Isolation and preparation of five flavonol glycosides from Epimedium sagittatum by reversed phase liquid chromatography

Five flavonol glycosides in the extract of Epimedium sagittatum were isolated and prepared by semi-preparative reversed phase liquid chromatography (RPLC) and the chromatographic conditions were optimized. When 35 mL of extract were injected into the reversed phase liquid chromatogrpahy (RPLC) column, the purities of compound I (hexandraside F), II (epimedin A), III (epimedin B) and V (icariin) were all found to be more than 95% only by one run with RPLC. After ten RPLC runs, 93 mg of I, 71 mg of 11, 296 mg of M and 487 mg of V were obtained, respectively. However, the purity of compound IV (epimedin C) can be obtained to be more than 95% by re-separation by RPLC and 64 mg of compound IV was obtained finally by ten time runs. Their structures were identified and confirmed to be the foregoing five compounds of flavonol glycosides. In addition, hexandraside F was firstly isolated from the genus Epimedium.