Preparative isolation of four new and two known flavonoids from the leaf of Patrinia villosa Juss. by counter-current chromatography and evaluation of their anticancer activities in vitro

A preparative counter-current chromatography (CCC) was used to isolate and separate chemical constituents from the leaf of Patrinia villosa, a famous traditional Chinese medicinal herb. Six flavonoids including two known and four novel compounds were successfully simultaneous purified by CCC with a two-phase solvent system composed of n-hexane–ethyl acetate–methanol–water (10: 13: 13: 10, v/v) by increasing the flow rate of the mobile phase from...