One-step separation of four flavonoids from Herba Salviae Plbeiae by HSCCC.

High-speed countercurrent chromatography (HSCCC) was successfully applied to the isolation and purification of four flavonoids from Herba Salviae Plbeiae using stepwise and dual-mode elution with a pair of two-phase solvent systems. The systems composed of n-hexane-chloroform-methanol-water (0.5 : 4 : 3 : 2, v/v/v/v) and chloroform-methanol-water (4 : 3 : 2, v/v/v). Analytical HSCCC was used for the preliminary selection of a suitable system, and a linear scale-step procedure was performed at a preparative grade. Hispidulin (91 mg), nepetin (148 mg), homoplantaginin (405 mg) and nepetin-7-glucoside (192 mg) could be obtained from 1,500-mg crude sample in a one-step separation, with purities >95% as determined by high-performance liquid chromatography. Their chemical structures were identified by (1)H nuclear magnetic resonance (NMR) and (13)C NMR.