Preparative isolation and purification of three flavonoids from the Chinese medicinal plant Epimedium koreamum Nakal by high-speed counter-current chromatography

A preparative high-speed counter-current chromatography (HSCCC) method for isolation and purification of flavonoids from the Chinese medicinal plant Epimedium koreamum Nakai was successfully established by using chloroform-methanol-water (4:3.5:2. v/v) as the two-phase solvent system. The method yielded 11.4 mg of epimedokoreanoside I. 46.5 mg of icariin and 17.7 mg of icariside II from 200 mg of the crude sample in one-step separation with the purity of 98.2%, 99.7% and 98.5%, respectively, as determined by high-performance liquid chromatography (HPLC). The structures of the flavonoids were identified by H-1 NMR and C-13 NMR. (C) 2004 Elsevier B.V. All rights reserved.