[Determination of 7 flavonol glycosides in Ginkgo biloba reference extract].

Six flavonol glycosides were isolated and calibrated from Ginkgo biloba extract, and then used to calibrate the content in 2 baiches of G. biloba reference extract, so was rutin. RSD values of rutin, kaempferol-3-O-rutinoside, kaempferol-3-O-rhamnoside-2-glu- coside, quercetin-3-O-rhamnop-yranosyl-2-O-(6-O-p-coumaroyl)-glucoside, kaempferol-3-O-rhamnopyranosyl-2-O-(6-O-p-coum-aroyl) - glucoside were around 1.1%-4.6%, nevertheless, RSD values of quercetin-3-O-glucoside and isorhamnetin-3-O-rutinoside were more than 5%. According to the results, the reference extract of G. biloba can be used as the substitute to determine rutin, kaempferol-3-O- rutinoside, kaempferol-3-O-rhamnoside-2-glucoside, quercetin-3-O-rhamnopyranosyl-2-O-(6-O-p-coumaroyl)-glucoside and kaempferol-3-0-rhamnopyranosyl-2-O-(6-O-p-coumaroyl)-glucoside instead of corresponding reference substances. So reference extract in place of single component reference in assay is feasible.