Золототысячник канадский: биология, распространение и угрозы исчезновения

Species of flowering plant
the magazine from West Virginia

Goldenseal (Hydrastis canadensis), also called orangeroot or yellow puccoon, and sexually, with clonal division more frequent than asexual reproduction. It takes between 4 and 5 years for a plant to reach sexual maturity, i. e. the point at which it produces flowers. Plants in the first stage, when the seed erupts and cotyledons emerge, can remain in this state one or more years. The second vegetative stage occurs during years two and three (and sometimes longer) and is characterized by the development of a single leaf and absence of a well developed stem. Finally, the third stage is reproductive, at which point flowering and fruiting occurs. This last stage takes between 4 and 5 years to develop. A second species from Japan, previously listed as Hydrastis palmatum, is now usually classified in another genus, as Glaucidium palmatum.

Hydrastis canadensis is a herbaceous perennial growing from a horizontal, yellowish rhizome that is thick with knobby knots. The finely hairy, upright, unbranched, stems grow to tall. Fertile plants have a single stem with two palmately lobed leaves. Flowering plants produce a single terminal flower with no petals and three sepals and 12 or more conspicuous white pistils; flowering occurs for a short time in spring. A related compound, 8 oxotetrahydrothalifendine, was identified in one study. The United States Pharmacopoeia requires goldenseal sold as a supplement to have hydrastine concentrations of at least 2% and berberine concentrations of at least 2.5%. The requirements in Europe are that hydrastine concentrations be at least 2.5% and that berberine concentrations at least 3%. Goldenseal is harvested for its rhizomes because the concentrations of hydrastine and berberine in the shoots do not meet these requirements.

Found in southeastern Canada and the eastern United States, the plant grows in mesic forests under deciduous trees. meaning a CITES permit to export is required. The U. S. Fish and Wildlife Service recommends that diggers and harvesters track sales and harvests and prove legality of all harvests. Canada, as well as 17 of the 27 U. S. states where goldenseal grows natively, have declared it as threatened, vulnerable or uncommon. More than 60 million goldenseal plants are picked each year without being replaced. Although goldenseal's geographical range is wide, it is found in small quantities in these habitats. The process of mountain top removal mining has recently put the wild goldenseal population at major risk from loss of habitat. Many herbalists urge caution in choosing products containing goldenseal, as they may have been harvested in an unsustainable manner rather than having been organically cultivated. There are several berberine containing plants that can serve as useful alternatives, including Chinese coptis, yellowroot or Oregon grape root.

According to the American Cancer Society, "Goldenseal can have toxic side effects, and high doses can cause death." Side effects of goldenseal may include "digestive complaints, nervousness, depression, constipation, rapid heartbeat, diarrhea, stomach cramps and pain, mouth ulcers, nausea, seizures, vomiting, and central nervous system depression. High doses may cause breathing problems, paralysis, and even death. Long term use may lead to vitamin B deficiency, hallucinations, and delirium." and may affect blood pressure unpredictably because it contains several compounds that have opposite effects on blood pressure. A 2011 study found rats fed goldenseal constantly for two years had a greater tendency to develop tumors. Goldenseal has been found to have inhibited cytochrome P450 CYP2D6, CYP3A4 and CYP3A5 activity by approximately 40%, a statistically and clinically significant reduction. CYP2D6 is a known metabolizer of many commonly used pharmaceuticals, such as antidepressants (including all SSRIs except for fluvoxamine), neuroleptics, codeine, and Metformin. Combining goldenseal with such medications should be done with caution and under the supervision of a doctor as it can lead to serious, perhaps fatal, toxicity. Those with a genetic deficiency in these enzymes are at particular risk.

As of 1998, only 2.4% of goldenseal plant material originated from a cultivated source rather than wild harvest, although that number was projected to rise by 15–30% over the next several years. Seed propagation is also feasible and has advantages such as lower cost and greater genetic variability, but is considered difficult and unpredictable. Goldenseal may be commercially cultivated through agroforestry in natural settings mirroring the plant's ecological environment, or on farms with artificial shade canopies. Controlled environments can greatly reduce the amount of time required to grow goldenseal to its desired harvestable state. While forest cultivated plants double in mass every three to five years, plants can double in mass every 15 weeks in growth chambers and triple in growth when in a course soil medium. Subculturing can take place every 30 days to mass propagate the plant. Another option is cultivating goldenseal in new regions. An experiment conducted by Douglas et al. grew goldenseal over a six year period in a warm, temperate environment in New Zealand. The yields were 74% higher in the sixth year of growth compared to the fourth year of growth, which is when goldenseal is normally harvested. on the effects of soil turnover, fertilization and transplanting of goldenseal show that disturbances actually benefit the growth of goldenseal. The results from the first growing season of the experiment showed that soil turnover and fertilization combined show the greatest increase in plant biomass, he called attention to its properties as a bitter tonic, and as a local wash for ophthalmia. It became a favorite of the Eclectics from the time of Constantine Raffinesque in the 1830s. Tribes also used goldenseal for digestive issues, as an eyewash, as a diuretic and as a bitter. In the early 20th century, it was used as a yellow dye, astringent, and insect repellent.