes (a esti fechu dióse-y muncha importancia na Edá Media, yá que yera utilizáu nos esconxuros poles sos virtúes cabalístiques).
perforatum: epítetu que se debe a les glándules d'aceite asitiaes nes sos fueyes y sépalos que-y dan a la planta un aspeutu furáu, si reparar al bellume.[1]
Hypericum perforatum foi designáu a lo llargo de la hestoria con distintos nomes científicos, consideraos sinónimos:
.
Esta páxina forma parte del wikiproyeutu Botánica, un esfuerciu collaborativu col fin d'ameyorar y organizar tolos conteníos rellacionaos con esti tema. Visita la páxina d'alderique del proyeutu pa collaborar y facer entrugues o suxerencies. Hypericum perforatum, tamién conocida como pericóno flor de la virxe, ye la especie más abondosa de la familia de les gutíferas (Guttiferae) o hipericacees (Hypericaceae).
Adi dazı (lat. Hypericum perforatum),[1]pəncə,[2] və ya dəlikli dazıotu – dazı cinsinə aid bitki növü.[3]
Adi dazı üfüqi istiqamətdə uzanan incə kökümsova və güclü inkişaf etmiş kök sisteminə malik, dikduran gövdəli çoxillik ot bitkisidir. Hündürlüyü 30-60 sm, bəzən də artıq olur. Gövdəsi iki qabırğalıdır. Yarpaqları saplaqsız olub, gövdə üzərində qarşı-qarşıya düzülürlər, ovalşəkilli, bir qədər uzunsov və tam kənarlıdırlar. Yarpaqlarının üzərində çoxlu vəzilər vardır. 5 kasa və 5 taç yarpaqlarından ibarət olan qızılı-sarı rəngli çiçəkləri qalxanabənzər süpürgə çiçək qrupu əmələ gətirir.
Ləçəklərinin kənarlarında nöqtə şəkilli qırmızı rəngli vəzilər yerləşir. Meyvəsi yumurtavari, üç yuvalı qırmızımtıl qəhvəyi rəngli çoxtoxumlu qutucuqdur. Qutucuğun hər yuvasında çoxlu sayda, tünd qəhvəyi rəngli xırda (1 mm-ə yaxın) toxumlar olur. Çiçək və meyvəsində narıncı rəngli hiperisin piqmenti var. Bu piqment dəriyə toxunduqda əvvəlcə narıncı rəngli ləkə kimi görünür, sonra getdikcə tədricən tündləşərək qəhvəyi rəng alır. Adi dazı iyun ayından başlayaraq avqusta qədər çiçəkləyir. Meyvələri avqust-sentyabr aylarında yetişir.
Əsasən meşə kənarlarında, kolluqlarda, əkin yerlərinin kənarlarında, becərilməyən yerlərdə bitir. Meşə yolları və sahələrin ətrafında alaq otu kimi gözə dəyir. Avrasiyada Atlantik okeanı sahillərindən Sibir, Monqolustan və Çinə qədər ərazidə geniş yayılmışdır. Şimali Afrikada, Kanar və Azor adalarında rast gəlinir. Bəzi növləri Avstraliya, Yeni Zelandiya, Yaponiya, Şimali və Cənubi Amerikaya gətirilmib yayılmışdır. Azərbaycanın bir çox rayonlarında yayılıb. Respublikamızda ehtiyatı boldur.
Tibbi məqsədlə adi dazı bitkisinin yerüstü hissəsindən (Herba Hyperici) istifadə edilir. Bitki xammalı intensiv çiçəkləmə dövründə yerdən 8-10 sm hündürlükdə kəsilərək yığılır. Kölgədə, yaxud quruducularda 35-40° S temperaturda qurudulur. Düzgün qurutduqda bitkinin rənki dəyişilmir və təzə bitkidə olduğu kimi xoş balzamik ətrə malik olur. Qurudulmuş xammalın öz keyfiyyətini saxlama müddəti 3 ildir.
Adi dazı çoxlu bioloji aktiv maddələrə malikdir. Onun tərkibində fotoaktiv antrasen törəmələri (hiperisin—0,4%, psevdohiperisin, protopsevdohiperisin və s), flavon birləşmələri (hiperozid—0,7-1%, rutin, kversitrin, izokversitrin, mirisetin və kversetin), efir yağı — 0,1-0,25% (terpenlər, seskviterpenlər və izovalerian turşusunun mürəkkəb efirləri), aşı maddələr (10%-ə qədər), qətranlar (10%-ə qədər), saponinlər, antosian, seril spirti, alkoloidlərin izi, karotin (55 mq%), nikotin turşusu, askorbin turşusu (80-120 mq%), xolin (34 mq%), P vitamini, PP vitamini, tokoferol və s. aşkar edilmişdir.
Rekenerativ, iltihab əleyhinə, yarasağaldıcı.
Adi dazı geniş farmakoloji təsir spektrinə malik bitkidir. Müəyyən edilmişdir ki, adi dazının flavonoidləri qan damarlarının, öd yollarının və bağırsaqların saya əzələlərinə spazmolitik təsir göstərir. Petkov (1988) Leclerc-ə istinad edərək, adi dazının antiseptik xassəyə malik olduğunu qeyd edərək onu yarasağaldıçı kimi tətbiq etməyi məsləhət körür. Onun fikrincə, adi dazı yerli anesteziyaedici və iltihab əleyhinə təsirlərə malikdir.
Eksperimental olaraq adi dazıdan ekstraksiya nəticəsində alınmış karotin, tokoferol və ali spirtlərdən ibarət qatışığın iltihabпötürücü təsir пöstərməsi müəyyənləşdirilmişdir.
Adi dazının preparatları büzücü, iltihabпötürüçü, antiseptik təsirlərə malik olmaları ilə yanaşı, reпenerasiya proseslərini də tənzimləyirlər.
Adi dazının çıxarışları ürək əzələlərinin yığılma amplitudasını artırır, qan təzyiqini azça yüksəldir, sinir sisteminə antidepressiv təsir пöstərir. Onun qalen preparatları qastrit, mədə-bağırsaq yaraları, enterokolit, öd yollarının diskineziyası, xolesistit, öd daşı, hepatit, babasil, sistit, stomatit, parodontoz, gingivit, faringit və s. xəstəliklərin müaliçəsində geniş istifadə edilir. Adi dazının preparatları zəif toksiki təsirə malikdirlər. Lakin fəsad vermirlər.
Adi dazı həlimindən yoğun bağırsağın rentgenoloji müayinəsində də istifadə olunur. Bu zaman barium qatışığına, 15,0:100,0 nisbətindən hazırlanmış dazı həlimi qarışdırılır. Bu, bir tərəfdən qarışırın bağırsaqda asan hərəkətini təmin edərək müayinə müddətini azaldır, digər tərəfdən isə bariumun özlülüyünü azaldaraq selikli qişanın relyefinin daha dəqiq alınmasına imkan yaradır. Adi dazıdan otolarinqoloji təcrübədə də istifadə olunur. Belə ki, bitki xammalından (1:5 nisbətində 40°-li spirtdə) alınmış cövhər xroniki iltihablı otitdə ya damçı şəklində, yaxud trunda vasitəsilə qulaq keçəçəyinə daxil edilir. Bu qayda ilə hazırlanmış cövhərdən tonzillit, angina, gingivit və stomatitdə (1 stəkan suya 30-40 damcı) qarqara etmək üçün istifadə olunur. Adi dazı fotosensibilizəedici maddə kimi, insanda Günəş işığına qarşı həssaslığı yüksəltmək qabiliyyətinə malikdir. Sokolov və Zamotayev bu xassənin, dazı bitkisinin tərkibindəki hiperisin piqmenti ilə əlaqədar olduğunu qeyd edirlər. Adi dazının qatılaşdırılmış ekstraktından vitiliqoda piqmentsizləşmə nəticəsində dəridə əmələ gələn ağ ləkələri yox etmək üçün istifadə edilir. Bitki xammalından antibakterial təsirə malik "Novoimanin" (Novoimaninum) preparatı alınmışdır.
Bolqarıstanda bitkinin yerüstü hissəsindən qaraciyər və öd kisəsinin, o cümlədən həzm traktının xəstəliklərində büzücü və iltihabgötürücü maddə kimi istifadə olunur. Yara, podaqra, işias, revmatizm, vərəm və babasil xəstəliklərinə qarşı məsləhət görülür.
Fransada adi dazı otundan həm diuretik, həm ürək fəaliyyətini tənzim edən, həm də toxumaların regenerasiyasını tənzim edən maddə kimi istifadə edirlər.
Polşada ondan mədə-bağırsaq xəstəliklərində qankəsici və yarasağaldıçı maddə kimi, habelə qəbizlik hallarında, nevralgiyada, baş ağrılarında, yuxusuzluqda istifadə edilir.
Rus xalq təbabətində adi dazı revmatizm, işias, podaqra, ağçiyərlərin vərəmi, daxili qanaxmalar, babasil, qaraciyər xəstəlikləri, çiban və digər iltihabi proseslərin müalicəsi üçün geniş istifadə olunur.
İbn Sina adi dazının, oturaq siniri iltihabını götürdüyünü, güclü sidikqovucu və yarasağaldıcı effektlərə malik olduğunu qeyd etmişdir.
Adi dazı xammalından müxtəlif üsullarla çıxarışlar aparılır:
Çini bir qaba lazım olan qədər dazı çiçəkləri doldurub, ürtünə onu örtənə qədər zeytun yağı tökülür. Qabın ağzı qapaqla örtülərək su hamamında 6 saat dəmlənir. Bundan sonra su hamamından çıxarılır. Ağzı açılmadan, otaq temperaturunda soyudulur və süzülür. Bu müddət ərzində zeytun yağı dazının keyfiyyətini almış olur. Onun rəngi qırmızımtıl-qonur rəngə çalır və spesifik aromat kəsb edir. Bu yağ mədə-bağırsaq yaralarında, qastritdə, öd yollarının iltihabında çox yaxşı təsir göstərir. Ondan gündə bir dəfə, səhər-səhər ac qarına, bir xörək qapşığı qəbul edilir.
Xırdalanaraq toz halına salınmış dazı otundan iki xörək qaşığı qədər götürərək 0,5 l suya tökülür, beş dəqiqə qaynatdıqdan sonra süzgəcdən keçirilir. Gündə 3-4 dəfə (hər dəfə 100 ml) yeməkdən 20-30 dəqiqə əvvəl isti halda qəbul edilir.
Üç xörək qaşığı xırdalanmış dazı otu üzərinə 250 ml qaynar su töküb, iki saat dəmə qoyulur. Sonra süzülür. Gündə üç dəfə, hər dəfə 70-80 ml, yeməkdən əvvəl qəbul edilir.
Dazı həliminin hazırlanması. 10 q xırdalanmış adi dazı xammalı üzərinə 200 ml qaynar su töküb ağzını qapaqla örtdükdən sonra 30 dəqiqə ərzində su hamamında saxlanılır. Su hamamından çıxardıqdan 10 dəqiqə sonra süzülür. Alınmış həlimin üzərinə qaynanmış su əlavə etməklə əvvəlki həcmə (200 ml) çatdırılır. Ondan gün ərzində 4-5 dəfə, hər dəfə bir xörək qaşığı qədər qəbul edilir.
Qeyd olunan üsullardan əlavə, adi dazı bir çox dərman bitkiləri yığınlarının da tərkibinə daxildir.
El pericó[1] o herba de Sant Joan[2] (Hypericum perforatum) és una planta herbàcia de la família de les clusiàcies, abans anomenada Hipericàcies. Aquesta planta està present a bona part d'Europa, Àfrica, l'Àsia occidental i zones temperades de la resta del món, deserts i regions antàrtiques. S'importa de l'antiga URSS, Bulgària, Hongria i Romania. Es troba distribuïda àmpliament als Països Catalans. També és coneguda com a "berbena/berbenes de Sant Joan", "centaura groga", "corassonillo", "diablots", "dragó", "flor de San Joan", "flor de cop", "flor de sant/Sant Joan", "flor de sant/Sant Pere", "foradada", "herba de cop", "herba de fer oli de cop", "herba de les ferides", "herba del cop", "herba de les bruixes", "herba de les ferides", "herba de l'oli de cop", "herba dels cops", "herba del pericó", "herba de sant/Sant Joan", "herba foradada", "herba santjoanera", "hipericó", "hipèric foradat", "inflabou", "milifulla groc", "oli de cop", "pericó", "pericó foradat", "pericó groc, "pericot", "periquet", "santaura groga", "Sant Joan/santjoan", "santjoans", "transflorina", "trasflorina", "trescam/trescalam", "tresflorina", "tresflorina comuna", "tresflorina vera".[3] [4]
El terme Hypericum ve del grec "hyperikon", que significa 'per sobre d'una aparició'. Es diu perforatum perquè les glàndules d'oli situades a les fulles i als sèpals donen a la planta un aspecte perforat. Anteriorment es creia que el nom feia referència a la propietat que hom li atribuïa de fer fugir els esperits dolents i les aparicions.
És una espècie herbàcia perenne de 30 a 60 cm d'alçada. Presenta un rizoma que es fa més prim prop del final de la planta, i té una Arrel axonomorfa i fusiforme d'on surten tiges llenyoses de la base de color verd-groguenc a vermellós, erectes i cilíndriques amb dues línies prominents al costat. Les fulles (1,5-4 cm) són lanceolades, oposades, de marge sencer, sèssils i amb pigues translúcides que són glàndules plenes d'oli essencial i travessen la fulla del revers a l'anvers. A l'anvers de les fulles es veu un nervi mig molt prominent. Als cantons d'aquestes fulles es poden observar uns petits punts glandulosos foscos. Les flors són pentàmeres, estrellades,hermafrodites, disposades en cimes dicotòmiques, reunides en una panícula terminal. El calze té 5 sèpals d'apendix puntxegut, llisos, amb el marge serrat a la punta i amb glangules clares i obscures als dos costats del nervi mitjà. Els 5 pètals són grocs i també porten glàndules secretores als cantons. L'androceu es compon d'estams molt nombrosos i definits, amb filaments i anteres grogues amb un puntet negre molt perceptible i amb un pistil que remata amb tres estils molt ben individualitzats. El gineceu és súper amb 2 o 3 carpels soldats. La inflorescència és un corimbe i el fruit una càpsula ovoide de 3 càmares que poden ser ovals o triangulars. Les llavors són cilíndriques d'1-3 mm de longitud i amb la superfície coberta de petites berrugues i de color marró fosc o negre.
Es troba en llocs pocs humits, principalment als marges dels camins o carreteres, prades, tanques, ribes i llocs assolellats. Pot aparèixer a prop de rius o rierols. Es troba en terrenys de mitjana i baixa alçada. Té un complex cicle vital que inclou la maduració i la reproducció sexual. Les pluges d'estiu afavoreixen el seu creixement.
S'utilitza tota la planta des del punt de vista medicinal però sobretot les fulles i les flors.
El pericó té efectes secundaris com molèstia gastrointestinal, hiperpigmentació i fotosensibilització, dermatitis, urticària, fatiga, ansietat, mareigs, problemes al fetge, dolor de cap i disfunció sexual (inclou la impotència). A més a més, té moltes interaccions amb altres medicaments com alguns anticonceptius, antidepressius, antiinflamatoris, analgèsics, fàrmacs antiretrovirals, antibiòtics i anticoagulants que provoca la pèrdua de l'efecte d'aquests i toxicitat.
Han disminuït el seu consum perquè no hi ha laboratoris que tinguin la patent per estudiar els seus efectes.
Cal avisar al vostre metge o doctor que esteu prenent aquesta planta pels efectes secundaris que pot ocasionar.
A l'edat mitjana es cremava en les cases en què es creia que hi havia entrat el Dimoni, fins a tal punt que era coneguda com a Fuga daemonium (espantadimonis). Es diu que cura la melancolia i atrau l'amor. En la cultura celta, es deia que les fades dolentes, els follets i mags de males intencions no entrarien mai en una casa on les seves finestres estiguessin protegides per ramets d'aquesta planta.
Un dels noms populars d'aquesta planta és herba de Sant Joan i és degut al fet que la seva floració es dóna al voltant del 24 de juny juntament amb la festivitat de la nit de Sant Joan.
Flor Hypericum perforatum
Pericó
Flor del pericó
Hypericum perforatum
El pericó o herba de Sant Joan (Hypericum perforatum) és una planta herbàcia de la família de les clusiàcies, abans anomenada Hipericàcies. Aquesta planta està present a bona part d'Europa, Àfrica, l'Àsia occidental i zones temperades de la resta del món, deserts i regions antàrtiques. S'importa de l'antiga URSS, Bulgària, Hongria i Romania. Es troba distribuïda àmpliament als Països Catalans. També és coneguda com a "berbena/berbenes de Sant Joan", "centaura groga", "corassonillo", "diablots", "dragó", "flor de San Joan", "flor de cop", "flor de sant/Sant Joan", "flor de sant/Sant Pere", "foradada", "herba de cop", "herba de fer oli de cop", "herba de les ferides", "herba del cop", "herba de les bruixes", "herba de les ferides", "herba de l'oli de cop", "herba dels cops", "herba del pericó", "herba de sant/Sant Joan", "herba foradada", "herba santjoanera", "hipericó", "hipèric foradat", "inflabou", "milifulla groc", "oli de cop", "pericó", "pericó foradat", "pericó groc, "pericot", "periquet", "santaura groga", "Sant Joan/santjoan", "santjoans", "transflorina", "trasflorina", "trescam/trescalam", "tresflorina", "tresflorina comuna", "tresflorina vera".
Planhigyn blodeuol lluosflwydd a dyf yng ngorllewin Ewrop ydy Eurinllys trydwll sy'n enw gwrywaidd. Mae'n perthyn i'r teulu Hypericaceae. Yr enw gwyddonol (Lladin) yw Hypericum perforatum a'r enw Saesneg yw Perforate st john's-wort.[1] Ceir enwau Cymraeg eraill ar y planhigyn hwn gan gynnwys Eurinllys Trydwll, Candoll, Cantwll, Eurinllys Tyllog, Llysiau loan, Tarfwgan, Ysgol Fair, Ysgol Grist.
Planhigyn blodeuol lluosflwydd a dyf yng ngorllewin Ewrop ydy Eurinllys trydwll sy'n enw gwrywaidd. Mae'n perthyn i'r teulu Hypericaceae. Yr enw gwyddonol (Lladin) yw Hypericum perforatum a'r enw Saesneg yw Perforate st john's-wort. Ceir enwau Cymraeg eraill ar y planhigyn hwn gan gynnwys Eurinllys Trydwll, Candoll, Cantwll, Eurinllys Tyllog, Llysiau loan, Tarfwgan, Ysgol Fair, Ysgol Grist.
Třezalka tečkovaná (Hypericum perforatum) je známým představitelem rodu třezalka. Je to vytrvalá bylina se vstřícnými jednoduchými listy a zlatožlutými, pravidelnými květy v bohatých květenstvích. Je rozšířena v Evropě, Asii a severní Africe. V České republice roste zejména na výslunných stanovištích nižších a středních poloh.
Třezalka tečkovaná je významná léčivá rostlina. V současné medicíně je využívána zejména při léčení deprese a úzkosti a také pro její antivirotické účinky. Hlavními účinnými látkami jsou hypericin a hyperforin.
Bylina sv. Jana, čarovník, krevníček, prostřelenec, svatojánská bylina.
Třezalka tečkovaná je statná, vytrvalá, lysá bylina, dorůstající obvykle výšky 20 až 60 cm. Lodyha je přímá nebo vystoupavá, většinou nevětvená, se 2 vystouplými podélnými lištami, jednoletá, v průběhu sezóny poněkud dřevnatějící. U báze stonku bývají lišty někdy nezřetelné. Listy jsou podlouhlé, vejčité nebo kopinaté, přisedlé nebo krátce řapíkaté, 15 až 35 mm dlouhé a 5 až 15 mm široké. Čepel listů je celokrajná, na okraji slabě až silně podvinutá, na ploše tečkovaná siličnými nádržkami a tmavými žlázkami. Proti světlu prosvítají jen hlavní žilky, zatímco drobnější žilky jsou nezřetelné.
Květenství jsou bohatá, poměrně volně uspořádaná. Květy mají průměr 15 až 30 mm. Koruna je zlatožlutá, složená z 5 výrazně nesouměrných, na jedné straně zubatých korunních lístků o délce 8 až 18 mm. Tyčinek je asi 50. Na vrcholu semeníku jsou 3 volné čnělky, asi 2x delší než semeník. Plodem je vejcovitá, přehrádkosečná tobolka obsahující mnoho hnědých až černých, drobných, jen asi 1 mm dlouhých semen.[1][2]
List a lodyha
Řez stonkem
Detail květu
Nedozrálý plod
Třezalka tečkovaná bývá zaměňována zejména s třezalkou skvrnitou, která je rovněž hojným druhem. K jejich bezpečnému rozlišení stačí prohlédnout list proti světlu. U třezalky tečkované jsou v žilnatině dobře patrné pouze hlavní žilky, zatímco postranních je málo, jsou nepříliš zřetelné a nespojují se. U třezalky skvrnité je jasně patrná i postranní žilnatina, která je podstatně hustší a síťovitě pospojovaná. Dalším spolehlivým rozlišovacím znakem je počet lišt na lodyze. Třezalka tečkovaná má 2 nepříliš výrazné podélné lišty, zatímco u třezalky skvrnité jsou 4 lišty. Tento znak je lépe patrný v horní části lodyhy. Další, méně běžný druh třezalka čtyřkřídlá má rovněž 4 lišty, které jsou u tohoto druhu výrazné a silně vystouplé. Žilnatina listů je řídce síťovitá. Všechny ostatní, vesměs vzácnější, vzpřímeně rostoucí druhy třezalek vyskytující se v ČR mají žláznatě zubatý okraj kališních lístků, kdežto výše zmíněné 3 druhy mají kališní lístky celokrajné. Třezalka chlupatá se navíc liší ochlupenou lodyhou i listy.[1] Třezalku tečkovanou lze odlišit od řady jiných druhů též mikroskopicky podle listového okraje, a to i v sušeném nebo drceném stavu.[3]
Rostlina nese 2 typy žlázek s rozdílnou funkcí, obsahem i stavbou. Nejhojněji jsou zastoupeny bezbarvé, průsvitné siličné žlázky, které daly třezalce tečkované její druhové latinské jméno (perforatus = propíchaný, dírkovaný). Proti světlu vypadají jako drobné vpichy, rovnoměrně rozptýlené po celé ploše listu. Jsou přítomny i ve květech a plodech. Žlázky jsou tvořeny schizogenní nádržkou, vzniklou v mezibuněčném prostoru rozestoupením buněk. Žlázka vyplňuje celou tloušťku listové čepele a na povrchu listu je překryta pouze jednobuněčnou vrstvou pokožky. Od listového parenchymu je oddělena vrstvou plochých buněk. Obsah je olejovitý, tvořený zejména esenciálními oleji (silicemi). Ve žlázkách nacházejících se v květech a nezralých plodech je obsažena také medicínsky významná látka hyperforin.
Tmavé žlázky naproti tomu vypadají jako drobné černé tečky a mají zcela odlišnou stavbu. Jsou tvořeny shlukem (uzlinou) větších buněk obklopených ze všech stran dvojitou vrstvou plochých buněk. Obsah je černý a má zrnitou strukturu. Tmavé zbarvení jim dává obsažené červené barvivo hypericin a pseudohypericin. Na listech jsou soustředěny zejména podél listového okraje, několik jich však bývá rozptýleno i na ploše čepele. V květech se nacházejí zejména podél okraje korunních plátků a na vrcholu tyčinek.
Vrstvy plochých buněk obklopující žlázky obou typů jsou napojeny na cévní systém. Na korunních lístcích bývají mimo kulovitých žlázek přítomny i světlé a tmavé trubicovité struktury s obdobným obsahem.[4] [5]
Druh je rozšířen téměř v celé Evropě s výjimkou arktických oblastí. V Asii jeho areál dosahuje po střední Sibiř, Mongolsko, Čínu a severozápadní Indii. Vyskytuje se též v severozápadní Africe (pohoří Atlas), Madeiře a Kanárských ostrovech. Byla zavlečena do mírných a subtropických oblastí téměř celého světa.[1][6][2]
V České republice je třezalka tečkovaná hojně rozšířena zejména v nižších a středních polohách. Ve vyšších horských polohách se vyskytuje vzácněji. Nejčastěji roste na výslunných stanovištích na stráních, mezích a pastvinách, na okrajích lesů, pasekách a podobně, na stanoviště však není moc vybíravá.[1]
Třezalka tečkovaná byla lidskou činností postupně zavlečena do oblastí mírného pásu téměř celého světa. Hojně se rozšířila zejména v Severní a Jižní Americe, Austrálii a Jižní Africe.[7] V mnohých oblastech se intenzivně šíří a celkem ve 20 zemích světa je vedena jako invazní rostlina. V USA a Kanadě je řazena mezi přední plevelné rostliny.
Do Austrálie byla třezalka tečkovaná přivezena v patrně v polovině 19. století, kdy byla pěstována v botanických zahradách v Melbourne a Adelaide. Zplaněle rostoucí byla poprvé nalezena v roce 1880 ve státě Victoria, o 10 let později i v Novém Jižním Walesu. Následně se masově rozšířila zejména v jihovýchodní části kontinentu, kde je celková výměra jejích porostů odhadována na 400000 hektarů. Roste zejména na různých typech pastvin, řídké lesní vegetaci i savanách, podél cest a na narušených místech. V rozpětí 70 let bylo v Austrálii v rámci boje s touto rostlinou postupně vysazeno 12 druhů hmyzu, z nichž polovina se uchytila. V první polovině 20. století sem byly dovezeny z Evropy 2 druhy mandelinek, které třezalku spásají: Chrysolina quadrigemina a Ch. hyperici. Výsledky ovšem nebyly dostatečné a později byl úspěšně introdukován roztoč Aculus hyperici, který patří k hlavním patogenům třezalky ve Středomoří. Ve 40. letech 20. století byly oba druhy mandelinek dovezeny též do USA.[8][9][10][11]
Ve Spojených státech pochází první záznam o výskytu třezalky tečkované z Pensylvánie z roku 1793. Později se masově rozšířila zejména v západních oblastech kontinentu. Jenom v Kalifornii okupovala ve 40. letech 20. století území o rozloze 1 milión hektarů. Nejvíce jsou postiženy pastviny, které byly v minulosti nadměrně vypásány a dominují na nich nepůvodní, jednoleté druhy trav, jako je např. sveřep střešní (Bromus tectorum). Na pastvinách třezalka snižuje kvalitu píce a způsobuje dobytku zdravotní potíže vlivem fotosenzibility.[12] V některých oblastech USA se podařilo třezalkové porosty silně zredukovat. Např. v Idaho dnes zabírají jen asi 3 % rozlohy z roku 1948. V některých oblastech však pastviny po úspěšné biologické redukci třezalky zarostly nějakým jiným nežádoucím druhem, jako je toxický starček přímětník (Senecio jacobaea) nebo chrpa Centaurea maculosa. V Kalifornii pokleslo zamoření třezalkou po 10 letech od aplikace biologické kontroly na 1 % původního stavu. Počáteční úspěch byl tak velký, že mandelince Ch. quadregemina byla ve městě Eureka postavena téměř 2 metry velká bronzová socha.[12]
Na třezalce tečkované se živí řada druhů hmyzu. V České republice jsou to např. některé mandelinky rodu Chrysolina a housenice pilatky Tenthredo amoena. Hmyz živící se třezalkou se musí vypořádat se škodlivým působením hypericinu, koncentrovaného v tmavých žlázkách. Nespecializovaní spásači se zpravidla vyhýbají částem rostliny s větší koncentrací tmavých žlázek, jako je listový okraj. Příkladem mohou být různé kobylky, např. kobylka zelená. Někteří specializovaní spásači třezalky se chrání před slunečním světlem, které iniciuje toxicitu hypericinu. Mezi takové spásače náleží např. můra osenice půvabná (Actinotia polyodon, syn. Cloantha perspicillaris), mandelinky bázlivec vratičový (Galeruca tanaceti) a Chrysolina geminata. Některé druhy hmyzu jsou schopny hypericin odbourávat pomocí enzymů s antioxidačním účinkem (zejména glutathion-S-transferáza). Patří mezi ně zavíječ kukuřičný (Ostrinia nubilalis), píďalka úhorová (Anaitis plagiata) a lišaj Manduca sexta.[9][13] Ve Středomoří třezalku spásá hlavně krascovitý brouk polník třezalkový (Agrilus hyperici) a roztoč Aculus hyperici.[8]
Mandelinka proměnlivá (Chrysolina varians)
Larva Chrysolina varians na třezalce
Mandelinka Chrysolina hyperici
Larva pilatky Tenthredo amoena
Třezalka tečkovaná se převážně rozmnožuje apomikticky, je však schopna i pohlavního rozmožování. Převažují tetraploidní rostliny (2n = 32), příležitostně byly zjištěny i diploidní a hexaploidní typy, což je vysvětlováno jako důsledek fakultativní apomixie. Druh je považován za dávného křížence dvou různých diploidních druhů třezalek. Jako jeden z rodičovských druhů byla identifikována třezalka skvrnitá (konkrétně poddruh H. maculatum subsp. immaculatum), druhým by mohl být asijský druh H. attenuatum, nesoucí znaky přítomné u třezaly tečkované a chybějící u třezalky skvrnité. Areály obou taxonů se překrývají v oblasti Altaje. Při studiu embryologie tetraploidní třezalky tečkované bylo zjištěno, že meióza probíhá pouze asi ve 3 % zárodečných vaků, zatímco ve zbývajících vacích dochází k apomixii. Zárodečná buňka při ní sice vstupuje do procesu meiózy, později však zakrňuje a funkci zygoty přebírá somatická buňka zárodečného vaku s neredukovaným počtem chromozomů, která se dále dělí mitoticky bez redukčního dělení. Při oplození tak nedochází k rekombinaci DNA, proces oplození je však přesto nutný pro pólová jádra zárodečného vaku, z nichž se formuje endosperm. Bez něj embryo postupně zakrní. U rostliny je tak i při apomiktickém způsobu rozmnožování tvorba semen podmíněna opylením. Tento proces se nazývá pseudogamie.[7] Diploidní rostliny se rozmnožují klasickým pohlavním způsobem.[14] Pyl vzniká normálním meiotickým dělením a je tedy haploidní. Vlivem poruch meiózy bývá okolo 30 % (někdy až 70 %) pylových zrn sterilních.[15]
Rostlina se množí také vegetativně úlomky kořenů a růstem z postranních kořenů. Vegetativní množení je stimulováno zejména spásáním, působením ohně nebo odlistěním rostlin. Mladé rostlinky se brzy osamostatní. Třezalka má hluboký kořenový systém a jeho pomocí přečkává případné požáry vegetace. Kromě toho žár ohně stimuluje klíčení dormantních semen v půdní semenné bance.[12]
Květy třezalky tečkované jsou opylovány různým hmyzem sbírajícím pyl. Nektar se v nich nevytváří. Jsou též schopny samoopylení. Jedna rostlina vytvoří asi 15000 až 34000 semen. V jedné tobolce bývá 400 až 500 semen. Semena se šíří větrem, vodou, prostřednictvím zvířat nebo lidskou činností. Tobolky mají lepkavý povrch a přítomnost tohoto lepkavého exudátu na povrchu semen blokuje klíčení, dokud jej vnější vlivy neodstraní. Semena si udržují klíčivost přibližně 6 až 30 let a bývají v půdní semenné bance zastoupena v hojném počtu.[12]
Druh Hypericum perforatum je v rámci rodu Hypericum řazen do sekce Hypericum a stejnojmenné podsekce a série. Série Hypericum obsahuje celkem 12 druhů, z třezalek rostoucích v ČR sem patří též třezalka skvrnitá, třezalka čtyřkřídlá a třezalka ozdobná.[16][17]
Třezalka tečkovaná je silně variabilní taxon, přičemž různorodost morfologických znaků spočívá zejména ve velikosti a tvaru listů a okvětí a také hustotě žláznatých teček. Jednotlivé formy nejsou jednoznačně ohraničené a jsou mezi nimi plynulé přechody. Jsou rozeznávány 4 vnitrodruhové taxony:
V přírodě se třezalka tečkovaná nejčastěji kříží s autotetraploidním taxonem H. maculatum subsp. obtusiusculum ze vzniku tetraploidních nebo řidčeji i hexaploidních kříženců. Tito kříženci bývají dále plodní. Jsou známi též kříženci s dalšími taxony, kteří však vesměs tvoří jen málo klíčivých semen: nominátním poddruhem H. maculatum subsp. maculatum, H. tetrapterum, H. montanum a H. pulchrum.[7] Kříženec s H. maculatum se nazývá Hypericum × desetangsii.[17]
V třezalce tečkované bylo zjištěno více než 150 různých látek, z nichž řada má prokazatelný biologický účinek. Z medicínského hlediska nejvýznamnější obsahové látky náležejí mezi naftodiantrony (hypericin, pseudohypericin), floroglucinoly (hyperforin, adhyperforin) a flavonoidy. Dále jsou obsaženy xanthony, třísloviny, procyanidiny, fenolické sloučeniny, deriváty antrachinonu, esenciální oleje aj.
Účinné látky ze skupiny naftodiantronů jsou v třezalce tečkované zastoupeny hypericinem a strukturně velmi podobným pseudohypericinem. Souhrnně se obě tyto látky označují jako hypericiny. Jsou koncentrovány v tmavých žlázkách, jimž dávají černé zbarvení. V roztoku jsou červené. Tmavé žlázky jsou s různou četností rozptýleny po celé nadzemní části rostliny. Největší množství hypericinů je obsaženo v květech ve stádiu plného květu (asi 5x až 8x více než v listech), a to zejména v tyčinkách a korunních lístcích. S odkvětem pak jejich obsah klesá. Dvouletá rostlina obsahuje asi dvojnásobek množství hypericinů oproti rostlině v prvnímu roce po výsevu. Biosyntéza hypericinu začíná v zelené rostlinné tkáni prostřednictvím polyketidové dráhy a pokračuje v tmavých žlázkách kondenzační reakcí emodinu a emodin anthronu. Výsledný emodin de-anthron je fenolickou oxidací přeměňován na protohypericin (případně protopseudohypericin), který se působením světla přeměňuje na hypericin (resp. pseudohypericin).[18][15]
V surové nati kolísá obsah hypericinů v závislosti na stádiu rostliny v rozmezí od 0,03 do 0,3 %. Hypericiny jsou zodpovědné za fotosenzibilující efekt, mají antivirové účinky a přispívají též k antidepresivnímu účinku.[19]
Hyperforin je v rostlině téměř výhradně koncentrován v průsvitných žlázkách, a to zejména v generativních orgánech.[20] Největší obsah této látky je v nedozrálých plodech, kde je obsažena v množství asi 4,4 % hmotnosti sušiny (spolu s 1,8 % adhyperforinu). Vyskytuje se také v poupatech a květech, naopak v listech a stonku téměř chybí. Je doprovázena adhyperforinem, který se liší pouze jednou ethylovou skupinou namísto methylové, základní struktura je však stejná. Látka je poměrně nestabilní a snadno oxiduje na celou řadu rozkladných produktů. Je rozpustná v organických rozpouštědlech, v lipofilních roztocích je však značně nestabilní, což souvisí s množstvím dvojitých vazeb ve struktuře a jejich snadnou oxidací mj. atomárním kyslíkem vznikajícím působením světla na hypericin. V lihovém výluhu ze sušeného materiálu je rozložena v průběhu několika dní, v případě výluhu z čerstvých rostlin je její životnost i několik měsíců, což je vysvětlováno přítomností stabilizujících složek v čerstvé rostlině. Hyperforin byl dosud zjištěn v rámci celé rostlinné říše výlučně v třezalce tečkované. Jeho obsah ve dvouletých rostlinách je asi o pětinu vyšší než v 1. roce.[15]
Při vyluhování hyperforinu se jako nejlepší rozpouštědlo ukázal ethanol v minimální koncentraci 70 % . Při použití 40 % ethanolu lze vylouhovat jen asi 1 % celkového množství. Vyšší teplota (60 °C) při vyluhování poněkud snižuje jeho výtěžnost. Působení světla nemá vliv na množství vylouhovaného hyperforinu, ovlivňuje však jeho stabilitu. Nejlepší výsledky z hlediska stability roztoku byly získány při vyloučení světla a přístupu kyslíku při extrakci. K sušení je doporučováno vakuové sušení. Vysušený výluh se ukázal jako stabilní forma. V čajovém nálevu ze sušené třezalkové nati nebyl žádný hyperforin detekován.
Biosyntéza hyperforinu je úzce spojena s biosyntézou monoterpenických esenciálních olejů (silic) a probíhá sloučením acylfloroglucinolu se 3 molekulami isopentenyldifosfátu a jedné molekuly geranyldifosfátu.[20] Hyperforin je hlavním nositelem antidepresivního účinku a je zodpovědný za interakce s ostatními léčivy. V extraktech je obsažen v množství od 0 do 6 %.[19]
Flavonové sloučeniny jsou přítomny buď jako volné flavonoidy či biflavonoidy nebo vázané v podobě glykosidů. Jejich celkový obsah v sušině činí asi 2 až 4 %. Jsou přítomny v květech i listech. Z volných jednoduchých flavonoidů převládá kvercetin, kempferol, myricetin, dihydrokvercetin a luteolin. Flavonoidní složka glykosidů (aglykon) je tvořena téměř výhradně kvercetinem. Mezi tyto glykosidy náleží u třezalky rutin, hyperosid, isokvercitrin, kvercitrin a jiné. Z biflavonoidů jsou přítomny zejména biapigeniny a amentoflavon. Tyto látky byly zjištěny výhradně v květech.[15][19]
Bylo zjištěno, že obsah hyperosidu v prvním roce po výsevu představuje jen asi 13 % jeho obsahu ve dvouleté rostlině. Množství a poměr rutinu a kvercitrinu se mění v závislosti na nadmořské výšce. Se stoupající nadm. výškou obsah rutinu stoupá, zatímco obsah kvercetinu klesá.[15] Flavonoidy představují nejrozsáhlejší skupinu sekundárních metabolitů třezalky. Mají antidepresivní účinek, zejména však zlepšují farmaceutické působení jiných obsahových látek, jako jsou např. hypericiny.[19]
Esenciální oleje jsou koncentrovány v průsvitných žlázkách, rozptýlených po celé nadzemní části rostliny. V silici bylo zjištěno celkem 29 různých složek.
