Adulteration of Ginkgo biloba products and a simple method to improve its detection

Hans Wohlmuth , Kate Savage, Ashley Dowell, Peter Mouatt

Abstract

Extracts of ginkgo (Ginkgo biloba) leaf are widely available worldwide in herbal medicinal products, dietary supplements, botanicals and complementary medicines, and several pharmacopoeias contain monographs for ginkgo leaf, leaf extract and finished products. Being a high-value botanical commodity, ginkgo extracts may be the subject of economically motivated adulteration. We analysed eight ginkgo leaf retail products purchased in Australia and Denmark and found compelling evidence of adulteration with flavonol aglycones in three of these. The same three products also contained genistein, an isoflavone that does not occur in ginkgo leaf.

isorhamnetin (>98%) from Chengdu Biopurify Phytochemicals (Chengdu,Sichuan, China).