Isolation of a Tetrameric A-type Proanthocyanidin Containing Fraction from Fresh Tea (Camellia Sinensis) Leaves Using High-Speed Counter-Current Chromatography

A proanthocyanidin (PA) fraction containing tetrameric A- and B-type PAs was obtained after Sephadex LH-20 chromatography and high-speed counter-current chromatography (HSCCC) of a PA extract from fresh tea (Camellia sinensis) leaves. The biphasic solvent system hexane-ethyl acetate-methanol-water system (1:5:1:5), with the aqueous phase as the mobile phase, was selected on the basis of partition coefficient (K(D)1.02), settling time (18s), and stationary phase retention (60%). Electrospray ionization mass spectrometry (ESI-MS) indicated the presence of A-type linkages in the tetrameric PAs in one of the HSCCC fractions.