Xanthony jsou látky charakteristické pro čeledi třezalkovité a hořcovité. Jsou koncentrovány zejména v kořenech. V kořeni třezalky tečkované jsou zastoupeny zejména norathyriolem, mangiferinem, isomangiferinem a kielkorinem. Norathyriol je přítomen v množství asi 0,0004 %.[4][15]
Třísloviny jsou v třezalce zastoupeny v množství asi od 6 do 15 %. Jsou tvořeny zejména katechinovými a epikatechinovými jednotkami. Jsou přítomny též jednodušší procyanidiny.[15]
Hypericin
Hyperforin
Flavonoidní glukosid hyperosid
Norathyriol ze skupiny xanthonů
Hlavní medicínský význam třezalky spočívá v léčení lehkých a středně těžkých forem deprese. Tento účinek byl potvrzen množstvím kontrolovaných randomizovaných klinických studií (do roku 2009 jich bylo provedeno více než 50) a je z medicínského i farmakologického hlediska nejprozkoumanější.[21] Dále byl také prokázán účinek při léčbě somatoformních poruch a úzkostných stavů. Z jiných oblastí využití ukazují ojedinělé studie pozitivní účinek při léčbě oparu a v kombinaci s ploštičníkem hroznatým (Cimicifuga racemosa) při klimakterických potížích. V rámci provedených klinických studií nebyl prokázán účinek na dětskou hyperaktivitu, sociální fobii, bolesti při polyneuropatii a syndrom pálících úst.[19] Třezalková mast standardizovaná na obsah hyperforinu (1,5 %) má prokázanou účinnost při léčbě atopického ekzému.[22] Preklinické studie ukázaly také jejich potenciálně slibné sedativní, anxiolytické (proti úzkostným stavům), nootropické (zlepšující schopnosti mozku), antischizofrenické (léčba schizofrenie), antikonvulzivní (tlumící křeče např. při epilepsii), antidiabetické a analgetické účinky. Mají též potenciál při léčení alkoholové a nikotinové závislosti. Mohou být také účinné při léčbě celé řady psychických poruch, jako je generalizovaná úzkostná porucha, poruchy spánku, somatoformní poruchy, obsedantně kompulzivní porucha a sezonní afektivní porucha.[23]
Toxikologické studie neprokázaly že by třezalka tečkovaná měla v krátkém a střednědobém horizontu toxické účinky. Vedlejší účinky užívání této rostliny nebo přípravků z ní vyrobených bývají mírné a zahrnují zejména trávicí potíže a únavu. Poškození kůže vlivem fotosenzitivity se při běžných terapeutických dávkách objevuje zřídka.[24] Výjimečně byly popsány vážnější vedlejší účinky, spočívající v kožních, alergických nebo psychiatrických reakcích. Největším rizikem spojeným s užíváním třezalkových preparátů je jejich interakce s jinými léčivy. Z tohoto důvodu je doporučováno o užívání třezalky informovat ošetřujícího lékaře.[19]
Fotosenzitivita a následné riziko poškození kůže slunečním zářením jsou v souvislosti s třezalkou často zmiňovány. Účinnými látkami jsou hypericiny. Fotosenzitivita se jako vedlejší účinek léčby třezalkou objevuje výjimečně, projevuje se slabě a odezní v horizontu několika dní po konci léčebné kúry. Jedinci s bledou pletí bývají citlivější. K vyvolání projevů fototoxicity je zapotřebí dávky obsahující 30x až 50x více hypericinu než je v běžných terapeutických dávkách.[4][24][19]
Výzkum farmakologického působení třezalky ukázal, že floroglucinoly v ní obsažené (hyperforin, adhyperforin) ruší účinek některých léků. Mechanismus tohoto účinku spočívá v aktivaci enzymů, které léčiva v organismu odbourávají, konkrétně cytochromu P450 3A4 a P-glykoproteinu. Výsledkem pak je pokles hladiny daných medikamentů v krvi a související oslabení jejich terapeutického účinku. Mezi léky, které třezalka takto ovlivňuje mimo jiné patří antikoncepční přípravky, léky na ředění krve (warfarin), imunosupresiva (cyklosporin), antidepresiva, chemoterapeutika používaná při léčbě rakoviny (irinotekan), kardiotonika (digoxin), antiastmatika (theofylin) a léky proti AIDS (idinavir).[25][26][19]
Autoři prvních odborných studií účinku třezalky na centrální nervovou soustavu došli k závěru, že hlavní mechanismus antidepresivního účinku této rostliny spočívá v inhibici monoamin-oxidázy, enzymu který se v těle podílí na odbourávání biogenních aminů. V kombinaci se stravou bohatou na tyramin, jako je červené víno nebo sýr, anebo s některými léčivy (sympatomimetika, antidepresiva) je v takovém případě riziko potenciálně škodlivých vedlejších účinků projevujících se zejména prudkým zvýšením krevního tlaku (hypertenzní krize). Tyto závěry ovšem v pozdějších studiích nebyly potvrzeny a bylo zjištěno, že účinek třezalky je komplexnější a postavený na odlišných mechanismech. Obsah flavonoidových aglykonů vyvolávajících tento účinek je v třezalce příliš nízký na to, aby se mohl při běžném dávkování tento účinek projevit. Navíc není v odborné literatuře dosud popsán ani jediný klinický případ takové interakce.[21][27][28][29][24] Přesto s tímto potenciálním účinkem dále operuje např. i oficiální zpráva Evropské komise z roku 2002, týkající se zdravotních rizik potravních doplňků s obsahem třezalky a hypericinu.[30]
Účinek užívání třezalkových preparátů na vývoj plodu není dosud uspokojivě prozkoumán. Obecně se užívání těchto preparátů v době těhotenství a při kojení spíše nedoporučuje. Některé studie ukázaly nižší porodní váhu, zatímco v jiných bylo užívání třezalky v době těhotenství bez viditelného dopadu na vývoj plodu.[19]
Třezalka je ve větším množství toxická pro spásající dobytek kvůli obsahu hypericinu a následné fotosenzibilitě.[10] Mezi charakteristické projevy patří u hospodářských zvířat zejména puchýře a otoky. Nejméně odolní jsou koně, nejvíce kozy. Obecně jsou tmavě zbarvená zvířata lépe chráněna než světlá. Úhyn zvířat je výjimečný, některé průvodní jevy (slepota, otok nebo bolesti tlamy) zabraňují zvířatům v přijímání potravy a vody, což následně může vést ke smrti dehydratací nebo hladověním. Kozy a hovězí dobytek se třezalce spíše vyhýbá a konzumuje ji zejména při nedostatku jiné pastvy.[12]
Sušená nať třezalky tečkované
Třezalka byla využívána jako léčivá rostlina již za časů Starověkého Řecka a také ve středověku. Věřilo se, že je naplněna magickou silou a ochraňuje před zlem a nemocemi. Pedanius Dioscorides, řecký lékař a botanik žijící v prvním století našeho letopočtu, rozlišoval celkem 4 druhy třezalek, mezi nimi i třezalku tečkovanou pod názvem Uperikon. Doporučoval je spolu s medovou vodou na ischias a zevně na spáleniny. V Galénově systému je třezalka popisována jako bylina povahy horké a suché. Paracelsus píše že může být užita jako amulet proti zakletí a přízrakům. Bylina byla hojně využívána v předkřesťanské Anglii a z této doby se k ní dochovala řada legend. Středověký botanik John Gerard uváděl že mast z této byliny je nejdrahocennější prostředek k hojení hlubokých zranění a že lepšího přírodního balzámu pro tyto účely není. Herbalisté ze 16. a 17. století ji uvádějí pod starým latinským názvem Fuga daemonum s tím, že sloužila k odhánění démonů. Niocholas Culpeper, anglický botanik, lékař a astrolog ze 17. století, přiřadil třezalku zvířetníkovému znamení Lva a domu Slunce. Doporučoval ji jako jedinečnou bylinu k léčení ran s tím, že léčí vnitřní zranění a zhmoždění a v podobě masti rozpouští otoky, uvolňuje neprůchodnost a uzavírá okraje rány k sobě. Doporučoval ji také při bodnutí či kousnutí jakýmkoliv jedovatým zvířetem, ischiasu, epilepsii a ochrnutí. Třezalkový olej byl v minulosti používán chirurgy k čištění ran. V Evropě patřil k neoblíbenějším lidovým prostředkům na odřeniny, zranění a pohmožděniny. Brzy po jejím zavlečení do USA ji zařadili do svého výběru léčivých rostlin po bok severoamerickým druhům třezalek i domorodí indiáni, zatímco mezi bílými Američany začala být oceňována až v polovině 19. století. Koncem 19. století již zde byla používána v obdobných indikacích jako v dnešním bylinářství.[31]
Čerstvá nebo sušená kvetoucí nať třezalky tečkované se označuje jako Herba hyperici. Ta se různými způsoby zpracovává na celou řadu přípravků, přičemž způsob zpracování má zásadní vliv na obsah a skladbu účinných látek. Při léčbě depresí jsou nejvyužívanější sušené alkoholové extrakty upravené do podoby tablet nebo kapslí. Alkoholový výluh se získává ze sušené nati a v rámci poměrně komplikovaného zpracování je zahuštěn, vysušen a poté standardizován na obsah účinných látek. Rozpouštědlem je nejčastěji ethanol, řidčeji methanol. Dalšími lékovými formami získávanými ze sušené rostliny jsou tinktury (tekuté alkoholové výluhy), olejové extrakty nebo tablety lisované přímo z jemně drcené rostliny. Výrobce obvykle při výrobě smísí nať planých i pěstovaných rostlin pocházejících z různých zdrojů a různých let. Čerstvá nať je zpracovávána na homeopatické přípravky, vyluhována v oleji nebo je z ní lisována šťáva.[19]
Na trhu je prodávána celá řada třezalkových preparátů: drcená nať sypaná nebo v nálevových sáčcích, prášek z byliny lisovaný do tablet, suchý extrakt v tabletách a kapslích, tinktury, šťáva lisovaná z čerstvých bylin, macerát v oleji a rovněž homeopatické přípravky.[15]
Medicínský význam preparátů z třezalky prudce vzrostl před rokem 2000. V roce 1995 se v USA prodaly přípravky za 20 miliónů dolarů, o 2 roky později to již byl desetinásobek.[23] V roce 1996 němečtí lékaři předepsali celkem 131 miliónů denních dávek léčivých přípravků z třezalky a na německém trhu bylo v nabídce více než 50 různých preparátů. V roce 1999 se v Evropě prodala třezalka tečkovaná za 6 miliard dolarů (200 miliard Kč podle tehdejšího kurzu dolaru). V letech 2007 až 2008 bylo v Evropě prodáno téměř 10 miliónů balení třezalkových přípravků za rok. Největšími trhy jsou Německo, Ruská federace a Polsko. Prodej v těchto 3 zemích představuje téměř 80 % prodeje v celé Evropě.[24][19][15] Prodej preparátů v Německu čtyřnásobně převyšuje prodej antidepresiva fluoxetinu, známého jako Prozak.[32]
Třezalkový olej (Oleum Hyperici) je tradiční medicínská podoba třezalky. Je používán k domácímu léčení spálenin, drobných zranění a různých kožních neduhů, vnitřně pak při potížích s trávením (dyspepsie).[12][33][19] Při přípravě v domácích podmínkách se čerstvé třezalkové květy napěchují do zavařovací sklenice a zalijí olejem. Většinou se doporučuje olej olivový, občas je používán i lněný nebo kvalitní slunečnicový. Sklenice se uzavře a postaví na několik týdnů na slunce. Po vylouhování se olej zcedí. Uchovává se v uzavřené tmavé nádobě. Trvanlivost je minimálně jeden rok.[34][35][36] Ve veterinární péči se používá buď tekuté podobě nebo ve formě masti. Aplikuje se zevně při zánětech vemene, na záněty, ekzémy, dermatózy ap.[37]
Působením slunečního světla při maceraci dochází k rozkladu hypericinu na rozkladné produkty, které dávají výslednému produktu červené zbarvení a jsou na rozdíl od hypericinu rozpustné v oleji. Čerstvý olej obsahuje účinnou látku hyperforin, její obsah však při uskladnění vlivem oxidace rychle klesá.[38]
V minulosti byla většina třezalky sbírána v přírodě, v souvislosti s rostoucím významem v psychoterapii je stále více pěstována. K získání co do obsahových látek stejnoměrné produkce byly vyšlechtěny kultivary.[39] Je jako zemědělská plodina poměrně nová, přesto je již registrováno několik kultivarů zejména v Německu. Šlechtění dále probíhá. Mezi žádané vlastnosti náleží zejména vysoký a vyrovnaný obsah účinných látek, životaschopnost a odolnost vůči antraknóze.[14] Jednou z nejpěstovanějších forem je polský kultivar 'Topas', registrovaný v roce 1982.[15]
V roce 1995 se na třezalkových plantážích ve Švýcarsku objevila antraknóza, houbové onemocnění způsobující odumírání rostlin, které v podstatě kultury zničilo. Původce byl identifikován jako Colletotrichum gloeosporioides. Později byly vyšlechtěny kultivary proti tomuto onemocnění odolnější.[15]
Hlavními producenty jsou Německo, Polsko a Mallorka. V roce 2003 bylo v Německu oseto třezalkou více než 600 hektarů.[4]
Obrázky, zvuky či videa k tématu třezalka tečkovaná ve Wikimedia Commons
Třezalka tečkovaná (Hypericum perforatum) je známým představitelem rodu třezalka. Je to vytrvalá bylina se vstřícnými jednoduchými listy a zlatožlutými, pravidelnými květy v bohatých květenstvích. Je rozšířena v Evropě, Asii a severní Africe. V České republice roste zejména na výslunných stanovištích nižších a středních poloh.
Třezalka tečkovaná je významná léčivá rostlina. V současné medicíně je využívána zejména při léčení deprese a úzkosti a také pro její antivirotické účinky. Hlavními účinnými látkami jsou hypericin a hyperforin.
Prikbladet perikum, Prikbladet perikon eller Johannesurt (Hypericum perforatum) er en 40-60 cm høj urt, der vokser på overdrev, vejkanter og i lysåbne skove. Den dufter kraftigt, når man rører ved den.
Prikbladet perikon er en løvfældende flerårig urt eller halvbusk med en opret, stiv vækst. Bladene er modsatte og helrandede med talrige små, sorte prikker (kirtler). Blomsterne sidder i endestillede kvaste, og de er smørgule og 5-tallige.
Rodnettet er kraftigt og dybtgående.
Højde x bredde og årlig tilvækst: 0,50 x 0,25 m (50 x 5 cm/år).
Planten findes vildtvoksende overalt i Danmark på overdrev, tørre enge, strandoverdrev, vejkanter og i lysåbne skove og krat. Den hører hjemme på tør og mager bund, hvor den klarer sig fint i konkurrencen med græsser og andre kraftige stauder.
Prikbladet perikon er velegnet i en anlagt blomstereng. Den er også værdifuld som biplante på grund af den sene blomstring. Og så kan de uudsprungne knopper bruges til at fremstille kryddersnaps.
Planten bruges i naturmedicin som erstatning for antidepressiv medicin.
Prikbladet perikon (og præparater heraf) har påviseligt indflydelse på omsætningen af lægemidler [1]. Mekanismen er opregulering af to enzymer: cytokrom P450 og CYP3A4, men også CYP2C9, der bevirker en øget nedbrydning af medicinen, hvad der medfører lavere koncentration i kroppen og mindsket, klinisk effekt. Det afgørende i denne forbindelse formodes at være plantens indhold af hyperforin.
Prikbladet perikum, Prikbladet perikon eller Johannesurt (Hypericum perforatum) er en 40-60 cm høj urt, der vokser på overdrev, vejkanter og i lysåbne skove. Den dufter kraftigt, når man rører ved den.
Das Echte Johanniskraut (Hypericum perforatum), auch Echt-Johanniskraut, Gewöhnliches Johanniskraut, Durchlöchertes Johanniskraut, Tüpfel-Johanniskraut oder Tüpfel-Hartheu, meist kurz Johanniskraut oder Johanneskraut, genannt, ist eine Pflanzenart aus der Gattung der Johanniskräuter (Hypericum) innerhalb der Familie der Hypericaceae (früher Hartheugewächse). Es findet Anwendung als Heilpflanze, vor allem als mildes Antidepressivum.
Volkstümlich wird das Echte Johanniskraut (lateinisch hypericum, früher auch ypericon[1] und Hypericon[2]) auch als Herrgottsblut bezeichnet.[3] Der Name bezieht sich auf Johannes den Täufer, da die Pflanze um den Johannistag (24. Juni) herum blüht.[4] Auch die lateinische Bezeichnung Flores sancti Johannis,[5] der englische Name St John’s wort und der spanische Name hierba de San Juan beziehen sich auf Johannes den Täufer.
Das Echte Johanniskraut ist eine ausdauernde krautige Pflanze, die Wuchshöhen von 15 bis 100 Zentimetern erreicht. Sie bildet stark verzweigte Wurzelkriechsprosse und eine spindelförmige, bis zu 50 Zentimeter tief reichende Wurzel. Der aufrechte Stängel ist durchgehend zweikantig und innen markig ausgefüllt (nicht hohl). Dadurch unterscheidet sich das Echte Johanniskraut von anderen Johanniskrautarten. Im oberen Bereich des Stängels ist das Echte Johanniskraut buschig verzweigt.
Die gegenständig angeordneten Laubblätter sind mehr oder weniger sitzend. Die einfache Blattspreite ist bei einer Länge von bis zu 3 Zentimetern oval-eiförmig bis länglich-linealisch. Die Blattspreite ist dicht mit durchscheinenden Öldrüsen besetzt. Der Blattrand ist mit schwarzen Drüsen punktiert. Bei den zahlreichen durchscheinenden Punktierungen der Spreite handelt es sich um Gewebslücken, die durch Spaltung oder Auseinanderweichen von Zellwänden entstanden sind und in denen das helle ätherische Öl konzentriert ist.
Die Blütezeit reicht von Juni bis August. Der meist reichblütige trugdoldige Blütenstand ist aus Dichasien mit (zur Fruchtzeit gut erkennbaren) Schraubeln zusammengesetzt.
Die zwittrigen Blüten sind radiärsymmetrisch und fünfzählig mit doppelter Blütenhülle. Die fünf Kelchblätter sind bis zu 5 Millimeter lang, länger als der Fruchtknoten, (ei)-lanzettlich, fein grannenartig zugespitzt, mit hellen und schwarzen Drüsen. Die fünf goldgelben Kronblätter sind bis 13 Millimeter lang, nur auf einer Seite gezähnt und am Rande schwarz punktiert. Die Kronblätter enthalten in Gewebslücken das blutrote Hypericin, das beim Zerreiben (am besten mehrere Blütenknospen nehmen) auf den Fingern eine Rotfärbung hinterlässt. Die einzelnen Kronblätter sind aufgrund ihrer gedrehten Knospenlage etwas asymmetrisch, sodass die ganze Blüte in offenem Zustand einem „Windrad“ ähnlich sieht. Die 50 bis 60, manchmal bis 100 Staubblätter umgeben in drei Büscheln angeordnet den Fruchtknoten. Aus den drei Staubblattanlagen entstehen durch zentrifugales Dedoublement drei Cluster mit insgesamt bis zu 100 Staubblättern; siehe Sekundäre Polyandrie.[6] Der oberständige, ovale Fruchtknoten ist in drei Fächer unterteilt, die kürzer sind als die Kelchblätter. Statt Nektar ist ein anbohrbares Gewebe von unsicherer ökologischer Bedeutung vorhanden.
Die Frucht besteht aus einer schmal-eiförmigen, bis 10 Millimeter langen, gerieften dreifächrigen Spaltkapsel. Die Samen sind bei einer Länge von etwa 1 Millimetern länglich, gebogen und fein netzförmig.
Die Chromosomenzahl beträgt 2n = 32 oder 48.[7]
Beim Echten Johanniskraut handelt es sich um eine sommergrüne Schaftpflanze (überwinternde Pflanze ohne Rosette) und Hemikryptophyten. Es wurzelt bis 50 Zentimeter tief.[7]
Blütenökologisch handelt es sich um eine homogene „Pollen-Scheibenblumen“. Fremdbestäubung erfolgt durch Pollen suchende Insekten. Besucher sind besonders Bombus-Arten und Bienen- und Schwebfliegen-Arten. Selbstbestäubung ist durch die räumliche Trennung von Griffelästen und Staubbeutelbündeln erschwert, ist aber beim Schließen der Blüten möglich, wenn die schrumpfenden Kronblätter die Blüte wieder einhüllen. Am Abend und beim Abblühen rollen sich die Blütenblätter an den Seiten in der Längsachse ein.
Die kleinen Samen der bei Trockenheit geöffneten Kapselfrüchte werden von Tieren verschleppt (Zoochorie) oder durch den Wind verbreitet (Ballonflieger). Vegetative Vermehrung erfolgt durch Wurzelkriechsprosse.
Die Pflanzenteile sind leicht giftig. Die getrockneten Blüten des Behaarten Johanniskrauts enthalten bis zu 1,4 % des roten Farbstoffes Hypericin („Johannisblut“). Die Hypericin-Aufnahme führt bei nicht pigmentierten (weißen) Weidetieren (Pferde, Schafe, Ziegen etc.) nach der Bestrahlung durch Sonnenlicht zu Hämolyseerscheinungen („Hartheukrankheit“).
Das Echte Johanniskraut ist die in Europa am weitesten verbreitete Art der Gattung Hypericum und in Europa, Westasien und Nordafrika heimisch. In Ostasien, Nord- und Südamerika und in Australien ist es eingebürgert worden. Man findet es in tiefen bis mittleren Höhenlagen. Es wächst verbreitet in Gebüschsäumen, an Waldrändern, Wegen und Böschungen, in Magerwiesen und -rasen, in Ginster- und Heidekrautheiden, in Brachen und Waldverlichtungen oder auf Bahnschotter als Pionierpflanze. Es gedeiht in Gesellschaften der Klassen Trifolio-Geranietea, Epilobietea angustifolii oder auch des Verbands Dauco-Melilotion.[7]
Das Echte Johanniskraut tritt vorwiegend in größeren Gruppen auf, allerdings sind diese selten bestandsbildend. Als ökologische Zeigerwerte nach Ellenberg wird Hypericum perforatum als Halbschattenpflanze für mäßigwarme bis warme Standorte bei gemäßigtem Seeklima angegeben. Die angezeigte Bodenbeschaffenheit ist gleichmäßig trocken bis mäßig feucht und stickstoffarm, niemals jedoch stark sauer.
Die Erstveröffentlichung von Hypericum perforatum erfolgte durch Carl von Linné.
Je nach Autor gibt es mehrere Varietäten oder Unterarten:
Johanniskraut guter Qualität enthält durchschnittlich 0,1–0,15 % Gesamt-Hypericine (Ph. Eur. 5.0, S. 2485), welche vor allem in den Exkretblättern der Blüten und Knospen lokalisiert sind. Diese setzen sich aus durchschnittlich 0,2–0,3 % Hypericin, Pseudohypericin und ähnlichen Substanzen zusammen. Für die Wirksamkeit sind des Weiteren 2–4 % Flavonoide und Bioflavone verantwortlich. Bisher ausschließlich in dieser Art nachgewiesen wurden das antibiotisch wirksame Hyperforin sowie das Adhyperforin in den Blüten (2 %) und Früchten (4 %).
Nachdem der Hypericingehalt bis 1995 zur Bestimmung der Wirksamkeit der Droge Hyperici herba benutzt wurde, geht man inzwischen davon aus, dass die therapeutische Wirksamkeit durch ein Zusammenwirken mehrerer Wirkstoffe und Wirkmechanismen zusammenkommt, da ein Gesamtextrakt eine deutlich stärkere Hemmung der Monoaminoxidase bewirkt als isoliertes Hypericin. Zur Arzneimittelherstellung werden Hypericingehalte von 0,15 % und hohe Flavonoidgehalte gefordert, zudem müssen Grenzwerte für Cadmium (0,5 mg/kg) und Blei (5,0 mg/kg) unterschritten werden.
Ein weiterer medizinisch wirksamer Inhaltsstoff ist mit bis zu 7,2 % Gehalt im ätherischen Öl das Sesquiterpen Spathulenol.[10]
Aufgrund der Verwendung als Heilpflanze wird das Echte Johanniskraut landwirtschaftlich angebaut.[11] Gleichzeitig gilt es im übrigen landwirtschaftlichen Anbau als „Unkraut“ und Weideunkraut.
Für die Produktion verschiedener Präparate auf Johanniskrautbasis werden Kultursorten des Johanniskrauts unter Feldbedingungen angebaut.
Bei der Züchtung geeigneter Sorten spielt die Anfälligkeit gegenüber der Pilzkrankheit Rotwelke eine wesentliche Rolle. Es stehen mehrere Sorten zur Verfügung (Stand: 26. April 2004[12]): Anthos, Hyperixtrakt, Motiv, Uperikon, Hyperimed, Hyperiflor, Vitan, Hyperipharm und Hyperisol.
Die Aussaat erfolgt im Frühjahr oder Herbst, auch eine Pflanzung „vorgezogener Setzlinge“ im Frühjahr ist möglich. Gedüngt wird nur wenig, vor allem hohe Stickstoffgaben senken den Hypericingehalt in der Droge. Unkraut muss per Striegel sowie mit Maschinen- und Handhacke reguliert werden, gegen die Rotwelke darf nach der Ernte ein Fungizid eingesetzt werden.
Die Kultur erfolgt über zwei bis drei Jahre, geerntet wird ein bis zweimal jährlich. Dabei werden die Knospen, Blüten und Zweigspitzen zur Blütezeit geerntet. Für Frischware wird das Kraut von Hand oder mit einer Pflückmaschine geerntet. Zur Trocknung vorgesehenes Gut wird mit Spezialmaschinen oder umgebauten herkömmlichen Erntemaschinen (Mähdrescher, Feldhäcksler) eingebracht. Die Krauterträge schwanken stark und liegen zwischen 4 und 26 t Frischmasse pro Hektar.
Den Pflanzen wird unmittelbar nach der Ernte bei 40–60 °C auf Satz-, Horden- oder Bandtrocknern das Wasser bis auf 10 % Restfeuchte entzogen.
Je nach Umweltbedingungen, zum Beispiel unterschiedlich starker Bestrahlung mit UV-B-Licht, verändert sich der Gehalt bioaktiver Inhaltsstoffe.[13]
Echtes Johanniskraut ist eines der in Europa am häufigsten als Beruhigungsmittel und Antidepressivum eingesetzten Phytopharmaka.[14] Die Wirksamkeit ist besser belegt als bei anderen pflanzlichen Präparaten mit vergleichbarem Anwendungsgebiet, wie etwa Lavendelöl und Passionsblumenextrakt, wenn es auch Kritik an der Methodik und Aussagekraft der Studien gibt. Im Allgemeinen sind weniger Nebenwirkungen zu erwarten als bei synthetischen Standard-Antidepressiva.[15]
Bereits in der Antike wurde Johanniskraut als Heilpflanze verwendet. Neben dem Echten Johanniskraut (Hypericum perforatum) kamen (als „Sant Johans Kraut“ und ähnlich benannt) bis in die Neuzeit auch Blut-Johanniskraut (Hypericum androsaemum) und Quirlblättriges Johanniskraut (Hypericum coris)[16] sowie Arnika zum Einsatz.[17] Heute wird Hypericum perforatum als pflanzliches Arzneimittel zur Behandlung von leichten bis mittelstarken depressiven Verstimmungen oder nervöser Unruhe eingesetzt. Äußerlich werden ölige Zubereitungen angewendet. Die Pflanze wurde im Herbst 2014 von Wissenschaftlern der Universität Würzburg („Studienkreis Entwicklungsgeschichte der Arzneipflanzenkunde“) mit Verweis auf das große medizinische Potenzial zur „Arzneipflanze des Jahres 2015“ gewählt.[18]
Die Deutsche Gesellschaft für Psychiatrie und Psychotherapie, Psychosomatik und Nervenheilkunde (DGPPN) führt gemeinsam mit anderen Organisationen und Fachgesellschaften (BÄK, KBV, AWMF) Johanniskraut in der S3-Leitlinie/Nationale Versorgungsleitlinie Unipolare Depression aus dem Jahr 2015 als Möglichkeit eines ersten Therapieversuchs bei einer leichten bis mittelgradigen depressiven Episode an. Da nicht genau bekannt ist, welche Inhaltsstoffe in welcher Dosierung und über welchen Mechanismus für die antidepressive Wirkung von Johanniskraut verantwortlich sind, empfiehlt die Leitlinie solche Präparate einzusetzen, deren klinische Wirksamkeit in eigenen Studien gezeigt wurde. Der Einsatz von Johanniskraut bei leichter bis mittelgradiger Depression hat in der Leitlinie den Empfehlungsgrad 0 (= „Kann“-Empfehlung: „Berichte von Expertenkreisen oder Expertenmeinung und/oder klinische Erfahrung anerkannter Autoritäten (Evidenzkategorie IV) oder Extrapolation von Evidenzebene IIa, IIb oder III. Diese Einstufung zeigt an, dass direkt anwendbare klinische Studien von guter Qualität nicht vorhanden oder nicht verfügbar waren.“)[19]
Die pharmakologische Wirksamkeit von Johanniskraut in der Therapie der Depression ist allerdings umstritten. Es gibt sowohl klinische Studien, die eine Wirksamkeit feststellten, als auch solche, die keine Überlegenheit gegenüber Placebo zeigen. Eine Cochrane-Review aus dem Jahr 2008 wertete 29 Studien mit zusammen mehr als 5000 Patienten aus, bei denen nach DSM- oder ICD-10-Kriterien eine Depression (major depressive disorder) vorlag. Die Autoren sehen in den Studien Evidenz, welche nahelegt, dass die Wirksamkeit der Johanniskrautextrakte in den Studien gegenüber Placebo überlegen ist und vergleichbar mit synthetischen Antidepressiva bei besserer Verträglichkeit und geringeren Abbruchraten sei. Da die in den Studien festgestellte Wirksamkeit auch von dem Land, aus dem die Studie stamme, und ihrer Präzision abhänge, könne nicht ausgeschlossen werden, dass einige kleinere Studien aus deutschsprachigen Ländern mängelbehaftet seien und zu optimistische Resultate berichteten.[20] Klinische Leitlinien aus Deutschland, Kanada, den USA und Großbritannien sehen die Wirkung von Johanniskraut noch am besten bei milder oder mittelgradiger Depression nachgewiesen.[21]
Eine erneute Metaanalyse aus dem Jahr 2016, die im Vergleich zum 2008 veröffentlichten Cochrane-Review auch einige neuere Studien miteinbezieht, kommt zu einem ähnlichen Fazit wie letztere.[22]
Das Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen ging 2009 davon aus, dass Johanniskraut einen Effekt bei leichten Depressionen hat. Generell gab es jedoch eine deutliche Abhängigkeit des Effektschätzers von der Studienqualität: Je schlechter die Qualität der Studien ist, desto größer stellt sich das Ausmaß der aufgezeigten Effekte dar und umgekehrt. Bei Betrachtung allein derjenigen Studien mit der besten methodischen Qualität zeigt Johanniskraut nur einen sehr geringen Effekt. Weiterhin geht das Institut davon aus, dass Johanniskraut bei schweren Depressionen nicht hilft. Es erwies sich bei schweren Depressionen in keiner Studie als dem Placebo überlegen.[23]
Die jetzigen Studien liefern noch nicht genügend Daten, um unterschiedliche Johanniskraut-Extrakte miteinander vergleichen zu können oder die optimale Dosis zu ermitteln.[24] Bei leichten Depressionen konnte jedoch in einer Studie eine Dosis-Wirkungsbeziehung experimentell nachgewiesen werden.[25]
Als Hauptwirkstoff des Johanniskrauts gilt Hyperforin. Standardisierter Johanniskrautextrakt erhöht durch eine Wiederaufnahmehemmung der Neurotransmitter Serotonin und Noradrenalin deren Konzentration an den Synapsen. Ebenfalls steigt auch die Konzentration von Gamma-Aminobuttersäure (GABA), Dopamin und L-Glutamat an, was in dieser Form kein Antidepressivum vermag. In der Folge vermindert sich die Anzahl der (noradrenergen) β-Rezeptoren, außerdem bewirkt der Extrakt eine Herunterregulation der 5-HT2-Rezeptoren.[26]
Die Wirkung der Johanniskraut-Präparate soll auf die chemisch definierten Substanzen Hyperforin und das früher als wirksamkeitsbestimmender Inhaltsstoff angesehene[27] Hypericin zurückzuführen sein. Diese bewirken eine geringe bis mittelstarke cerebrale Wiederaufnahmehemmung von Serotonin, Noradrenalin und Dopamin; dies sind bekannte Wirkmechanismen synthetischer Antidepressiva. Das Verhältnis der Wiederaufnahmehemmung beträgt in tierexperimentellen Untersuchungen Serotonin:Dopamin:Noradrenalin:GABA:Glutamat = 2:1:5:1:11.[28] Eine MAO-Hemmung wurde immer wieder behauptet, konnte aber nie nachgewiesen werden. Andere Rezeptoren werden nicht beeinflusst.
Eine Studie über die Wirkung der kombinierten Einnahme mit Extrakt aus der Passionsblume (Passiflora incarnata) kam zu dem Ergebnis, dass die Wiederaufnahmehemmung für Serotonin gesteigert wurde. Beträgt die Hemmung bei Echtem Johanniskraut alleine 60 %, so bringt die Kombination mit Passionsblumenextrakt die Wirksamkeit in den Bereich des zum Vergleich herangezogenen Fluvoxamins, bei dem die Hemmung 90 % beträgt. Eine Erhöhung der Dosierung verringert die Wirksamkeit allerdings wieder. Aufgrund der Wechsel- bzw. Nebenwirkungen des im Johanniskraut enthaltenen Hyperforins wäre es wünschenswert, die Dosierung des Johanniskrautextrakts durch die gleichzeitige Einnahme von Passionsblumenextrakt senken zu können. Die Qualität der Studie wird trotz gewisser Unklarheiten als akzeptabel bis gut bewertet.[29]
Auch Kombinationspräparate von Johanniskraut, Passionsblume und Baldrian werden angeboten.[30]
Johanniskraut-Arzneimittel sind im Allgemeinen gut verträglich, unerwünschte Nebenwirkungen sind gering oder treten selten auf.[31] In Einzelfällen wird von manischen Episoden berichtet, die von Johanniskraut induziert wurden.[32] Außerdem kann Johanniskraut geringe Magen-Darm-Beschwerden, Kopfschmerzen, Erregung und Müdigkeit und eine phototoxische Reaktion der Haut (Sonnenbrandneigung) hervorrufen, da Hypericin die Empfindlichkeit gegenüber UV-Licht erhöht (Photosensibilitätsreaktion). In hoher Dosierung wirkt es u. U. stark phototoxisch. Die Phototoxizität wird jedoch erst bei einer Überdosierung um die 20-fache empfohlene Tagesdosis von 900 bis 1500 mg erwartet[33]. Hellhäutige Menschen, die Johanniskraut regelmäßig einnehmen und sich in Solarien oder auf Urlaubsreisen bräunen wollen, sollten ein Absetzen des Johanniskrautpräparates 14 Tage vor der ersten Licht- bzw. Sonneneinstrahlung in Erwägung ziehen. Bei bekannter Lichtempfindlichkeit ist Johanniskraut zu meiden. Selten kann es zu allergischen Hautreaktionen kommen. Auch Rinder und Pferde, die zu viel Johanniskraut fressen, zeigen die genannten Symptome. Bei sehr hohen Dosierungen kann es zu leichten Formen eines Serotonin-Syndroms kommen. Symptome sind unter anderem Schwindel, Grippegefühl, Bewusstseinseintrübung, unwillkürliche Muskelzuckungen und Angstzustände. Die Überdosierungssymptome können dabei leicht mit den depressiven Symptomen verwechselt werden und zu einer weiteren Erhöhung der Dosis verleiten.
Ende der 1990er Jahre wurde festgestellt, dass Johanniskraut zu einem verstärkten Abbau von anderen Wirkstoffen führt. Deshalb wurde das zuvor frei erhältliche Johanniskraut 2003 der Apothekenpflicht unterstellt. Ausgenommen von der Apothekenpflicht sind Zubereitungen, die in einer Tagesdosis bis zu 1 g Drogenäquivalent und bis zu 1 mg Hyperforin enthalten, Tee und zur äußeren Anwendung bestimmter Frischpflanzensaft oder ölige Zubereitungen (Rotöl). Aufgrund der Wechselwirkungen wurde Johanniskraut in der Republik Irland schon vor einigen Jahren der Verschreibungspflicht unterworfen. Johanniskrautpräparate mit der Indikation „mittelschwere Depression“ unterliegen seit dem 1. April 2009 auch in Deutschland der Verschreibungspflicht.
Johanniskraut induziert die Abbauenzyme Cytochrom P450 3A4 und Cytochrom P450 1A2[34] in der Leber. Die Abbaurate einer Vielzahl von Wirkstoffen steigt somit an, und sie können ihre Wirkung verlieren.[35] Cytochrom P450, Subtyp 3A4 verstoffwechselt u. a. Hormone. So kann Johanniskraut die Wirkung der Anti-Baby-Pille und anderer hormoneller Verhütungsmittel beeinträchtigen.[36] Es bestehen auch Wechselwirkungen mit bestimmten AIDS-Medikamenten (HIV-Proteaseinhibitoren), Antibiotika wie Clarithromycin und einigen Antidepressiva. Die HIV-Proteasehemmer und das Antibiotikum können ihre Wirkung ganz oder teilweise verlieren, was bei den zugrunde liegenden ernsten Erkrankungen schwerwiegende Folgen haben kann. Auch Immunsuppressiva, die zum Beispiel nach Transplantationen gegen die Abstoßungsreaktion des Körpers gegeben werden, werden abgeschwächt. Es sind Todesfälle bei Johanniskrauteinnahme mit gleichzeitiger Immunsuppression beschrieben worden. Johanniskraut senkte in einer schwedischen Studie bei einer Gabe von 600 mg pro Tag mit einem (vergleichsweise hohen) Hyperforin-Gehalt von 4 % nach 14 Tagen die Plasmahöchstkonzentration, die Area under the curve und die Halbwertszeit von Finasterid um etwa 50 %.[37] Betroffen (mit Abschwächung der Wirkung oder Wirkungsaufhebung) sind weiterhin die trizyklischen Antidepressiva Amitriptylin sowie Nortriptylin, Herzglykoside, Antikoagulantien (Phenprocoumon), Methadon, Buprenorphin, Antiepileptika (z. B. Carbamazepin, Valproinsäure), Benzodiazepine (z. B. Diazepam, Alprazolam, Lorazepam) und benzodiazepinähnliche Substanzen (z. B. Zolpidem und Zopiclon) sowie etliche andere Wirkstoffgruppen.[38]
Mit Serotonin-Wiederaufnahmehemmern wie Fluoxetin, Paroxetin, Citalopram etc. besteht die Möglichkeit einer Verstärkung serotoninerg bedingter Nebenwirkungen (Übelkeit, Durchfall, Blutdruckschwankungen, Erregung) bis hin zur Auslösung des lebensgefährlichen Serotonin-Syndroms (starke Blutdruckschwankungen, Fieber, Bewusstseinseintrübung, Verwirrtheit, Krämpfe).[39] Andererseits können einige der Serotonin-Wiederaufnahmehemmer durch die Beschleunigung ihres Abbaus auch in ihrer Wirkung abgeschwächt werden. Bei Einnahme solcher Kombinationen ist die Wirkung schlecht vorhersehbar.
Beim Einsatz in Schwangerschaft und Stillzeit ist Vorsicht geboten.[40] Johanniskraut wurde in der Volksmedizin als Abtreibungsmittel genutzt.[41]
Volksmedizinisch wird Johanniskraut als Tee und Tinktur auch bei Menstruationsbeschwerden und pubertätsbedingten Verstimmungen verwendet.
Das Johanniskrautöl („Rotöl, Johannisöl“, früher[42] auch Sant Johans öl; Oleum Hyperici) wird als Einreibemittel bei Hexenschuss, Gicht, Rheuma, zur Schmerzlinderung nach Verrenkungen und Verstauchungen, zur Wundheilung (Johanniskraut wirkt entzündungshemmend), bei Blutergüssen und Gürtelrose verwendet, kann aber auch innerlich angewandt werden. Auch sollen Sonnenbrand und Verbrennungen gelindert werden. Das Johanniskrautöl gilt als nicht reizendes, „kaltes Öl“.[43] Man gewinnt es, indem man Johanniskrautblüten zwei Monate lang in kaltgepresstes Oliven- oder Sonnenblumenöl einlegt, gelegentlich kräftig schüttelt und in der Sonne stehen lässt. Diesen Vorgang nennt man Mazeration.
Mit einem Ansatzschnaps aus Blüten und Kraut werden Einschlafstörungen und innere Unruhe behandelt.
Johanniskraut-Zubereitungen sind auch vereinzelt in Nahrungsergänzungsmitteln zu finden: dort als Johanniskrautöl („Rotöl“), dem allerdings die innerlichen arzneilichen Wirkungen nicht zugeschrieben werden dürfen.
Wiener Dioskurides 6. Jahrhundert
Pseudo-Dioskurides de herbis femininis Manuskript 14. Jh.
Pavia MS Aldini 211, 14. Jahrhundert
Gart der Gesundheit 1485
Hortus sanitatis 1491
Otto Brunfels 1537
Leonhart Fuchs 1543
Hieronymus Bock 1546
Mattioli / Handsch / Camerarius 1586
Das Echte Johanniskraut (Hypericum perforatum), auch Echt-Johanniskraut, Gewöhnliches Johanniskraut, Durchlöchertes Johanniskraut, Tüpfel-Johanniskraut oder Tüpfel-Hartheu, meist kurz Johanniskraut oder Johanneskraut, genannt, ist eine Pflanzenart aus der Gattung der Johanniskräuter (Hypericum) innerhalb der Familie der Hypericaceae (früher Hartheugewächse). Es findet Anwendung als Heilpflanze, vor allem als mildes Antidepressivum.
Dónderkroed, Sint-Janskruid (Hypericum perforatum) Familie van Hertshooi. De plant ies 20-80 cm hoag. Opvallend zint de twiè euverlangse lieste op de sjtengel en de doorziechtige puntsjes (oliekliere) in de blaar. De bleuj vingk plaats mèt gael blome rónd 't fiès van Sint-Jan op 24 juni tot-sept. 't Kroed sjteit bekènd es heilend tege depressies, meh dao zin aanwiezinge dat bie geliektiedig gebruuk van ander geneesmieddele de hypericine oet diet Dönderkroed de wèrking zou versjtuère! Ónderdeil van de kroedwösj.
'S e Eala bhuidhe, lus-Chaluim-Chille, Achlaisean Chaluim Chille, allas Chaluim Chille (hypericum perforatum) lus a tha air cleachdadh ann an leigheas tràidiseanta an aghaidh an dubh-leannachd.
Is e lus Clann MhicFhionghain e.
'S e Eala bhuidhe, lus-Chaluim-Chille, Achlaisean Chaluim Chille, allas Chaluim Chille (hypericum perforatum) lus a tha air cleachdadh ann an leigheas tràidiseanta an aghaidh an dubh-leannachd.
