Separation of theaflavins of black tea. high-speed countercurrent chromatography vs. sephadex LH-20 gel column chromatography

摘要

Performance of two chromatographic techniques, high-speed countercurrent chromatography (HSCCC) and conventional Sephadex LH-20 gel column chromatography (GLC), was compared in the separation of theaflavins from the extract of black tea leaves. The HSCCC run was carried out with a two-phase solvent system composed of hexane/ethyl acetate/methanol/water (1:3.1:1:6, v/v) by eluting of lower aqueous phase at 2 mL/min at 800 rpm where 200 mg of the sample was resolved into three peaks corresponding to theaflavin, theaflavin-3,3'-gallate, and a mixture of theaflavin-3-gallate and theaflavin-3'-gallate in 4.1 hrs. Although, Sephadex column chromatography yielded a similar separation for 100 mg of the same sample. It required a much longer elution time of 21 hrs.