Liquid-liquid/solid three-phase high-speed counter-current chromatography, a new technique for separation of polyphenols from Geranium wilfordii Maxim

High-speed counter-current chromatography using a new liquidliquid/solid three-phase system was used for the separation of the polyphenols corilagin and geraniin from a crude extract of Geranium wilfordii Maxim in one step. The optimized three-phase system was composed of n-hexane/ethyl acetate/methanol/acetic acid/water and to which was added 10-mu m average diameter microspheres of cross-linked 12% agarose at the ratio of 0.2:10:2:1:5 and 0.1 g/mL, respectively. The purities of geraniin and corilagin were 82 and 90%, which were determined by HPLC at 280 nm. A 14.5 and 7 mg of geraniin and corilagin were purified from 160 mg crude extract with the yields of 70 and 78%, respectively.