Is e lus Clann MhicFhionghain e.
Hypericum perforatum (poznat i kao kantarion ili kantarija, žuta kantarija, gospin cvijet, bogorodična trava i gorac) jest cvjetnica iz porodice Clusiaceae / Hypericaceae.
Uobičajeno ime "kantarion" se može odnositi na bilo koju vrstu roda Hypericum. Zato se Hypericum perforatum ponekad naziva "obični kantarion" ili "perforatni kantarion", kako bi se razlikovao od ostalih. To je ljekovita biljka sa antidepresivimnim aktivnostima i potentnim antiupalnim svojstvima, kao inhibitor arahidonat 5-lipoksigenaze i inhibitor COX-1.[1][2][3]
Hypericum perforatum je porijeklom iz Evrope i Azije, ali se proširio širom svijeta kao invazivna vrsta, uključujući i područja SAD, Kanade, Indije, Kine.
Naziv roda Hypericum potiče od grčkih riječi hiper = gore + eikon = na slici, u odnosu na tradicijsku upotrebu biljke za rastjerivanje zala, vješanjem biljke preko vjerske ikone u kući za vrijeme svetog Jovandana (St John's Day). Peforatni kantarion je zeljasta višegodišnja biljka sa velikim, puzajućim rizomom. Stabljika je uspravna, razgranata u gornjem dijelu, a može narasti do visoke oko 1 m. Ona ima nasuprotne, sjedeće, uske, duguljaste listove dužine oko 1–2 cm. Listovi su žuto-zeleni, s upadljivim prozirnim tačkicama, dajući im 'perforirani' izgled, po kojem je biljka dobila latinsko ime.
Cvijetovi su prečnika do 2,5 cm; imaju pet jarko žutih latica, s upadljivim crnim tačkama. Pojavljuju se u širokim cimama na krajevima gornjih grana, između kasnog proljeća, početkom i sredinom ljeta . Čašični listići su istaknuti, sa crnim žljezdanim tačkicama. Cvjetovi imaju mnogo prašnika, koji su ujedinjeni u bazi u tri snopa. Polenova zrna su elipsoidna. Kada se slome pupoljci (ne i sam cvijet) ili mahuna, proizvodi se crvenkasto / ljubičasta tečnost. Kantarion se razmnožava i vegetativno i spolno.
Hipericin, pseudohipericin i hiperhorin mogu biti kvantificirani u plazmi kao potvrda korištenja kantariona i za procijenu uzete doze. Ova tri aktivna supstituenta kod ljudi imaju poluvrijeme eliminacije iz plazmeu rasponu od 15-60 sati. Nijedan od njih tri nije otkriven u uzorcima urina.
Biljka sadrži sljedeće sastojke:
Među brojnim biološki aktivnim sastojcima, smatra se da su posebno djelotvorni mafthodiantronski hipericin i pseudohipericin, uz floroglucinolni derivat hiperhorin. Kantarion također sadrži aktivna eterska ulja sastavljena uglavnom od seskviterpena.
Kantarion, slično kao i druge biljke, sadrži čitav niz različitih hemijskih sastojaka koji mogu biti od značaja za terapeutske efekte. Hiperhorin i adhiperforin su dva floroglucinolna sastojaka kantariona, koji su antagonisti TRPC6 receptora. Shodno tome, oni izazivaju nekonkurentno ponovno preuzimanje inhibicije monoamina (konkretno, dopamina, norepinefrina i serotonina), GABA (glutamat) kada aktiviraju ovaj ionski kanal. U ljudi, aktivni sastojak hiperhorin je također inhibitor PTGS1, arahidonat 5-lipoksigenaze, SLCO1B1 i induktor a cMOAT. Hiperhorin je također protuupalni spoj sa anti-angiogenim, antibiotskim i neurotrofnim svojstvima. Hiperhorin također ima antagonistički učinak na NMDA receptore, koji su tip glutamatnih receptora. Osim toga, kantarion je poznat ragulator obaranja [[adrenergin| β1 adrenergina i regulira postsinapsne [[5-HT1A]] i [[5-HT2A receptore, od kojih su oba vrste serotoninskih receptora . Njegovi drugi spojevi mogu također imati ulogu u antidepresivnim efektima kantariona, kao što su: oligomerni procijanidini, flavonoidi (kvercetin), hipericin i pseudohipericin.
Hypericum perforatum uspijeva u područjima sa dominantnim padavinama i tokom ljeta ili tokom zime. Međutim, rasprostranjenje mu je ograničeno preniskom temperaturom za klijavost ili opstanak sadnica. Uspijeva na visinama većim od 1500 m, sa padavinama manjim od 500 mm, a srednjom dnevnom januarskom temperaturom (u južnoj hemisferi) većom od 240 C, što se smatra ograničavajućim pragovima. Ovisno o ekološkim i klimatskim uvjetima i starosti rozeta, kantarion će izmijeniti oblik rasta i prilagodbe za promociju opstanka. Kišna ljeta posebno usporavaju vegetativni rast biljaka, nakon čega dolazi do opadanja lišča (defolijacije), inposebno usljed najezde insekata ili ispašom. Sjeme može trajati decenijama u prirodnoj banci sjemena tla.
Iako se Hypericum perforatum uzgaja komercijalno u nekim regijama jugoistočne Evrope, navedi se i kao štetni korov u više od dvadeset zemalja. Unesena je vrsta u Južnoj i Sjevernoj Americi, Indiji, Novom Zelandu, Australiji i Južnoj Africi. Na pašnjacima, kantarion djeluje i kao toksični i invazivni korov. Zamjenjuje prirodne biljne zajednice i stočnu hranu i dominira u toj vegetaciji. Tako postaje invazivna vrsta u prirodnim staništima i ekosistemima. Stočna ispaša može izazvati fotosenzibilizaciju, depresiju centralnog nervnog sistema, spontani pobačaj, a može dovesti i do smrti. Efektivni herbicidi za kontrolu vrsta roda Hypericum uključuju 2,4-D, pikloram i glifosat. U zapadnoj Sjevernoj Americi, tri insekta: Chrysolina quadrigemina, Chrysolina hyperici i Agrilus hyperici su uvedena kao biokontrolni agensi.
Cijela biljka
Klijanci
Plod
Cvjet
Studije su potvrdile efikasnost kantariona za tretman depresije kod ljudi. Jedna meta-analiza u 2015. je našla da ima bolju efikasnost na placeboa u liječenju depresije; efikasan je kao standardni farmaceutski antidepresiv, a ima manje neželjenih efekata od drugih antidepresiva. Autori su zaključili da je teško odrediti sistemsku poziciju kantariona u liječenju depresije zbog ograničenja u dostupnim bazama podataka, uključujući i velike varijacije u efikasnosti u ispitivanjima koja su obavljena u njemačkom govornom području u odnosu na druge zemlje. Predloženo da je mehanizam djelovanja gospine trave ide preko inhibicije ponovnog preuzimanja pojedinih neurotransmitera. U 2008. , u Cochraneovom pregledu 29 kliničkih ispitivanja je zaključeno da je superioran u odnosu na placebo u bolesnika s glavnomdepresijom, efikasan kao standardni antidepresiv, ali sa manje neželjenih efekata. Prema podacima Nacionalnog centra za komplementarno i integrativno zdravlje (NCCIH) Nacionalnog instituta za zdravlje, "može pomoći u nekim vrstama depresije, iako dokazi nisu definitivni" ; može ograničiti efikasnost recepture lijekova, a psihoze se mogu javiti kao rijetka nuspojava. NCCIH napominje da kombiniranje kantariona sa određenim standardnim antidepresivima može dovesti do "porasta serotonina potencijalno opasnog po život", jer je mozak meta hemijskih antidepresiva. Ako se unese u velikim količinama, kod konja, ovaca i goveda, biljka može biti otrovna. U Nemačkoj, ponekad je propisivan za liječenje blage do umjerene depresije, posebno kod djece i adolescenata.
Kantarion se općenito dobro podnosi, uz negativan efekat sličan placebu. Neželjeni efekti obično uključuju gastrointestinalne simptome (mučnina, bol u trbuhu, gubitak apetita i dijareja), vrtoglavicu, zbunjenost, umor, sedaciju, [[usta|suha usta, nemir i glavobolju. Sistemi organa u vezi sa neželjenim reakcija na kantarion i fluoksetin (SSRI) imaju analognu učestalost profila; većins tih reakcija uključuje centralni nervni sistem. Kantarion također smanjuje razine estrogena, kao što je estradiol, ubrzava metabolizam, a ne treba da ga uzimaju žene istovremano sa hormonskim pilulama jer upregulira CYP3A4 citohromom P450 sistem u jetra|jetri]]. Iako rijetko, kantarion može izazvati fotosenzitivnost. To može dovesti do vizualne osjetljivost na svjetlo i na opekotine u situacijama koje ne dolaze u normalnim okolnostima.
Kantarion je povezan sa otežavanjem psihoza kod osoba koje imaju šizofreniju.
Potrošnja kantarion nije preporučljiva za one s bipolarnim poremećajem (BP). Postoji zabrinutost da takve osobe s bipolarnom depresijom uzimanjem gospine trave mogu biti pod većim rizikom za manije. Kantarion je interakcija s više lijekova, kao što su SSRI antidepresivi, varfarin i kontrolor rađanja. Kombinirajući sladovina i SSRI antidepresivi i St John-a moglo dovesti do povećane razine serotonina, kada izaziva serotoninski sindrom. Kombinacija estrogena koji sadrže oralne kontraceptive s kantarion može dovesti do smanjenja efikasnosti kontraceptivnih supstanci i na kraju neplanirane trudnoće. Poznato je i da kantarion smanjuje efikasnost lijekova za HIV i povišen holesterol , kao i transplantacijskih lijekova.Valja napomenuti, međutim, da tradicijski SSRI antidepresivi kao što je fluvoksamin imaju slične kontraindikacije.
Dokazano je da kantarion uzrokuje više interakcija putem indukcije enzima citohrom P450, CYP3A4 i CYP1A2 (samo žene). Ovaj lijek za metaboličku indukciju enzima rezultatira u povećanom metabolizmu nekih lijekova, što dovodi do smanjenja koncentracije u plazmi i potencijalnih kliničkih učinaka. Smatra se da su za to, kao glavni sastojci, odgovorni hiperforin i amentoflavon. Za kantarion je također dokazano da uzrokuje interakcije putem indukcije P-glikoproteinskog efluksnog transportera. Povećana razina P-glikoproteina rezultira smanjenom apsorpcijom i većim razmakom uzimanja određenih lijekova, što dovodi do niže koncentracije u plazmi i moguće kliničke efikasnosti
Klasa Lijek Antiretroviralne supstance Nenukleozidni inhibitori reverznih transkriptaza, inhibitrori proteaza Benzodiazepini Alprazolam, Midazolam Hormonska kontracepcija Kombinirani oralni kontraceptivi Imunosupresanti Inhibitori kalcineurina, Ciklosporini, Takrolimus Antiarithmici Amiodaron, Flecainid, Meksiletin Beta-blokatori Metoprolol, Karvedilol Blokatori kalcijevog kanala Verapamil, Diltiazem, Amlodipin Statini (Lijekovi koji reduciraju holesterol) Lovastatin, Simvastatin, Atorvastatin Ostali Digoksin, Metadon, Omeprazol, Fenobarbital, Teofillin, Warfarin, Levodopa, Buprenorfin, IrinotekanU kombinaciji s drugim lijekovima koji mogu podići razinu 5-HT (serotonin) u centralnom nervnom sistemu (CNS), kantarion može doprinijeti razvoju serotoninskog sindroma, nuspojave koja je potencijalno opasna po održavanje lijeka. Lijekovi koji sa kantarionom mogu doprinijeti razvoju serotoninsko sindroma
Lijekovi (po klasama) koji stupaju u interakcije sa kantarionom
Klasa Lijek Antidepresanti MAOI , TCA , SSRI, SNRI , Mirtazapin Opioidi Tramadol, Petidin (meperidin), Levorfanol CNS stimulanti Fentermin, Diethlpropion, Amphetamini, Sibutramin, Kokain 5-HT1agonisti Triptani Psihodelični lijekovi Metilenedioksimethamfetamin (MDMA), LSD, Dimetiltriptamin (DMT), MDA, 6-APB Ostali Selegilin, Ttriptofan, Buspiron , Litij, Linezolid, 5-HTP, DekstrometorfanU velikim dozama, kantarion je otrovan za ispašu stoke (goveda, ovce, koze, konji). Znaci trovanja su opći nemir i iritaciju kože. Nemir se često iskazuje kao valjalje po tlu, mahanje, uvrtanje i trljanje glavom i povremena slabost zadnjih udova sa klecanjem, , zadihan, zbunjenost i depresija. Manija i hiperaktivnost također se mogu pojaviti, uključujući i vrtnje u krug, do iscrpljenosti. Životinje obično traže hlad i smanjuju apetit. Navedena je i preosjetljivost na vodu je, iako neke životinje mogu tražiti vodu za olakšanje, a mogu se javiti i konvulzije nakon udarca u glavu.
Teška iritaciju kože je fizički vidljiva, uz crvenilo nepigmentna i nezaštićena područja. Ovo naknadno dovodi do svrbeža i trljanja, zatim dalje upale, sa eksudacijom i formiranjem krasta. Oštećenja i upale koje se javljaju liče na simptome slinavke i šapa. Kod ovaca nisu uočeni otok licea, dermatitis i otpadanje vune zbog trljanja. Laktacijia životinja može prestati ili se smanjili proizvodnju mlijeka; bremenite životinje mogu pobaciti plod. Često su vidljiva oštećenja vimena. Konji mogu iispoljavati znakove anoreksije, depresije (sa komatoznim stanjem), proširenje zjenica i oticanje konjunktiva.
Među ranim znacima trovanja kantarionom su ubrzano disanje i otkucaji srca nenormalan porast temperature tijela. Pogođene životinje će izgubiti težinu ili ne dobijaju na težini; mlade životinje su više pogođene nego starije . U teškim slučajevima može doći do smrti, kao direktna posljedica gladi ili zbog sekundarnih bolesti ili septihemijskih oštećenja. Neke pogođene životinje se mogu slučajno utopiti. Zabilježene su i slabe mogućnost sisanja janjadi (pigmentiranih i nepigmentnih), što ukazuje na smanjenu proizvodnju mlijeka ili prijenos otrova u mlijeku.
Većina kliničkih znakova u životinja izaziva fotosenzitivnost. Biljke mogu izazvati ili primarnu ili sekundarnu fotosenzitivnost:
Araya i Ford (1981) su istražili promjene u funkciji jetre i zaključili da nema dokaza da Hypericum ima transakcije koje su povezane sa učinkom na izlučivanje kapacitet jetre ili je bilo koja smetnja bila minimalna i privremena. Međutim, u krvnoj plazmi su pronađeni dokazi oštećenja jetre, na visokim i dugim razinama doziranja.
Fotosenzitivnost izaziva upalu kože, čiji mehanizam uključuje pigmentne ili fotodinamske spojeve, koji kada se aktiviraju određene valne dužine svjetlosti dovode do oksidacijske reakcije in vivo. To dovodi do oštrćenja tkiva, posebno uočljivih na i oko dijelova kože koji su izloženi svjetlu. Lagano pokrivena ili slabo pigmentirana područja su najupadljivija. Sklanjanje životinje sa intenzivne sunčeve svjetlosti ublažava simptome trovanja.
Kantarion je proučavan u vezi sa efikasnošću u liječenju nekih somatoformniijh poremećaja. Rezultati početne studije su mješoviti i dalje neuvjerljivi; neka istraživanja nisu našla nikakvu učinkovitost, dok su druga pronašla blago ispoljanje simptoma. Zato su potrebna dalja istraživanja, osobito zbog prikazanog bogatstva biološki aktivnim tvarima.
Glavni sastavni hemijski spoj, hiperhorin, može biti koristan za liječenje alkoholizma, iako nije proučavanoi doziranje, sigurnost i efikasnost. Hiperhorin je također ispoljio antibakterijska svojstva protiv gram-pozitivnih bakterija, iako doziranje, sigurnost i efikasnost takođen nisu ispitivani. Ovaj biljni lijek je također testiran na lipofilne ekstrakte iz kao tematska lijek za rane, ogrebotine, opekotine i bol u mišićima. Pozitivni efekti, koji su uočeni , uglavnom se pripisuju hiperhorinu zbog njegovih eventualnih antibakterijskih i antiupalnih efekata. Zato bi hiperhorin mogao biti upotrebljiv u liječenju inficiranih rana i upalnih bolesti kože. U odgovoru na uključivanje hiperhorina u novo ulje za kupanje, studija za procjenu potencijala iritacije kože je pokazala dobru toleranciju kože za kantarion. Hipericin i pseudohipericin su se pokazali antivirusnu i antibakterijsku aktivnost. Smatra se da se ove molekule vežu nespecifično na virusne i mobilne membrane i mogu dovesti do fotografske oksidacije i uništenja patogena.
Hypericum perforatum (poznat i kao kantarion ili kantarija, žuta kantarija, gospin cvijet, bogorodična trava i gorac) jest cvjetnica iz porodice Clusiaceae / Hypericaceae.
Uobičajeno ime "kantarion" se može odnositi na bilo koju vrstu roda Hypericum. Zato se Hypericum perforatum ponekad naziva "obični kantarion" ili "perforatni kantarion", kako bi se razlikovao od ostalih. To je ljekovita biljka sa antidepresivimnim aktivnostima i potentnim antiupalnim svojstvima, kao inhibitor arahidonat 5-lipoksigenaze i inhibitor COX-1.
Krziżewé drzéwkò abò bòżé drzéwkò (Hypericum perforatum) to je zelé, chtërnégò Kaszëbi ùżiwają do léczeniô schòrzałi wątrobë.
Krziżewé drzéwkò abò bòżé drzéwkò (Hypericum perforatum) to je zelé, chtërnégò Kaszëbi ùżiwają do léczeniô schòrzałi wątrobë.
Li meytrô ou yebe del Sint-Djhan (eto: båbe di sint Djhan, tchesse-diåle, djaenete), c' est ene fleur des tchamps ki florit d' ene bele djaene fleur ås cénk foyes.
No d' l' indje e sincieus latén : Hypericum perforatum
Les foyes, riloukêyes al loumire, shonnèt trawêyes di meye trôs.[1]
C' est ene rilomêye yebe ås maladeyes.
C' est eto l' cåze di fototinrûlijhaedje ås bedots.
Li meytrô ou yebe del Sint-Djhan (eto: båbe di sint Djhan, tchesse-diåle, djaenete), c' est ene fleur des tchamps ki florit d' ene bele djaene fleur ås cénk foyes.
No d' l' indje e sincieus latén : Hypericum perforatum
Tink derom dat de Wikipedy gjin medyske konsultaasje jout!
It sint-janskrûd (Hypericum perforatum) is in plant út de Sint-Janskrûdfamylje (Hypericaceae). De fêste plant wie hiem yn Europa en hat him dêrút wei fierder ferspraat. It krûd bloeit om de nammedei fan Sint-Johannes op 24 juny hinne. De soart wurdt fanâlds as genêskrêftich krûd brûkt en is as plantaardich antydepressivum te krijen.
Sint-janskrûd is rûnom te finen yn ‘e berms lâns de diken en it spoar. De plant wurdt 20-85 sm heech en hat in rûne stâle mei oant twa smelle listen. De keale, elliptyske oant aairûne geefrânige, 1,5-3 sm lange blêden hawwe in soad trochsichtige punten en in stompe blêdfoet. Dy trochsichtige puntsjes binne folle mei etearyske oalje. It Sint-Janskrûd bloeit fan juny oant septimber mei giele blommen. De kroanblêden binne 1-1,6 sm lang. De tsjelkblêden binne lansetfoarmich, spits en geefrânich. De kroanblêden hawwe mar in pear swarte punten. De blommen teare iepen as in tichtteard doaske dat jo oan ien klep iepenlûke. Yn in reagebol fan blomstêfkes is de stamper suver ferstoppe. De giele blommen foarmje in strûs en bloeie likernôch trije dagen. Yn parken en tunen wurdt in ferskaat oan kweekte farianten fan de Sint-Janskrûdfamylje brûkt as boaiembedekker. Dêr binne guon ûnder mei blommen fan wol 7 oant 8 sm.
Yn it natoergebiet It Houtwiel boppe Feanwâlden groeit in hiel bysûnder famyljelid fan de Sint-Janskrûden, it Sompe-sint-Janskrûd. [1]
It sint-janskrûd (Hypericum perforatum) is in plant út de Sint-Janskrûdfamylje (Hypericaceae). De fêste plant wie hiem yn Europa en hat him dêrút wei fierder ferspraat. It krûd bloeit om de nammedei fan Sint-Johannes op 24 juny hinne. De soart wurdt fanâlds as genêskrêftich krûd brûkt en is as plantaardich antydepressivum te krijen.
Sint-janskrûd is rûnom te finen yn ‘e berms lâns de diken en it spoar. De plant wurdt 20-85 sm heech en hat in rûne stâle mei oant twa smelle listen. De keale, elliptyske oant aairûne geefrânige, 1,5-3 sm lange blêden hawwe in soad trochsichtige punten en in stompe blêdfoet. Dy trochsichtige puntsjes binne folle mei etearyske oalje. It Sint-Janskrûd bloeit fan juny oant septimber mei giele blommen. De kroanblêden binne 1-1,6 sm lang. De tsjelkblêden binne lansetfoarmich, spits en geefrânich. De kroanblêden hawwe mar in pear swarte punten. De blommen teare iepen as in tichtteard doaske dat jo oan ien klep iepenlûke. Yn in reagebol fan blomstêfkes is de stamper suver ferstoppe. De giele blommen foarmje in strûs en bloeie likernôch trije dagen. Yn parken en tunen wurdt in ferskaat oan kweekte farianten fan de Sint-Janskrûdfamylje brûkt as boaiembedekker. Dêr binne guon ûnder mei blommen fan wol 7 oant 8 sm.
Švėnta Juonė žuolie, kėtap da Švėntū Juoniū žuolie, Marėjės žuolie, juonžuolė, juonažuolė (lot.Hypericum perforatum) ī tuokis žuolīns, dėdlis liekvarstos.
Švėnta Juonė žuolie daugiametis augals īr, ožaug ons lėg metra aukštoma. Stombris statmens būn, vėršou šakuots; lapā prīšėnē, paėlgi, lėgēs kraštās. Švėnta Juonė žuolės žėidā būn geltuoni, aug krūvuo šloutelies. Žīdia ciela vasara.
Tasā žuolīns aug pėivūs, sausuos retuos medies, kalnū šlātūs, pagriuoviūs. Anam patink sausas ė saulietas vėitas.
Švėnta Juonė žuolie ī liekvarstos nug vėrškėnėma lėgū, alsavėma sonkomu, mažėn kraugīsliu pralaidoma, tink nug ėnkstu oždegėma, akmenū, mažėn nerimavėma. Tepuogė tink žāzduom, suopontē bornā skalautė.
Το Υπερικόν το διάτρητον (Hypericum perforatum) ή κοινώς το βάλσαμο, είναι ανθοφόρο φυτό του γένους Υπερικόν (Hypericum), της οικογένειας Υπερικίδες (Hypericaceae).
Στην Αρχαία Ελλάδα, ήταν γνωστό ως «υπερικόν», ενώ στη νεότερη Ελλάδα, είναι επίσης γνωστό και ως βαλσαμόχορτο ή σπαθόχορτο, ενώ, στην ξένη (Αγγλική) βιβλιογραφία, αναφέρεται ως Perforate St John's-wort,[1] Common Saint John's wort και St. John's wort.[Σημ. 1] Στο εξωτερικό, η κοινή ονομασία St John's wort, μπορεί να χρησιμοποιηθεί για να αναφερθεί σε οποιοδήποτε είδος του γένους Hypericum. Συνεπώς, το Υπερικόν το διάτρητον (Hypericum perforatum) προκειμένου να διαφοροποιηθεί, ορισμένες φορές ονομάζεται Common St John's wort ή Perforate St John's wort. Είναι φαρμακευτικό βότανο με αντικαταθλιπτική δράση και ισχυρές αντιφλεγμονώδεις ιδιότητες, ως ένας αραχιδονικός αναστολέας της 5-λιποξυγενάσης (5-LO) και αναστολέας της 1-κυκλοξυγενάσης (COX-1).[2][3][4]
Η ονομασία του γένους «Υπερικόν» (Hypericum), προέρχεται από τις Ελληνικές λέξεις υπέρ (άνωθεν) και εικών (εικόνα), αναφορικά με την παράδοση η οποία υπάρχει, κατά τη διάρκεια της ημέρας του Αγίου Ιωάννη, στο να κρέμονται φυτά επάνω από τις θρησκευτικές εικόνες του σπιτιού, προκειμένου να αποκρουσθεί το κακό. Η Λατινική ονομασία του φυτού «διάτρητον» (perforatum), οφείλεται στο ότι τα φύλλα του έχουν στίγματα, τα οποία είναι εμφανή όταν κρατηθούν μπροστά στο φως, δίνοντάς τους έτσι την «διάτρητη» εμφάνιση. Ονομάζεται σπαθόχορτο, γιατί στην αρχαιότητα το χρησιμοποιούσαν ως επουλωτικό, στις πληγές που γινόντουσαν από τα σπαθιά. Η κοινή του Αγγλική ονομασία St John's wort, προέρχεται από την παραδοσιακή του ανθοφορία και συγκομιδή, που συμβαίνει στις 24 Ιουνίου, κατά την εορτή του Αγίου Ιωάννου.[Σημ. 2]
Το Υπερικόν το διάτρητον (Hypericum perforatum), είναι εγγενές σε τμήματα της Ευρώπης και της Ασίας[5] αλλά έχει εξαπλωθεί και σε ολόκληρο τον κόσμο, ως ένα κοσμοπολίτικο αγριόχορτο εισβολέας, συμπεριλαμβάνοντας τις εύκρατες περιοχές της Ινδίας, Κίνας, Αφρικής και των Ηνωμένων Πολιτειών.
Το βάλσαμο είναι ποώδες πολυετές φυτό (perennial)[Σημ. 3] με εκτεταμένα υφέρποντα ριζώματα (rhizomes).[Σημ. 4] Τα στελέχη του είναι όρθια, διακλαδισμένα στο άνω τμήμα και μπορεί να αυξηθεί σε 1 μ. ύψος. Έχει αντικριστά, άμισχα, [Σημ. 5] στενά, επιμήκη φύλλα, τα οποία έχουν μήκος 1-2 εκ..[6]:176 Τα φύλλα είναι κίτρινο-πράσινου χρώματος, με διάσπαρτα ημιδιαφανή στίγματα του αδενικού ιστού[7] Τα στίγματα είναι εμφανή όταν κρατηθούν μπροστά στο φως, δίνοντας στα φύλλα την «διάτρητη» εμφάνιση στην οποία αναφέρεται η Λατινική ονομασία του φυτού. Τα άνθη φτάνουν σε μήκος τα 2,5 εκατοστά, έχουν πέντε πέταλα (petals)[Σημ. 6] και έχουν φωτεινό κίτρινο χρώμα με εμφανή μαύρα στίγματα.[8]:339 Επίσης, εμφανίζονται σε πλατιά συμπλέγματα ανθέων (cymes)[Σημ. 7] στα άκρα των άνω κλάδων, από τα τέλη της άνοιξης και στις αρχές έως τα μέσα του καλοκαιριού. Τα σέπαλα[Σημ. 8] είναι μυτερά με μαύρα αδενικά στίγματα. Υπάρχουν πολλοί στήμονες,[Σημ. 9] οι οποίοι ενώνονται στη βάση σε τρεις δεσμίδες. Οι κόκκοι γύρης είναι ελλειψοειδείς.[9][Σημ. 10] Όταν συνθλίβονται οι ανθοφόροι οφθαλμοί των ανθέων (όχι αυτά καθεαυτά τα άνθη) ή οι λοβοί των σπόρων, παράγεται ένα ερυθρωπό / πορφυρό υγρό. Περιέχει υπερικίνη και ψευδοϋπερικίνη, φλαβονοειδή (16% στα φύλλα), ξανθόνες, φαινολικά οξέα και αιθέρια έλαια (0,13% σε ολόκληρο το φυτό).
Το βάλσαμο πολλαπλασιάζεται τόσο αγενώς (βλαστικά) όσο και εγγενώς (μέσω σπερμάτων). Ευδοκιμεί στις περιοχές, όπου το μοτίβο της βροχόπτωσης, είναι κυρίαρχο είτε τον χειμώνα είτε το καλοκαίρι. Ωστόσο, η διανομή περιορίζεται από θερμοκρασίες πολύ χαμηλές για την βλάστηση των σπόρων ή την επιβίωση των δενδρυλλίων. Υψόμετρα άνω των 1500 μ., βροχοπτώσεις λιγότερες από 500 χιλ. και μια μέση ημερησία θερμοκρασία Ιανουαρίου (στο Νότιο ημισφαίριο) άνω των 24°C, θεωρούνται περιοριστικά κατώτατα όρια. Ανάλογα με τις περιβαλλοντικές και τις κλιματικές συνθήκες και της ηλικίας του ρόδακα (rosette),[Σημ. 11] το βαλσαμόχορτο θα αλλάξει τη μορφή της ανάπτυξης και τη συνήθεια να προωθήσει την επιβίωση. Οι θερινές βροχές, είναι ιδιαίτερα αποτελεσματικές στο να επιτρέψουν στο φυτό, να αναπτυχθεί βλαστικά, μετά την αποφύλλωση από τα έντομα ή τη βόσκηση. Τα σπέρματα μπορεί να παραμείνουν για δεκαετίες στην τράπεζα σπερμάτων στο έδαφος,[Σημ. 12] τα οποία εκβλασταίνουν έπειτα από διαταραχή (π.χ φωτιά).[10]
Το Υπερικόν το διάτρητον (Hypericum perforatum) καλλιεργείται εμπορικά σε ορισμένες περιοχές της Νοτιοανατολικής Ευρώπης, αν και περιλαμβάνεται ως επιβλαβές ζιζάνιο σε περισσότερες από είκοσι χώρες και έχουν εισαχθεί πληθυσμοί στη Νότια και τη Βόρεια Αμερική, την Ινδία, Νέα Ζηλανδία, Αυστραλία και τη Νότια Αφρική.[10] Στα λιβάδια, το βαλσαμόχορτο δρα τόσο ως τοξικό όσο και ως ζιζάνιο εισβολέας. Αντικαθιστά τις αυτόχθονες φυτικές κοινότητες και την κτηνοτροφική βλάστηση, σε τέτοιο βαθμό, κάνοντας τις παραγωγικές γαίες μη βιώσιμες[11] ή να γίνει ένα είδος εισβολέα στους φυσικούς οικοτόπους και τα οικοσύστηματα. Η κατάποσή του από τα ζώα, μπορεί να προκαλέσει φωτοευαισθησία, καταστολή του κεντρικού νευρικού συστήματος (ΚΝΣ), αυθόρμητη αποβολή και μπορεί να οδηγήσει στο θάνατο.[12] Τα αποτελεσματικά ζιζανιοκτόνα, για τον έλεγχο του Υπερικού (Hypericum) περιλαμβάνουν 2,4-D, picloram και glyphosate. Στη δυτική Βόρεια Αμερική, τρία κολεόπτερα το Chrysolina quadrigemina, Chrysolina hyperici και το Agrilus hyperici, έχουν εισαχθεί ως παράγοντες βιοελέγχου.[13]
Σπορόφυτα.
Άνθος.
Καρπός.
Πλήρες φυτό.
Το υπερικό ή βαλσαμόχορτο απασχόλησε τη θεραπευτική από την αρχαιότητα: ο Γαληνός[14] και ο Διοσκουρίδης[15] το αναφέρουν ως διουρητικό, επουλωτικό, εμμηναγωγό και αιμοστατικό.[16] Στην αρχαιότητα επίσης, το χρησιμοποιούσαν ως επουλωτικό στις πληγές που γινόντουσαν από τα σπαθιά, εξ ου κι η ονομασία του σπαθόχορτο.
Στις ΗΠΑ, μετά από ένα πρόγραμμα του ABC News τον Ιούνιο του 1997, το υπερικό έγινε το πιο δημοφιλές φυτό, το εναλλακτικό «πρόζακ» (Ladose), για την ήπια και μέτρια κατάθλιψη. Χρησιμοποιείται επίσης ως αντισπασμωδικό και βελτιωτικό της ποιότητας του ύπνου σε αϋπνίες. Ήδη, το 1994 στη Γερμανία, συνταγογραφήθηκαν συνταγές για 20 εκατομμύρια ασθενείς. Μόνο στη Μοντάνα των ΗΠΑ καλλιεργούνται σήμερα 500.000 στρέμματα του φυτού.
Σύμφωνα με τη Ευρωπαϊκή Φαρμακοποιία, ως δρόγη νοούνται τα ανθισμένα υπέργεια τμήματα του φυτού, τα οποία περιέχουν ποσοστό μεγαλύτερο του 0,08% σε ολικές υπερικίνες. Τα κατοχυρωμένα από την παραδοσιακή χρήση παρασκευάσματα του βαλσαμόχορτου είναι τα ξηρά εκχυλίσματα (εκχύλιση με οινόπνευμα 38%), τα λεγόμενα βαλσαμέλαια (εκχύλιση με διάφορα φυτικά έλαια όπως ηλιέλαιο, ελαιόλαδο, καλαμποκέλαιο), τα βάμματα (υγρά εκχυλίσματα με αλκοόλη 45-50%) και το αποξηραμένο φυτό για την παρασκευή ροφήματος.[17]
Για συστηματική (εσωτερική) χρήση, λαμβάνεται:
Για τοπική χρήση χρησιμοποιείται κυρίως το βαλσαμέλαιο, το οποίο παρασκευάζεται με εκχύλιση του φρέσκου φυτού σε ελαιόλαδο ή κάποιο άλλο φυτικό λάδι για πολλές ημέρες (40 έως 50).
Η σύσταση των ξηρών εκχυλισμάτων και του βάμματος, διαφέρει σημαντικά από τη σύσταση του βαλσαμελαίου οπότε και οι ενδείξεις καθώς και ο τρόπος χρήσης είναι διαφορετικός.
Το βαλσαμέλαιο είναι ένα εξαιρετικό επουλωτικό και χρησιμοποιείται για την αντιμετώπιση μικρής έκτασης δερματικών φλεγμονών όπως τα ηλιακά εγκάυματα πρώτου βαθμού και οι μικρές πληγές.[18]
Στην παραδοσιακή ιατρική, και ελλείψει του όρου "κατάθλιψη", το βαλσαμόχορτο χρησιμοποιούνταν συστηματικά για την αντιμετώπιση της γενικότερης πνευματικής εξάντλησης και καταπόνησης. Πλήθος μελετών έχουν υποστηρίξει την αποτελεσματικότητα του σπαθόχορτου, ως τη θεραπεία για την κατάθλιψη, ωστόσο τα αποτελέσματα παραμένουν εμπειρικά καθώς ο μηχανισμός δράσης δεν έχει αποσαφηνιστεί.[4][19] Μια ανασκόπηση του 2015 κατέληξε στο συμπέρασμα, ότι έχει μεγαλύτερη αποτελεσματικότητα έναντι του εικονικού φαρμάκου, στη θεραπεία της κατάθλιψης και είναι τόσο αποτελεσματικό, όσο φαρμακευτικές αγωγές ενώ έχει λιγότερες ανεπιθύμητες ενέργειες. Τα συγκεγχυμένα αποτελέσματα των διαφόρων μελετών και οι διακυμάνσεις μεταξύ των χωρών που εκτελέσαν τις μελέτες όσον αφορά την αποτελεσματικότητα, καθιστούν δύσκολο τον χαρακτηρισμό του βαλσαμόχορτου ως αντικαταθλιπτικό παράγοντα.[20][21] Ο μηχανισμός δράσης είναι ακόμα υπό διερεύνηση, παρ'όλα αυτά έχει προταθεί ότι οφείλεται στην αναστολή της επαναπρόσληψης ορισμένων νευροδιαβιβαστών.[9] Σύμφωνα με το National Center for Complementary and Integrative Health (NCCIH) των National Institutes of Health, το βαλσαμόχορτο «μπορεί να βοηθήσει κάποιους τύπους κατάθλιψης, αν και τα στοιχεία δεν είναι οριστικά». Το NCCIH σημειώνει, ότι ο συνδυασμός του σπαθόχορτου, με ορισμένα συνταγογραφόμενα αντικαταθλιπτικά, μπορεί να οδηγήσει σε «δυνητικά απειλητική για τη ζωή, αύξηση της σεροτονίνης», μια εγκεφαλική χημική ουσία, η οποία στοχεύεται από τα αντικαταθλιπτικά.[22] Σε ορισμένες περιπτώσεις στη Γερμανία, συνταγογραφείται για την ήπια έως τη μέτρια κατάθλιψη, ειδικά στα παιδιά και τους εφήβους.[23][24] H ισχυρή παρατηρούμενη αντικαταθλιπτική δράση του φυτού οφείλεται σε ένα πλήθος συστατικών (υπερικίνη, υπεφορίνη φλαβονοειδή) και όχι σε μεμονωμένες ουσίες.[25]
Η υπερικίνη, ψευδοϋπερικίνη και η υπερφορίνη, μπορούν να ποσοτικοποιηθούν στο πλάσμα. Αυτά τα τρία δραστικά συστατικά στους ανθρώπους, έχουν ημιπερίοδο αποβολής του πλάσματος, εντός ενός εύρους από 15-60 ώρες. Κανένα από τα τρία, δεν έχει ανιχνευθεί στα ούρα.[26]
Το βαλσαμόχορτο είναι γενικά καλά ανεκτό, με λίγες παρενέργειες όταν τηρούνται οι προτεινόμενες δοσολογίες.[27] Συχνά οι αναφερόμενες ανεπιθύμητες ενέργειες, περιλαμβάνουν τα γαστροεντερικά συμπτώματα (ναυτία, κοιλιακό άλγος, απώλεια όρεξης και διάρροια), ζάλη, σύγχυση, κόπωση, καταστολή, ξηροστομία, ανησυχία και πονοκέφαλο.[28][29][30] Τα όργανα που πλήτονται από ις ανεπιθύμητες ενέργειες περιλαμβάνονται στο κεντρικό νευρικό σύστημα (ΚΝΣ).[31] Επίσης, το σπαθόχορτο ελαττώνει τα επίπεδα των οιστρογόνων, όπως της οιστραδιόλης, επιταχύνοντας τον μεταβολισμό της και δεν θα έπρεπε να λαμβάνεται από γυναίκες οι οποίες χρησιμοποιούν αντισυλληπτικά χάπια, δεδομένου ότι ρυθμίζει προς τα πάνω το κυτόχρωμα CYP3A4 του συστήματος Ρ450 στο ήπαρ.[32] Το βαλσαμόχορτο όταν χορηγείται μόνο του σπανίως μπορεί να προκαλέσει φωτοευαισθησία φωτοδερματίτιδα. Αυτό μπορεί να οδηγήσει σε ευαισθησία στο φως και στα ηλιακά εγκαύματα.[27] Η φωτοτοξικότητα του σπαθόχορτου είναι κατά πολύ μικρότερη της καθαρής υπερικίνης. Το βαλσαμόχορτο, συνδέεται με επιβαρυντική ψύχωση σε άτομα που έχουν σχιζοφρένεια.[33] Σε περίπτωση που λαμβάνονται άλλα φάρμακα, πρέπει να ενημερώνεται ο γιατρός ή ο φαρμακοποιός.
