Qz. Du et al., Separation of theaflavins of black tea. High-speed countercurrent chromatography vs. sephadex LH-20 gel column chromatography, J LIQ CHR R, 24(15), 2001, pp. 2363-2369
Performance of two chromatographic techniques, high-speed countercurrent ch
romatography (HSCCC) and conventional Sephadex LH-20 gel column chromatogra
phy (GLC), was compared in the separation of theaflavins from the extract o
f black tea leaves. The HSCCC run was carried out with a two-phase solvent
system composed of hexane/ethyl acetate/methanol/water (1:3:1:6, v/v) by el
uting the lower aqueous phase at 2 mL/min at 800 rpm where 200 mg of the sa
mple was resolved into three peaks corresponding to theaflavin, theaflavin-
3,3'-gallate, and a mixture of theaflavin-3-gallate and theaflavin-3'-galla
te in 4.1 hrs. Although, Sephadex column chromatography yielded a similar s
eparation for 100 mg of the same sample, it required a much longer elution
time of 21 hrs.