Chromatographic profiles of Ginkgo biloba leaves and selected products

Ginkgo biloba leaves and their extracts are one of the most widely used herbal products in the world. Their flavonoids and terpene lactones are considered to be the main beneficial components. Previous studies have focused on specific components, or families of components, but a comprehensive study to identify all phenolic components is lacking. A method based on liquid chromatography separation and detection by diode array and electrospray ionization/mass spectrometry (LC‐DAD‐ESI/MS) was developed to obtain chromatographic profiles for the flavonoids and terpene lactones of Ginkgo biloba leaves. The method was used to identify 46 glycosylated flavonols and flavones, 3 free aglycones, catechin, 10 biflavones, 3,4‐dihydroxybenzoic acid, and 4 terpene lactones in aqueous methanol extracts of the leaf materials. The phenolics content of the Ginkgo biloba products were the same as the raw leaves, with the exception of the biflavones, which were only found in the raw leaves. This is the first report for more than 20 of the flavonoids found in Ginkgo biloba leaves. This research was funded by USDA and the Office of Dietary Supplements at the National Institutes of Health.