Submitted to: Experimental Biology
Publication Type: Abstract only
Publication Acceptance Date: 11/3/2006
Publication Date: 4/1/2007
Citation: Ozcan, M., Chen, P. 2007. Determination of Ginkgolides and Flavonols in Ginkgo Biloba Products and NIST Ginkgo Reference Standard by LC/UV/MS. Experimental Biology, April 25, 2007, Washington, D.C. Interpretive Summary:
Technical Abstract: The leaf extract of Ginkgo biloba has purported value for improving mental capacities in Alzheimer’s patients. The flavonols and the terpene lactones are considered to be the two main active components that influence human health. Almost all the clinical studies regarding Ginkgo biloba used either EGb 761®, a proprietary extract of Ginkgo biloba leaves, or an extract prepared according to the same standard. Consequently, most of the commercial Ginkgo biloba products labeled their content accordingly. This paper studied the compositions of both flavonols and terpene lactones of seven commercially available Ginkgo biloba products and three standard reference materials (SRM 3246 Ginkgo biloba leaves, SRM 3247 Ginkgo biloba extract, and SRM 3248 Ginkgo biloba tablet) from the National Institute of Standards and Technology (NIST). The study employed a chromatographic method with UV and mass spectroscopic detection for determining the composition of flavonols and the terpene lactones in Ginkgo products using a gradient reversed-phase HPLC method. Methanol-water (1:1) extracts of terpene lactones and flavonols of the investigated Ginkgo biloba products and NIST standard reference materials were analyzed qualitatively and quantitatively. While the relative compositions of the flavonol glycosides were similar for the NIST SRMs, those for the commercial Ginkgo biloba products varied significantly. The relative concentrations of terpene lactones also showed significant differences between products, but not as dramatic as the flavonols.