[Isolation and preparation of polyphenols from grape seed by high-speed counter-current chromatography combined with...

Eight polyphenols were separated from grape seed by high-speed counter-current chromatography (HSCCC). The separation was performed using a two-phase solvent system composed of 1-butanol-ethyl-water (1:14:15, v/v/v) and n-hexane-ethyl-water (1:10:10, v/v/v). The upper and lower phases were used as the stationary and mobile phases, respectively. A flow rate of 2.0 mL/min was employed for the separation. The apparatus was rotated at 900 r/min, and the detection wavelength was set at 280 nm. Under the selected conditions, procyanidins B₁, procyanidins B₂, gallic acid, epicatechin gallate, and catechin were obtained from the grape seed extracts with a purity of 98.5%, 97.2%, 98.3%, 98.9%, and 96.7%, respectively. Epicatechin, epicatechin gallate, and gallocatechin gallate were obtained by preparative high performance liquid chromatography with the purity of 99.2%, 99.3%, and 99.2%, respectively. The proposed method is simple and shows high separation efficiency, and will be of great importance for the comprehensive utilization of grape seed.