Black Cohosh Root Shows Strong Long-term Chemical Stability

Black Cohosh Root Shows Strong Long-term Chemical Stability

AUSTIN, TexasAn 85-year-oldspecimen of black cohosh root still contains much of its active compounds,according to a study conducted at the New York Botanical Garden (NYBG) at LehmanCollege, City University of New York, and Columbia University, and published inthe April issue of the Journal of Ethnopharmacology (www.sciencedirect.com/science/journal/03788741).

Researchers assayed a specimen of black cohosh root (Actaearacemosa, syn. Cimicifugaracemosa)a botanical believed to reduce hot flashesand other symptoms in menopausal womenfor levels of naturally occurringcompounds believed to be responsible for the roots medicinal activity. Thespecimen was part of the public exhibits of NYBG until the 1930s, when thepowdered herb was placed in storage.

Comparison of the 85-year-old sample with those of a recentlycollected sample showed similar profiles, confirming the chemical stability ofthe older sample, in spite of its age and exposure to a variety of conditionsover the years.

Researcher Michael Balick, Ph.D., said the results show thepresent value of historic 19th and 20th century plant and other biologicalcollections as reference standards and scientific vouchers. What our team hasshown in this study is that, at least in the case of black cohosh, some keyplant compounds that are commonly thought to have a very short shelf life ofonly a few years actually lasted nearly a century, despite the fact that theywere exposed to light, humidity and less-thanoptimal storage conditions fordecades, Balick said. While many herb companies normally put a two- tothree-year expiration date on their herbal supplements, this research suggeststhat some supplement ingredients might be active for many, many years beyondtheir expected shelf life. It is time to use this same technique to look atother herbal samples that were collected in the late 1800s and early 1900s thatstill exist in NYBGs collections, and elsewhere, to investigate the stabilityof plant chemicals present in herbal medicines.

According to Mark Blumenthal, founder and executive directorof the American Botanical Council, the results of the study may haveimplications for regulatory practices for herbal dietary supplements. The results of this study are relevant to the final rulesfor good manufacturing practices (GMPs) that are expected soon from the Food andDrug Administration (FDA). These new regulations deal with expiration dates forherbal dietary supplement labels and how manufacturers determine the shelf lifeof these products.