Isolation and Purification of ginkgo flavonoids by High-speed Counter-current Chromatography

High-speed counter-current chromatography(HSCCC) was successfully used for isolation and purification of Ginkgo flavonoids from the Ginkgo biloba L. leaf extract (GBE) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at an optimized volume ratio of 4:6:5:5(v/v/v/v). The lower phase was used as the mobile phase in the head to tail elution mode. The preparative HSCCC separation was performed on 200 mg of GBE yielding pure Quercetin(22mg), Kaempferol(15mg) and Isorhamnetin(4mg) at purities of 96.6%, 92.3% and 93.6%, respectively, as determined by high performance liquid chromatography (HPLC). HSCCC is a powerful technique for isolation and separation of chemical composition from GBE.