Το βαλσαμόχορτο αλληλεπιδρά με διάφορα φάρμακα είτε ελαττώνοντας την αποτελεσματικότητα τους ειτε προκαλώντας ανεπιθύμητες ενέργειες. Ο μηχανισμός πιστεύεται ότι περιλαμβάνει την επαγωγή του κυτοχρώματος P450 των ενζύμων CYP3A4 και CYP1A2 (μόνο γυναίκες), που έχει ως αποτέλεσμα την αύξηση του μεταβολισμού ορισμένων φαρμάκων, οδηγώντας σε μειωμένη συγκέντρωση τους στο πλάσμα.[34] Επιπλέον, τα συστατικά του σπαθόχορτου επάγουν την P-γλυκοπρωτεΐνη. Αυξημένη έκφρασης της Ρ-γλυκοπρωτεΐνης οδηγεί σε σε μειωμένη απορρόφηση και αυξημένο ρυθμό απέκκρισης ορισμένων φαρμάκων, που οδηγεί σε χαμηλότερη συγκέντρωση στο πλάσμα και μείωση της κλινικής αποτελεσματικότητας.[35] Έχει βρεθεί ότι η χρήση του σπαθόχορτου, μειώνει την αποτελεσματικότητα των αντισυλληπτικών χαπιών,[36] των φαρμάκων για την αντιμετώπιση του ιού HIV, των αντιπηκτικών φαρμάκων όπως είναι η βαρφαρίνη, των φαρμάκων για τη μείωση της χοληστερόλης και των αγωγών που χρησιμοποιούνται μετά τη μεταμόσχευση.[37]
Αλληλεπιδρά με αντικαταθλιπτικά φάρμακα της κατηγορίας των Αναστολέων Επαναπρόσληψης Σεροτονίνης και Νορεπινεφρίνης (σιταλοπράμη, φλουοξετίνη, παροξετίνη, σερτραλίνη, εσκιταλοπράμη, φλουβοξαμίνη) οδηγώντας σε αύξηση των επιπέδων σεροτονίνης, προκαλώντας το σύνδρομο σεροτονίνης που είναι μια δυνητικά απειλητική γιατη ζωή ανεπιθύμητη ενέργεια.[38][39] Η κατανάλωση του βαλσαμόχορτου αποθαρρύνεται για τα άτομα με διπολική διαταραχή. Υπάρχει έντονος προβληματισμός ότι οι άνθρωποι με διπολική κατάθλιψη, λαμβάνοντας βαλσαμόχορτο, μπορεί να διατρέχουν υψηλότερο κίνδυνο για επεισόδια μανίας.[40]
Το σπαθόχορτο, παρομοίως με άλλα βότανα, περιέχει μια ολόκληρη σειρά από διαφορετικά χημικά συστατικά, στα οποία μπορεί να οφείλονται οι ποικίλλες φαρμακολογικές του δράσεις.[41] Η υπερφορίνη και αδυπερφορίνη, είναι αγωνιστές των υποδοχέων TRPC6 και ως εκ τούτου, θα προκαλέσουν μη ανταγωνιστική αναστολή επαναπρόσληψης μονοαμινών (συγκεκριμένα, ντοπαμίνη, νορεπινεφρίνη και σεροτονίνη), GABA και το γλουταμινικό οξύ, όταν ενεργοποιήσουν αυτό το κανάλι ιόντων.[19][42][43] Στους ανθρώπους, το δραστικό συστατικό η αδυπερφορίνη, είναι επίσης ένας αναστολέας του PTGS1, αραχιδονικό 5-λιποξυγενάσης, SLCO1B1 και επαγωγέας του cΜΟΑΤ.[42][43][44] Η υπερφορίνη είναι επίσης μια αντι-φλεγμονώδης ένωση με αντιαγγειογενετικές, αντιβιοτικές και νευροτροφικές ιδιότητες.[42][43][44] Η υπερφορίνη έχει επίσης ένα ανταγωνιστικό αποτέλεσμα επί των υποδοχέων NMDA, έναν τύπο υποδοχέα γλουταμικού.[43] Επιπλέον, το σπαθόχορτο είναι γνωστό ότι ρυθμίζει προς τα κάτω τον β1 αδρενοϋποδοχέα και ρυθμίζει προς τα πάνω τους μετασυναπτικούς υποδοχείς 5-ΗΤ1Α και 5-ΗΤ2Α, αμφότερους να είναι ένα είδος υποδοχέα σεροτονίνης.[19] Άλλες ενώσεις, μπορούν επίσης να διαδραματίσουν κάποιο ρόλο, ως προς τις αντικαταθλιπτικές επιπτώσεις του βαλσαμόχορτου, τέτοιες ενώσεις περιλαμβάνουν: ολιγομερείς προκυανιδίνες, φλαβονοειδή (κουερσετίνη), υπερικίνη και ψευδοϋπερικίνη.[19][45][46][47]
Σε μεγάλες δόσεις, το βαλσαμόχορτο είναι δηλητηριώδες για τα ζώα που βόσκουν (βοοειδή, πρόβατα, κατσίκες, άλογα).[11] Συμπεριφορικά σημάδια της δηλητηρίασης, είναι η γενική ανησυχία και ο ερεθισμός του δέρματος. Η ανησυχία συχνά υποδεικνύεται από το τρίψιμο της οπλής στο έδαφος, το κούνημα ή και το τρίψιμο της κεφαλής και την περιστασιακή αδυναμία του οπισθίου άκρου με την κλείδωση επάνω??? (knuckling over), το λαχάνιασμα, τη σύγχυση και την κατάθλιψη. Η μανία και η υπερκινητικότητα μπορεί επίσης να καταλήξει, συμπεριλαμβάνοντας το τρέξιμο σε κύκλους έως την εξάντληση. Οι παρατηρήσεις των πυκνών παρασιτώσεων του βαλσαμόχορτου από τα Αυστραλιανά φυτοφάγα οικόσιτα, περιλαμβάνουν την εμφάνιση κυκλικών μπαλωμάτων, δίνοντας στις πλαγιές μια εμφάνιση «καλλιέργειας κύκλου», η οποία τεκμαίρεται από αυτό το φαινόμενο. Τα ζώα συνήθως αναζητούν τη σκιά και έχουν μειωμένη όρεξη. Έχει σημειωθεί υπερευαισθησία στο νερό και μπορεί να εμφανιστούν σπασμοί μετά από ένα χτύπημα στο κεφάλι. Αν και έχει σημειωθεί η γενική αποστροφή προς το νερό, ορισμένοι μπορεί να το αναζητήσουν προς ανακούφιση.
Σοβαρός ερεθισμός του δέρματος είναι φυσικά προφανής, με κοκκίνισμα των μη-χρωματισμένων και απροστάτευτων περιοχών. Στη συνέχεια, αυτό οδηγεί στη φαγούρα και το τρίψιμο, που ακολουθείται από περαιτέρω φλεγμονή, εξίδρωση και το σχηματισμό κάκαρου. Οι βλάβες και η φλεγμονή που λαμβάνουν χώρα, λέγεται ότι μοιάζουν με τις συνθήκες που φαίνονται στον αφθώδη πυρετό. Έχουν παρατηρηθεί πρόβατα με οίδημα προσώπου, δερματίτιδα και πτώση του μαλλιού, που οφείλεται στην τριβή. Τα γαλακτοφόρα ζώα μπορεί να παύσουν ή να έχουν μειωμένη παραγωγή γάλακτος· τα κυοφορούντα ζώα μπορεί να αποβάλουν. Οργανικές βλάβες στους μαστούς των ζώων, είναι συχνά εμφανείς. Τα άλογα μπορεί να δείξουν σημάδια ανορεξίας, κατάθλιψης (με μια κωματώδη κατάσταση), διεσταλμένες κόρες και εγχεόμενη επιπεφυκότα.
Συνήθως παρατηρούνται, αυξημένη αναπνοή και καρδιακός ρυθμός, ενώ ένα από τα πρώτα σημάδια της δηλητηρίασης του βαλσαμόχορτου, είναι μια ανώμαλη αύξηση στη θερμοκρασία του σώματος. Τα προσβαλλόμενα ζώα, θα απολέσουν βάρος ή θα αποτύχουν να ανακτήσουν βάρος· τα νεαρά ζώα επηρεάζονται περισσότερο από ό, τι τα γηραιότερα ζώα. Σε σοβαρές περιπτώσεις, μπορεί να επέλθει ο θάνατος, ως άμεσο αποτέλεσμα της πείνας ή λόγω της δευτερογενούς ασθένειας ή σηψαιμίας των οργανικών βλαβών. Ορισμένα προσβεβλημένα ζώα, μπορεί να πνιγούν κατά λάθος. Κακές επιδόσεις των αμνών που θηλάζουν (κεχρωσμένων και μη κεχρωσμένων) έχει παρατηρηθεί, γεγονός που υποδηλώνει μια μείωση στην παραγωγή γάλακτος ή τη μετάδοση μιας τοξίνης εντός αυτού.
Τα περισσότερα κλινικά συμπτώματα στα ζώα, προκαλούνται από φωτοευαισθησία.[97] Τα φυτά μπορούν να προκαλέσουν είτε πρωτοβάθμια είτε δευτεροβάθμια φωτοευαισθησία:
Οι Araya και Ford (1981), διερεύνησαν τις αλλαγές στη λειτουργία του ήπατος και κατέληξαν στο συμπέρασμα ότι δεν υπάρχουν αποδεικτικά στοιχεία του Hypericum που να σχετίζονται με την επίδραση στην ικανότητα απέκκρισης του ήπατος ή η οποιαδήποτε παρεμβολή ήταν ελάχιστη και προσωρινή. Ωστόσο, στοιχεία της ηπατικής βλάβης στο πλάσμα αίματος, έχουν βρεθεί στις υψηλές και μακρές τιμές της δόσης.
Η φωτοευαισθησία προκαλεί φλεγμονή του δέρματος από ένα μηχανισμό που περιλαμβάνει μια χρωστική ή φωτοδυναμική ένωση, η οποία όταν ενεργοποιείται από ένα συγκεκριμένο μήκος κύματος του φωτός οδηγεί σε in vivo αντιδράσεις οξειδοαναγωγής. Αυτό οδηγεί σε αλλοιώσεις των ιστών, ιδιαίτερα αισθητές πάνω και γύρω σε περιοχές του δέρματος που εκτίθενται στο φως. Ελαφρώς καλυπτόμενες ή κακώς κεχρωσμένες περιοχές είναι πιο εμφανείς. Αφαίρεση των προσβεβλημένων ζώων από τα αποτελέσματα του ηλιακού φωτός, στα μειωμένα συμπτώματα δηλητηρίασης.
Από το υπερικό έχουν απομονωθεί ουσίες που ανήκουν στις παρακάτω κατηγορίες:[41][49]
Οι ναφθοδιανθρόνες υπερικίνη και ψευδοϋπερικίνη, μαζί με την φλορογλουκινόλη παράγωγο υπερφορίνης, πιστεύεται ότι είναι μεταξύ των πολυάριθμων δραστικών συστατικών.[9][98][99][100] Περιέχει επίσης αιθέρια έλαια, που αποτελούνται κυρίως από σεσκιτερπένια.[9]
Το βάλσαμόχορτο, μελετάται για την αποτελεσματικότητα στη θεραπεία ορισμένων διαταραχών σωματοποίησης. Τα αποτελέσματα από τις αρχικές μελέτες, είναι ανάμικτα και ακόμα μη τελεσίδικα; κάποιες έρευνες δεν έχουν βρει καμία αποτελεσματικότητα, άλλη έρευνα διαπίστωσε μια μικρή ελάφρυνση των συμπτωμάτων. Περαιτέρω μελέτη απαιτείται και διεξάγεται.
Ένα σημαντικό συστατικό των χημικών, η υπερφορίνη, μπορεί να είναι χρήσιμη για τη θεραπεία του αλκοολισμού, αν και η δοσολογία, η ασφάλεια και η αποτελεσματικότητα δεν έχουν μελετηθεί.[101][102] Η υπερφορίνη έχει επίσης εμφανίσει αντιβακτηριακές ιδιότητες έναντι Gram-θετικών βακτηρίων, αν και δεν έχει μελετηθεί η δοσολογία, η ασφάλεια και η αποτελεσματικότητα.[103] Η βοτανική ιατρική έχει επίσης χρησιμοποιήσει εκχυλίσματα λιπόφιλων από το βάλσαμόχορτο, ως τοπική θεραπεία για πληγές, εκδορές, εγκαύματα και τον πόνο των μυών.[102] Τα θετικά αποτελέσματα που έχουν παρατηρηθεί, γενικά αποδίδονται στην υπερφορίνη, λόγω των πιθανών αντιβακτηριακών και αντι-φλεγμονωδών αποτελεσμάτων της.[102] Για το λόγο αυτό, η υπερφορίνη μπορεί να είναι χρήσιμη, στη θεραπεία των μολυσμένων πληγών και των φλεγμονωδών νόσων του δέρματος.[102] Εις απάντηση της ενσωμάτωσης της υπερφορίνης σε ένα νέο λάδι μπάνιου, διεξήχθη μια μελέτη, για να αξιολογήσει το δυναμικό ερεθισμού του δέρματος και η οποία βρήκε καλή ανεκτικότητα του δέρματος απέναντι στο βάλσαμόχορτο.[102]
Η υπερικίνη και η ψευδοϋπερικίνη έχουν δείξει τόσο αντιιικές όσο και αντιβακτηριακές δραστικότητες. Πιστεύεται, ότι αυτά τα μόρια προσδένονται μη ειδικά, με ιικές και κυτταρικές μεμβράνες και μπορεί να οδηγήσει σε φωτο-οξείδωση των παθογόνων και να τις σκοτώσει.[9]
Το Υπερικόν το διάτρητον (Hypericum perforatum) ή κοινώς το βάλσαμο, είναι ανθοφόρο φυτό του γένους Υπερικόν (Hypericum), της οικογένειας Υπερικίδες (Hypericaceae).
Στην Αρχαία Ελλάδα, ήταν γνωστό ως «υπερικόν», ενώ στη νεότερη Ελλάδα, είναι επίσης γνωστό και ως βαλσαμόχορτο ή σπαθόχορτο, ενώ, στην ξένη (Αγγλική) βιβλιογραφία, αναφέρεται ως Perforate St John's-wort, Common Saint John's wort και St. John's wort. Στο εξωτερικό, η κοινή ονομασία St John's wort, μπορεί να χρησιμοποιηθεί για να αναφερθεί σε οποιοδήποτε είδος του γένους Hypericum. Συνεπώς, το Υπερικόν το διάτρητον (Hypericum perforatum) προκειμένου να διαφοροποιηθεί, ορισμένες φορές ονομάζεται Common St John's wort ή Perforate St John's wort. Είναι φαρμακευτικό βότανο με αντικαταθλιπτική δράση και ισχυρές αντιφλεγμονώδεις ιδιότητες, ως ένας αραχιδονικός αναστολέας της 5-λιποξυγενάσης (5-LO) και αναστολέας της 1-κυκλοξυγενάσης (COX-1).
Кантарион (латински: hypericum perforatum) — повеќегодишна тревна билка од истоимената фамилија (Hypericaceae).
Кантарион е повеќегодишна тревна билка со разгранет корен. Стеблото е исправено, без лисја, со висината од 20 до 100 сантиметри. Цветовите се жолти, додека плодот е како ѕвонче. Цвета од мај до септември.
За да биде добро одгледано, земјиштето треба да биде средно богато со хранливи материи, топлината треба да е умерена како и светлината. Поради тоа, кантарионот најмногу успева во умерени предели и суптропска клима ширум светот. Кантарионот се состои од: хиперицин, изохиперицин, хиперозид, кверцетин, рутин, кверцитрин, биапигенин, аменофлавон, катехин, епикатехин, хлорогенска киселина, кафена киселина, хиперфлорин, каротеноиди, стероли, леукоаноцијани, етерично масло.
Kантарионот се користи како антидепресив, седатив и антибиотик, се користи надворешно и внатрешно. Активна супстанца е хиперфлорин. Екстрактот од кантарион ја зголемува концентрацијата неуротрансмитера седатив и на адреналин во синапсите. Маслото од кантарион (Oleum hyperici) e најшироко познато и се користи за ублажување и лечење на изгореници. Се добива со преливање на свежи цветови на кантарионот со маслиново масло. Кантарионовото масло се користи за надворешна употреба и за јадење. Освен тоа може да ја штити кожата од воспалениe, помага и ја негува сувата и испуканата кожа и може да се употребува и за масажа преку опуштање на мускулите и помага кај слабата циркулација. Маслото од кантарион не треба да се користи за заштита од сонце, бидејќи е фотосензитивно и може да предизвика промени на кожата, но при изгореници истото може да биде користено.
При истражувања спроведени во 2015 година во врска со антидепресивното дејство на кантарионот, било утврдено дека не е ефективен како други антидепресиви, и дека лекувањето од депресија со кантарион се должи на плацебо ефектот.[1]
Кантарионот е отровен за добитокот.[2]
Кантарион (латински: hypericum perforatum) — повеќегодишна тревна билка од истоимената фамилија (Hypericaceae).
Чойкаҳак– Hypericum perforatum (Зверобой продырявленный).
Чойкаҳак – растании бисёрсола буда, баландиаш то 1 метр мешавад.
Решааш – тиррешаи сернавда мешавад.
Пояаш – ростистодаи суфтаи дуќиррадор мебошад.
Баргҳояш – нишастаи мутаќобил, шаклашон – эллепсшакл ё ки камтар дарози – байзашакл (дар дарози 0,7-3,5 см ва дар паҳни 0,2-1,5 см) буда, дар танаи худ нуќтаҳои равғанини ғадуддор дорад, лаби паҳнаки барг сиҳати яклухт мебошад.
Хӯшагул – ҳорӯбаки - сипаршакли бисёргула.
Рангаш – зарди тилодор, гулбаргаш – 5 то дарози-эллепсшакл (1-2 см дар дарозӣ ва 0,4-0,5 см дар паҳнӣ) бо нуќтаҳои майдаи сиёҳи ғадуддор мебошад.
Мевааш – ќутичаи сеќисмае мебошад, ки дар дарунаш бисёр тухм ҷойгир шудааст (аз 45 то 100 дона).
Тухмаш – майдачаи дарозрӯя ё ки слиндршакл, рангаш ҷигарии-торик, дарозиашон то 1 мм мебошад. Вазни 1000 дона тухмӣ ба 0,10 -0,15 грамм баробар мебошад.
Чойкаҳак моҳҳои май-июл гул карда, моҳҳои сентябр-октябр тухм медиҳад.Чойкаҳак дар нишебиҳои адирҳо, лаби ҷӯйбору дарёчаҳо, байни алафзорҳо дар ҷойҳои серофтоби ноҳияҳои Зарафшон, Туркистон, Ҳисору – Дарвоз, Ҷанубу-Шарќи Тоҷикистон дар баландии 600-3000 метр мерӯяд.
Дар тиб қисми болоии гулкардаи растаниро истифода мебаранд. Аз даври ќадим чойкаҳакро ҳамчун растании дорувор истифода мебурданд. Чойкаҳакро аз бисёр бемориҳо истифода мебаранд, ҳамчун: зидди газаки гурда ва меъда ҳамчун ҷойҳои маҳкамшударо мекушодагӣ. Тухмии чойкаҳак меъдаро мустаҳкам менамояд ва дар ваќти касалиҳои дил ва ғайра истифода бурда мешавад. Чойкаҳак иштиҳои одамро нағз карда, кори рўдаҳоро нағз мекунад ва пешобро медавонад. Препаратҳои галенӣ, ки аз алафи чойкаҳак тайёр карда мешаванд ҳамчун хунманъкунанда ва зидди газзак истифода мебаранд.
Бо методи фармокологӣ исбот карда шудааст, ки алафи чойкаҳак ба худ хусусиятҳои давондани пешоб ва нест кардани кирмҳоро дорад. Шароби 10% ин алаф зидди острицаҳо (гименолепидоза) истифода мебаранд. Дар ветеринария аз шароби 20% -и алафи чойкаҳак эмульсияро дар асоси равғани вазелин тайёр карда, бо он захмҳои чорворо табобат менамоянд.
Сатторов Ҷ.С. Растаниҳои доруворӣ. Курси мухтасари лексия аз фанни «Растаниҳои доруворӣ». – Душанбе, 2007
Чойкаҳак– Hypericum perforatum (Зверобой продырявленный).
Чойкаҳак – растании бисёрсола буда, баландиаш то 1 метр мешавад.
Һары мәтрүшкә (рус. Зверобо́й продыря́вленный, Зверобо́й обыкнове́нный, лат. Hypéricum perforátum) — күп йыллыҡ үлән үҫемлек, бейеклеге 30-100 см. Июндән алып авгусҡа тиклем һары сәскә ата, июнь-сентябрҙә орлоғо өлгөрә.
Европала Атлантик океандан алып Себер, Монголия, Ҡытайға тиклем таралған. Төньяҡ Африкала осрай. Күсерелгән үҫемлек булараҡ Яңы Зеландия, Япония, Төньяҡ һәм Көньяҡ Америкала үҫә. Үҫемлек урман ситендә, туғайҙарҙа, урман яландарҙа үҫә. Башҡортостанда киң таралған, бигерәк тә Көньяҡ Уралда күпләп осрай.
Дауаға ярағаны борондан билдәле.
Дарыуға уның япрағы ваҡ ҡына тишеклеһен ҡулланалар. Уның составында дуплау матдәләре, эфир майы, β-ситостерин, тритерпен (сапонин), С витамины , E, флавоноид (гиперозид, рутин), антрахинон, макро- һәм микроэлемент һәм башҡа биологик актив матдәләр, гиперицин буяу матдәһе бар.
Төнәтмәһен, настойкаһын ашҡаҙан-эсәк ауырыуҙарын, бауыр һәм үт ҡыуығын дауалағанда ҡулланлар, тамаҡ шешкәндә һарҡынтыһы менән сайҡаталар. Бөйөр, артрит, радикулит булғанда ла ҡулланалар. Ҡатын-ҡыҙ ауырыуҙары, балаларҙа диатез булғанда файҙаһы тейә. Үпкә туберкулеҙы булғанда ыңғай йоғонтоһо күҙәтелә. Халыҡ медицинаһында башҡа бик күп сирҙәргә ҡаршы ла файҙаланалар.
Һары мәтрүшкәне башҡа төр дарыуҙар эскәндә бик һаҡ ҡулланырға кәрәк. Беренсе сиратта иммуносупрессанттар менән бер ваҡытта эсеү тыйыла.
Һары мәтрүшкә (рус. Зверобо́й продыря́вленный, Зверобо́й обыкнове́нный, лат. Hypéricum perforátum) — күп йыллыҡ үлән үҫемлек, бейеклеге 30-100 см. Июндән алып авгусҡа тиклем һары сәскә ата, июнь-сентябрҙә орлоғо өлгөрә.
Hypericum perforatum, known as St. John's wort,[1] is a flowering plant in the family Hypericaceae and the type species of the genus Hypericum.
Possibly a hybrid between H. maculatum and H. attenuatum, the species can be found across temperate areas of Eurasia and has been introduced as an invasive weed to much of North and South America, as well as South Africa and Australia. While the species is harmful to livestock and can interfere with prescription drugs, it has been used in folk medicine over centuries, and remains commercially cultivated in the 21st century. Hyperforin, a phytochemical constituent of the species, is under basic research for possible therapeutic properties.
Hypericum perforatum is an herbaceous perennial plant with extensive, creeping rhizomes. Its reddish stems are erect and branched in the upper section, and can grow up to 1 metre (3 feet 3 inches) high. The stems are woody near their base and may appear jointed from leaf scars.[2] The branches are typically clustered about a depressed base. It has opposite and stalkless leaves that are narrow and oblong in shape and 1–2 centimetres (1⁄2–3⁄4 in) long.[3] Leaves borne on the branches subtend the shortened branchlets. The leaves are yellow-green in color, with scattered translucent dots of glandular tissue.[4] The dots are conspicuous when held up to the light, giving the leaves a perforated appearance. The flowers measure up to 2.5 cm (1 in) across, have five petals and sepals, and are colored bright yellow with conspicuous black dots.[5] The flowers appear in broad helicoid cymes at the ends of the upper branches, between late spring and early to mid-summer. The cymes are leafy and bear many flowers. The pointed sepals have black glandular dots. The many stamens are united at the base into three bundles. The pollen grains are ellipsoidal.[6] The black and lustrous seeds are rough, netted with coarse grooves.[7]
When flower buds (not the flowers themselves) or seed pods are crushed, a reddish or purple liquid is produced.[8]
Full plant
Seedlings
Translucent dots of glandular tissue on the leaves
Blossom
Fruit
The plant contains the following:[9][10]
The naphthodianthrones hypericin and pseudohypericin along with the phloroglucinol derivative hyperforin are thought to be among the numerous active constituents.[6][11][12][13] It also contains essential oils composed mainly of sesquiterpenes.[6]
Pseudohypericin
Kielcorin
Norathyriol
Hypericin, pseudohypericin, and hyperforin may be quantitated in plasma as confirmation of usage and to estimate the dosage. These three active substituents have plasma elimination half-lives within a range of 15–60 hours in humans. None of the three has been detected in urine specimens.[14]
It is probable that H. perforatum originated as a hybrid between two closely related species with subsequent doubling of chromosomes. One species is certainly a diploid a subspecies of H. maculatum, either subspecies maculatum or immaculatum. Subspecies maculatum is similar in distribution and hybridizes easily with H. perforatum, but subspecies immaculatum is more similar morphologically. The other parent is most likely H. attenuatum as it possesses the features of H. perforatum that H. maculatum lacks. Though H. maculatum is mostly western in its distribution across Eurasia and Hypericum attenuatum is mostly eastern, both species share distribution in Siberia, where hybridization likely took place. However, the subspecies immaculatum now only occurs in south-east Europe.[15]
The specific epithet perforatum is Latin, referring to the perforated appearance of the plant's leaves.[7]
The common name "St John's wort" may refer to any species of the genus Hypericum. Therefore, Hypericum perforatum is sometimes called "common St John's wort" or "perforate St John's wort" to differentiate it.
St John's wort is named as such because it commonly flowers, blossoms and is harvested at the time of the summer solstice in late June, around St John's Feast Day on 24 June. The herb would be hung on house and stall doors on St John's Feast day to ward off evil spirits and to safeguard against harm and sickness to people and live-stock. Alternatively, there may be a connection with the Knights Hospitaller. The genus name Hypericum is possibly derived from the Greek words hyper (above) and eikon (picture), in reference to the tradition of hanging plants over religious icons in the home during St John's Day.
H. perforatum is native to temperate parts of Europe and Asia, but has spread to temperate regions worldwide as a cosmopolitan invasive weed.[16][17] It was introduced to North America from Europe.[18] The species thrives in areas with either a winter- or summer-dominant rainfall pattern; however, distribution is restricted by temperatures too low for seed germination or seedling survival.[16] Altitudes greater than 1,500 metres (4,900 ft), rainfall less than 500 millimetres (20 in), and daily mean temperatures greater than 24 °C (75 °F) are considered limiting thresholds.[19]
The flower occurs in prairies, pastures, and disturbed fields. It prefers sandy soils.[2]
St John's wort reproduces both vegetatively and sexually. Depending on environmental and climatic conditions, and rosette age, St John's wort will alter growth form and habit to promote survival. Summer rains are particularly effective in allowing the plant to grow vegetatively, following defoliation by insects or grazing.[19] The seeds can persist for decades in the soil seed bank, germinating following disturbance.[20]
H. perforatum is affected by phytoplasma diseases, and when infected with Candidatus phytoplasma fraxini it undergoes several phytochemical changes and shows visible symptoms, including yellowing and witches' bloom symptoms. Naphthodianthrone, flavonoid, amentoflavone, and pseudohypericin levels are reduced; chlorogenic acid levels increased. Additionally, phytoplasma diseases greatly reduced the essential oil yield of the plant.[21]
Although H. perforatum is grown commercially in some regions of southeast Europe, it is listed as a noxious weed in more than twenty countries and has introduced populations in South and North America, India, New Zealand, Australia, and South Africa.[16][20] In pastures, St John's wort acts as both a toxic and invasive weed. It replaces native plant communities and forage vegetation to the extent of making productive land nonviable or becoming an invasive species in natural habitats and ecosystems.[22] Ingestion by livestock such as horses, sheep, and cattle can cause photosensitization, central nervous system depression, spontaneous abortion, or death.[22][23] Effective herbicides for control of Hypericum perforatum include 2,4-D, picloram, and glyphosate. In western North America the beetles Chrysolina quadrigemina, C. hyperici, and Agrilus hyperici have been introduced as biocontrol agents.[24]
In large doses, St John's wort is poisonous to grazing livestock.[22] Behavioral signs of poisoning are general restlessness and skin irritation. Restlessness is often indicated by pawing of the ground, headshaking, head rubbing, and occasional hindlimb weakness with knuckling over, panting, confusion, and depression. Mania and hyperactivity may also result, including running in circles until exhausted. Observations of thick wort infestations by Australian grazers include the appearance of circular patches giving hillsides a "crop circle" appearance, it is presumed, from this phenomenon. Animals typically seek shade and have reduced appetites. Hypersensitivity to water has been noted, and convulsions may occur following a knock to the head. Although general aversion to water is noted, some may seek water for relief.
Severe skin irritation is physically apparent, with reddening of non-pigmented and unprotected areas. This subsequently leads to itch and rubbing, followed by further inflammation, exudation, and scab formation. Lesions and inflammation that occur are said to resemble the conditions seen in foot and mouth disease. Sheep have been observed to have face swelling, dermatitis, and wool falling off due to rubbing. Lactating animals may cease or have reduced milk production; pregnant animals may abort. Lesions on udders are often apparent. Horses may show signs of anorexia, depression (with a comatose state), dilated pupils, and injected conjunctiva.
Increased respiration and heart rate is typically observed while one of the early signs of St John's wort poisoning is an abnormal increase in body temperature. Affected animals will lose weight, or fail to gain weight; young animals are more affected than old animals. In severe cases death may occur, as a direct result of starvation, or because of secondary disease or septicaemia of lesions. Some affected animals may accidentally drown. Poor performance of suckling lambs (pigmented and non-pigmented) has been noted, suggesting a reduction in milk production, or the transmission of a toxin in the milk. It may result in an undesirable flavor.[25]
St John's wort may cause allergic reactions and can interact with some prescription drugs.[26][27] St John's wort is generally well-tolerated, but it may cause gastrointestinal discomfort (such as nausea, abdominal pain, loss of appetite, and diarrhoea), dizziness, confusion, fatigue, sedation, dry mouth, restlessness, headache and hypertension.[26][28][29][10]
The organ systems associated with adverse drug reactions to St John's wort and fluoxetine have a similar incidence profile;[30] most of these reactions involve the central nervous system.[30] St John's wort also decreases levels of estrogens, such as estradiol, by accelerating its metabolism, and women on contraceptive pills are not advised to take it.[27] St. John's wort should not be taken by women during pregnancy or breast-feeding.[26]
Common St John's wort has been used in herbalism for centuries.[27][26] It was thought to have medical properties in classical antiquity and was a standard component of theriacs, from the Mithridate of Aulus Cornelius Celsus' De Medicina (c. 30 CE) to the Venice treacle of d'Amsterdammer Apotheek in 1686. Folk usages included oily extract (St John's oil) and Hypericum snaps. Hypericum perforatum is a common species and is grown commercially for use in herbalism and traditional medicine.[26]
The red, oily extract of H. perforatum has been used in the treatment of wounds, including by the Knights Hospitaller, the Order of St John.[27][31] Both hypericin and hyperforin are under study for their potential antibiotic properties.[32]
A 2015 meta-analysis review concluded that it has superior efficacy to placebo in treating depression, is as effective as standard antidepressant pharmaceuticals for treating depression, and has fewer adverse effects than other antidepressants.[34] The authors concluded that it is difficult to assign a place for St. John's wort in the treatment of depression owing to limitations in the available evidence base, including large variations in efficacy seen in trials performed in German-speaking countries relative to other countries. In Germany, St. John's wort may be prescribed for mild to moderate depression, especially in children and adolescents.[35] A 2008 Cochrane review of 29 clinical trials concluded that it was superior to placebo in patients with major depression, as effective as standard antidepressants and had fewer side-effects.[36] A 2016 review noted that use of St. John's wort for mild and moderate depression was better than placebo for improving depression symptoms, and comparable to antidepressant medication.[37] A 2017 meta-analysis found that St. John's wort had comparable efficacy and safety to SSRIs for mild-to-moderate depression and a lower discontinuation rate.[38]
Some studies and research reviews have supported the efficacy of St John's wort as a treatment for depression in humans. [27]
In the United States, St John's wort is considered a dietary supplement by the FDA, and is not regulated by the same standards as a prescription drug.[39][40] According to the United States National Center for Complementary and Integrative Health, St. John's wort appears to be more effective than placebo and as effective as standard antidepressant medications for mild and moderate depression, and that it is uncertain whether this is true for severe depression or for longer than 12 weeks.[27] Supplement strength varies by manufacturer and possibly by batch.[41] With antidepressants, one "may have to try a few before finding what works best," notes the United States National Library of Medicine.[42]
In China, St. John's wort combined with Eleutherococcus senticosus is sold as an antidepressant under the name Shugan Jieyu Jiaonang (Chinese: 舒肝解郁胶囊; pinyin: Shūgān Jiěyù Jiāonáng; lit. 'Liver Soothing Depression Relief Capsules'), according to the Pharmacopoeia of the People's Republic of China. The pharmacopoeia states in Chinese that it is used "for mild and moderate unipolar depression".[43]
St John's wort, similarly to other herbs, contains different phytochemical constituents.[9][44][45] Although St. John's wort is sold as a dietary supplement, there are no standardized manufacturing procedures, and some marketed products may be contaminated with metals, fillers or other impurities.[26]
Notes:
Besides its allergenic effects, St John's wort can interfere (in potentially life-endangering ways) with the effects of many prescription drugs,[27][26] including the anti-psychotics risperidone and 9-hydroxyrisperidone (i.e. paliperidone, Xeplion or Invega),[48][49] cyclosporine, digoxin, HIV drugs, cancer medications including irinotecan, and warfarin.[27][26] Combining both St John's wort and antidepressants could lead to increased serotonin levels causing serotonin syndrome.[50] It should not be taken with the heart medication ranolazine.[51] Combining estrogen-containing oral contraceptives with St John's wort can lead to decreased efficacy of the contraceptive and, potentially, unplanned pregnancies.[52] Consumption of St John's wort is discouraged for those with bipolar disorder, schizophrenia or dementia, and for people using dietary supplements, headache medicine, anticoagulants, and birth control pills.[27][26]
St John's wort has been shown to cause multiple drug interactions through induction of the cytochrome P450 enzymes CYP3A4 and CYP1A2. This drug-metabolizing enzyme induction results in the increased metabolism of certain drugs, leading to decreased plasma concentration and potential clinical effect.[53] The principal constituents thought to be responsible are hyperforin and amentoflavone. There is strong evidence that the mechanism of action of these interactions is activation of the pregnane X receptor.[54]
St John's wort has also been shown to cause drug interactions through the induction of the P-glycoprotein efflux transporter. Increased P-glycoprotein expression results in decreased absorption and increased clearance of certain drugs, leading to lower plasma concentrations and impaired clinical efficacy.[49]
Hypericum perforatum, known as St. John's wort, is a flowering plant in the family Hypericaceae and the type species of the genus Hypericum.
Possibly a hybrid between H. maculatum and H. attenuatum, the species can be found across temperate areas of Eurasia and has been introduced as an invasive weed to much of North and South America, as well as South Africa and Australia. While the species is harmful to livestock and can interfere with prescription drugs, it has been used in folk medicine over centuries, and remains commercially cultivated in the 21st century. Hyperforin, a phytochemical constituent of the species, is under basic research for possible therapeutic properties.
Trapunkta hiperiko aŭ sankt-johana herbo (Hypericum perforatum) estas kuracplanto, kiun laŭtradicie oni elŝiru dum la nokto de sankta-Johano festo, je la somera solstico.
Sur la rando de la vojetoj, en senkulturejoj, hiperiko trapunktata leviĝas ĝis 60 centimetroj de alteco. Plurjara planto kun rigida kaj branĉplena tigo, ĝi eligas varman kaj kvietigan odoron.
Ĝiaj maldikaj kaj longaj ovalaj folioj enhavas diafanajn punktojn, nomitaj "gasaj poŝoj", kiuj estas klare viditaj kiam oni metas la folion al la lumo.Ĝiaj orflavaj floroj montras kvin petalojn kaj multnombrajn stamenojn. Ili havas sekreciajn glandojn kiuj ruĝe koloras la fingrojn kiam oni ĉifas ilin. Ili floras supre de branĉetoj, de la malfrua printempo al frua somero. La frukto estas kapsulo kiu enhavas etajn semojn.
Hiperiko trapunkta estas planto kiu eltenas la varmegon kaj malvarmon ĝis -15 gradoj. Ĝi prosperas en leĝeraj grundoj, malriĉaj kaj en plena suno. Ni devas semi ĝin printempe, ĉar la semoj bezonas bonan lumon por ĝermi. Tiu planto resemiĝas aŭtune. Ĝiaj aeraj partoj malaperas vintre sed printempe ili rekreskas el la radiko. Tradicie, oni rikoltas hiperikon la 24-an de junio je tagmezo. Fakte, oni povas rikolti ĝin ekde ĝia florado. Tranĉante la planton je 20 cm de la pinto, oni sekigas ĝin por fari infuzaĵojn aŭ tinkturojn. Ĝi devas konservi ĝian koloron kaj aromon.
En popola medicino oni opinias, ke:
La ago de la hiperiko trapunkta estas sentata post 15 tagoj de kuracado. La traktado daŭras dum tri monatoj kaj ne devus esti haltigita subite.
Hiperiko trapunkta estas fotosentiviga, do ni devus eviti elmetadon al la suno dum oni uzas tiun planton. En interna uzo, hiperiko trapunkta havas interagojn kun multaj medikamentoj (perbuŝaj kontraŭkoncipiloj, kontraŭdeprimiloj, kontraŭkoaguliloj ...). En kazo de kuracado, serĉu konsilon de via kuracisto aŭ apotekisto.
Trapunkta hiperiko aŭ sankt-johana herbo (Hypericum perforatum) estas kuracplanto, kiun laŭtradicie oni elŝiru dum la nokto de sankta-Johano festo, je la somera solstico.
Sur la rando de la vojetoj, en senkulturejoj, hiperiko trapunktata leviĝas ĝis 60 centimetroj de alteco. Plurjara planto kun rigida kaj branĉplena tigo, ĝi eligas varman kaj kvietigan odoron.
Ĝiaj maldikaj kaj longaj ovalaj folioj enhavas diafanajn punktojn, nomitaj "gasaj poŝoj", kiuj estas klare viditaj kiam oni metas la folion al la lumo.Ĝiaj orflavaj floroj montras kvin petalojn kaj multnombrajn stamenojn. Ili havas sekreciajn glandojn kiuj ruĝe koloras la fingrojn kiam oni ĉifas ilin. Ili floras supre de branĉetoj, de la malfrua printempo al frua somero. La frukto estas kapsulo kiu enhavas etajn semojn.
Hypericum perforatum, también conocida como hipérico, hipericón, corazoncillo o hierba de San Juan, es la especie más abundante de la familia de las hipericáceas (Hypericaceae).
Es una planta común en los terrenos de baja y media altura. Se encuentra prácticamente en toda Europa, hasta el este de Rusia, y se ha aclimatado en numerosas partes del mundo: China, Australia, Norte de África y América.
Hipócrates la recomendó como remedio refrescante y antiinflamatorio.
Dioscórides escribe lo siguiente (con la ortografía de las traducciones antiguas): El Hyperico, llamado Androsemo por unos, por otros Corio, y por otros Camepytis, que quiere decir Pinillo, porque su resina huele a resina de pino, es una mata ramosa, roxeta y de un palmo de alta, que produce las hojas como la ruda, y de flor amarilla: la qual frotada entre los dedos, resuda un liquor semejante a la sangre, de donde vino a llamarse Androsemo que significa sangre humana. Nace el hyperico en lugares cultivados y ásperos. Tiene facultad de mover la orina y, aplicado por baxo, provoca el menstruo. Bebido con vino, extermina las tertianas y las quartanas. Su simiente bevida por una quarentena de días, cura la sciática y las hojas con la simiente aplicadas en forma de emplastro, sanan las quemaduras del fuego[1]
Es una hierba originaria de Europa, que se ha naturalizado en América y Australia. Los pétalos de la flor son de color amarillo dorado, con pequeñas motas negras en sus bordes, el apelativo latino perforatum proviene de las pequeñas perforaciones -en realidad son bolsas de aceite esencial- que pueden verse al trasluz en cada una de las hojas de esta planta. Son el doble de largos que los sépalos. Una peculiaridad de esta hierba es que, al aplastar entre los dedos alguna de sus hojitas, deja una mancha en la piel, su savia anaranjada.
En Australia y en los Estados Unidos se la considera como una maleza o una especie invasora y se la combate por medio de controles biológicos tales como los escarabajos del género Chrysolina, que se especializan en esta planta.[2][3]
Hypericum perforatum es una planta medicinal con múltiples aplicaciones. Por ejemplo, su aplicación tópica sirve para acelerar la cicatrización de las heridas.
Sin embargo, las propiedades de esta hierba que más han atraído a los investigadores se vinculan con su uso tradicional para el tratamiento de la depresión leve a moderada y la ansiedad.[4] Esta indicación ha sido validada en las últimas décadas por las agencias de salud de algunos países como Alemania, donde ha sido incluida en la farmacopea oficial, y se prescribe ampliamente con ese propósito terapéutico.[5]
Cuando el hipérico se utiliza como medicamento fitoterapéutico, generalmente se administra en forma de extractos estandarizados, con concentraciones fijas de los principios activos a los cuales se atribuyen los efectos farmacológicos; se estima que el más importante de estos es la hipericina, aunque estudios recientes reportan una mayor actividad de la hiperforina.[6][7] Esta conclusión se basa fundamentalmente en un ensayo con resultado negativo llevado a cabo por el Centro Nacional de Medicina Complementaria y Alternativa de los Estados Unidos.[8][9][10][11]
Para este fin (tratamiento de la depresión), la hierba de San Juan puede conseguirse en diversas presentaciones: como hierba, como gragea o cápsula, en bolsas de té o en tinturas.
