Rhodiola rosea (commonly golden root, rose root, roseroot, Aaron's rod, Arctic root, king's crown, lignum rhodium, orpin rose) is a perennial flowering plant in the family Crassulaceae. It grows naturally in wild Arctic regions of Europe (including Britain), Asia, and North America (New Brunswick, Newfoundland and Labrador, Nova Scotia, Quebec; Alaska, Maine, New York, North Carolina, Pennsylvania, Vermont), and can be propagated as a groundcover. Supply comes mostly from wild harvesting on an industrial scale, and a combination of growing scarcity and a lack of regulation has led to environmental degradation, substitution or adulteration in the market, and illegal harvesting in protected areas.
Description
Rhodiola rosea is from tall, fleshy, and has several stems growing from a short, scaly rootstock. Flowers have 4 sepals and 4 petals, yellow to greenish yellow in color sometimes tipped with red, about long, and blooming in summer. Several shoots growing from the same thick root may reach in height. R. rosea is dioecious – having separate female and male plants.
thumb|Rhodiola rosea in flower during the spring in the UK
thumb|Rhodiola rosea sprouting new growth
thumb|right|Wild Rhodiola rosea plant
thumb|right|Dried R. rosea root
Taxonomy
Rhodiola rosea was first described by Pedanius Dioscorides in De Materia Medica. Rhodiola roots contain phenols, rosavin, rosin, rosarin, organic acids, terpenoids, phenolic acids and their derivatives, flavonoids, anthraquinones, alkaloids, tyrosol, and salidroside.
The chemical composition of the essential oil from R. rosea root growing in different countries varies. For example, rosavin, rosarin, and rosin at their highest concentration according to many tests can be found only in R. rosea of Russian origin; the main components of the essential oil from Rhodiola growing in Bulgaria are geraniol and myrtenol; in China the main components are geraniol and 1-octanol; and in India the main component is phenethyl alcohol. Cinnamyl alcohol was discovered only in the sample from Bulgaria.
Although rosavin, rosarin, rosin, and salidroside (and sometimes p-tyrosol, rhodioniside, rhodiolin, and rosiridin) are among suspected active ingredients of R. rosea, these compounds are mostly polyphenols. There are no peer-reviewed studies demonstrating that these chemicals have any physiological effect in humans that could prevent or reduce risk of disease. Although these phytochemicals are typically mentioned as specific to Rhodiola rosea extracts, rosea and other Rhodiola species contain many other constituent polyphenols, including proanthocyanidins, quercetin, gallic acid, chlorogenic acid and kaempferol.
Distribution
Rhodiola rosea grows in cold regions of the world, including much of the Arctic, the mountains of Central Asia, scattered in eastern North America and mountainous parts of Europe. An extract is sometimes added as a flavoring in vodkas.
Research and regulation
Rhodiola has been used as a dietary supplement. According to Memorial Sloan Kettering Cancer Center, Rhodiola rosea is used in Asia and Eastern Europe in the forms of capsules, liquid extracts and tablets as a traditional medicine. Through 2019, human studies evaluating R. rosea did not have sufficient quality to determine whether it has properties affecting fatigue or any other condition. The U.S. Food and Drug Administration (FDA) has issued warning letters to manufacturers of R. rosea dietary supplement products unapproved as new drugs, adulterated, misbranded and in federal violation for not having proof of safety or efficacy for the advertised conditions of alleviating Raynaud syndrome, altitude sickness, depression or cancer.
A 2012 report by the European Medicines Agency on literature concerning the dried extract of R. rosea stated that "The published clinical trials exhibit considerable deficiencies in their quality. Therefore 'well-established use' cannot be accepted".
Protection and management
Rhodiola rosea has not been assessed on the IUCN red list, but is listed on the CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) Appendix II which "includes species not necessarily threatened with extinction, but in which trade must be controlled in order to avoid utilization incompatible with their survival.".
See also
- Rhodiola
- Rhodiola integrifolia