Significant differences in alkaloid content of Coptis chinensis (Huanglian), from its related American species

BACKGROUND: The growing popularity of Chinese herbal medicine in the United States has prompted large-scale import of raw herbs from Asia. Many of the Asian herbs have phylogenetically related North American species. We compared three phylogenetically related species, namely Coptis chinensis (Huanglian), Hydrastis canadensis and Coptis trifolia to show whether they can be substituted by one another in terms of alkaloid content. METHODS: We used microwave assisted extraction to obtain alkaloids berberine, coptisine, palmatine and hydrastine. High performance liquid chromatography (HPLC) was used to quantify each alkaloid. RESULTS: Hydrastis canadensis has the most berberine, whereas Coptis trifolia has the most coptisine. Hydrastine and palmatine were unique to Hydrastis canadensis and Coptis chinensis respectively. CONCLUSION: Neither Hydrastis canadensis nor Coptis trifolia contains all the alkaloids found in Coptis chinensis used in Chinese medicine. Substitutes of this Chinese species by its American relatives are not recommended.