El hipérico es un potente inductor enzimático del citocromo P450 (isoenzima CYP3A4) y posiblemente también de la glucoproteína P. Puede producir interacciones con otras sustancias, tales como la digoxina o anticoagulantes orales.[12]
Asimismo, se han documentado casos de rechazo de trasplante de corazón en dos pacientes que combinaron el tratamiento inmunosupresor (ciclosporina) y la toma de hipérico. En ambos casos, todo parece indicar que el hipérico provocó un descenso de las concentraciones plasmáticas de ciclosporina por debajo del nivel terapéutico, lo que causó el rechazo del injerto. Un estudio formal posterior demostró que el hipérico reduce la concentración plasmática de indinavir.[12]
Debido a la importancia de estos datos, parece prudente no asociar la toma de hipérico con la de ningún fármaco de metabolismo hepático.[12] Véase el apartado Tabla de interacciones con diversas sustancias. No se recomienda beber licor como el whisky
Hypericum perforatum puede interferir con la absorción de hierro y otros minerales. El responsable de la toxicidad de esta planta, es la hipericina, se trata de un pigmento heliantrono de color rojo encarnado y fluorescente que se encuentra en las manchas negras dispersas en la superficie de las hojas y pétalos florales del vegetal. Este compuesto se encuentra presente en la planta en todo momento y persiste cuando se seca o es henificada.[13]
La hipericina es la responsable de la foto toxicidad. Desde la antigüedad, se han observado trastornos de la piel en animales que habían comido de esta planta. Sólo en casos graves por sobrealimentación, se observaron convulsiones, crisis hemolíticas o muerte del animal. Como consecuencia de la fotosensibilización también se observan trastornos hepáticos e ictericia, al tiempo que las partes poco pigmentadas de la piel pueden necrosarse o desprenderse, dando lugar a cicatrices de curación muy lenta. Por otra parte, los animales hembras que comen de esta planta han mostrado una menor secreción láctea. En personas que hayan tomado esta planta y que se expongan al sol posteriormente, se puede presentar una pigmentación discreta de la piel (eritemas) o prurito.[14]
Hypericum perforatum ha demostrado ser solo ligeramente tóxico tras una única dosis oral o intraperitoneal. A nivel experimental, la DL50 han sido las siguientes:
La administración oral repetida del extracto de Hypericum perforatum a dosis de 300, 900 y 2700 mg/kg de peso corporal diarios en ratas y perros durante un período de 26 semanas no provocó cambios específicos de la sustancia. A dosis superiores a 900 mg/kg peso corporal diarios se desarrollaron signos inespecíficos de intoxicación: peso reducido, ligeros cambios en el hemograma, cambios en la química clínica y morfológicos los cuales, causados por la alta dosis, indicaron un daño leve, por sobrecarga, en el hígado y riñones.
Los estudios se llevaron a cabo con ratas y conejos y no hubo evidencia ninguna de cambios teratogénicos hasta dosis situadas en el rango de la toxicidad materna. Los efectos embrio-fetotóxicos, aparecieron a dosis tóxicas para la madre y se observó:
En el estudio de fertilidad con ratas, no se mostraron efectos sobre las mismas. Cabe destacar que, en las ratas, la hipericina se acumula en la leche pudiendo llegar a alcanzar concentraciones superiores a las del plasma materno, pero debido al amplio margen de seguridad que muestra la hipericina es improbable que la cantidad ingerida con la leche represente peligro alguno para el niño aunque no se dispone de información suficiente en lo relativo a la lactancia. Como precaución general, no se debe emplear ni en el primer trimestre del embarazo ni durante la lactancia.
Se han llevado a cabo estudios de mutagenicidad in vitro e in vivo concluyendo la inexistencia de riesgo mutagénico para el hombre con extracto de Hypericum.
Sobre el potencial carcinogénico no se tienen suficientes datos como para concluir la existencia o no de potencial[15]
La fotosensibilidad es el principal riesgo de toxicidad, siendo de tipo primaria puesto que se produce por absorción digestiva de la planta, pero en raras ocasiones pueden aparecer trastornos gastrointestinales, cansancio o intranquilidad[16]
Como se ha dicho previamente, la hipericina es el causante de la fotosensibilización (un tipo de reacción alérgica) en el ganado ovino provocando un exantema o la enfermedad conocida como St. Johnswort. Estos pigmentos de la planta, son ingeridos en ocasiones de manera abundante por los ovinos en pastoreo. Posteriormente llegan a la piel desde el torrente circulatorio donde oxidan los aminoácidos, histidina, triptófano y tirosina, modificando así la estructura y permeabilidad de las células. La gravedad va a depender de la dosis, de la duración de la ingesta así como de la intensidad de la radiación solar.
La clínica aparece en zonas no pigmentadas ni revestidas de lana, es decir, en cabeza, orejas, extremidades y mama donde aparecen inflamaciones, sobre todo en la cabeza recibiendo el nombre de “cabeza hinchada”, y en las zonas de la piel, ésta, estará hinchada, caliente y edematosa; esta patología, se continua con la exudación de un líquido seroso y desprendimiento del epitelio. Como mecanismo de defensa, los animales tratan de encontrar la sombra. En etapas posteriores, pueden necrosarse partes de la piel afectada así como las puntas de las orejas.
En ocasiones, aunque no es tan frecuente, puede aparecer:
Destacar que las intoxicaciones por Hypericum se producen, fundamentalmente, en animales ovinos durante la ingesta del pasto. Suelen ser los animales jóvenes los más afectados, debido a la competencia por el alimento en el pasto así como la falta de experiencia de estos últimos a la hora de elegir los alimentos no tóxicos.
Las intoxicaciones infantiles por Hypericum, según el Servicio de Información Toxicológica, se producen ocasionalmente, dado que estos pueden llevarse a la boca los fitofármacos que contengan el extracto de Hypericum que toman sus familiares adultos o alguien que lo necesite[18]
La Agencia Española del Medicamento considera necesario advertir que los productos que incluyen en su composición al Hypericum perforatum, tienen la capacidad de interaccionar con distintos medicamentos. Las interacciones son producto de la capacidad inductora del Hypericum perforatum sobre ciertas isoenzimas del citocromo hepático P450. Como consecuencia puede aparecer una disminución de las concentraciones plasmáticas y una pérdida del efecto terapéutico; teniendo en cuenta este mecanismo de la interacción, al dejar de administrar Hypericum perforatum puede también provocar un aumento de los niveles sanguíneos de algunos medicamentos con la consiguiente aparición de toxicidad, siendo especialmente importante en medicamentos de estrecho margen terapéutico. La interacción con los IMAO es de especial importancia debido a que conduce a una situación peligrosa porque puede dar lugar a crisis hipertensivas. Ocurre lo mismo en el caso de una ingestión de alimentos ricos en tiramina por la ingestión de esta planta.
Un ejemplo concreto es la interacción con los inhibidores de la proteasa en los cuales se produce una disminución significativa de las concentraciones plasmáticas de los mismos por la inducción de la isoenzima 3A4 del citocromo P450. Como resultado de ello, no se alcanzan concentraciones plasmáticas terapéuticas de este tipo de fármaco pudiendo desarrollarse resistencias y falta de eficacia del tratamiento.
La administración de los extractos de esta hierba es motivo de debate. Aunque existe evidencia limitada que sugiere su eficacia y seguridad, no ha sido evaluada sistemáticamente en lo que respecta a la incidencia de efectos secundarios e interacciones con otras drogas, con los riesgos que esto conlleva. Aun así, se menciona que, en el caso de algunos tratamientos, reduce su efecto como en los tratamientos para personas con VIH.
Se la considera un agente primario de la fotosensibilización en bovinos, en los cuales la hipericina se acumula en el tejido subcutáneo y reacciona con la luz solar, y provoca cuadros de inflamación de la dermis, especialmente de las partes menos pigmentadas, las cuales pueden desprenderse del animal.
Esta especie se conoce con numerosos nombres comunes en español: amnica, cientoenrama, corazón de ciervo, corazoncillo, corión, espantadiablos, hierba del agua, hierba de la sangre, hierba de las heridas, hierba de las machacauras, hierba de San Juan, hierba militar, hipericón, hipericón oficinal, hipérico, hipérico horadado, hipérico común, perforada, perforata, pericó, pericón, pericón amarillo, pericón común, pericón silvestre, perico, pericote, periquito, San Juan, sanjuanera, sanjuanes, san juanes, sanjuanines, té borde, trescalar, tresflorina, yerba de San Juan, yerbuca de San Juan.[19]
Hypericum perforatum fue descrita por Carlos Linneo y publicado en Species Plantarum 2: 785. 1753.[20]
Hipérico: nombre genérico que deriva del griego ὑπερικόν hyperikón. Su nombre está compuesto de ὑπ- "debajo" y ἐρείκη "Erica arborea" o "brezo blanco",[21] y por tanto significa "brezo bajo". La planta es mencionada 143 veces por los médicos grecolatinos.[22] Es fantasioso afirmar que procede del griego ὑπέρ "por encima" y εἰκών "imagen", queriendo decir "por encima de todo lo imaginable".[23]
perforatum: epíteto que se debe a las glándulas de aceite situadas en sus hojas y sépalos que le dan a la planta un aspecto perforado, si se observa al trasluz.[1]
Hypericum perforatum ha sido designado a lo largo de la historia con distintos nombres científicos, considerados sinónimos:
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|título= (ayuda) |url= (ayuda) |título= (ayuda) |título= (ayuda) |título= (ayuda) |título= (ayuda) Hypericum perforatum, también conocida como hipérico, hipericón, corazoncillo o hierba de San Juan, es la especie más abundante de la familia de las hipericáceas (Hypericaceae).
Liht-naistepuna (Hypericum perforatum) on naistepunaliste sugukonda naistepuna perekonda kuuluv mitmeaastane rohttaim.
Inglise keeles on liht-naistepuna tuntud kui St John's wort, mille eestikeelne vaste võiks olla 'jaanilill'. Rahvapärane nimetus tuleb sellest, et traditsiooniliselt korjati õitsevat liht-naistepuna jaanipäeval (24. juuni). Rahvasuus on taime nimetused emasterohi, jaanirohi, jeesuverelill, mariarohi, ninnilill, olangas, punalill, vereselitusrohi, viinalill ja viinapuna[1].
Liht-naistepuna on laialdaselt tuntud ravimtaimena, mida kasutatakse depressiooni raviks.
Liht-naistepuna vars on 20–90 cm kõrgune. Vars on alusel ümmargune, kõrgemal kahe servikuga (pikikandiga), säsikas. Vars on enamasti alusel lihtne, ülemises osas oksine, paljas. Mitmeaastasel risoomil võib sagedasti olla mitu püstist vart. Lehed vastakud, umbes 12 mm pikad, vastu valgust vaadates näha läbipaistvad näärmetäpid (eeterliku õli näärmed). Õite läbimõõt võib olla kuni 2,5 cm. Õied on viie teravatipulise kuldkollase kroonlehega, kroonlehtede välisserval on selgelt näha hõredad mustad näärmetäpid. Nõelatorkeid meenutavad näärmed on andnud aluse ladinakeelseks liigiepiteediks perforatum. Tupplehti on samuti 5, need on teravatipulised ning enamasti kolme rooga, õitsemise ajal sigimikust umbes 2 korda pikemad[2]. Õies on hulk tolmukaid, mis ühinevad alusel kolmeks kimbuks. Tolmukate keskel on kolme suudmega sigimik.[1]
Vili on piklik, munajas või kooniline kupar, milles on suur hulk seemneid. Taime levib puist- ja loomleviga, aga ka sipelgleviga. Seemned on pisikesed, pikliku kujuga ning tiivulised. Seemneid on palju. Sipelgate jaoks on seemnetel söödav lisand.[3]
Õitseb juunist septembrini.
Liht-naistepuna kasvab Euroopas, Siberis, Kesk-Aasias.[4] Sissetoodud liigina esineb ka Põhja- ja Lõuna-Ameerikas, Indias, Uus-Meremaal, Austraalias ning Lõuna-Aafrikas. Eestis on üsna levinud. Armeenias on taime looduslikud kasvukohad Sjunikhi, Vajotsh Dzori, Lori, Aragatsotni, Tavuši ja Gegharkhunikhi maakonnas.[5]
Liht-naistepuna kasvab sageli liivasel või kivisel pinnasel, eelistab valgusküllaseid kohti.[3] Kasvab jäätmaal, söötidel, kuivadel niitudel[6], puisniitudel, kinkudel, tee- ja põlluservadel,[7] kuivades võsades, metsaservadel, tarade ääres, kraavikallastel, loodudel[2].
Pikemalt artiklis Liht-naistepuna ürt
Lisaks ilusale väljanägemisele on liht-naistepuna hea ravimtaim ja droog.
Liht-naistepuna (Hypericum perforatum) on naistepunaliste sugukonda naistepuna perekonda kuuluv mitmeaastane rohttaim.
Inglise keeles on liht-naistepuna tuntud kui St John's wort, mille eestikeelne vaste võiks olla 'jaanilill'. Rahvapärane nimetus tuleb sellest, et traditsiooniliselt korjati õitsevat liht-naistepuna jaanipäeval (24. juuni). Rahvasuus on taime nimetused emasterohi, jaanirohi, jeesuverelill, mariarohi, ninnilill, olangas, punalill, vereselitusrohi, viinalill ja viinapuna.
Liht-naistepuna on laialdaselt tuntud ravimtaimena, mida kasutatakse depressiooni raviks.
Santio belarra edo milazuloa (Hypericum perforatum) Hiperikazeoen familiako belar landare zuzen adartsua da, 30-90 cm luzea, sortako lore horiak eta elkarren aurka antolatutako hosto txiki luzaranak dituena. Asiki-belarra izenaz ere ezagutzen da. Oso iparraldeko uharteetan izan ezik Europako beste lurralde guztietan hazten da, tontor eguzkitsuetan, sasi artean eta basoetako argi guneetan batez ere. Santio egunez baserrietako ate alboetan jarri izan da Euskal Herriko zenbait eskualdetan.[1]
Hiperforina duenez[2], sendabelar ezaguna da, ezaugarri antidepresibo, bakterio-kontrako eta antioxidatzaileak dituena.
Artikulu hau biologiari buruzko zirriborroa da. Wikipedia lagun dezakezu edukia osatuz. Santio belarra edo milazuloa (Hypericum perforatum) Hiperikazeoen familiako belar landare zuzen adartsua da, 30-90 cm luzea, sortako lore horiak eta elkarren aurka antolatutako hosto txiki luzaranak dituena. Asiki-belarra izenaz ere ezagutzen da. Oso iparraldeko uharteetan izan ezik Europako beste lurralde guztietan hazten da, tontor eguzkitsuetan, sasi artean eta basoetako argi guneetan batez ere. Santio egunez baserrietako ate alboetan jarri izan da Euskal Herriko zenbait eskualdetan.
Hiperforina duenez, sendabelar ezaguna da, ezaugarri antidepresibo, bakterio-kontrako eta antioxidatzaileak dituena.
Mäkikuisma (Hypericum perforatum) on monivuotinen, 30–70 senttimetriä korkea ruoho, jolla on keltaiset terälehdet. Mäkikuismaa kasvaa luonnonvaraisena myös Etelä-Suomen kedoilla.
Mäkikuismaa ja siitä tehtyjä valmisteita käytetään sisäisesti muun muassa depressiivisen alakuloisuuden, unihäiriöiden sekä tuska- ja jännitystilojen hoitoon. Mäkikuismalla on huomattavilla potilasmäärillä tehdyissä kliinisissä tutkimuksissa havaittu olevan masennustiloja ehkäisevä, tuskaa lievittävä ja rauhoittava vaikutus.[1][2] Rohtona käytetään mäkikuisman kukkivia versoja, joissa vaikuttavina aineina ovat hyperisiini eli punainen väriaine (0,1–0,3 %), flavonoidit (mm. hyperosidi ja rutiini), hyperforiini, katekiinityyppiset parkkiaineet, fytosterolit, fenolikarbonihapot ja eteerinen öljy (0,05–0,2 %).
Mäkikuisman on todettu olevan lievän ja keskivaikean depression masennuksen hoidossa tehokkaampi kuin lumelääke ja yhtä tehokas kuin pienet annokset trisyklisiä masennuslääkkeitä. Sillä voi olla myös hankalia yhteisvaikutuksia muiden lääkeaineiden kanssa.[3] Saksassa mäkikuisma on lääkäreiden yleisimmin määräämä luontaistuote masennuksen hoitoon.[4]
Mäkikuismalla voi olla yhteisvaikutuksia useiden lääkkeiden kanssa, sillä se laskee muiden lääkkeiden hoidollisia pitoisuuksia maksainduktion kautta ja voi näin heikentää esimerkiksi ehkäisypillereiden, immunosuppressiivien ja HIV-lääkkeiden tehoa. Yhteisvaikutuksia eri lääkeaineiden kanssa ei ole tutkittu laajemmissa tutkimuksissa, vaikka mäkikuisma onkin vuosisatoja tunnettu rohto. Yleisen suosituksen mukaan mäkikuismaa tulee nauttia vain, jos muita säännöllisiä lääkityksiä ei ole. Mäkikuisma ei yleensä vaikuta ajokykyyn. Sivuvaikutuksina on havaittu huimausta, väsymystä ja suun kuivumista noin 4–8 prosentilla, levottomuutta, päänsärkyä ja unettomuutta 1–2 prosentilla. Harvoissa tapauksissa voi esiintyä lieviä mahavaivoja, kun taas herkkäihoisilla saattaa esiintyä herkistymistä valolle. Mikäli muita haittavaikutuksia ilmenee tai tuotetta otetaan yliannostus, tulee ottaa yhteys lääkäriin.[5]
Mäkikuisma (Hypericum perforatum) on monivuotinen, 30–70 senttimetriä korkea ruoho, jolla on keltaiset terälehdet. Mäkikuismaa kasvaa luonnonvaraisena myös Etelä-Suomen kedoilla.
Hypericum perforatum
Le Millepertuis perforé, Millepertuis commun ou Millepertuis officinal (Hypericum perforatum L.) est une plante herbacée vivace de la famille des Clusiacées selon la classification classique (ou des Hypéricacées selon la classification phylogénétique).
Les poches sécrétrices transparentes présentes sur le limbe des feuilles allongées donnent l'impression de multiples perforations, particularité à l'origine du nom de millepertuis qui signifie mille trous.
Parmi toutes les espèces de millepertuis formant le genre Hypericum, l'appellation sans épithète de millepertuis désigne généralement le Millepertuis perforé.
Utilisée en médecine et largement popularisée pour ses effets antidépresseurs, la plante porte de nombreux surnoms dont le plus célèbre est celui d'herbe de la Saint-Jean.
Plante vivace de 25 à 100 cm, elle est dotée d'une tige souterraine ligneuse et d'une tige dressée avec deux côtes saillantes bien marquées. Ses feuilles sessiles, elliptiques ou linéaires, obtuses, plus claires à la face inférieure, ont un limbe ponctué de glandes translucides à huile essentielle, et bordé de points noirs correspondant à des glandes à hypéricine (en), principe actif à l'origine de ses propriétés. Les larges panicules de grandes fleurs jaune vif (2-3,5 cm) apparaissent entre mai et septembre. Ces fleurs ont cinq sépales et cinq pétales également ponctués de noir. Les verticilles staminaux sont formés de trois faisceaux d'étamines. Les fruits sont des capsules ovales bien plus longues que le calice[3].
Autrefois, Hypericum perforatum était considérée comme une plante magique associée à la magie blanche. Le millepertuis perforé est un très ancien chasse diable, c'est-à-dire qu'il faisait fuir les esprits tourmenteurs. C'est devenu le phytomédicament le plus prescrit contre la dépression nerveuse.
L'usage médicinal du millepertuis perforé remonte à au moins 2 400 ans, date où Dioscoride le préconisait dans ses ordonnances.
Réputé au Moyen Âge pour éloigner la mélancolie, le millepertuis avait aussi pour nom « herbe de Saint-Jean » (St John's wort en anglais) ou « chasse-diable », et il n'était pas rare de trouver accrochés un bouquet aux portes des granges[4].
Inscrit à la pharmacopée française en 1818, il tomba dans l'oubli à la fin du XIXe siècle. La pharmacologie moderne redécouvre certaines de ses propriétés thérapeutiques. Il est actuellement importé, en tant que remède, des pays d’Europe de l’Est et du Sud-Est (Bosnie, Bulgarie, Pologne, Roumanie, Ukraine…).[réf. souhaitée]
Il s'agit d'une plante sauvage héliophile et calcicole. Les bords des chemins, les lisières de forêt, prairies et talus secs, clairsemés et calcaires constituent ses habitats préférés. Le millepertuis craint l'ombre et l'humidité.
On le trouve dans toute l’Europe, en Asie, en Afrique du Nord et en Amérique du Nord.
L'espèce n'est pas encore évaluée à l'échelle mondiale et européenne par l'UICN. En France elle est classée comme non préoccupante [5]. Elle est considérée vulnérable (VU) en Provence-Alpes-Côte d'Azur.
Les sommités fleuries, cueillies au début de la floraison et séchées. Les fleurs doivent contenir 60 à 70 % de capsules immatures.[réf. nécessaire]
Le millepertuis contient une huile essentielle qui est extraite par hydrodistillation des sommités fleuries ou par macération dans une autre huile pour former l'huile de millepertuis, appelée aussi huile de cantarion. C'est une préparation pharmaceutique utilisée depuis l'Antiquité pour ses propriétés anti-traumatiques, hémostatiques, cicatrisantes et anti-inflammatoire non stéroïdien.[réf. nécessaire]
On attribue à la plante des propriétés vulnéraires : c'est un émollient et un adoucissant pour la peau (en usage externe et immédiat). La plante entière, les fleurs ou les feuilles sont utilisées en traitement cutané pour leurs vertus apaisantes, mais elles peuvent provoquer des réactions de photosensibilisation.
Les fleurs de millepertuis servent, par macération dans l’huile, à la préparation de l’huile de millepertuis, une huile rouge qui est renommée pour le traitement des brûlures et des contusions.[réf. nécessaire] Elle ne doit pas être employée pendant l'exposition solaire pour les raisons indiquées ci-dessus, mais comme après-soleil.
L'analyse indépendante la plus récente, menée par le groupe Cochrane, a couvert 29 essais cliniques et plus de 5000 patients. Le millepertuis est d'une efficacité comparable aux ISRS, les antidépresseurs conventionnels[6], dans la dépression majeure. Sa tolérabilité est supérieure, puisqu'elle est comparable à celle d'un placebo[7] soit, d'après le groupe Cochrane, des taux d'effets indésirables équivalents à la moitié et au cinquième des taux pour les ISRS et les tricycliques (exemple : imipramine), respectivement.
Les études sur le millepertuis dans les dépressions légères et modérées indiquent également une efficacité comparable à celle des antidépresseurs agissant sur la recapture de la sérotonine (ISRS)[8].
Les effets antidépresseurs du millepertuis sont dus principalement à l'hyperforine[9] (en usage interne et au long cours). Mais beaucoup des composants du millepertuis ont un effet inhibiteur sur les récepteurs du système nerveux central donc une action synergique est probable.[10]
Il est aujourd'hui autorisé à la vente en tant que médicament, comme en Allemagne depuis 1984, car de nombreuses études cliniques ont prouvé son efficacité. La dernière étude, publiée en 2005, montre que le millepertuis est aussi efficace sur la durée que l'antidépresseur de référence (l’Imipramine), mieux toléré et avec moins de risques de rechute.
Il est également assez communément utilisé dans les troubles déficitaires de l'attention de l'enfant, du moins aux États-Unis[11] avec, cependant, un effet contesté[12]. Dans cette étude, l'extrait de millepertuis utilisé contenait à l'origine 0,3 % d'hypéricine mais les chercheurs l'ont laissé se dégrader jusqu'à ce qu'il ne contienne que 0,13 % d'hypéricine et 0,14 % d'hyperforine. Comme les concentrations d'hyperforine n'ont pas été établies au début de l'étude et les concentrations d'hyperforine et d'hypéricine étaient bien inférieures à celles utilisées dans d'autres études, il est difficile de tirer quelque conclusion que ce soit.
De plus, le réputé chercheur de la Harvard Medical School, le Dr Joseph Biederman, coauteur de l'étude contestant l'efficacité du millepertuis dans le trouble déficitaire de l'attention, a suscité la controverse quand le sénateur Charles E. Grassley a révélé d'importants conflits d'intérêts avec l'industrie pharmaceutique. En guise d'exemple, le New York Times relate que le Dr Biederman avait déclaré à Harvard n'avoir rien reçu de Johnson & Johnson en 2001, puis, pressé de revoir cette déclaration, avait déclaré $3,500; Johnson & Johnson révéla au sénateur Grassley que la compagnie lui avait en fait accordé $58,169 cette année-là. Le Times montre que le médecin n'avait pas révélé non plus la somme qu'il avait reçue d'Eli Lilly pour étudier le Strattera dans les troubles déficitaires de l'attention, puisque la compagnie révéla qu'il avait reçu une somme en fait supérieure à ce qui est permis pour un chercheur de Harvard[13]. Peu avant l'intervention du sénateur Grassley, en 2007, le Dr Biederman était le second auteur en importance dans le domaine de la psychiatrie[14] et le premier dans le domaine des troubles déficitaires de l'attention[15], d'après l'ISI.
Le millepertuis est un inducteur du cytochrome p450[16], ce dernier étant un système enzymatique qui intervient dans le métabolisme de nombreux médicaments. Par ce biais, il peut diminuer ou augmenter l'efficacité de nombreux traitements.
Sans être comparables avec la gravité des effets indésirables des antidépresseurs médicamenteux[réf. nécessaire], de nombreuses interactions médicamenteuses sont répertoriées pour le millepertuis[17]. Déconseillé avec d'autres antidépresseurs (risque d'apparition d'un syndrome sérotoninergique), la plante est contre-indiquée pour certains médicaments métabolisés par l'une des principales isoenzymes des cytochromes P450 (CYP3A4). Ainsi, la plante est à proscrire en cas de traitements par :
Et elle est déconseillée en cas de traitements par : Digoxine, théophylline, phénytoïne, contraceptifs oraux (risque de grossesse).
Le millepertuis peut, chez certaines personnes, exacerber les émotions. Il peut également inhiber l'effet de médicaments comme la digoxine, la théophylline, les anticoagulants à base d'anti-vitamine K, des contraceptifs oraux et certains antidépresseurs, ou d'autres moins utilisés comme la ciclosporine, des traitements contre l'infection à VIH (sida) comme l'amprénavir ou l'indinavir, ou certains anticancéreux[18].
Pour expliquer son action sur l'humeur dans la dépression, on a fait l'hypothèse que le millepertuis agirait au niveau neuronal de façon analogue aux antidépresseurs médicamenteux en inhibant la recapture de certains composants, comme la dopamine, la sérotonine et la norépinéphrine[19].
Le millepertuis comporte un très grand nombre de composés actifs.[réf. nécessaire] Parmi les très nombreuses molécules actives identifiées (en fait des pigments), l'on retrouve principalement les groupes suivants : [réf. nécessaire]
Attention, ces composés d'un rouge intense ont des propriétés phototoxiques. Des bovins en ayant consommé jusqu’à 7 g (dose estimée) ont présenté des symptômes phototoxiques à type de bulles ou de brûlures, pouvant aller jusqu'à la mort.[réf. nécessaire] Mais les doses utilisées en médecine humaine sont 50 fois plus faibles, ce qui élimine, de principe, les complications phototoxiques.[réf. nécessaire] Cependant les patients absorbant plus de 100 mg de principe actif par jour, doivent éviter toute exposition solaire intense et/ou prolongée.[réf. nécessaire]
La recherche et l'analyse concernant l'ensemble de ces composés est actuellement en plein essor notamment en Europe et en Amérique du Nord. Mais trouver une nouvelle molécule en laboratoire, ne signifie pas trouver une nouvelle molécule active. Pour ce faire, des études cliniques portant sur de larges groupes de patients sont nécessaires. Le but étant évidemment pour l'ensemble des laboratoires, la recherche et la découverte d'une molécule originale, brevetable et donc exploitable commercialement. En fait, il semble qu'en 2005, nous en sommes face au millepertuis au stade où en était Bayer face à l'écorce de saule en 1865. Mais il est vrai que le produit apparaît beaucoup plus complexe, ceci malgré l'emploi de techniques innovantes et hautement performantes, comme la Chromatographie Liquide Haute Performance (CLHP), la BSM (Biologie supra-moléculaire), etc.
Hypericum perforatum
Le Millepertuis perforé, Millepertuis commun ou Millepertuis officinal (Hypericum perforatum L.) est une plante herbacée vivace de la famille des Clusiacées selon la classification classique (ou des Hypéricacées selon la classification phylogénétique).
Les poches sécrétrices transparentes présentes sur le limbe des feuilles allongées donnent l'impression de multiples perforations, particularité à l'origine du nom de millepertuis qui signifie mille trous.
Parmi toutes les espèces de millepertuis formant le genre Hypericum, l'appellation sans épithète de millepertuis désigne généralement le Millepertuis perforé.
Utilisée en médecine et largement popularisée pour ses effets antidépresseurs, la plante porte de nombreux surnoms dont le plus célèbre est celui d'herbe de la Saint-Jean.
Planda bliantiúil nó ilbhliantúil, uaireanta ina thom é Beathnua. Luibh Eoin Baiste a thugtar air freisin, agus luaitear le Colm Cille is Muire chomh maith é. Tá sé dúchasach ar fud na réigiún measartha is na sléibhte trópaiceacha. Na duilleoga breactha le faireoga, urchomhaireach nó bíseach, an-chaol nó ubhchruthach. Na bláthanna go minic mór feiceálach, buí le 5 pheiteal is an-chuid staimíní. Capsúl nó caor an toradh. An-chuid úsáidí aige mar luibh sa sean-am: cosaint ar asarlaíocht is oilc eile, agus luibh íce. Chuir Bord Leigheasra na hÉireann cosc ar a dhíol in Éirinn mar chógas leighis i 2001, mar gheall ar na drochiarmhairtí a fhéadfaidh a bheith aige, go mór mór nuair a bhíonn cógais eile leighis in úsáid ag duine ag an am céanna.
A abeloura[1], hipérico, ou herba de San Xoán (Hypericum perforatum), (en inglés, St. John's wort), é unha herbácea europea, a especie máis abundante da familia das gutíferas (Guttiferae) ou hipericáceas (Hypericaceae). Cómpre non confundila coa dedaleira, que tamén recibe o nome de abeloura. Abunda en Galiza, sendo unha das herbas empregadas na noite de San Xoán. Nalgúns vocábulos chámanlle artemixa, abelouro, abeluria, hiperico, milfurada, pericón, herba das feridas ou corazonciño.[2]
Outras especies levan o nome de herba de San Xoán (véxase: Herbas de San Xoán).
É unha planta común en terreos de baixa e media altura. Atópase practicamente en toda Europa, até o leste de Rusia. Aclimatouse en numerosas partes do mundo coma na China, Australia, Norte de África e as Américas.
O nome hipérico deriva do grego hyperikon ("sobre das imaxes" ou "por riba dunha aparición"). Para algúns, o nome fai referencia á propiedade que se lle atribuía de facer fuxir os espíritos e aparicións; por iso a xente acostumaba pendurar flores desta planta sobre as iconas relixiosas polo día de San Xoán, ademais de ser unha das herbas de San Xoán. Para outros, as glándulas dos seus pétalos semellan formar imaxes (a este feito déuselle moita importancia na Idade Media, xa que era utilizado nos exorcismos polas súas virtudes cabalísticas). O termo perforatum débese ás glándulas de óleo situadas nas súas follas e sépalos que lle dan á planta un aspecto furado, se se observa á luz reflectida.[3] O nome vulgar herba de San Xoán fai referencia a que, ademais de florear no mes de xuño, era unha das herbas de San Xoán. Marcial Valladares Núñez en 1884 no seu Diccionario gallego-castellano, fala de dúas especies que reciben este nome: Hypericum quadrangulum e Hypericum perforatum (véxase Herbas de San Xoán).
Hipócrates recomendouna coma remedio refrescante e antiinflamatorio.
Dioscórides escribe o seguinte: O Hiperico, chamado Androsemo por uns, por outros Corio, e por outros Camepytis, que quere dicir Piñeiriño, porque a súa resina cheira á resina do piñeiro, é unha mata ramallosa, arrubiada e dun palmo de alta, que produce unhas follas coma as da ruda, e de flor amaella: que esmagada entre os dedos, bota un zume semellante ao sangue que se chamou Androsemo que significa sangue humano. Nace o hipérico en lugares cultivados e ásperos. Ten facultade de mover os ouriños e, aplicado por baixo,provoca o menstro. Bebido con viño, extermina as tertianas e mailas cuartás. A súa semente bebida por unha corentena de días, cura a ciática e as follas coa semente aplicadas en forma de emplastro, sandan as queimaduras do lume[3]
En Galiza aparece nos primeiros dicionarios botánicos co nome de Herba de San Jôan: Juan Cuveiro Piñol no seu Diccionario Gallego, Barcelona, 1876 fala da planta. Tamén Marcial Valladares Núñez xa falaba dela en 1884 no seu Diccionario gallego-castellano, Santiago[4].
É un arbusto orixinario de Europa, que se ten naturalizado nas Américas. Os pétalos da flor son de cor amarela dourada, con pequenas tachas negras nos seus bordos, o apelativo latino perforatum provén dos buratiños -en realidade son saquetas de óleo esencial- que poden verse á luz reflectida en cada unha das follas desta planta.Son o dobre de longos ca os sépalos. Unha peculiaridade desta herba é que, ao esmagar entre os dedos algunha das súas follas, o zume alaranxado deixa unha mácula na pel. En Australia e nos Estados Unidos considérase má herba ou especie invasora e se combate por medio de controis biolóxicos tales como os escaravellos do xénero Chrysolina, que se especializan nesta planta.[5][6]
Hypericum perforatum é ademais unha planta medicinal con múltiples aplicacións. Por exemplo, a súa aplicación tópica serve para acelerar a cicatrización das feridas.
Porén, as propiedades desta herba que máis atraen aos investigadores vincúlase co uso tradicional para o tratamento da depresión leve a moderada.[7] Esta indicación foi validada nas últimas décadas polas axencias de saúde dalgúns países como Alemaña, onde se incluíu na farmacopea oficial, e prescríbese amplamente con ese propósito terapéutico.[8]
Cando a abeloura se emprega coma menciña fitoterapéutica, xeralmente se administra en forma de extractos estandarizados, con concentracións fixas dos principios activos aos cales se atribúen os efectos farmacolóxicos; estímase que o máis importante destes é a hipericina, aínda que estudos recentes reportan unha maior actividade da hiperforina.[9][10] Esta conclusión baséase fundamentalmente nun ensaio con resultado negativo levado a cabo polo Centro Nacional de Medicina Complementaria e Alternativa dos Estados Unidos.[11][12][13][14]
Para este fin (tratamento da depresión), a herba de San Xoán pode conseguirse en diversas presentacións: como herba, como graxea ou cápsula, en bolsas de té ou en tinturas.
A administración dos extractos desta herba é motivo de debate. Aínda que existe evidencia limitada que suxestiona a súa eficacia e seguranza, non ten sido avaliada sistematicamente respecto da incidencia de efectos secundarios e interaccións con outras drogas, cos riscos que isto comporta. Con todo, menciónase que, no caso dalgúns tratamentos, reduce o seu efecto coma nos tratamentos antirretrovirais para persoas con VIH.
Considérase un axente primario da fotosensibilización en bovinos, nos que a hipericina se acumula no tecido subcutáneo e reacciona coa luz solar, e provoca cadros de inflamación da derme, especialmente das partes menos pigmentadas, as que poden desprenderse do animal.
Como unha das herbas de San Xoán atribuíanselle propiedades medicinais e máxicas. Estaba considerada como unha planta especial contra o demo.
A herba de San Xoán limpa a cara de grans.
Hypericum perforatum designouse ao longo da historia con distintos nomes científicos, considerados sinónimos:
En inglés:
A abeloura, hipérico, ou herba de San Xoán (Hypericum perforatum), (en inglés, St. John's wort), é unha herbácea europea, a especie máis abundante da familia das gutíferas (Guttiferae) ou hipericáceas (Hypericaceae). Cómpre non confundila coa dedaleira, que tamén recibe o nome de abeloura. Abunda en Galiza, sendo unha das herbas empregadas na noite de San Xoán. Nalgúns vocábulos chámanlle artemixa, abelouro, abeluria, hiperico, milfurada, pericón, herba das feridas ou corazonciño.
Outras especies levan o nome de herba de San Xoán (véxase: Herbas de San Xoán).
Kantarion (gorač, rupičasta pljuskavica, kantarijon, Gospina trava, Bogorodična trava, gospino zelje, sentjanzovka, sentjanzevka) ili lat. Hypericum perforatum je višegodišnja zeljasta biljka iz istoimene porodice goračevke (kantarionovke; Hypericaceae).
Kantarion je višegodišnja zeljasta biljka s razgranatim korijenom. Stabljika je uspravna, gola, visine od 20 do 100 cm. Cvjetovi su žuti. Cvjeta od svibnja do rujna.
Biljka treba zemljišta srednje bogata hranjivim tvarima te umjereno topla i umjereno svijetla staništa.
Biljka sadrži hipericin, pseudohipericin, izohipericin (u cvatima), hiperozid, kvercetin, rutin, kvercitrin, biapigenin, amentoflavon, katehin, epikatehin, klorogensku kiselinu, hiperflorin, karotenoid, sterol, leukoantocijan i eterično ulje.Sadrži oko 55 mg % vitamina C te oko 55 mg % karotina, kao i do 10 % taninskih tvari.[1] Od makroelemenata u nadzemnim dijelovima su nađeni (mg/g) kalij (16,80), kalcij (7,30), magnezij (2,20) i željezo (0,11). Također prisutni su i mikroelementi (mkg/g): mangan (0,25), bakar (0,34), cink (0,71), kobalt (0,21), molibden (5,60), krom (0,01), aluminij (0,02), selen (5,00), nikl i stroncij (po 0,18 svaki), kadmij (7,20), olovo (0,08) i bor (40,40).[2]
Kantarion se rabi kao antidepresiv, sedativ i kao antibiotik. Može se rabiti i za vanjsku uporabu. Aktivna supstanca je hiperflorin. Ekstrakt kantariona povisuje koncentraciju neurotransmitera seratonina i noradrenalina na sinapsama. Kantarionovo ulje (Oleum hyperici) je naširoko poznato i koristi se za ublažavanje i liječenje opeklina. Dobija se maceracijom svježih cvjetova kantariona maslinovim uljem.
Antidepresivno djelovanje je poznavao već u srednjem vijeku Paracelsus, a školska medicina ga je 1970-ih godina potvrdila. Kaže se da kantarion koji cvjeta usred ljeta skuplja sunčeve zrake da bi ih ljudima dao za vrijeme tamnih mjeseci.
Može se koristiti i kao začin, posebno za jela od slatkovodne ribe.[3]
Potražnju za proizvodnju različitih proizvoda na temelju gospine trave nije moguće zadovoljiti samo kroz prikupljanje divljih biljaka. Zato se uzgajaju prikladne sorte u poljskim uvjetima. Kantarion je jedna od najvažnijih ljekovitih biljaka koja se uzgajaju u Njemačkoj. 1999. g. gospina trava je uzgajana na 630 hektara u Njemačkoj, u Austriji se uzgajala 1999. g. na do 240 hektara. Biljke se uzgajaju i u Rusiji,Poljskoj i Južnoj Americi.
Uzgaja se na neplodnom tlu. Sjeme se sije u proljeće ili jesen.
Hypericum perforatum
Hypericum perforatum
kantarionovo ulje
Wilfort, R. Ljekovito bilje i njegova upotreba, Zagreb 1974.
Kostina,L. Lečenije zveroboiem,Minsk 2005.
Dubrovin,I. Celitelnij zveroboi,Moskva 2017.
Kantarion (gorač, rupičasta pljuskavica, kantarijon, Gospina trava, Bogorodična trava, gospino zelje, sentjanzovka, sentjanzevka) ili lat. Hypericum perforatum je višegodišnja zeljasta biljka iz istoimene porodice goračevke (kantarionovke; Hypericaceae).
Dźěrkaty křižomnik (Hypericum perforatum) je rostlina ze swójby Křižomnikowych rostlinow (Hypericaceae). Dalše serbske mjena su janske zelo, dźěrkate janske zelo, dźěrkawe łopješko, twjerda trawa, swjatojanske zelo, lubozne zelo, konjaca krej a škerjedźiwe zelo.
