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|Date: February 28, 2005||HC# 020151-275|
Re: 85-year-old Black Cohosh Specimen Tested for Active Ingredients
Jiang B, Yang H, Nuntanakorn P, et al. The value of plant collections in ethnopharmacology: a case study of an 85-year-old black cohosh (Actaea racemosa L.) sample. J of Ethnopharmacol. 2005;96:521-528.
Valuable but underutilized resources for scientific investigation in the field of ethnopharmacology are the plant samples that were collected in the late 1800s and early 1900s by world explorers. These ethnopharmacological collections were used to teach students about the pharmacopeia of the time and ended up as displays in museums, botanical gardens, and universities. The authors believe that these collections are still a valuable teaching resource and "represent a snapshot in time of the chemistry and utilization by past cultures that can never be recreated, and thus should be recognized and supported for their value to science."
A sample of black cohosh (Actaea racemosa syn. Cimicifuga racemosa), collected in 1919 by the physician and botanist Henry Hurd Rusby (1855–1940), was recently identified in the collections of The New York Botanical Garden. Black cohosh has a long history of medicinal use in North America. Native Americans and early colonists used its roots to treat conditions such as malaise, malaria, rheumatism, menstrual irregularities, kidney disorders, and sore throat. Currently, black cohosh is touted primarily for its role in alleviating the symptoms of menopause and is available commercially under a variety of brand names. The authors compared the constituents and stability of this 85-year-old sample of black cohosh with contemporary samples of the same species.
The 85-year-old sample was thought to have been collected from Montclair Heights, New Jersey. It had been exhibited and stored under a variety of environmental conditions over this period of time, including conditions that are not considered favorable to preservation. The roots and rhizomes of the modern sample of black cohosh were collected in the northeastern United States. The triterpene glycosidic and phenolic constituents of both samples were quantitatively and qualitatively analyzed by high-performance liquid chromatography–photodiode array detection (HPLC-PDA) and by liquid chromatography–mass spectrometry (LC-MS). In addition, methanol extracts of the two plant samples were tested for their antioxidant activities. All experiments were performed in duplicate in order to act as mutual controls.
Both HPLC-PDA and LC-MS analysis indicated that the compositions of triterpene glycosides and phenolic compounds in the 85-year-old sample of black cohosh were similar to those of the modern sample, which confirmed the stability of the compounds in the older sample. Quantitative analysis indicated that both plant samples had similar amounts of the four major triterpene glycosides measured (23-epi-26-deoxyactein, actein, cimiracemoside C, and cimigenoside): 4.43%–4.73% by HPLC-PDA and 4.06%–5.18% by LC-MS. However, the six major phenolic compounds measured (caffeic acid, ferulic acid, isoferulic acid, fukinolic acid, cimicifugic acid A, and cimicifugic acid B) were slightly lower in the 85-year-old sample. HPLC-PDA showed a total amount of 4.25% phenolic compounds in the 85-year-old sample and 5.68% in the modern sample. The difference in content of phenolic compounds between the two plant samples was thought to be due to genetic or metabolic properties of the plants, plant growing conditions, or time of harvesting and not due to decomposition of the constituent compounds. Similar antioxidant activities were found in the methanol extracts of the two plant samples.
The authors conclude that the phytochemical profiles of the 85-year-old black cohosh sample and the modern sample were "remarkably similar." This finding indicates that black cohosh products have the potential to be stored for longer periods of time than once thought without "major changes in its triterpenoid and phenolic profiles." The study of other such historic plant materials will be valuable for determining information on the stability of constituent compounds and evolutionary and genetic changes.
Mark Blumenthal, founder and executive director of the American Botanical Council, said, "This research supports what many scientists have known for a long time -- that some herbs have biologically active compounds that are stable for many years. We have known this for the ginsenosides in ginseng root and now we have confirmation that some of the key compounds in black cohosh do not break down over time. This may have some relevance to the good manufacturing practices (GMPs) that are expected soon from the Food and Drug Administration regarding requirements of expiration dates on herbal dietary supplement labels."
—Brenda Milot, ELS