[Separation of echinacoside by reversed-phase preparative high performance liquid chromatography]

Echinacoside, one kind of phenylethanoid glycosides (PhGs), was isolated from the stems of Cistanche tubulosa (Schenk) R. Wight with a series of steps, including solvent extraction, D101 polymer adsorption column separation, Sephadex LH-20 separation, C18 column reversed-phase preparative high performance liquid chromatographic (RP-prep-HPLC) preparation and polyamide thin-layer chromatographic detection. The purity of the product was over 98%. The chemical structure of echinacoside was identified by 1H NMR and 13C NMR. To find out the optimum condition of mobile phase of RP-prep-HPLC, several systems were used in this work. Finally acetonitrile-1% HCOOH water (18:82, V/V) system was found to be the best. On the other hand D101 polymer adsorption column and Sephadex LH-20 were also effective for PhGs separation.