Dźěrkaty křižomnik je trajne zelo, kotrež docpěwa wysokosć wot 30 hač 60 cm.
Stołpik je dwuhranity a sylnje rozhałuzowany.
Łopjena su transparenće dypkowane, přećiwostejne, sedźace, jejkojće-dołhojte a docpěwaja dołhosć wot 1 hač 2 cm.
Kćěje wot julija hač awgusta. Złotožołte kćenja su na kromje čornje dypkowane, pjećličbne, steja we wjelekćenowych pakićach a docpěwaja wulkosć wot 2 hač 2,5 cm. Keluškowe łopješka su lancetojte, wótre a docpěwaja dołhosć wot 4 hač 5 mm a su dlěše hač płodowy spódk. Krónowe łopješka su złotožołte a docpěwaja dołhosć wot 10 hač 15 mm.
Rostlina wobsahuje hypericin, flavonoidy, eteriske wolije a třěski .
Rosće na suchich łukach, trawnikach, holach, njewobdźěłanych rolach, kerčinowych a lěsnych kromach, skłoninach, železniskim šotrje, drjebiznowych městnach a pustych płoninach.
Rostlina w Europje rozšěrjena.
Dźěrkaty křižomnik (Hypericum perforatum) je rostlina ze swójby Křižomnikowych rostlinow (Hypericaceae). Dalše serbske mjena su janske zelo, dźěrkate janske zelo, dźěrkawe łopješko, twjerda trawa, swjatojanske zelo, lubozne zelo, konjaca krej a škerjedźiwe zelo.
Jóhannesarjurt (e. St. John's Wort) er fjölær jurt af ættkvíslinni Hypericum. Jurtin blómstrar í kringum hátíð Jóhannesar skírara (St. John) og er nafn plöntunnar dregið af því. Latneska heiti jurtarinnar er Hypericum perforatum, en Hypericum er komið frá grísku orðunum hyper, sem þýðir "fyrir ofan", og eikon, sem þýðir "mynd". Perforatum vísar til smárra olíukirtla á laufum plöntunnar, ef krómblaðið er kramið kemur dökkrauð olía úr þessum kirtlum.
Jóhannesarjurt vex villt víða um heim, þar með talið í Evrópu, Asíu og Norður Ameríku en hún vex best í ljósum, heitum og sönduðum jarðvegi. Jurtin hefur verið notuð í læknisfræðilegum tilgangi allt frá miðöldum við ýmsum kvillum en í dag er hún helst notuð við vægu þunglyndi.
Mikilvægt er að hafa í huga að þó að jóhannesarjurt sé náttúrulyf getur það milliverkað við önnur lyf og náttúruvörur. Ávallt skal ráðfæra sig við lækni eða annan heilbrigðisstarfsmann áður en byrjað er að nota jóhannesarjurt.
Jóhannesarjurt er jurt af ættkvíslinni Hypericum, hún þekkist einnig á Íslandi sem jónsmessurunni og doppugullrunni. Latneska heiti hennar er Hypericum perforatum. Jurtin hefur mikið verið notuð í meðferð í fjölmörgum hjátrúum og við taugaröskunum. Þeir hlutar plöntunnar sem eru notaðir í náttúru- og jurtalyf eru blómin og blöðin, blöðin eru þó notuð í minna mæli.[1]
Jóhannesarjurt er ein af elstu og best rannsökuðu lyfjajurtunum og á hún sér langa sögu um notkun í meðferð geðrænna vandamála. Hypericum kemur frá grísku orðunum hyper (fyrir ofan) og eikon (mynd) sem gefur til kynna notkun hennar á miðöldunum en þá var hún látin hanga fyrir ofan myndir af guðum til þess að halda eigandanum frá illum öflum. Nafnið á tegundinni, perforatum, vísar til smárra olíukirtla sem finnast á laufum plöntunnar sem sjást þegar laufunum er haldið að sólinni. Ef gult krónublaðið er kramið kemur dökkrauð olía úr þessum kirtlum. Enska og íslenska heiti hennar er svo dregið af því að jurtin blómstrar í kringum hátíð Jóhannesar skírara (St. John). Í kringum 1800 var jóhannesarjurt skilgreind sem meðferð við taugakvilla og hefur hún einnig verið notuð við þunglyndi en þegar þróun þunglyndislyfja fór af stað byrjuðu þýskir vísindamenn að leita að svipuðum eiginleikum í jóhannesarjurt. [2][3]
Miðað við langa sögu eru mörg mismunandi preparöt notuð. Gæði hráefnanna í plöntunni er grundvallaratriði þess að preparat innihaldi mikil og stöðug gæði. Utanaðkomandi áhrif, svo sem loftslag, aðstæður og tímasetning uppskeru og þurrkunar, leiða til mismunandi gæða hráefnisins. Af þeirri ástæðu blanda framleiðendur yfirleitt plöntuefnum saman frá góðum og slæmum uppsprettum, frá mismunandi stöðum og árum. Meiri hluti preparatanna sem notuð eru við þunglyndi eru þurrkaðir útdrættir sem hafa gengist undir flókið og mjög háþróað undirbúningsferli. Þurrkað plöntuefni er frekar unnið í olíur, fljótandi útdrætti eða te. [2] [3] Talað er um jóhannesarjurt í mónógrafíu German Commission E og í mörgum lyfjaskrám í sambandi við verkun þess gegn þunglyndi og veiruhamlandi eignleikum í mönnum. [4]
Gæðalýsingu er að finna í evrópsku lyfjaskránni (Ph. Eur.) og mónógrafíur er að finna hjá evrópsku lyfjamálastofnuninni (EMA).
Jóhannesarjurt er fjölær jurt með mörgum greinum og gulum blómum. Hún vex villt víða um heim, um mest alla Evrópu, Asíu, og Norður Ameríku. Gróðursetningartíminn er snemma vors þegar öll hætta á frosti er yfirstaðin. Best er að byrja á því að setja hana niður innandyra í heitu umhverfi með sól og setja hana svo aftur niður seint um vorið. Umpottun á sér stað þegar plönturnar eru um 5cm. Passa verður að hafa um 30cm á milli plantnanna þegar þær eru settar niður vegna þess að rætur þeirra breiða mikið úr sér. Það getur tekið fræin allt að þrjá mánuði að spíra. Hæð plöntunnar getur verið frá 1 feti (um 30,5cm) upp í 3 fet (um 91,5cm). [1]
Jurtin vex best í ljósum, heitum og sönduðum jarðvegi. Blóm plöntunnar geta vaxið ef jurtin er að hluta til í skugga en betra er fyrir blómin að vera í einhverri sól. Blómin blómstra seint í júlí og ágúst annað árið eftir fyrstu gróðursetningu. Uppskeran er þegar blómin eru í fullum blóma og þá er ⅓ af efri hluta plöntunnar skorinn. [3][1]
Jóhannesarjurt hefur verið notuð í læknisfræðilegum tilgangi allt frá miðöldum, en þá var plantan helst notuð vegna bólgueyðandi og græðandi eiginleika hennar. Jóhannesarjurt var einnig þekkt fyrir þvagræsandi eiginleika og sáragræðslu ásamt því að hafa áhrif á taugatengda verki eins og bakverki. Árið 1633 var plantan skráð sem smyrsli fyrir bruna og á þeim tíma var olían úr plöntunni einnig vinsæl. Rauðleitur ólívuolíu útdráttur sem búinn var til úr ferskum blómum plöntunnar var tekinn inn notaður til að meðhöndla kvíða og einnig borinn á útvortis sem bólgueyðandi, útvortis notkun var einnig talin vera mjög gagnleg við gyllinæð. Jóhannesarjurt féll í vannot en áhugi manna á plöntunni jókst síðar meir og er plantan nú í dag frumþáttur í fjölda preparata til meðhöndlunar á kvíða og þunglyndi.[5]
Alþýðunotkun (hefð fyrir notkun) jóhannesarjurtar er sú notkun sem fólk hefur notað plöntuna frá upphafi. Jóhannesarjurt hefur verið notuð til inntöku við eftirfarandi kvillum út frá hefð: Þunglyndi, vægt þunglyndi/depurð, kvíði, hjartsláttarónot, geðsveiflur tengdar tíðahvörfum, ofvirkni og athyglisbrest (ADHD), áráttu- og þráhyggjuröskun (OCD), skammdegisþunglyndi (SAD), vöðvaverkir, settaugabólga, svefnleysi, skjallblettir, lifrarbólgu C, þvagræsandi, meltingartruflanir, þreyta, til að hætta að reykja, vefjagigt/vöðvagigt, einkenni tíðarhvarfa, síþreyta (CFS), höfuðverkur, mígreni, taugapína, lystarleysi, krabbamein, HIV/alnæmi, þyngdartap, iðrabólga (IBS).
Fólk hefur notað plöntuna útvortis, sem olíukenndar efnablöndur til að meðhöndla: Marbletti, skordýrabit, bólgu, gyllinæð, taugapínu, vöðvaverki, 1.gráðu bruna, sáragræðslu og skjallbletti.
Einnig eru seyði gerð úr jóhannesarjurt sem innihalda ekki hypericin og hafa þau verið notuð við gerð áfengis.[6]
Evrópska lyfjastofnunin (EMA) hefur gefið út mónógrafíu um jóhannesarjurt. Þar koma fram ábendingar, þegar plantan var skráð hér á landi, bæði út frá hefðbundinni notkun jurtarinnar (e. traditional use) og ábendingar sem byggðar eru á vísindalegum grunni (e. well-established use). Þegar efni hefur verið notað í 30 ár eða meira, við ákveðinni ábendingu, getur það fengið skráningu sem náttúrulyf byggt á hefð.
Jóhannesarjurt kom á markað á Íslandi undir nafninu Modigen® í október árið 2000 og var til hér á landi um nokkurt skeið. Modigen er náttúrulyf og er til í hylkjum sem inniheldur 300mg af virka innihaldsefninu, staðlað innihald er 900mcg hypericin. Modigen hefur nú verið afskráð hér á landi en það er vegna þess að ekki hefur verið sótt um endurskráningu þegar leyfið rann út, það getur verið vegna þess að jóhannesarjurt milliverkar við fjölda lyfja og því nauðsynlegt að leita sér ráðgjafar hjá fagaðila áður en byrjað er á náttúrulyfinu. Jóhannesarjurt milliverkar einnig mikið við önnur lyf, t.d. eykur það virkni blóðþynnandi lyfja og dregur úr virkni getnaðarvarnartölfunnar.[7][8]
Innihaldsefni jóhannesarjurtar safnast aðallega saman í blómi plöntunnar. Yfir 150 innihaldsefni hafa fundist í plöntunni en þeim hefur verið skipt niður í nokkra flokka. Þeir efnaflokkar sem taldir eru hafa mesta virkni í jóhannesarjurt eru naptódíantrónar (e. naphthodianthrones), flavonóíðar og flóróglúkínólar (e. phloroglucinols). Bygging 30-50% efnanna hefur ekki verið skilgreind en talið er að sum þeirra stuðli að klínískum áhrifum.[2][9]
Eftirfarandi efnaflokka og efni má finna í jóhannesarjurt:
Auk þessara flokka má finna tannín, xantón, mettaðar fitusýrur, vítamín og fleira í plöntunni.[10][2]
Naptódíantrónar finnast í jóhannesarjurt í minni styrk en 0,1-0,15%. Antrakínón afleiður hypericins og pseudohypericins eru best þekktu hlutar plöntunnar. Ísóhypericin og protohypericin eru einnig til staðar. Magn hypericins í plöntunum er mismunandi eftir því hvar plantan vex og styrkur hypericins er háð plöntuhluta. Mesta magn hypericins má finna í blóminu, blómhnappinum, efstu laufunum og efri hluta stilksins. Hypericin er talið valda ljósnæmi sem er ein af aukaverkunum jóhannesarjurtar. [10][5][11]
Styrkur flavonóíða í jóhannesarjurt er undir 12% í blóminu og um það bil 7% í laufum og stilkum. Flavonóíðar innihalda meðal annars hyperosíða, rutin, kaempferol, quercetin og quercitrin svo eitthvað sé nefnt.[5]
Hyperforin og adhyperforin, sem tilheyra flokki flóróglúkínóla, finnast í plöntunni í styrknum 2-4%. Hyperforin er óstöðugt og getur orðið fyrir niðurbroti af völdum oxunar en í plöntunni er hyperforin verndað með andoxunareiginleikum flavonóíðanna.[5]
Hypericin og hyperforin eru tvö helstu virku efni jóhannesarjurtar. Hyperforin er talið vera mikilvægara í virkninni gegn þunglyndi heldur en hypericin. Droginn og alkahól útdráttur hans inniheldur um það bil 10 sinnum meira af hyperforin (2-4%) heldur en hypericin. Styrkur hypericins og pseudohypericins í droga fer eftir þroskastigi plöntunnar og getur hann verið milli 0,03-0,3%.[2][9]
Talið er að samlegðaráhrif gætu verið til staðar þar sem að hypericin var í upphafi talið vera mikilvægara í virkninni gegn þunglyndi heldur en hyperforin. Síðar hafa komið upp hugmyndir um að hyperforin væri virkara ásamt því að efnin væru jafn virk. Því virðist sem bæði efnin þurfi að vera til staðar til að fá fram verkunina. Flavonóíðarnir virðast einnig virka gegn þunglyndi en staðfest er að þeir virka með því að auka lyfjafræðilega eiginleika annarra innihaldsefna eins og hypericíns.[11][2]
Flestar rannsóknir sem gerðar hafa verið á jóhannesarjurt eru til þess gerðar að rannsaka virkni hennar gegn þunglyndi.
Klínískar rannsóknir hafa sýnt að jóhannesarjurt reynist vel við meðhöndlun á slæmu lundafari og svefnleysi en jurtin hefur margvísleg áhrif á miðtaugakerfið. Plantan getur því mögulega haft svipaða virkni og algeng þunglyndislyf. Þegar jóhannesarjurt hefur verið blandað saman við önnur náttúrulyf hefur sýnt sig í klíníkskum rannsóknum að það hjálpi við ýmsum geðrænum sjúkdómum eins og þunglyndi, kvíða og svefnleysi[12]
Virkni jóhannesarjurtar gegn þunglyndi var talin stafa af hyperforini, hypericini og pseudohypericini og nokkurra flavanóíða. Hlutverk og virkni þessara mismunandi efna er enn ekki þekkt að fullu.[13]
Mörg þunglyndislyf hindra endurupptöku mónóamína (noradrenalín, serótónín og dópamín) úr taugamótum í taugafrumu. Þessi lyf flokkast sem MAO hemlar, sértækir noradrenalín endurupptökuhemlar (NSRI) og sértækir serótónín endurupptökuhemlar (SSRI). In vitro rannsóknir gefa til kynna að aðal ástæða fyrir virkni Hypericum útdrátta við þunglyndi sé hindrun á MAO ensíminu. Þó að nokkrar rannsóknir hafi sýnt fram á að það finnist MAO hemlar í útdrætti jóhannesarjurtar þá er styrkur þeirra of lágur til að geta skýrt klíníska verkun jurtarinnar gegn geðdeyfð. Góðar upplýsingar hafa fengist úr in vitro rannsóknum um að Hypericum útdrættir, og þá sérstaklega hyperforín og adhyperforín, séu öflugir ósértækir hindrar á endurupptöku serótóníns, noradrenalíns og dópamíns úr taugamótum. Útdrættir sem innihalda ekki hyperforín geta líka hindrað endurupptökuna í litlu til meðal miklu magni og gæti það verið vegna fáliðuðu prócýanídanna. In vivo rannsóknir hafa sýnt fram á að Hypericum útdrættir leiði til fækkunar á beta adrenergum viðtökum og fjölgunar á serótónín viðtökum. Hypericum útdrættir hafa einnig sýnt fram á virkni í týpískum dýramódelum sem notuð eru til að kanna áhrif þunglyndislyfja.[2] Í langan tíma var haldið að hypericin væri aðal efnið í jóhannesarjurt sem virkaði gegn þunglyndi en nú er vitað að það hefur aðeins litla verkun gegn þunglyndi sem MAO hemill eitt og sér vegna þess að aðgengi þess er mjög lélegt. Ef hypercin var gefið með pólýfenól epicatechini, procýanídíni, hyperosíði eða rutíni, sem oftast finnst í útdrætti af jóhannesarjurt, jókst styrkur hypericins í plasma greinilega og fram komu mikil áhrif gegn þunglyndi í sundprófi sem gert var á músum.[14]
Jóhannesarjurt virðist einnig virka sem serótónín 5-HT3 og 5-HT4 viðtaka antagónisti og fækka beta adrenergum og serótónín 5-HT1 og 5-HT2 viðtökum þegar hún er notuð að staðaldri í dýrum. Þessi áhrif á taugaboðefnin virðast valda skammtaháðri kortisól örvun. Hyperforin hindrar einnig upptöku GABA og L-glútamats í taugamótum. Áhrif jóhannesarjurtar á serótónín kann að vera aðal ástæðan fyrir virkni gegn þunglyndi. Mörg innihaldsefni jóhannesarjurtar virðast þó hafa virkni gegn þunglyndi. Hypericin hindrar katekól-O-metýl transferasa (COMT) og mónóamín oxídasa (MAO) in vitro. Hins vegar nær hypericin ekki fullnægjandi styrk í vefjum manna til þess að ná fram þessum áhrifum. Hypericin hefur einnig sækni í sigma viðtaka og virkar eins og antagónisti á viðtaka adenósíns, bensódíazepína, GABA-2, GABA-B og inostiol trífosfats. Forklínískar rannsóknir hafa bent til þess að 50% etanól útdráttur af jóhannesarjurt gæti haft kvíðastillandi verkun. [6] Langtímarannsóknir á notkun jóhannesarjurtar hafa sýnt fram á að jurtin er nokkuð örugg. Helst hefur verið kvartað yfir meltingarónotum og húðútbrotum við notkun hennar.[15]
Eðlisefnafræðilegir eiginleikar plöntunnar valda óstöðugleika í vatni sem hugsanlega leiðir til lélegs aðgengis. Margar aðferðir hafa verið reyndar til þess að auka leysanleika ýmissa plöntuútdrátta, til dæmis kúrkúmíns, í vatni og má þar nefna fleytingar, koma efnunum fyrir í cýklódextríni og búa til fleytu með efnum á föstu formi. Áhrif formúleringar á eðlisefnafræðilega eiginleika, lyfjahvörf og verkun jóhannesarjurtar við sársauka hafa ekki verið skýrðar.[4]
Árið 2006 voru 40 preparöt af Hypericum vörum, á lista sem meðferð gegn þunglyndi í Þýskalandi og voru flest preparötin þurrkaðir útdrættir sem voru fáanlegir í hylkjum eða töflum. Dagskammtur útdráttanna var á breiðu bili, eða 80-1700mg, en í flestum tilfellum var skammturinn á milli 500 og 1200mg. Etanól (50-80%) var notað í útdráttinn í flestum tilfellunum og metanól í minnihluta.[2]
Dæmigerður skammtur af jóhannesarjurt er 300mg þrisvar á dag ef útdrátturinn er staðlaður í að innihalda 0,3% hypericin. Sumar vörur eru staðlaðar að hyperforin innihaldinu, þá yfirleitt 2-3%, og eru sömu skammtar fyrir þá útdrætti og þann sem er staðlaður að 0,3% hypericin. Tvær rannsóknir hafa sýnt fram á ávinning þegar þetta er tekið í einum 900mg skammti á dag. Enn annað tilbrigði af jóhannesarjurt hefur sýnt fram á árangur í tvíblindum rannsóknum, en það inniheldur lítið hyperforin og er gefið í 250mg skömmtum tvisvar á dag. Vísbendingar benda til þess að minni líkur séu á að þetta tilbrigði milliverki við önnur lyf. Ef jurtin fer illa í magann er gott að taka hana með mat og gott er að hafa í huga að það getur tekið 4 vikur að fá fram fullum áhrifum.[3]
Margar rannsóknir hafa ekki sýnt fram á alvarlegar aukaverkanir og í yfirlitsgrein um klínískar rannsóknir var jóhannesarjurt tengd við færri og mildari aukaverkanir miðað við hefðbundin þunglyndislyf. Algengustu aukaverkanirnar í klínískum rannsóknum voru tengdar meltingarveginum (t.d. munnþurrkur, ógleði og breytingar á hægðum), kláði, ljósnæmi, þreyta, svimi, taugaspenningur, svefnleysi og höfuðverkur. Manía hefur einnig komið fram í einstaklingum sem notað hafa jóhannesarjurt.[6]
Notkun jurtalyfja er mög algeng og hefur aukning verið í sölu á milli ára. Ástæðan fyrir þessari miklu notkun er sú að einstaklingar halda að þar sem þetta er náttúrulegt þá eru öll jurtalyf örugg. Hins vegar geta jurtalyf valdið verulegum aukaverkunum og milliverkunum við lyf. [16]
Vitað er að jóhannesarjurt milliverki við ákveðin lyf og veldur því að virkni lyfjanna minnkar, séu þau tekin samhliða jóhannesarjurt. Dæmi um þessi lyf eru:
Jóhannesarjurt getur milliverkað við lyf og haft þannig áhrif á styrk þeirra í blóði. Milliverkunin felur í sér að jóhannesarjurt getur örvað virkni CYP3A4 og P-glýkópróteins sem tekur þátt í umbroti og dreifingu margra lyfja. Gurley o.fl. sýndu fram á verulegan mun á millverkun jóhannesarjurtar við CYP3A4 milli kynja og var hún meiri hjá körlum en konum. [17]
Mikilvægar, og í sumum tilfellum lífshættulegar, milliverkanir hafa komið fram við notkun jóhannesarjurtar, sérstaklega við lyf sem eru hvarfefni cýtókróm P450 og/eða P-glýkópróteins. Vel þekktar milliverkanir eru; (1) minnkaður styrkur cýklósporíns sem komið hefur fram í mörgum skýrslum og klínískum rannsóknum, (2) serótónín heilkenni eða svefnhöfgi þegar jóhannesarjurt er gefin með serótónín endurupptökuhemlum, (3) óæskileg þungun hjá konum sem nota getnaðarvarnarpilluna samhliða jóhannesarjurt og (4) minnkuð plasmaþéttni retróveirulyfja (t.d. indinavir og nevirapine) og krabbameinslyfja (t.d. irinotecan og imatinib). Hyperforin, eitt af virku efnum jurtarinnar, er talið stuðla að flestum þessara milliverkana.[16]
Cýtókróm P450 (CYP) ensím eru algeng ástæða fyrir milliverkunum lyfja í mönnum. Lyf geta virkað hindrandi eða örvandi á CYP ensímin sem leiðir til breytinga á úthreinsun annarra lyfja. Sterkar vísbendingar úr dýrarannsóknum, forklínískum og klínískum rannsóknum benda til þess að jóhannesarjurt geti breytt virkni CYP ensímanna. Margar klínískar rannsóknir hafa sýnt fram á að jóhannesarjurt örvi CYP3A4, CYP2E1 og CYP2C19 en hafi engin áhrif á CYP1A2, CYP2D6 eða CYP2C9. Þessar niðurstöður voru fengnar með því að skoða lyfin alprazolam og miadazolam fyrir CYP3A4, koffín fyrir CYP1A2, klórzoxazón fyrir CYP2E1, dextrometorfan og debrísókín fyrir CYP2D6, tolbútamíð fyrir CYP2C9 og omeprazoll fyrir CYP2C19. Sumar rannsóknir hafa einnig bent til þess að jóhannesarjurt örvi CYP1A2 aðeins í konum. Hyperforin er efnið í jóhannesajurt sem er ábyrgt fyrir þessum milliverkunum en sýnt hefur verið fram á að hyperforin sé öflugur bindill fyrir kjarnaviðtaka sem stjórna tjáningu á CP3A4.[16]
P-glýkóprótein er talið taka virkan þátt í brotthvarfi og frásogi lyfja. Sýnt hefur verið fram á að jóhannesarjurt örvi tjáningu P-glýkópróteins í einangruðum þarmafrumum og í þörmum heilbrigðra manna. Útfrá því hefur verið sýnt fram á minni styrk ýmissa lyfja sem eru hvarfefni P-glýkópróteins í plasma, þar má nefna digoxin, fexófenandín og talinolol. Áhrif jóhannesarjurtar á P-glýkóprótein og CYP ensímin sjást almennt eftir langtímameðferð (10 eða fleiri daga). Upplýsingar um áhrif jóhannesajurtar á CYP og P-glýkóprótein eftir 4-9 daga notkun eru ekki til.[16]
Virkni hyperforins á tjáningu CYP og P-glýkópróteins hefur verið metin í klínískum rannsóknum. Hyperforin er öflugur örvi á CYP3A4 og P-glýkóprótein. Niðurstöður klínískra rannsókna benda til þess að hyperforin ákvarði hversu miklar milliverkanir jóhannesarjurt veldur þar sem útdráttur með litlu magni af hyperforini hafði væg eða engin áhrif á lyf sem bæði eru hvarfefni CYP ensíma og P-glýkópróteina. Klínískar rannsóknir hafa sýnt fram á að útdráttur af jóhannesarjurt sem innihélt lítið magn af hyperforini breytti ekki lyfjahvörfum alprazolams og midazolams (hvarefni CYP3), tolbútamíðs (hvarefni CYP2C), digoxins (hvarefni P-glýkópróteins), cyklósporíns (hvarefni CYP3A4 og P-glýkópróteins), etinýlestradíóls og desógestrels sem eru innihaldsefni getnaðarvarnapilla.[16]
Jóhannesajurt hefur sýnt klínískar milliverkanir við mörg lyf og má þar nefna ónæmisbælandi lyf, getnaðarvarnir, hjartalyf, HIV og krabbameinslyf, kvíðalyf, þunglyndislyf, krampaleysandilyf, svæfingalyf, lyf sem notuð eru við fíkn (t.d. methadón), vöðvaslakandi lyf, lyf sem virka á öndunarfærin, blóðsykurslækkandi lyf, örveruhemjandi lyf, lyf við mígreni og lyf sem virka á meltingarveginn. Einnig getur jóhannesarjurt haft áhrif á blóðþynningarlyf, þá sérstaklega warfarin, ýmis blóðfitulækkandi lyf, eins og statín og ýmsa kalsíumganga- og beta adrenergablokka.[16]
Þekktar frábendingar eru:
Einstaklingur sem er á blóðþynningarlyfjum ætti ekki að nota jóhannesarjurt nema fylgst sé vel með blóðmælingum hjá honum. Hætta ætti notkun jóhannesarjurtar 10 dögum fyrir svæfingu vegna þess að það getur milliverkað við lyf sem notuð eru við svæfingu. Einnig ættu þeir sem eru með Alzheimer og ADHD ekki að nota jóhannesarjurt en einkenni ADHD gætu versnað. Geðhvarfarsýki og geðklofi getur einnig versnað við notkun. Jóhannesartjurt getur hamlað því að eggfruma frjóvgist, haft áhrif á DNA sæðis og aukið niðurbrot á ethinyl estradiol, því ættu einstaklingar sem huga að barneignum ekki að nota jóhannesarjurt. Þeir sem nota eftirfarandi lyf ættu ekki að nota jóhannesarjurt: próteasa hemla, non-núkleósíð bakrita hemla við HIV, cyclosporin, tacrolimus, irinotecan, imatinib mesylate, digoxin. Sérstaklega skal forðast notkun jóhannesarjurtar þegar alprazolam, amitryptilín, fexofenadín, benzodiazepín, methadón, simvastatin, theophyllín, mitazolam, triptans og warfarin eru notuð vegna þess að jurtin getur minnkað virkni þessara lyfja. Þungaðar konur og konur með barn á brjósti ættu ekki að nota jóhannesarjurt. Svo virðist sem notkun jóhannesarjurtar í börnum á aldrinum 6-17 ára í allt að 8 vikur sé mögulega örugg. [6]
Jóhannesarjurt (e. St. John's Wort) er fjölær jurt af ættkvíslinni Hypericum. Jurtin blómstrar í kringum hátíð Jóhannesar skírara (St. John) og er nafn plöntunnar dregið af því. Latneska heiti jurtarinnar er Hypericum perforatum, en Hypericum er komið frá grísku orðunum hyper, sem þýðir "fyrir ofan", og eikon, sem þýðir "mynd". Perforatum vísar til smárra olíukirtla á laufum plöntunnar, ef krómblaðið er kramið kemur dökkrauð olía úr þessum kirtlum.
Jóhannesarjurt vex villt víða um heim, þar með talið í Evrópu, Asíu og Norður Ameríku en hún vex best í ljósum, heitum og sönduðum jarðvegi. Jurtin hefur verið notuð í læknisfræðilegum tilgangi allt frá miðöldum við ýmsum kvillum en í dag er hún helst notuð við vægu þunglyndi.
Mikilvægt er að hafa í huga að þó að jóhannesarjurt sé náttúrulyf getur það milliverkað við önnur lyf og náttúruvörur. Ávallt skal ráðfæra sig við lækni eða annan heilbrigðisstarfsmann áður en byrjað er að nota jóhannesarjurt.
L'iperico (L.) (nome scientifico Hypericum perforatum, ma comunemente nota anche col nome di erba di San Giovanni) è una pianta officinale perenne semisempreverde appartenente alla famiglia delle Clusiaceae (Guttiferae) e al genere Hypericum. Fa parte della medicina tradizionale per via delle sue proprietà fitoterapeutiche, in particolare quelle antidepressive e antivirali[1]. Le origini del suo uso come erba medicinale sono molto antiche e se ne trova traccia negli scritti di molti secoli fa.
L'epiteto specifico perforatum deriva dal fatto che le foglioline, controluce, appaiono bucherellate, effetto dovuto a ghiandole traslucide presenti anche nei sepali e nei petali.
I nomi comuni e volgari sono invece molti. Il più comune è Erba di San Giovanni. Questo epiteto è legato al fatto che la fioritura massima si ha verso il 24 giugno, ricorrenza di San Giovanni[2]. Il nome di erba dall'olio rosso è dovuto al colore dell'essudato rilasciato dai fiori ricco nel principio attivo ipericina; il nome "scacciadiavoli", molto usato nei secoli passati, deriverebbe dal fatto che quest'erba consacrata a San Giovanni e dalle molteplici proprietà terapeutiche, si riteneva fosse efficace contro ogni tipo di male; un'altra spiegazione si ricongiungerebbe ad una delle teorie etimologiche del nome scientifico, ossia quella dell'uso di appenderla sopra le icone per scacciare gli spiriti maligni. Infine il termine pilatro sembra derivi dal greco pylè - "meato", in riferimento alla bucherellatura delle foglie.
È una pianta perenne semi-sempreverde, glabra, con fusto eretto percorso da due strisce longitudinali in rilievo. È ben riconoscibile anche quando non è in fioritura perché le sue foglie in controluce appaiono "bucherellate": si tratta in realtà di piccole vescichette oleose da cui deriva il nome perforatum; ai margini sono invece visibili dei punti neri, strutture ghiandolari contenenti Ipericina (un olio color rosso), queste strutture ghiandolari sono presenti soprattutto nei petali. Le foglie sono opposte oblunghe. I fiori giallo oro hanno 5 petali delicati e sono riuniti in corimbi.
Preferisce boschi radi e luminosi, comunque all'aperto per tutto l'anno, poiché non teme il freddo. Originario dell'arcipelago britannico, è oggi diffuso in tutte le regioni d'Italia e nel resto del mondo. Predilige posizioni soleggiate o semiombreggiate e asciutte, come campi abbandonati ed ambienti ruderali.
Benché già noto alla medicina antica (ne parlano Dioscoride, Galeno, Plinio il Vecchio e Mattioli[3]) l'uso più interessante dell'iperico è scoperta relativamente recente: ormai numerosi studi ne hanno dimostrato l'efficacia antidepressiva, specie nel caso di depressione lieve e moderata, con un effetto paragonabile ad alcuni psicofarmaci antidepressivi.
Una review degli studi al 2008 condotta dalla Cochrane Collaboration, una delle istituzioni scientifiche più autorevoli al mondo, conclude che [4]>>. Alla stessa conclusione giunge una review degli studi pubblicata nel 2016, in cui si sottolinea però che la raccolta e segnalazione degli effetti collaterali è sottoposta ad una sorveglianza meno stringente di quella a cui sono sottoposti i comuni farmaci per cui, nonostante sia in uso da secoli, la sicurezza specie nel lungo termine, non è stata ancora studiata approfonditamente.[5]
Il suo uso è particolarmente diffuso in Germania, dove viene consigliato come trattamento nella depressione negli adolescenti, prima di tentare la via farmacologica.[6] A volte è utilizzato, associato ad altri prodotti, anche per il trattamento fitoterapico di alcune forme d'ansia. Gli studi utilizzano generalmente degli estratti standardizzati di Iperico (spesso prodotti da società svizzere e tedesche col nome di LI 160, WS 5570/2 e ZE 117) ad alta concentrazione di principi attivi (che generalmente si attestano attorno allo 0,3% in ipericina e al 3-6% in iperforina) che la European Scientific Cooperative on Phytotherapy (ESCOP, l'ente scientifico europeo sulla fitoterapia) consiglia di assumere al dosaggio di 300–1800 mg/giorno.[1]
Il meccanismo d'azione antidepressivo dei suoi principi attivi solo ora comincia ad essere delucidato ed appare essere solo parzialmente correlato a quello dei classici farmaci ad oggi più utilizzati. Il principio inizialmente ritenuto attivo era l'ipericina ma i recenti sviluppi hanno chiarito che anche gli altri composti presenti negli estratti contribuiscono sinergicamente all'efficacia. Di questi fanno parte:[7]
L'iperforina è in grado di inibire il reuptake (ricaptazione) della serotonina in modo diverso dagli SSRI (Selective Serotonin Reuptake Inhibitor): mentre questi bloccano l'attività del trasportatore della serotonina (SerT, che funziona grazie ad un gradiente Na+/Cl-) per inibizione competitiva, l'iperforina (e forse gli altri composti attivi) sembrano aumentare il gradiente di sodio e calcio intracellulare influenzando di conseguenza la suddetta pompa Na+/Cl- (che funziona raccogliendo Na+ dallo spazio sinaptico) e riducendo quindi l'attività del SerT. Inoltre si è dimostrata in grado di agire in maniera simile su un ampio altro numero di trasportatori, inibendo la ricaptazione di dopamina, glutammato, noradrenalina e GABA con IC50 (concentrazione di principio attivo che causa una inibizione del 50%) di 0.05-0.1 µg/mL. Tale attività si crede sia dovuta alla capacità dell'ipericina di attivare il transient receptor potential channel protein 6 (TRPC6), un canale ionico appartenente alla più ampia classe dei canali cationici non selettivi (NSCCs, delle proteine in grado di regolare il movimento cellulare di cationi come Na+ e Ca2+) che porta ad un incremento dell'uptake del sodio nel neurone, causando quindi una diminuzione della sua concentrazione nel vallo sinaptico e l'indisponibilità per le proteine trasportatrici per le monoammine.[7] Ciò però non ne spiega completamente l'attività farmacologica: uno studio del 2014 ha mostrato come l'iperforina stesa agisca da agente protonoforo inducendo una corrente di H+ che induce una acidificazione del citosol e un ulteriore incremento delle concentrazioni di sodio intracellulari.[8] Al contrario di quanto causato dagli antidepressivi serotoninergici, l'iperforina si è dimostrata in grado di incrementare il numero di recettori per la serotonina a seguito di somministrazione cronica, suggerendo un potenziale effetto benefico.[9]
L'ipericina ha dimostrato avere forte affinità per i recettori sigma, i quali regolano a loro volta i livelli di dopamina. Inoltre agisce da antagonista sui recettori per l'adenosina, GABA-A, GABA-B e inositoli trifosfati, i quali regolano i potenziali d'azione causati dai neurotrasmettitori. Altri studi hanno dimostrato come l'ipericina sia un inibitore degli enzimi Mono Ammino Ossidasi (il target farmacologico degli antidepressivi cosiddetti MAOI) anche se tale azione non sembra essere significativa alle concentrazioni normalmente raggiunte con l'uso degli estratti.[7]
Gli estratti hanno poi notevoli proprietà antiossidanti e neuroprotettive, nonché di miglioramento delle proprietà vascolari, che ne hanno suggerito l'uso in alcune patologie neurologiche.[7] Per tali proprietà, degli studiosi affermano che gli estratti di iperico dovrebbero essere un trattamento di prima scelta della depressione negli anziani con elevato stress ossidativo.[10]
Queste qualità possono però essere sfruttate solo da preparazioni farmaceutiche perché in Italia una disposizione del Ministero della Salute limita la quantità di ipericina presente in prodotti erboristici a 21 microgrammi al giorno, quindi molto inferiore ai dosaggi dimostrati utili per la cura della depressione e perciò priva di utilità pratica, essendo inoltre stato dimostrato in diversi trial che la concentrazione di iperforina è direttamente proporzionale agli effetti terapeutici.[1]
Nella medicina tradizionale l'iperico è usato come antisettico. Tali usi sono in parte dovuti alle proprietà antibatteriche e antivirali dell'iperforina che è in grado di bloccare la crescita di batteri Gram+ (ma non Gram-), in particolare di ceppi resistenti ad altri antibiotici come Methicillin-resistant (MRSA) e penicillin-resistant (PRSA) Staphylococcus aureus, e interferire in vari stadi del ciclo vita dei virus incapsulati compreso quello dell'influenza, specie quando attivata dalla luce.[7]
Nella fitoterapia tradizionale, invece, dell'iperico sono state valorizzate principalmente le qualità astringenti, antinfiammatorie e antibatteriche, anche per uso interno ma soprattutto per uso esterno nel trattamento di scottature, emorroidi, ferite, piaghe.[11]. A tal fine viene preparato sotto forma di olio di iperico, un oleolito dal caratteristico colore rosso, preparato macerando la pianta nell'olio di oliva al sole per 6-7 giorni.
Nel trattamento delle ferite, la sua capacità sembra essere dovuta alla stimolazione della produzione di collagene; gli estratti di iperico sembrano possedere attività antinfiammatorie per inibizione di geni proinfiammatori come quelli delle COX-2, interleuchine-6 e iNOS.[7]
Tutti i più recenti trial clinici e revisione di studi concludono che gli estratti di iperico sono più tollerabili dei più comuni psicofarmaci, causando minori effetti collaterali e con tassi di miglioramento spesso simili al farmaco. Tuttavia sono possibili pericolose interazioni con diversi farmaci.[1][7]
La macerazione in olio utilizzata per la preparazione dell'olio di iperico, invece, fa degradare l'ipericina eliminando così buona parte delle controindicazioni ma anche l'attività antidepressiva.
L'iperico (L.) (nome scientifico Hypericum perforatum, ma comunemente nota anche col nome di erba di San Giovanni) è una pianta officinale perenne semisempreverde appartenente alla famiglia delle Clusiaceae (Guttiferae) e al genere Hypericum. Fa parte della medicina tradizionale per via delle sue proprietà fitoterapeutiche, in particolare quelle antidepressive e antivirali. Le origini del suo uso come erba medicinale sono molto antiche e se ne trova traccia negli scritti di molti secoli fa.
Paprastoji jonažolė (lot. Hypericum perforatum, angl. St John's wort, vok. Echtes Johanniskraut) - daugiametis žolinis augalas, priklausantis jonažolinių (Hypericaceae) šeimos jonažolių (Hypericum) genčiai.
Užauga iki metro aukščio. Stiebas stačias, viršutinėje dalyje šakotas; lapai priešiniai, ovalūs, lygiais kraštais; žiedai geltoni, susitelkę į šluoteles. Vaisius - dėžutė. Auga pievose, sausuose retuose miškuose, šlaituose, pagrioviuose[1]. Mėgsta saulėtas sausas vietas. Žydi ir vaisius brandina visą vasarą.
Jonažolė turi daug biologiškai aktyvių medžiagų: vitaminų C, E, P, karotino, dažinių rauginių medžiagų, mikroelementų.
Vaistinė žaliava - stiebų viršūnėlės su žiedais ir lapeliais, kurie pjaunami žydėjimo metu. Žmonės jonažolę vadina „vaistu nuo 99 ligų“. Negalima vartoti būnant saulėje, nes gali atsirasti alerginiai odos pažeidimai.
Dažniausiai vartojama dezinfekcijai kaip priešuždegiminė, surišančioji, reguliuojanti medžiagų apykaitą priemonė. Vartojama esant inkstų uždegimams, akmenligei, virškinamojo trakto veiklai reguliuoti, kvėpavimo takų ligoms gydyti. Mažina kraujagyslių pralaidumą.
Išoriškai vartojama žaizdas gydanti, regeneraciją skatinanti priemonė. Nuoviru plaunamos pūlingos žaizdos, flegmonos, abscesai. Sergant stomatitu, skalaujama burnos ertmė.
