[Preparative separation of two xanthones from Halenia elliptica by high-speed counter-current chromatography]

A high performance method for isolation and purification of two xanthones from a crude extract of Halenia elliptica was successfully established by utilizing high-speed countercurrent chromatography (HSCCC). The separation was performed with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (5:5:7:5, v/v/v/v) with the lower phase as the mobile phase at a flow rate of 1.5 mL/min. The apparatus was rotated at 800 r/min. The effluent was detected at 254 nm. Under the optimized conditions, 18 mg of 1-hydroxy-2,3, 5-trimethoxyxanthone and 14 mg of 1-hydroxy-2,3,4,5-tetramethoxyxanthone were obtained from 100 mg of the crude extract of Halenia elliptica in one-step separation within 360 min. The results of high performance liquid chromatographic (HPLC) analysis showed that the purity of each of the target compounds was over 98%. The chemical structures of the two compounds were confirmed by 1H nuclear magnetic resonance (1H NMR) and 13C NMR. The established method is simple, highly efficient and suitable for large scale separation of xanthones from Halenia elliptica.