Jonažolė šiek tiek mažina depresiją, baimę. Vartojama nerviniams ir su didele baime susijusiems kvėpavimo sutrikimams gydyti. Vienai antpilo porcijai reikia 1-2 arbatinių šaukštelių žolės. Gerti 2-3 kartus per dieną kelias savaites.
Paprastoji jonažolė (lot. Hypericum perforatum, angl. St John's wort, vok. Echtes Johanniskraut) - daugiametis žolinis augalas, priklausantis jonažolinių (Hypericaceae) šeimos jonažolių (Hypericum) genčiai.
Užauga iki metro aukščio. Stiebas stačias, viršutinėje dalyje šakotas; lapai priešiniai, ovalūs, lygiais kraštais; žiedai geltoni, susitelkę į šluoteles. Vaisius - dėžutė. Auga pievose, sausuose retuose miškuose, šlaituose, pagrioviuose. Mėgsta saulėtas sausas vietas. Žydi ir vaisius brandina visą vasarą.
Jonažolė turi daug biologiškai aktyvių medžiagų: vitaminų C, E, P, karotino, dažinių rauginių medžiagų, mikroelementų.
Divšķautņu asinszāle (latīņu: Hypericum perforatum) ir asinszāļu dzimtai piederošs ārstniecības augs, ko tautas medicīnā lieto pret dažādām ar asinsrites darbību saistītām kaitēm, sāpēm un krampjiem, bezmiegu un depresiju, kā arī citiem veselības traucējumiem. Klīniskajos pētījumos visvairāk pierādītas auga antidepresanta īpašības.
Lai arī dažviet divšķautņu asinszāle tiek īpaši kultivēta kā vērtīgs ārstniecības augs, daudzi jau gadsimtiem to uzskata par indīgu nezāli. Lopiem šis augs ir ļoti kaitīgs un tā apēšana var novest līdz centrālās nervu sistēmas traucējumiem, spontānam abortam un pat nāvei.
Dzimtas bioloģiskais nosaukums “hypericum” cēlies no grieķu valodas vārdiem hyper - virs un eikon - ikona, attēls, bilde un saistīts ar seno tradīciju Sv. Jāņa Kristītāja dienā, t.i., 24. jūnijā, kad tiek svinēti arī vasaras saulgrieži, pakārt ziedošos augus mājās virs kāda attēla, lai aizdzītu prom ļaunumu un ļaunos garus. No šīs paražas arī cēlies auga angliskais nosaukums — “St. John's Wort” jeb “Svētā Jāņa ārstniecības zāle“. Sugas nosaukumā ietvertais vārds “perforatum” norāda uz mazajiem caurumiņiem asinszāles lapās, ko var labi aplūkot, paceļot un turot augu pret gaismu.
Divšķautņu asinszāle ir daudzgadīgs, 30–100 cm garš lakstaugs ar augšdaļā zarotu stublāju, iegarenām lapām un dzelteniem, skarās sakārtotiem ziediem. Asinszāle zied no jūlija līdz septembrim. Tās ziedu auglis ir pogaļa.
Ārstnieciskā asinszāle aug Eiropā un Amerikā. Bieži sastopama pļavās, mežos un pie tīrumiem.
Lielās devās asinszāle ir indīga ganāmpulka dzīvniekiem (liellopi, aitas, kazas, zirgi).[1] Saindēšanās pazīmes ir nemiers un fotosensivitāte. Dzīvnieki vāļājas gar zemi, purina galvu, spontāni krīt un ir apjukuši. Iespējama mānija un hiperaktivitāte, dzīvnieki skrien riņķī uz apli līdz pārgurst.
Fotosensivitātes dēļ āda ir kairināta un stipri niez, iespējami plaši ādas apdegumi un iekaisums. Lopi censas uzturēties ēnā.
Tāpat novērojama augsta temperatūra, paātrināta sirdsdarbība un apetītes zudums. Nāve galvenokārt iestājas no ilgstošas barības neuzņemšanas un novājēšanas, kā arī ādas slimībām.
Asinszāli tautas medicīnā lieto asinsrites sistēmas uzlabošanai un ar asinsriti saistītu slimību, piemēram, anēmijas ārstēšanai. Uzskata, ka asinszāle attīra asinis organismā, un aptur asiņošanu, to lieto arī pie menstruāciju traucējumiem. Drogai piedēvē antiseptiskas un pretiekaisuma īpašības; to izmanto iekšķīgi kuņģa un zarnu trakta iekaisumu gadījumos, kuņģa čūlas, aknu un aizkuņģa dziedzera saslimšanas gadījumos, kā arī ārīgi — dažādu mutes dobuma gļotādas iekaisumu ārstēšanai. Vēl asinszāli lieto pret sāpēm, piemēram, — stiprām galvassāpēm, un krampjiem.
Asinszāle ir pazīstams ārstnieciskais līdzeklis depresijas ārstēšanai. Asinszāles drogas palīdz pret bezmiegu, spriedzi, dažādām neirozēm. Pēdējā laikā Eiropā to izmanto kā alternatīvu ķīmiski sintezētajiem antidepresantiem (Vācijā asinszāles preparāti ir recepšu zāles). Lielākajā daļā jaunāko klīnisko pētījumu asinszāles efektivitāte ir pierādīta kā līdzvērtīga farmācijas ražotajiem antidepresantiem (SSRI) vai kā nedaudz vājāka.[2]
Par auga stiprākajām aktīvajām vielām uzskata hipericīnu, pseidohipericīnu un hiperforīnu, kuru pussabrukšanas laiks cilvēku organismā svārstās no 15—60 stundām.[3]
Asinszāle retos gadījumos var radīt vieglas nevēlamas blakusparādības, piemēram, reiboni, apjukumu un nogurumu.[4][5] Pie lielu devu lietošanas ir novērota paaugstināta fotosensivitāte (netolerance pret gaismu, paaugstināts risks gūt ādas apdegumus intensīvā dienasgaismā).[6] Pacientiem ar bipolārajiem traucējumiem divšķautņu asinszāle var pastiprināt māniju,[7]
Asinszāle izmaina daudzu vielu iedarbību. Asinszāli nedrīkst lietot kopā ar citiem antidepresantiem, varfarīnu un orālo kontracepciju.
Asinszāle var samazināt vairāku zāļu efektivitāti, to vidū ir gan medikamenti HIV/AIDS ārstēšanai, orālā kontracepcija, benzodiazepīni, bēta adrenoblokatori, kalcija kanālu blokatori, līdzekļi holesterīna mazināšanai un sirds aritmijas ārstēšanai, varfarīns, L-DOPA, metadons, fenobarbitāls un citi.[8]
Asinszāli nedrīkst lietot kopā ar citiem līdzekļiem, kas ceļ serotonīna līmeni, it īpaši citiem antidepresantiem, jo ir risks iegūt serotonīna sindromu, kas var būt potenciāli nāvējošs.[9]
Vielas, ko ir bīstami lietot ar divšķautņu asinszāli Klase Vielas Antidepresanti MAOI, TCA, SSRI, SNRI, mirtazapīns Opioīdi tramadols, petidīns (meperidīns), levorfanols Stimulanti fentermīns, dietilpropions, amfetamīns, sibutramīns, kokaīns 5-HT1 agonisti triptāns Psihedēliskās vielas MDMA, LSD, DMT, MDA, 6-APB Citi selegilīns, triptofāns, busfirons, litijs, linezolīds, 5-HTP, dekstrometorfāns Avots:[10]Divšķautņu asinszāles preparātiem ir izteikta savelkoša un antimikrobiāla iedarbība; tie sekmē audu reģenerāciju. Uzlējumu, tēju, tinktūru un sauso ekstraktu ārīgi lieto pret smaganu un mutes gļotādu iekaisumu, otrās un trešās pakāpes apdegumu ārstēšanai, brūču dziedēšanai. Iekšķīgi tos lieto kolītu (resnās zarnas gļotādas iekaisumu), aknu, žultspūšļa slimību, cistītu, kuņģa un zarnu trakta čūlu ārstēšanai. Asinszāļu laksti ietilpst dažādās savelkošās jauktajās tējās. No divšķautņu asinszāles lakstiem Bulgārijā ražo preparātu deflavītu, kuru izmanto kā P vitamīnu. Preparātus imanīnu un novoimanīnu izgatavo kā sausos ekstraktus un lieto dažādās zāļu formās ādas slimību un apdegumu ārstēšanai. Tautas medicīnā lieto reimatisma, podagras, hemoroīdu ārstēšanai, pret iekšējām asiņošanām, bērniem pret urīna nesaturēšanu naktīs un kā diurētisku līdzekli. Asinszāļu lakstu eļļas izvilkumu (1 daļu lakstu aplej ar 2 daļām eļļas un ekstrahē 3 nedēļas istabas temperatūrā) lieto kompresēs apdegumu brūču un čūlu ārstēšanai. Asinszāļu lakstus kā krāsvielu plaši lieto liķieru, balzamu un citu alkoholisko dzērienu gatavošanā. Drogu pagatavošanai izmanto auga ziedus un galotnes, ko ievāc tā ziedēšanas laikā un žāvē līdz 35 °C t ēnā.
Asinszāles tējas pagatavošanai izmanto 1 ēdamkaroti drogu, ko:
Asinszāli nedrīkst lietot neierobežotā daudzumā karstā vai saulainā laikā un apmeklējot solāriju.
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|df=|Hypericum perforatum Divšķautņu asinszāle (latīņu: Hypericum perforatum) ir asinszāļu dzimtai piederošs ārstniecības augs, ko tautas medicīnā lieto pret dažādām ar asinsrites darbību saistītām kaitēm, sāpēm un krampjiem, bezmiegu un depresiju, kā arī citiem veselības traucējumiem. Klīniskajos pētījumos visvairāk pierādītas auga antidepresanta īpašības.
Lai arī dažviet divšķautņu asinszāle tiek īpaši kultivēta kā vērtīgs ārstniecības augs, daudzi jau gadsimtiem to uzskata par indīgu nezāli. Lopiem šis augs ir ļoti kaitīgs un tā apēšana var novest līdz centrālās nervu sistēmas traucējumiem, spontānam abortam un pat nāvei.
Het sint-janskruid (Hypericum perforatum) is een plant uit de hertshooifamilie (Hypericaceae). De vaste plant komt van nature oorspronkelijk voor in Europa, maar is van daaruit verder verspreid. Het kruid bloeit rond het Sint-Jansfeest op 24 juni, de tijd dat de zon op zijn hoogst staat, met gele bloemen die dan ook worden geoogst.
De soort is al lang in gebruik als geneeskrachtig kruid en is als plantaardig antidepressivum verkrijgbaar.
De plant wordt 20-85 cm hoog en heeft een ronde stengel met tot twee smalle lijsten. De kale, elliptisch tot eironde, gaafrandige, 1,5-3 cm lange bladeren hebben talrijke doorzichtige punten en een stompe bladvoet. De doorzichtige puntjes zijn gevuld met etherische olie. Sint-janskruid bloeit van juni tot september met gele bloemen. De kroonbladen zijn 1-1,6 cm lang. De kelkbladen zijn lancetvormig, spits en gaafrandig. De kroonbladen hebben weinig zwarte punten. De bloeiwijze is een tuil.
De vrucht is een doosvrucht met, uitsluitend lange, klierstrepen (vittae).
De plant komt voor op droge, grazige, voedselrijke plaatsen langs wegen, spoorwegen en struikgewas.
Neem het voorbehoud bij medische informatie in acht.Verschillende stoffen in sint-janskruid kunnen verantwoordelijk zijn voor de aan fytotherapeutische bereidingen van deze plant toegeschreven antidepressieve effecten. De hypericinen worden als de belangrijkste psychoactieve stoffen in de plant beschouwd, met name gaat het dan om hypericine, pseudohypericine en hyperforine. De meeste wetenschappelijke studies met Hypericum zijn uitgevoerd met een op 0,3% hypericine gestandaardiseerd extract, waaraan in de medische literatuur gerefereerd wordt als "LI 160". Een aantal gestandaardiseerde hypericumproducten op de markt zijn gemodelleerd naar dit voorbeeld en zijn eveneens gestandaardiseerd op 0,3% hypericine.
De samenstelling van de verschillende sint-janskruidpreparaten varieert sterk. Sommige bevatten alleen hypericine, maar blijken toch werkzaam.[1] Sint-janskruid remt, net als de conventionele antidepressiva, de neuronale heropname van serotonine, noradrenaline en dopamine. Tevens remt het de heropname van GABA en L-glutamaat.[2] Ongeveer 20% van de hypericine wordt geabsorbeerd en komt na 1 à 2 uur in de bloedstroom. Hypericine heeft een relatief lange halfwaardetijd en blijft meer dan 24 uur in de bloedstroom.
Een eerste studie uitgevoerd bij mensen met een zware depressie liet geen effect zien van sint-janskruid, mogelijk doordat deze studie te klein van opzet was.[3] Een latere, grotere studie, waarbij ook mensen met mildere depressies werden bestudeerd, liet wel een effect zien.[4] Bij matige tot zware depressies is er namelijk wel bewijs voor de werkzaamheid.[5][6]
Diverse kleinere studies wijzen erop dat sint-janskruid bij de behandeling van lichte tot matige depressie effectiever is dan een placebo en net zo effectief als tricyclische antidepressiva. Deze conclusie wordt ondersteund door verschillende meta-analyses en een Cochrane review[7] van verschillende studies. Vergelijkingen met selectieve serotonine-heropnameremmers (SSRI's) laten geen consistent beeld zien, waardoor daar nog geen conclusies getrokken kunnen worden over de effectiviteit van sint-janskruid in vergelijking met deze groep antidepressiva.
Sint-janskruid wordt ook gebruikt als middel tegen stress en slapeloosheid, al zijn er ook aanwijzingen dat het - net als sommige conventionele antidepressiva - slapeloosheid kan veroorzaken. Depressie gaat vaak gepaard met slapeloosheid, vandaar dat het in deze gevallen wel slapeloosheid kan verlichten. Bij primaire slapeloosheid (dus niet als gevolg van een depressie) kan het dus averechts werken. In de vorm van Sint-Jansolie kan het gebruikt worden tegen brandwonden en zonnebrand.
Het Nederlandse College ter Beoordeling van Geneesmiddelen (CBG) heeft in 2007 een preparaat van sint-janskruid (merknaam Hyperiplant) geregistreerd als medicijn tegen een milde of matige depressie.[8] Volgens het CBG heeft de aanvrager (VSM Geneesmiddelen) de werking van het product voldoende aangetoond. Het CBG denkt dat de veiligheid van patiënten verbetert door registratie, aangezien mogelijke bijwerkingen en interacties via het geneesmiddelenbewakingssysteem sneller zullen worden opgemerkt.
Sint-janskruidpreparaten worden over het algemeen goed verdragen.
Mogelijke bijwerkingen:
In het Nederlands Tijdschrift voor Geneeskunde is een casus gemeld van een patiënt met zelfmoordgedachten en agressiviteit die mogelijk verband houden met het gebruik van sint-janskruid.[10]
Sint-janskruid kan de werking van geneesmiddelen nadelig beïnvloeden. Het versterkt de werking van het lever-enzymsysteem cytochroom P450,[11][12] waardoor een aantal geneesmiddelen sneller wordt afgebroken en daardoor een geringere werking heeft. Zo kan het gebruik van sint-janskruid onder andere de werking van de anticonceptiepil verminderen.[13] Tevens wordt de activiteit van het transporteiwit P-glycoproteïne verhoogd met eenzelfde effect.
Waargenomen is dat gezondheidsproducten met sint-janskruid de werking van de volgende geneesmiddelen kunnen verminderen:[14]
Sint-janskruid kan de werking van antidepressiva beïnvloeden. Dit geldt ook indien een tricyclisch antidepressivum, bijvoorbeeld amitriptyline, bij neuropathie wordt gebruikt. Sint-janskruid verhoogt, zoals veel antidepressiva, de hoeveelheid serotonine in de hersenen. In combinatie met een MAO-remmer, een SSRI of clomipramine bestaat er hierdoor kans op het ontstaan van het serotoninesyndroom.[18]
Gelijktijdig gebruik van sint-janskruid en een antidepressivum wordt daarom afgeraden. Om deze reden is het sinds november 2001 verplicht om op de verpakking of in de bijsluiter van producten die sint-janskruid bevatten een tekst te vermelden waarin gewaarschuwd wordt voor de effecten op medicatie.
In de oudheid werd sint-janskruid gebruikt bij brandwonden en andere wonden.[19] Hippocrates en Paracelsus hebben dit gebruik beschreven.
Sint-Janskruid is in alle Europese cultuur een belangrijke plant, er zijn vele legenden aan de plant verbonden, en in een aantal gevallen was het zelfs een cultusplant. Het kruid is genoemd naar Sint-Jan, omdat het hoogtepunt van de bloei op de feestdag van Sint-Jan valt (24 juni), ook is St. Jan de Heilige van het Licht, zijn feest valt in de periode van het oude Midzomerfeest, waaraan de Sint-Jansvuren nog herinneren. De rode olie die de plant bevat heeft voor veel legendevorming geleid, bij de oude Germanen zou het, het bloed zijn geweest van Baldur, de Germaanse God van de Natuur, de Zomer en het Licht, maar ook het bloed van Wodan nadat hij door een everzwijn was verwond. Aan het kruid werden allerlei magische krachten toegedicht, bijvoorbeeld bond men het op daken om te beschermen tegen onweer, ook waren er vruchtbaarheidsrituelen verbonden aan het kruid, bijvoorbeeld een vrouw die graag kinderen wilde moest op Midzomernacht, naakt het kruid plukken.
De bijnaam "jaag den duvel" geeft aan dat sint-janskruid volgens overleveringen vroeger ook wel als afweerkruid werd gebruikt om zich te beschermen tegen hekserij, magie of andere mogelijke gevaren.
Bronnen, noten en/of referenties
Mediabestanden die bij dit onderwerp horen, zijn te vinden op de pagina Hypericum perforatum op Wikimedia Commons. 
(Nederlandstalige) Wikisource.Het sint-janskruid (Hypericum perforatum) is een plant uit de hertshooifamilie (Hypericaceae). De vaste plant komt van nature oorspronkelijk voor in Europa, maar is van daaruit verder verspreid. Het kruid bloeit rond het Sint-Jansfeest op 24 juni, de tijd dat de zon op zijn hoogst staat, met gele bloemen die dan ook worden geoogst.
De soort is al lang in gebruik als geneeskrachtig kruid en is als plantaardig antidepressivum verkrijgbaar.
Prikkperikum eller johannesurt (latin: Hypericum perforatum) er en flerårig urt i perikumslekten av perikumfamilien (Clusiaceae). Den blir 20–80 centimeter høy og har eggrunde og svakt perforerte små blad, og sterkt gule blomster med fem kronblad. Stilken er grå nederst og grønn øverst og tidvis betydelig greinet.
Prikkperikum har helt siden oldtiden vært en kjent og mye benyttet medisinplante. Hippokratus, Dioskurides og Paracelsus mente planten virket helbredende ved nervøse forstyrrelser. Paracelsus, som var en av historiens mest berømte leger, skrev følgende: «Enhver lege bør vite at Vår Herre har lagt en stor hemmelighet i denne urten, for å beseire de ånder og fantasier som driver mennesker til randen av fortvilelse.»
Prikkperikum vokser vilt i store deler av landet. Det har blitt funnet prikkperikum så langt nord som til Sør-Varanger. Stengelen er oppreist og vedaktig med parvis motsatte blader. Planten blomstrer fra juli og utover hele sommeren med gule blomster som vokser i klaser. Blomstene inneholder stoffet hypericin, som kan ses som små prikker i kronbladene. Det latinske navnet antyder at bladene er perforerte, noe som kan bero på disse dråpene av hypericin.
Det er lett å identifisere denne planten: Hvis man gnir en blomst i hånden blir fingrene farget røde av hypericinet. Stengelen har to kanter, noe som skiller den fra slektningen firkantperikum (Hypericum maculatum), som har fire. I motsetning til firkantperikum har dessuten prikkperikum få eller ingen svarte prikker på kronbladene. Prikkperikum kan derimot ha noe svarte prikker på de godt skjulte begerbladene under kronbladet.
Prikkperikum blir brukt som krydder til brennevin, og det er denne planten Ulf Lundell synger om i sangen «Öppna landskap». Når de gule blomstene blir lagt i brennevin, blir brennevinet farget kraftig rødt, noe som i tidligere tider har ført til en tro på at planten har magisk kraft. På grunn av denne rødfargen har planten også fått navn etter døperen Johannes – man mente rødfargen var Johannes’ blod – og vi ser dette går igjen i de svenske, engelske og tyske navnene på planten. Gjennom tidene har planten blitt brukt som universalmedisin mot en lang rekke plager.
I våre dager påstås prikkperikum å ha en effekt mot tungsinn, altså lette depresjoner, og dette har etter hvert blitt gjenstand også for seriøs forskning. Det finnes seks naturlegemidler basert på prikkperikum tillatt solgt gjennom apotek i Norge.
Bruk av planten er kjent for å virke fotosensibiliserende, noe som kan føre til utslett i forbindelse med soling. Dessuten er det påvist at prikkperikum hemmer effekten av visse legemidler, deriblant proteasehemmere og betablokkere, og det foreligger mistanke om at en rekke andre legemidler også får svekket effekt ved samtidig bruk av preparater av denne planten. Hormonelle prevensjonsmidler er trolig det best kjente eksempelet på dette.
Prikkperikum eller johannesurt (latin: Hypericum perforatum) er en flerårig urt i perikumslekten av perikumfamilien (Clusiaceae). Den blir 20–80 centimeter høy og har eggrunde og svakt perforerte små blad, og sterkt gule blomster med fem kronblad. Stilken er grå nederst og grønn øverst og tidvis betydelig greinet.
Prikkperikum har helt siden oldtiden vært en kjent og mye benyttet medisinplante. Hippokratus, Dioskurides og Paracelsus mente planten virket helbredende ved nervøse forstyrrelser. Paracelsus, som var en av historiens mest berømte leger, skrev følgende: «Enhver lege bør vite at Vår Herre har lagt en stor hemmelighet i denne urten, for å beseire de ånder og fantasier som driver mennesker til randen av fortvilelse.»
Prikkperikum vokser vilt i store deler av landet. Det har blitt funnet prikkperikum så langt nord som til Sør-Varanger. Stengelen er oppreist og vedaktig med parvis motsatte blader. Planten blomstrer fra juli og utover hele sommeren med gule blomster som vokser i klaser. Blomstene inneholder stoffet hypericin, som kan ses som små prikker i kronbladene. Det latinske navnet antyder at bladene er perforerte, noe som kan bero på disse dråpene av hypericin.
Det er lett å identifisere denne planten: Hvis man gnir en blomst i hånden blir fingrene farget røde av hypericinet. Stengelen har to kanter, noe som skiller den fra slektningen firkantperikum (Hypericum maculatum), som har fire. I motsetning til firkantperikum har dessuten prikkperikum få eller ingen svarte prikker på kronbladene. Prikkperikum kan derimot ha noe svarte prikker på de godt skjulte begerbladene under kronbladet.
Dziurawiec zwyczajny (Hypericum perforatum L.) – gatunek rośliny należący do rodziny dziurawcowatych. Występuje naturalnie w Europie (w tym pospolicie w Polsce), zachodniej Azji, północnej Afryce. Zawleczony został do Ameryki Północnej i Południowej, południowej Afryki, Australii i Nowej Zelandii, Japonii[2]. Znajduje zastosowanie w medycynie, rolnictwie, a także jako roślina ozdobna.
Bylina, hemikryptofit. Siedlisko: ciepłolubne dąbrowy, trawiaste zarośla, ciepłolubne murawy, także ubogie, miedze. Kwitnie od czerwca do sierpnia, wytwarza dużo pyłku, z którego korzystają owady odwiedzające kwiaty.
Tworzy mieszańce z dziurawcem czterobocznym i dz. skrzydełkowatym[3].
W starożytnej Grecji stawiano w domach gałązki dziurawca nad obrazkami, czy posążkami, aby odpędzić złe duchy, wierząc w mistyczną siłę tej rośliny, co przypuszczalnie dało początek nazwie łac. hypericum od gr. hyper – „nad”, eikon – „ikona”. Nazwa „dziurawiec” jak i drugi człon nazwy łac. perforatum – dosłownie „dziurawy” – pochodzą od charakterystycznego wyglądu liści.
Z kolei nazwę zwyczajową – ziele świętojańskie czy też ziele Świętego Jana, ang. St John's wort – dziurawiec zyskał z powodu kwitnienia w dniu Świętego Jana, tj. 24 czerwca[4]. Wymieniany też pod nazwami: dziurawiec pospolity, ruta polna, krzyżowe ziele, arlika[5], przestrzelon, dzwonki Panny Marii[6]. Ze względu na swoje właściwości uczulające dziurawiec zwyczajny jest w Rosji nazywany: zwieroboj, co dosłownie oznacza zwierzobójca.
Dziurawiec jest jedną z najlepiej poznanych roślin leczniczych i często znajduje zastosowanie w ziołolecznictwie.
Surowiec zielarski pochodzący z dziurawca zwyczajnego tj. zebrane i ususzone jego kwiatostany określa się mianem ziela dziurawca (łac. Hyperici herba). Zawiera ono czerwony barwnik hiperycynę, pseudohiperycynę, hyperforynę, flawonoidy (rutyna, kwercetyna), hiperozyd, bakteriobójcze garbniki, witaminy A i C oraz olejek eteryczny[4].
Suchy wyciąg z dziurawca uzyskany poprzez ekstrakcję alkoholem może zmniejszać objawy łagodnej lub umiarkowanej depresji. Mechanizm działania jest trudny do określenia ze względu na różnorodność substancji zawartych w dziurawcu. Żadna z substancji zawartych w dziurawcu zastosowana z osobna w dawkach odpowiadających leczeniu dziurawcem nie posiada działania wystarczająco silnego do uzyskania efektu przeciwdepresyjnego. Przyjmuje się, że dopiero współdziałanie ze sobą owych aktywnych biologicznie substancji zawartych w dziurawcu pozwala na uzyskanie efektu przeciwdepresyjnego. Obecnie największe znaczenie dla działania przeciwdepresyjnego przypisuje się hyperforynie, a w mniejszym stopniu hyperycynie i flawonoidom. Przypuszcza się, że główne mechanizmy pośredniczące w tym działaniu to hamowanie zwrotnego wychwytu serotoniny, noradrenaliny i dopaminy oraz słabe hamowanie enzymu monoaminooksydazy odpowiadającej za rozkład serotoniny, noradrenaliny i dopaminy (neurotransmiterów w mózgu). Poza tym wykazano powinowactwo substancji zawartych w dziurawcu m.in. do receptorów adenozynowych, GABA i glutaminianowych. Wykazano także, że składniki dziurawca na modelach zwierzęcych powodują desensytyzację receptorów beta-adrenergicznych i sensytyzację receptorów serotoninowych 5-HT2. Dziurawiec wpływa także na ekspresję genów zaangażowanych w regulację osi podwzgórzowo-przysadkowo-nadnerczowej[7][8][9][10]. Efektom przeciwdepresyjnym dziurawca może towarzyszyć działanie przeciwlękowe i zmniejszenie bezsenności. Co więcej, według części badaczy, dziurawiec w części przypadków może być lepiej tolerowany od leków przeciwdepresyjnych[4].
Podczas stosowania dziurawca należy unikać światła słonecznego, gdyż zawarta w nim hyperycyna może spowodować reakcje fototoksyczne[11]. W związku z tym nie zaleca się stosowania dziurawca dla osób z nadwrażliwością na światło słoneczne, o jasnej karnacji skóry, osobom intensywnie eksponującym się na światło słoneczne lub osobom z chorobowymi zmianami skóry. Przeciwwskazane jest stosowania dziurawca w depresji o wysokim nasileniu ze względu na brak wystarczających dowodów na jego skuteczność w takich przypadkach oraz jego niższą skuteczność w tych przypadkach niż leków przeciwdepresyjnych[4].
Dziurawiec może powodować interakcje z lekami. Nie należy spożywać preparatów z dziurawca podczas stosowania doustnych tabletek antykoncepcyjnych[11]. Nasila działanie przeciwzakrzepowe antagonistów witaminy K (acenokumarol, warfaryna). Nie należy przyjmować z innymi lekami przeciwdepresyjnymi (MAOI, SSRI) oraz z dekstrometorfanem, podczas suplementacji tryptofanem i 5-HTP, z uwagi na kazuistyczne doniesienia wskazujące, iż dziurawiec może spowodować potencjalnie śmiertelny zespół serotoninowy. Ponadto stosowany łącznie z teofiliną, digoksyną lub lekami antyretrowirusowymi obniża ich poziom w organizmie, a co za tym idzie obniża ich skuteczność i może być przyczyną komplikacji. Część interakcji dziurawca wynika z indukcji wątrobowego cytochromowego izoenzymu CYP3A4, co może przyśpieszać eliminację z organizmu wielu różnych substancji i leków. W związku z tym przed zastosowaniem ziela dziurawca należy skonsultować się z lekarzem lub farmaceutą[4].
Dostępne w sprzedaży są stosowane w stanach depresyjnych tabletki zawierające suchy wyciąg z dziurawca uzyskany przez ekstrakcję alkoholem oraz wyciąg alkoholowy ze świeżego ziela dziurawca (łac. Intractum Hyperici), a także stosowane w zaburzeniach trawiennych zioła do zaparzania (łac. Hyperici herba) i sok z dziurawca (łac. Succus Hyperici). Ponadto dziurawiec wchodzi w skład licznych mieszanek ziołowych i preparatów złożonych.
U osób dorosłych w przypadkach łagodnej lub umiarkowanej depresji zwykle zaleca się dawki 300–1200mg na dobę suchego wyciągu z dziurawca uzyskanego poprzez ekstrakcję alkoholem[4]. Przyrządzanie nalewki z ziela dziurawca – 100 g ziela dziurawca zalać 500 g spirytusu i odstawić na 7 dni. Po tym okresie przecedzić i wycisnąć przez gazę.
Zewnętrznie stosuje się do nacierania w bólach stawowych. Wewnętrznie stosować 2 razy dziennie po 1 łyżeczce na pół szklanki wody w chorobach wątroby, układu pokarmowego i dróg żółciowych[potrzebny przypis].
Stosowany również jako roślina dekoracyjna. Nadaje się w ogródkach ziołowych lub sadzony na np. rabatach bylinowych. Przydatny w silnie nasłonecznionych miejscach.
W rolnictwie, masowo występując na łąkach obniża jakość siana. Czerwony barwnik zawarty w kwiatach barwi mleko krów żywiących się takim sianem. Także negatywnie wpływa na zwierzęta o jasnej skórze, wywołując uczulenie na światło. Zwierzęta karmione paszą z dużą ilością dziurawca mogą cierpieć na stany zapalne skóry.
Roślina rośnie najlepiej na ciepłych i nasłonecznionych stanowiskach. Nie jest wybredna względem gleby. Ważne by nie była nazbyt zlewna, podmokła oraz jałowa. Preferuje gleby żyzne i przepuszczalne z domieszką piasku. Przed zimą część nadziemna całkowicie obumiera. W warunkach środkowoeuropejskich roślina całkowicie mrozoodporna (strefa mrozoodporności 5)[12].
Dziurawiec zwyczajny (Hypericum perforatum L.) – gatunek rośliny należący do rodziny dziurawcowatych. Występuje naturalnie w Europie (w tym pospolicie w Polsce), zachodniej Azji, północnej Afryce. Zawleczony został do Ameryki Północnej i Południowej, południowej Afryki, Australii i Nowej Zelandii, Japonii. Znajduje zastosowanie w medycynie, rolnictwie, a także jako roślina ozdobna.
Erva-de-são-joão ou hipérico (português brasileiro) ou hipericão (português europeu) (Hypericum perforatum) é uma planta herbácea perene, pertencente à família Hypericaceae e antes incluída nas famílias Guttiferae ou Clusiaceae e largamente distribuída na Europa, Ásia, norte da África e aclimatada nos Estados Unidos.
É um pequeno arbusto, de porte erecto, atingindo cerca de 1 metro de altura. As folhas são opostas, sésseis, dotadas de glândulas translúcidas, que podem ser observadas colocando-se a folha contra a luz. As flores são numerosas, persistentes, de coloração amarela e possuem pequenos pontos pretos ao longo das margens das flores que contêm elevadas concentrações do pigmento vermelho hipericina.
Durante séculos a Hypericum perforatum foi muito utilizada, inicialmente pela sua capacidade de cicatrizar feridas, úlceras de pele e queimaduras. Considerada capaz de afastar maus espíritos, foi utilizada no tratamento de inúmeras doenças mentais. Actualmente a planta não é muito usada para estes propósitos, mas sim, largamente testada na actividade antidepressiva contra estados depressivos suaves a moderados, ansiedade, insónia, dores nevrálgicas e, ainda, actividades antiviral, antibacteriana e fotossensibilizadora.
Costuma ser prescrita em cápsulas de 100 mg a 300 mg, como um antidepressivo e/ou calmante natural.
Em alguns países da Europa, como na Alemanha, é mais prescrita contra a distimia e depressão clínica leve ou moderada do que a fluoxetina (antidepressivo químico mais usado mundialmente), em até dez vezes mais.
Pode ser encontrada para a venda em farmácias de manipulação, fábricas de fitoterápicos, ou em casas de produtos naturais, nesse último local sendo geralmente vendida em pó.
Pelos seus benefícios bastante comprovados e por não induzir dependência química medicamentosa, tem sido frequentemente indicada como medicamento de transição na descontinuação de fármacos como, por exemplo, clozapina, fluoxetina, olanzapina, entre outros. Também é medicamento de primeira escolha em muitos quadros clínicos. Seu uso, nessas circunstâncias, permite prevenir ou, quando necessário, curar a drogadição medicamentosa.
A utilização da erva de São João ou Hipericão produz reações adversas quando utilizado em simultâneo com inibidores da recaptação da serotonina (por exemplo paroxetina). Também é contraindicada a utilização simultânea com antirretrovirais, anticoncepcionais e a varfarina. [1][ligação inativa]
Também é contraindicada a sua utilização simultânea com antiepiléticos contendo Carbamazepina.
Erva-de-são-joão ou hipérico (português brasileiro) ou hipericão (português europeu) (Hypericum perforatum) é uma planta herbácea perene, pertencente à família Hypericaceae e antes incluída nas famílias Guttiferae ou Clusiaceae e largamente distribuída na Europa, Ásia, norte da África e aclimatada nos Estados Unidos.
Sunătoarea (Hypericum perforatum) (alte denumiri: pojarniță, regionalisme: drobișor, fălcățea, harnică, închegătoare)[1] este o plantă erbacee, perenă, cu tulpină dreaptă, ramificată în partea superioară, ușor lemnoasă în partea de jos, prevăzută de-a lungul ei cu două muchii, glabră și înaltă până la 1m. Frunzele, dispuse opus, sunt sesile, oval-eliptice, glabre și conțin numeroase pungi secretoare, dând impresia că prezintă puncte translucide (când sunt examinate prin transparență), de unde și denumirea de "perforatum" dată acestei specii. Florile sunt grupate în vârful tulpinii și ramurilor, sunt hermafrodite, pentamere; periantul este format din 5 sepale și 5 petale de culoare galben-aurie, iar androceul din stamine numeroase. Înflorește din iunie până în septembrie. Fructul este o capsulă ovală.
Produsul vegetal folosit în produsele terapeutice este reprezentat de părțile terminale (de 20–30 cm) înflorite (Herba Hyperici). Florile de sunătoare se culeg în zile uscate și însorite, din iunie și până în septembrie, prin tăiere cu foarfeca. Se usucă la umbră, în loc bine aerisit, întinse în strat subțire, pe hârtie sau pânză. După uscare, se păstrează în pungi de hârtie ori săculeți de pânză în locuri uscate și întunecate.
Ca și principii active, sunătoarea este bogată în derivați antracenici (hipericină, pseudohipericină), uleiuri volatil, flavonozide având ca aglicon hiperina, acizii cafeic și clorogenic, taninuri.
Acțiune farmacologică: datorită hipericinei și pseudohipericinei, uleiului volatil și taninurilor, produsul are acțiune antiseptică, astringentă și cicatrizantă. Flavonozidele sunt răspunzătoare de acțiunea vasodilatatoare și hipotensivă. Acizii clorogenic și cafeic explică proprietățile antiinflamatoare și colagoge ale plantei.
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WikiProiect Sunătoarea (Hypericum perforatum) (alte denumiri: pojarniță, regionalisme: drobișor, fălcățea, harnică, închegătoare) este o plantă erbacee, perenă, cu tulpină dreaptă, ramificată în partea superioară, ușor lemnoasă în partea de jos, prevăzută de-a lungul ei cu două muchii, glabră și înaltă până la 1m. Frunzele, dispuse opus, sunt sesile, oval-eliptice, glabre și conțin numeroase pungi secretoare, dând impresia că prezintă puncte translucide (când sunt examinate prin transparență), de unde și denumirea de "perforatum" dată acestei specii. Florile sunt grupate în vârful tulpinii și ramurilor, sunt hermafrodite, pentamere; periantul este format din 5 sepale și 5 petale de culoare galben-aurie, iar androceul din stamine numeroase. Înflorește din iunie până în septembrie. Fructul este o capsulă ovală.
Produsul vegetal folosit în produsele terapeutice este reprezentat de părțile terminale (de 20–30 cm) înflorite (Herba Hyperici). Florile de sunătoare se culeg în zile uscate și însorite, din iunie și până în septembrie, prin tăiere cu foarfeca. Se usucă la umbră, în loc bine aerisit, întinse în strat subțire, pe hârtie sau pânză. După uscare, se păstrează în pungi de hârtie ori săculeți de pânză în locuri uscate și întunecate.
Šentjánževka (znanstveno ime Hypericum perforatum) je trajna zelika, ki zraste do višine 70 cm. Cvetovi, ki največ cvetijo julija, se v ljudski medicini uporabljajo za zdravljenje trebušnih (krčev in vnetij), opeklin in živčnih bolezni. Klinično je dobro dokazano njeno antidepresivno delovanje. V Nemčiji se zdravila s šentjanževko dobi tudi na recept in so v skupini antidepresivov najpogosteje predpisovana zdravila. Izvleček šentjanževke vsebuje vrsto različnih snovi, kot so: hipericin, psevdohipericin, hiperforin, flavonoidi, fenolne kisline.
Šentjanževka v telesu močno poveča aktivnost encimov, ki so odgovorni za razgradnjo zdravil. Ob sočasnem jemanju šentjanževke in drugih zdravil, je učinek teh zdravil zmanjšan.
Äkta johannesört (Hypericum perforatum)[1] är en johannesörtsväxtart. Äkta johannesört ingår i släktet johannesörter, och familjen johannesörtsväxter.[1][2]
Äkta johannesört är en flerårig växt med gula blommor. Den kan bli upp till 7 decimeter hög. Äkta johannesört blommar under högsommaren och hösten, från juli till september. Blommorna sitter i ganska yviga knippen i stjälkens topp.[3]
Bladen hos äkta johannesört är motsatta, elliptiskt formade och är tätt punkterade av genomskinliga körtelprickar. Foderbladen är spetsiga och både de och kronbladen har vanligen oskaftade svarta körtlar.[3]
Karakteristiskt för äkta johannesört är att stjälken är försett med två längsgående åsar. Förväxlingsarten fyrkantig johannesört, (Hypericum maculatum), har fyra sådana åsar, varför stjälken hos den får fyrkantig genomskärning.[3]
Hypericum i det vetenskapliga namnet kan översättas med "över bild", vilket kan härledas från grekiskans hyper, med betydelsen "över", och eikon, med betydelsen "bild". Denna benämning kommer därav att man i gamla tider trodde sig kunna fördriva onda andar från det som bilden föreställde genom att hänga några kvistar av örter från Hypericum-släktet ovanför bilden.
Andefördrivningsförmågan går igen i en gammal benämning på johannesört, nämligen Fuga Dæmonum, där latinska fuga betyder "flykt". Fuga Dæmonum kan alltså översättas med "de onda andarnas (demonernas) flykt".
Denna tro har givit upphov till de folkliga översättningarna satansflykt och djävulsflykt som benämning på johannesört.
Perforatum kommer från att bladen ser ut att ha blivit perforerade. Hålen är små, men syns om man håller upp bladet mot ljuset. Det är på så sätt man ser om man har plockat den äkta johannesörten eller man har plockat den fyrkantiga johannesörten. Den fyrkantiga johannesörten har inga oljekörtlar i bladen och är inte heller perforerade. Vill man göra en brygd av johannesört så måste man för att få den blodröda färgen förvissa sig om att det är äkta johannesört. Den äkta johannesörten och den fyrkantiga johannesörten (som inte är verksam fysiologiskt) växer oftast på samma ställen och tätt intill varandra.
Ett gammalt namn för johannesört är mansblod/mannablod med anledning av att krossade blomknoppar avger en blodröd saft. Enligt sägnen så växte det upp en blomma på marken där Johannes Döparen halshöggs och blodet droppade ner. Därav också blommans namn.
På svenska har Hypericum perforatum slagits samman och förvanskats till hirkum pirkum som benämning på brännvin kryddat med johannesört. Uttrycket att vara pirum, det vill säga vara berusad, som beteckning på den som förtärt denna dryck i övermått ligger bakom johannesörtens alternativa namn randpirk – "Hypericum med det randiga strået".
Namnet Johannes i olika variationer (John, Hannes, Hans etc) går igen även i denna växts namn på många andra språk än svenska. En osäker förklaring är eventuellt en koppling till Johannes Döparens dag, som är midsommardagen i hela den kristna världen, en dag då det vore lämpligt att skörda de hälsobringande blommorna. Kan också vara en teori till blommans namn.[4]
På vissa håll har namnet johannesört använts även om slåttergubbe (Arnica montana) och älggräs (Filipendula ulmaria), men dessa arter är inte alls släkt med Hypericum perforatum.
Arten delas in i följande underarter:[1]
Planta
Körtlar i bladen.
Småplantor
Frukt
Blomma
Wikimedia Commons har media som rör Hypericum perforatum.
Wikispecies har information om Hypericum perforatum.
Äkta johannesört (Hypericum perforatum) är en johannesörtsväxtart. Äkta johannesört ingår i släktet johannesörter, och familjen johannesörtsväxter.
Bu maddenin sonunda bir kaynak listesi olmasına rağmen, metin içi kaynaklar yeterince veya hiç kullanılmadığı için, bazı bilgilerin kaynağı belirsizdir. Lütfen maddedeki kaynakları uygun biçimde metin içinde yerleştirerek bu maddenin geliştirilmesine katkıda bulununuz. Sarı kantaron (Hypericum perforatum), Kılıç otu, Mayasıl otu ve Koyunkıran olarak da bilinir, sarı kantarongiller (Hypericaceae) familyasına dahil bir bitki türü.
Esas olarak dünyanın birçok yerinde bulunan bir bitkidir. Avrupa'da tarla, yol ve orman kenarlarında kendiliğinden yetişen bitki Kuzey Amerika'ya da uyum sağlamış ve doğal olarak kırlarda yetişmeye başlamıştır.
Çiçeklenme döneminde bitkinin çiçek ve tomurcukları veya tüm toprak üstü kısımları toplanarak hemen kurutulduktan sonra kullanılır. Avrupa'da uzun süredir ruhsal bozuklukların tedavisinde kullanılan Amerika'da da oldukça popüler bir bitki türüdür. Geçmiş tarihlerde sarı çiçekleri toplanarak güneş ışığı alan bir yerde zeytinyağında bekletilirdi. Bu yağ kırmızı renk aldıktan sonra oluşan merhem yara iyileştirici olarak ve özellikle de yanık yaraları ile yatalak hastalarda oluşan yaralarda tedavi edici olarak kullanılırdı. Bitki eski Yunan ve Roma medeniyetleri zamanında kötü büyülere karşı koruyucu olarak ünlenmişti.
[1] Baytop T. Geçmişte ve Günümüzde Türkiye'de Bitkilerle Tedavi, Nobel Kitabevi, İstanbul, 1999.
[2] Ernst E. Hypericum: The Genus Hypericum, Taylor & Francis, London, 2003
[3] Öztürk Y. Testing the antidepressive effects on animal models with the special reference of Hypericum. Pharmacopsychiatry 30(Suppl), 125-128, 1997.
Sarı kantaron (Hypericum perforatum), Kılıç otu, Mayasıl otu ve Koyunkıran olarak da bilinir, sarı kantarongiller (Hypericaceae) familyasına dahil bir bitki türü.
Esas olarak dünyanın birçok yerinde bulunan bir bitkidir. Avrupa'da tarla, yol ve orman kenarlarında kendiliğinden yetişen bitki Kuzey Amerika'ya da uyum sağlamış ve doğal olarak kırlarda yetişmeye başlamıştır.
Стебло пряме, голе, вгорі гіллясте, 30-60 см заввишки. Міжвузля округлі або з двома гранями, щільні. Листки супротивні, сидячі, овальні, видовжено-яйцеподібні або видовжені, тупуваті, цілокраї, з численними залозками. Квітки правильні, зібрані в щитоподібну волоть або нещільну китицю. Чашечка з п'яти зрослих при основі ланцетних, загострених, гладеньких по краю чашолистків. Віночок п'ятичленний, жовтий, пелюстки з численними чорно-бурими або фіолетовими крапками. Тичинок багато, маточка одна з верхньою зав'яззю і трьома-п'ятьма стовпчиками. Плід — багатонасінна тригранна коробочка.
Росте у мішаних лісах, на галявинах, лісосіках, серед чагарників. Тіньовитривала рослина. Цвіте у червні-серпні.
Поширений по всій території України. Промислова заготівля можлива у Волинській, Житомирській, Київській, Чернігівській, Львівській, Тернопільській, Хмельницькій, Сумській, Полтавській, Кіровоградській, Черкаській, Івано-Франківській, Чернівецькій, Закарпатській областях. Запаси сировини значні.
Лікарська, фітонцидна, ефіроолійна, танідоносна, харчова, фарбувальна, медоносна, отруйна рослина.
У науковій медицині використовують квітучі верхівки пагонів — Herba Нурегісі як в'яжучий, протизапальний і тонізуючий засіб при кровохарканні, кашлі, проносах, колітах, хворобах печінки, для укріплення ясен. Лікарські властивості звіробою пов'язані з його досить складним хімічним складом. Трава звіробою містить дубильні, смолисті, фарбувальні речовини, флавоноїди, каротин, вітамін С, глюкозид гіперін, холін, сапоніни тощо. Із звіробою звичайного виробляють антибактеріальні препарати іманін і новоіманін, якими лікують гнійні рани, тяжкі опіки, гострі катари дихальних шляхів. Новоіманін використовують для боротьби з бактеріозами овочевих рослин і проти вірусної мозаїки тютюну. Звіробоєм лікують стоматити, гайморити, фарингіти, молочницю у дітей.
У народній медицині звіробій дуже популярний лікувальний засіб, який застосовується при багатьох хворобах: проносах, шлунково-кишкових захворюваннях, хворобах дихальних шляхів, як тонізуючий засіб при серцево-судинних захворюваннях, як кровоспинний — при маткових кровотечах, хворобах печінки, нирок і як глистогінний засіб, при невралгіях, істерії, безсонні, епілепсії, паралічах.
Відваром трави миють дітей при діатезах, туберкульозі шкіри, при висипах, наривах, а при хворобах молочних залоз прикладають компреси. Корені рослини застосовують при шигельозі та туберкульозі кісток.
У народі існує популярний рецепт звіробійної олії, яку радять готувати таким чином: узяти одну частину свіжих квіток звіробою і залити 10 частинами лляної чи соняшникової олії. Настоювати протягом 2 тижнів поки олія не почервоніє. Можна готувати за іншим рецептом (тоді настій буде концентрованішим): 1 частина звіробою — 2 частини олії. Тут добре використати олію маслинову, рафіновану кукурудзяну чи соняшникову, настоювати 3 тижні.
Звіробійну олію використовують для лікування ран, виразок, наривів, розпушених ясен, уражень слизової оболонки рота. Усередину вживають для зміцнення серцевого м'яза [1].
Деякі травознаї, як Наталя Земна, не рекомендують вживати звіробій протягом тривалого часу, особливо чоловікам (не більше 7 днів на рік).
У гомеопатії використовують есенцію з свіжої квітучої рослини.
У ветеринарії для лікування ран застосовують емульсію з настою трави, виготовлену на вазеліновій олії. Фітонцидні властивості звіробою зумовлені наявністю в ньому ефірних олій (0,09-0,114 %), до складу яких входять пінен, мірцен, цінеол. Олію з звіробою використовують у парфумерії, для лікування ран і опіків, виразок шлунка та дванадцятипалої кишки.
В усіх частинах рослини є таніди (до 7,5 %), тому її застосовують для дублення шкур, надаючи їм еластичності, щільності та приємного забарвлення.
У харчовій промисловості звіробій використовують для приготування гірких горілок і настоїв, а листки — як сурогат чаю. Квітки містять барвник гіперицин, з різними протравами вони дають жовту, зелену, червону, рожеву фарби,, придатні для фарбування шерсті. Звіробій звичайний — добрий пилконос.
У траві звіробою знайдені сапоніни. При з'їданні великої кількості його вівці, коні й велика рогата худоба отруюються. Цікаво відзначити, що отруюються, як правило, тварини з білою шерстю. Звіробій викликає розвиток дерматитів у білошерстих тварин, сверблячку, параліч аборти. Інші види звіробою в науковій медицині не використовуються і домішки їх до сировини з трави звіробою звичайного небажані.
Збирають верхівки рослин під час цвітіння, зрізуючи їх ножами або серпами (довжина пагонів 25-30 см) без грубих безлистих частин. Сировину сушать на горищах, під залізним дахом або в сушарках при температурі до 40°, розтираючи тонким шаром на папері, тканині або решетах і часто помішуючи. Висушену траву обмолочують і відділяють на решетах стебла. Суху сировину пакують у тюки по 50 або 100 кг. Зберігають у сухих, добре провітрюваних приміщеннях. Строк зберігання три роки.
Hypericum perforatum, (tiếng Anh: được gọi phổ biến là perforate St John's-wort, common Saint John's wort và St John's wort),[1] là một loài thực vật có hoa trong Họ Ban. Tên gọi "St John's wort" có thể được sử dụng để chỉ mọi loài thuộc Chi Ban. Vì vậy, Hypericum perforatum đôi khi được gọi là "common St John's wort" hay"perforate St John's wort" để dễ phân biệt. Nó được cho là một loại thảo mộc dược liệu có hoạt tính chống trầm cảm, mặc dù bằng chứng lâm sàng cho thấy những tác dụng của nó trong việc điều trị này còn bị hạn chế.
Thành phần hoạt tính dược lý chủ yếu của St John's wort là hyperforin, một chất ức chế arachidonate 5-lipoxygenase và chất ức chế COX-1 trong ống nghiệm.
Hypericum perforatum có nguồn gốc từ các nước ở châu Âu và châu Á [2] nhưng đã lan rộng đến các vùng ôn đới trên toàn thế giới như một loài cỏ dại dễ dàng lan ra mọi nơi.
Tên gọi chung "St John's wort" xuất phát từ hoa và thu hoạch truyền thống vào ngày St John's Day, ngày 24 tháng 6. Tên Hyperocum có nguồn gốc từ các từ Hy Lạp hyper (ở trên) và eikon (ảnh), liên quan đến truyền thống treo trên cây các biểu tượng tôn giáo trong nhà trong ngày St John's, để tránh khỏi cái ác.
St John's wort là một loại cây lâu năm thân thảo với những thân rễ to lớn. Thân của nó được dựng lên, phân nhánh ở phần trên và có thể cao tới 1 m. Nó có các lá đối diện, cuống rạc, hẹp, thuôn dài 1–2 cm. Các lá có màu vàng xanh, với các chấm mờ rải rác của mô tuyến[3]. Các dấu chấm là dễ thấy khi được đưa ra với ánh sáng. Những bông hoa dài tới 2,5 cm, có năm cánh hoa, và có màu vàng sáng với những chấm đen nên cũng rất dễ nhận ra. Những bông hoa xuất hiện ở những chất tụ tán rộng ở cuối nhánh trên, giữa cuối mùa xuân và đầu đến giữa mùa hè. Các đường gân dễ thấy với các chấm tuyến màu đen[4]:339. Có rất nhiều nhị hoa, được kết hợp lại với nhau tạo thành ba chùm chính.
Khi nụ hoa (không phải là hoa) hoặc vỏ hạt được nghiền nát, một chất lỏng màu đỏ / tím được tạo ra[5].
Nó phát triển mạnh ở các khu vực có tính chất mưa mùa đông hoặc mùa hè chiếm ưu thế; tuy nhiên, sự phân bố bị hạn chế bởi nhiệt độ quá thấp đối với sự nảy mầm của hạt hoặc sự sinh tồn của cây con. Độ cao lớn hơn 1500 m, lượng mưa nhỏ hơn 500 mm và nhiệt độ trung bình hàng ngày lớn hơn 24 °C được coi là ngưỡng giới hạn. Tùy thuộc vào điều kiện môi trường và khí hậu, và tuổi hoa, St John's wort sẽ thay đổi hình thức tăng trưởng và thói quen để thúc đẩy sự sống còn. Mưa mùa hè đặc biệt hiệu quả trong việc cho phép cây phát triển.
Các hạt giống có thể tồn tại trong nhiều thập kỷ trong đất, nảy mầm sau sự xáo trộn.
St. John's Wort phổ biến từ lâu đã được sử dụng trong dược thảo và y học dân gian[6]. Nó được cho là có tính chất y học cổ đại và là một thành phần tiêu chuẩn của các chất kích thích, từ Mithridate của Aulus Cornelius Celsus 'De Medicina (khoảng 30 CE) đến Venice treacle của d'Amsterdammer Apotheek năm 1686. Hypericum perforatum là một loài phổ biến và được trồng nhiều để sử dụng trong thảo dược và y học cổ truyền [7] .
Chất chiết xuất từ da dầu màu đỏ của H. perforatum có thể giúp chữa lành vết thương [6][8] Both hypericin and hyperforin are under study for their potential antibiotic properties.[9]
. Cả hypericin và hyperforin đều đang được nghiên cứu cho các tính chất kháng sinh tiềm năng của chúng.
Wort St. John có thể ảnh hưởng đến tác dụng của nhiều loại thuốc theo toa, bao gồm thuốc ngừa thai, cyclosporin, digoxin, thuốc HIV, thuốc ung thư bao gồm irinotecan và warfarin. Kết hợp cả thuốc chống trầm cảm và St John's wort có thể làm tăng nồng độ serotonin gây hội chứng serotonin[10]. Nó không nên được kết hợp với thuốc tim, ranolazine[11] Combining estrogen containing oral contraceptives with St John's wort can lead to decreased efficacy of the contraceptive and eventually unplanned pregnancies.[12]. Kết hợp estrogen có chứa trong thuốc tránh thai khi uống với St John's wort có thể dẫn đến giảm hiệu quả của các biện pháp tránh thai và cuối cùng có thể có thai ngoài ý muốn. Sử dụng St. John's wort làm giảm nhẹ tình trạng rối loạn lưỡng cực.
Một hóa chất thành phần chính, hyperforin, có thể hữu ích trong điều trị nghiện rượu, mặc dù liều lượng, an toàn và hiệu quả chưa được nghiên cứu. Hyperforin cũng đã hiển thị các tính chất kháng khuẩn chống lại vi khuẩn Gram dương, mặc dù liều lượng, an toàn và hiệu quả chưa được nghiên cứu. Thuốc thảo dược cũng đã sử dụng chất chiết xuất từ chất lipophilic từ St John's wort để làm thuốc bôi cho vết thương, trầy xước, bỏng và đau cơ. yperforin có thể hữu ích trong điều trị các vết thương nhiễm trùng và các bệnh viêm da. Để đối phó với sự kết hợp của hyperforin vào một loại dầu tắm mới, một nghiên cứu để đánh giá khả năng kích thích da tiềm ẩn đã được tiến hành, điều này đã cho thấy khả năng chịu đựng tốt của làn da của St John's wort.
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|df= (trợ giúp) Hypericum perforatum, (tiếng Anh: được gọi phổ biến là perforate St John's-wort, common Saint John's wort và St John's wort), là một loài thực vật có hoa trong Họ Ban. Tên gọi "St John's wort" có thể được sử dụng để chỉ mọi loài thuộc Chi Ban. Vì vậy, Hypericum perforatum đôi khi được gọi là "common St John's wort" hay"perforate St John's wort" để dễ phân biệt. Nó được cho là một loại thảo mộc dược liệu có hoạt tính chống trầm cảm, mặc dù bằng chứng lâm sàng cho thấy những tác dụng của nó trong việc điều trị này còn bị hạn chế.
Thành phần hoạt tính dược lý chủ yếu của St John's wort là hyperforin, một chất ức chế arachidonate 5-lipoxygenase và chất ức chế COX-1 trong ống nghiệm.
Hypericum perforatum L. (1753)
Зверобо́й продыря́вленный, или Зверобо́й обыкнове́нный (лат. Hypéricum perforátum) — многолетнее травянистое растение; вид рода Зверобой (Hypericum) семейства Зверобойные (Hypericaceae), типовой вид этого рода[2]. Ранее род Зверобой обычно рассматривали в составе семейства Клузиевые (Clusiaceae).
Одно из наиболее используемых лекарственных растений; используется также в пищевой промышленности.
Народные названия растения — заячья кровь, зверобой дырявый, зверобой жёлтый, зверобойник, красная травица, кровавец, кровца, хворобой[3], зелье светоянское[4][5].
Растёт зверобой повсеместно, местами образует целые заросли вдоль опушек хвойных лесов, по сухим лугам, лесным солнечным полянам. Встречается как сорняк вдоль лесных дорог и по окраинам полей.
В природных сообществах урожайность надземной массы — 0,1—15 ц/га, в опытных посевах на второй год — 15—25, на третий — 30—40 ц/га[6].
Широко распространён в Евразии — от Атлантического побережья до Сибири, Монголии и Китая. Встречается в Северной Африке, на Канарских и Азорских островах. Как натурализовавшееся растение встречается в Австралии, Новой Зеландии, Японии, Южной и Северной Америке[7].
Растение с тонким, сильным корневищем, от которого ежегодно вырастает несколько гладких двугранных ветвистых стеблей высотой до 40—80 см[8].
Стебель — прямостоячий, зелёного цвета, затем становится красновато-бурого цвета; на гладкой поверхности выделяются две продольные линии. Характерны секреторные вместилища с тёмным содержимым.
Листья супротивные, сидячие, продолговато-яйцевидные или эллиптические, длиной до 3 см, шириной до 1,5 см[8], цельнокрайние с многочисленными светлыми и тёмными желёзками (отсюда и название — продырявленный).
Соцветие — верхушечный кистевидно-щитковидный тирс. Цветки правильные, до 2 см в диаметре[8], с двойным пятичленным околоцветником. Чашечка глубоко-раздельная, остаётся при плоде, свободные части ланцетные с редкими чёрными желёзками. Лепестки свободные, золотисто-жёлтые, продолговато-эллиптические, на верхушке косо срезанные, с желёзками, которые по краю листа тёмные, а на остальной поверхности — светлые. Многочисленные тычинки срослись в три пучка. Гинецей ценокарпный, столбики отогнутые, рыльца с красными сосочками, завязь трёхгнездная, у её основания — железистые стаминодии. Цветёт зверобой с июня по август в течение 25—30 дней.
Формула цветка: 
∗ C a ( 5 ) C o 5 A ( ∞ ) + ( ∞ ) + ( ∞ ) G ( 3 _ ) {displaystyle mathrm {ast ;Ca_{(5)};Co_{5};A_{(infty )+(infty )+(infty )};G_{({underline {3}})}} } 
Пыльцевые зёрна трёхбороздно-оровые или трёхбороздно-оровидные, шаровидной или эллипсоидальной формы. Длина полярной оси 13,6—17,7 мкм, экваториальный диаметр 13,6—17 мкм. В очертании с полюса почти округло-трёхлопастные, с экватора — округлые или широко-эллиптические. Борозды шириной 3—5 мкм, с ровными краями и заострёнными или притуплёнными концами, почти сходящимися у полюсов. Оры округлые или экваториально вытянутые, часто слабо заметны. Мембрана борозд и ор мелкозернистая. Экзина толщиной 1—1,3 мкм. Ширина мезокольпиума 2—3 мкм. Скульптура мелкосетчатая, ячейки мелкие, округло-угловатые. Стерженьки тонкие, с маленькими, округлыми головками; подстилающий и покровный слои тонкие. Цвет пыльцы тёмно-жёлтый[8].
Плод — трёхгранная многосемянная коробочка с сетчатой поверхностью, открывается створками.
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Зверобой как лекарственное растение известен с давних пор.
В качестве лекарственного сырья используют траву зверобоя (лат. Herba Hyperici) — собранные в фазе цветения побеги дикорастущего или культивируемого зверобоя продырявленного[10]. Трава зверобоя содержит дубильные вещества, эфирное масло, β-ситостерин, тритерпеновые сапонины, витамины С, E, флавоноиды (гиперозид, рутин), антрахиноны, макро- и микроэлементы и другие биологически активные вещества, красящее вещество гиперицин.
Отвар, настой, настойка зверобоя используются как вяжущее и антисептическое средство при желудочно-кишечных заболеваниях (гастриты, язвенная болезнь желудка и двенадцатиперстной кишки, энтероколиты, поносы, язвенный колит, геморрой), печени и жёлчного пузыря (дискинезия жёлчного пузыря, холецистит, жёлчнокаменная болезнь, острый и хронический гепатит), для полоскания при воспалительных заболеваниях слизистой оболочки рта и зева (острые тонзиллиты (ангины) и хронические тонзиллиты, гингивиты, стоматиты). Применяется при астенических состояниях, неврозах и неврастениях, судорогах, головных болях, бессоннице, миокардитах и эндокардитах, гломерулонефритах, пиелонефритах, циститах и воспалениях предстательной железы, артритах, радикулитах. Им лечат также многие женские заболевания (воспаления придатков, аменореи, обильные менструации, бели), а также аллергический диатез у детей. Настойка и отвар зверобоя оказывают положительное действие при туберкулёзе лёгких[11].
В составе зверобоя имеется аментофлавон — неселективный блокатор (антагонист) опиоидных каппа-рецепторов[12], а также бензодиазепинового сегмента ГАМКА-рецепторов[13], чем в некоторой степени объясняется антидепрессивное и антипохмельное воздействие на психику. Другой компонент, гиперфорин является ингибитором обратного захвата моноаминов, в том числе серотонина и дофамина[14], что также облегчает депрессию. Гиперицин селективно ингибирует фермент дофамин-бета-гидроксилазу, что повышает уровень дофамина.
Экстракты зверобоя применяются при лечении депрессии[15][16]. Эффективность препаратов экстракта зверобоя сопоставима с эффективностью широко применяемых синтетических антидепрессантов, что подтверждено большим количеством клинических испытаний и результатами нескольких мета-анализов. При этом по показателю переносимости экстракт зверобоя достоверно превосходит синтетические препараты: его побочные эффекты развивались значительно реже и имели менее тяжёлый характер[16].
По данным кохрейновского обзора 29 исследований, в которых участвовали 5489 пациентов, при лёгкой и умеренной депрессии препараты зверобоя оказались не менее эффективными, чем стандартные (синтезированные) антидепрессанты, и при этом вызывали меньше побочных эффектов[15]. Сходные результаты показал и систематический обзор 35 исследований, включивших 6993 пациентов, данные которого были опубликованы в Systematic Reviews (англ.)русск. (однако авторы отмечали, что в исследованиях было недостаточно данных о неблагоприятных побочных реакциях, а также о том, эффективен ли зверобой при тяжёлой депрессии)[17].
Зверобой также может применяться при тревожных расстройствах, его эффективность при этих расстройствах продемонстрирована в ряде небольших рандомизированных испытаний. В многоцентровом рандомизированном плацебо-контролируемом исследовании с участием 151 амбулаторного пациента эффективность Hypericum perforatum подтверждена и при соматоформных расстройствах[16].
Препарат «Новоиманин» применяют наружно при лечении абсцессов, флегмон, инфицированных ран[10].
В народной медицине зверобой применяют при лечении подагры, суставного ревматизма, туберкулёза лёгких, ишиаса. Спиртовую настойку принимают внутрь при ревматических заболеваниях, измельчённые листья прикладывают к ранам для скорейшего заживления. В Болгарии наземную часть растения используют в виде отвара как противовоспалительное и вяжущее средство при заболеваниях органов пищеварения, печени, жёлчного пузыря, в Польше — при лечении неврастении, невралгии, бессонницы, головной боли, болезнях желудка, как кровоостанавливающее и ранозаживляющее средство. Во Франции масло зверобоя применяют при лечении ран и ожогов, как мочегонное, а также как средство, стимулирующее деятельность сердца и возобновление тканей[11].
К побочным эффектам зверобоя относятся фотосенсибилизация, а также развитие маниакальных состояний у пациентов, страдающих биполярной депрессией[18] (развитие мании у этих пациентов возможно и при применении обычных, рецептурных антидепрессантов). Обладая стимулирующим эффектом, зверобой способен усиливать чувство тревоги у некоторых людей[19]. Возможны, кроме того, желудочно-кишечные побочные действия, аллергические реакции[20], усталость, беспокойство, спутанность сознания[18].
Следует быть предельно аккуратным, применяя зверобой с другими лекарственными средствами, в первую очередь с иммуносупрессантами. Являясь мощным катализатором CYP-энзимов, зверобой ускоряет выведение медикаментов из организма, тем самым снижая их терапевтический эффект, что в некоторых случаях приводило, например, к отторжению пересаженного органа[21]. Также он может снижать эффективность противозачаточных таблеток[19]. Препараты зверобоя не следует принимать одновременно с такими антидепрессантами, как селективные ингибиторы обратного захвата серотонина и ингибиторы моноаминоксидазы[22]:77[23]: это сочетание может привести к тяжёлым побочным реакциям, в частности к развитию серотонинового синдрома[20].
По данным исследования, проводившегося в Канаде (2013), многие препараты, созданные на основе растительных компонентов, в том числе и один из препаратов на основе зверобоя, представляют собой риск для здоровья потребителей из-за нежелательных примесей и других загрязнителей. В числе веществ, не отмеченных в документах к продукции, обнаружились вещества с известными токсическими характеристиками и побочными эффектами — например, засушенный зверобой оказался смешан с кассией остролистной, обладающей выраженным слабительным действием. Длительный приём кассии остролистной наносит вред печени, желудочно-кишечной и иммунной системе[24].
Умеренно посещается пчёлами для сбора пыльцы. Цветки выделяют немного нектара, в основном в тёплую влажную погоду[8].
Зверобой продырявленный в России заваривали как чай и пили при всяких недомоганиях, да и просто как приятный напиток[6].
Цветущие побеги зверобоя используют для ароматизации водок и горьких настоек («зверобой», «ерофеич» и другие)[6].
Олиственные побеги и цветки используют для окрашивания шерсти и тканей в красный цвет[6].
Надземные части употребляют для дубления кож[6].
Зверобо́й продыря́вленный, или Зверобо́й обыкнове́нный (лат. Hypéricum perforátum) — многолетнее травянистое растение; вид рода Зверобой (Hypericum) семейства Зверобойные (Hypericaceae), типовой вид этого рода. Ранее род Зверобой обычно рассматривали в составе семейства Клузиевые (Clusiaceae).
Одно из наиболее используемых лекарственных растений; используется также в пищевой промышленности.
貫葉連翹（學名：Hypericum perforatum）， 又名贯叶金絲桃、聖約翰草（St John's wort），金丝桃科金絲桃屬植物，是歐美的常用草藥，主要用於婦女調經，亦有寧神、平衡情緒的作用，臨床上發現對抑鬱症患者有療效[1]。
多年生草木，高可达1m左右。茎直立，多分枝，枝皆腋生，茎两侧各有纵棱1条。单叶对生，长椭圆形或披针形，长1~3cm，基部无柄，有时抱茎，散布透明腺点，叶缘有黑色腺点。聚伞花序顶生；花较大，黄色，萼片5；花瓣5；雄蕊多数，组成3束，花瓣边缘和花药均有黑色腺点，子房上位，1室，花柱3裂。蒴果长圆形，具泡状小突起，开裂。种子圆筒形。花期6~7月，果期9~10月。
为植物贯叶金丝桃Hypericum perforatum L.的干燥地上部分，主产于江西、四川、陕西。[2]
性寒，味辛。能疏肝解郁，清热利湿，消肿通乳。用于肝气郁结，情志不畅，心胸郁闷，关节肿痛，乳痈，乳少。用量2~3g。
夏、秋二季开花时采割，阴干或低温烘干。
含有二蒽酮类，其主要成分为金丝桃素、伪金丝桃素、原金丝桃素等。还含有贯叶金丝桃素、加贯叶金丝桃素等间苯三酚衍生物，这是贯叶连翘的特征性成分，也是其抗抑郁作用的主要有效成分。尚含金丝桃苷、山奈酚等黄酮类等。
抗抑郁、抗焦虑、抗感染作用。
貫葉連翹藥力強大，可能與其他西藥物互相牴觸，例如降低避孕藥的療效，故服用前應先諮詢醫生意見。但其副作用亦較西藥為低。常見副作用包括腸胃不適、頭暈、混亂、疲倦、鎮定、口乾、煩躁及頭痛。其也可能導致光照性皮炎。對躁鬱症患者可能會誘發躁症而精神分裂症患者可能會惡化其幻覺。
貫葉連翹（學名：Hypericum perforatum）， 又名贯叶金絲桃、聖約翰草（St John's wort），金丝桃科金絲桃屬植物，是歐美的常用草藥，主要用於婦女調經，亦有寧神、平衡情緒的作用，臨床上發現對抑鬱症患者有療效。
セイヨウオトギリ（西洋弟切、学名：Hypericum perforatum、英語名：St. John's wort、Klamath weed、Goat weed）は、オトギリソウ科オトギリソウ属の多年草である。英語におけるセント・ジョーンズ・ワート (St. John's wort) は、本種の一般名だが、様々な修飾語とともに、オトギリソウ属の他種を指すこともあり、英語ではそれらと区別するために、本種を Common St. John's wort と呼ぶ場合もある。
セイヨウオトギリは黄色い花を咲かせる根茎性の多年草であり、ヨーロッパに自生し、後にアメリカへも伝播し多くの草地で野生化している。 聖ヨハネの日（6月24日）の頃までに花が咲き、伝統的にその日に収穫されたためその名が付いた。地上部全体が刈られ乾燥させられハーブティーとして用いられる。 そのハーブティーは若干苦いものの嗜好品としてまたその薬理的性質のため長い間愛好されてきた。学名のperforatumは光にかざすと見える葉にある小さな窓（油点）に由来する。
セイヨウオトギリが商業的に栽培されている地域はあるものの20以上の国では毒草としてリストされている。家畜による摂取は 光過敏感反応、中枢神経抑圧、流産または最悪死をもたらす場合もある。 セイヨウオトギリの除草剤には 2,4-D、ピクロラム、グリホサートが有効である。 生物的駆除の目的で、オトギリソウ類を食べることで知られる3種の甲虫（ハムシ科・ヨモギハムシ属の2種：Chrysolina quadrigeminaとChrysolina hyperici、およびタマムシ科の1種：Agrilus hyperici）が北米西部で使われている。
セント・ジョーンズ・ワートの医療的利用の最初の記録は古代ギリシアにまでさかのぼり、以来利用されてきている。 またネイティブアメリカンも人工妊娠中絶薬 抗炎症剤、収斂剤 消毒剤として使用してきた。
現代医学において標準的なセント・ジョーンズ・ワートの抽出物はうつ病や不安障害の一般的な処置として用いられている。ホメオパシーにおいては多くの医学的な問題に対する処置として用いられるが、その効果の程は正確には記載されていない。歴史的にはセント・ジョーンズ・ワートの花や茎は赤や黄色の色素を作るために用いられてきた。
今日セント・ジョーンズ・ワートはうつ病への処置法（あるいはその可能性）として最も知られている。ドイツをはじめいくつかの国では軽度のうつに対して従来の抗うつ薬より広く処方されている[1]。標準的な抽出物はタブレット、カプセル、ティーバッグとして一般の薬局等で購入することが可能である。
欧州では、伝統的医薬品として流通しているが[2]日本においては、薬事法上、薬効を標榜しない限りは「食品」扱いであり、ハーブとして市販されている。しかし、多くの薬物と相互作用をするので、厚生労働省からも注意が必要であると喚起されている[2]。
セント・ジョーンズ・ワートについての臨床研究は、うつ病に対する効果を調査したものが多い。その結論は現在のところ成否さまざまである。軽症から中等症のうつに対して有効でかつ従来の抗うつ薬よりも副作用が少ないとするイギリスの診療ガイドラインにおける合意がある一方で、偽薬以上の効果は見られないとするアメリカで行われた研究もある。
英国国立医療技術評価機構（NICE）の2009年のうつ病に対する診療ガイドラインは、軽症から中等症のうつ病に対し危険性が利益を上回るため抗うつ薬は使用してはならないが、セント・ジョーンズ・ワートには利益がある可能性があるという証拠が存在するとしている[3]。
コクランレビューによる2008年の報告[4]は以下のように結論している。
なお以下の点が解釈を複雑にしていると記されている[4]。
1996年の初期のメタアナリシスでは、セント・ジョーンズ・ワートの抽出物は軽症から中等症のうつ病に対して偽薬より有意に有効であると報告された[5]。この研究は、23個のより小規模な先行研究をメタアナリシスしたものである。
このメタアナリシスは、後に27の研究を含めるように改訂され、コクランレビューへ掲載された。この改訂されたレビューはセント・ジョーンズ・ワートの抽出物は偽薬に有意に勝り（率比2.47: 95%信頼区間1.69から3.61）、標準的な抗うつ薬と同等の有効性であるとした（単独使用 1.01:0.87 から 1.16、複合使用1.52:0.78から2.94）[6] 。
包含する研究をより厳密な基準により選んだ1999年の別のメタアナリシスでは、セント・ジョーンズ・ワートは偽薬より効果があり（奏功率73.2 対 37.9%、 相対危険率 1.48: 95% 信頼区間 1.03–1.92）、三環系抗うつ剤と同等の効果がある一方で、悪影響が少ないことを見いだした（64 対 66.4%, 相対危険率 1.11 95% 信頼区間 0.92–1.29）[7]。1998年と1999年の2つの（大規模な）多施設平行研究でも、偽薬以上の有効性、標準的抗うつ剤と同等の効果、より少ない副作用などを示している[8][9][10]。
米国国立衛生研究所 (NIH) に属する米国国立補完代替医療センター (NCCAM) やその他の機関はうつ病に対しては、セント・ジョーンズ・ワートは偽薬と比較して極めて小さい効果しか示さないか、あるいはまったく効果を示さないとしている[11][12]。これらの結論は、NCCAMによって行われた大規模な臨床試験の結果に基づいている[13]。この研究は、DSM-IVに基いて大うつ病性障害と診断された340人の患者を対象に、ハミルトンうつ病評価尺度 (HAM-D) と 臨床全般印象尺度 (CGI) を症状評価尺度として用いた、多施設無作為二重盲検偽薬対照試験である。対照として、セルトラリン（SSRI）と偽薬を用いている。その結果、セント・ジョーンズ・ワートは中程度のうつ病に対して、偽薬に比べて有効性があることは示されなかった。しかし、抗うつ薬のセルトラリンも偽薬に比べて有効性があることは示されなかった。より軽度のうつ病における効果の調査がNIHにより計画されていると記されている。
代替医療についての他の多くの研究と同様に、これらの多くは方法論や研究デザインが不十分であり、有効性について結論づけることができない状態である。有効性を報告している研究者の一人も、今後より精密な調査が必要であることを2003年の論文中で述べてられている[6]。
DSM-IV基準を満たした注意欠陥多動性障害ADHDの小児および青年に対して、セント・ジョーンズ・ワート300mgによる改善効果を検討した無作為比較試験では臨床的に有効な改善効果は認められなかった[14]。
ハーブと花は異なるポリフェノールを含んでいる: フラボノイド類（ルチン、ヒペロシド、イソケルセチン、ケルシトリン、ケルセチン、I3,II8-ビアピゲニン、アメントフラボン、アスチルビン、ミクエリアニン）、フェノール酸（クロロゲン酸、3-O-クマロイルキナ酸）、ナフトジアントロン類（ヒペリシン、プソイドヒペリシン、プロトヒペリシン、プロトプソイドヒペリシン）、フロログルシノール類（ヒペルホリン、アドヒペルホリン）。
ヒペリシン、プソイドヒペリシンならびにヒペルホリンは活性成分であると考えられている[15][16][17]。その他精油成分（主にセスキテルペン）も含まれている。
セント・ジョーンズ・ワートが機能する機構は正確には不明であるが、従来の選択的セロトニン再取り込み阻害薬 (SSRI) 系の抗うつ薬と同様にセロトニンの再吸収を阻害することが関係すると信じられている[18]。
セント・ジョーンズ・ワートの主要な有効成分はハイパフォリンとヒペリシンだと考えられているが、フラボノイドやタンニンのような他の生理活性物質が関与している可能性もある[19][20][21]。
ハイパフォリンは抗うつ作用の主要な有効成分だと信じられており、セロトニン、ドーパミン、ノルアドレナリン、γ-アミノ酪酸 (GABA)、グルタミン酸の取込みを阻害することが示されている[22]。用量反応関係の不一致からハイパフォリン以外の成分の関与も示唆されている[23]。また、ハイパフォリンを含まないセント・ジョンズ・ワート抽出物 (Ze 117 - Remotiv) が顕著な抗うつ作用を示すという報告も成されている[24][25]。
セント・ジョーンズ・ワートの投与量は処方間で大きく隔たりがあり、それは植物原料と調整過程の違いによるものである。臨床試験で一般的に用いられる投与量は一日当たり350から1800mgである（これはヒペレリンで0.4から2.7mgに相当する）[6]。
英国ハーブ医学連合科学委員会により推薦されている様々な形態のセント・ジョーンズ・ワートの用量は以下の通りである [26]。
標準化された抽出物を入手できない市場では、物によってその強度が大きく異なる。薬局で手に入る某ブランドのものは、他のものより強い場合がある。また同じブランドでも、バッチが異なると用量が異なる場合がある。 標準化されたものが手に入る場所でも、ヘパフォリンが主要な活性成分だと考えられているため、ヒペリシンを基準に用いるのには議論がある。
他の抗うつ薬と同様に、セント・ジョーンズ・ワートの効果を適切に評価するためには、最低4週間は取り続けなければならない。
セント・ジョーンズ・ワートは一般に良好な耐容性を示し、プラセボと同程度の副作用しか示さない[27]。報告されている最も一般的な副作用は胃腸症状、目まい、意識混濁、けん怠、鎮静[28]。また 通常では起こさない状況でも日焼けを起こす 光過敏性を起こすことが知られているが、それが起きることは非常に稀である[27]。抗癌剤のFOLFIRI療法…カンプト(イリノテカン)投与時は、その作用を弱めるため、避けるようにと言われている。統合失調症を患っている人では精神病症状を悪化と関連があると思われる。[29]
セント・ジョーンズ・ワートは、シトクロームP450酵素 CYP3A4を誘導することで、ジゴキシン（強心薬）、シクロスポリン（免疫抑制薬）、テオフィリン（気管支拡張薬）、インジナビル（抗HIV薬）、ワルファリン（血液凝固防止薬）など、いくつもの薬物相互作用をすることが知られている。ハイパフォリンが主要な原因物質で、それが有効成分でもある。
セント・ジョーンズ・ワートは、ある種の薬物の量を体の中で減少させる作用があり、そのためその薬物の効果を減じさせる。他の抗うつ薬（SSRIや三環系抗うつ薬）、避妊薬、高脂血治療薬等[30]抗てんかん薬[31]。
セイヨウオトギリ（西洋弟切、学名：Hypericum perforatum、英語名：St. John's wort、Klamath weed、Goat weed）は、オトギリソウ科オトギリソウ属の多年草である。英語におけるセント・ジョーンズ・ワート (St. John's wort) は、本種の一般名だが、様々な修飾語とともに、オトギリソウ属の他種を指すこともあり、英語ではそれらと区別するために、本種を Common St. John's wort と呼ぶ場合もある。
서양고추나물(Hypericum perforatum), 세인트존스워트(perforate St John's-wort)[1], 망종화는 물레나물과에 속하는 속씨식물이며 물레나물속의 모식종이다.
Hypericum maculatum과 채고추나물의 잡종으로 추정되는 이 종은 유라시아의 온난 지대에서 볼 수 있으며 북아메리카와 남아메리카, 남아프리카와 오스트레일리아 다수 지역에 침입 잡초종으로 도입되었다. 이 종이 가축에 유해하고 처방의약품에 간섭을 줄 수 있지만 수세기에 걸쳐 전통약제로 사용되고 있고 21세기에 상업적으로 경작되고 있다.
서양고추나물(Hypericum perforatum), 세인트존스워트(perforate St John's-wort), 망종화는 물레나물과에 속하는 속씨식물이며 물레나물속의 모식종이다.
Hypericum maculatum과 채고추나물의 잡종으로 추정되는 이 종은 유라시아의 온난 지대에서 볼 수 있으며 북아메리카와 남아메리카, 남아프리카와 오스트레일리아 다수 지역에 침입 잡초종으로 도입되었다. 이 종이 가축에 유해하고 처방의약품에 간섭을 줄 수 있지만 수세기에 걸쳐 전통약제로 사용되고 있고 21세기에 상업적으로 경작되고 있다.
