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Preparative isolation and purification of theaflavins and catechins by high-speed countercurrent chromatography

时间:2017/05/12  作者:   点击:

 

 

 

High-speed countercurrent chromatography (HSCCC) has been applied for the separation of theaflavins and catechins. The HSCCC runwas carried out with a two-phase solvent systemcomposed of hexane–ethyl acetate–methanol–water–acetic acid (1:5:1:5:0.25, v/v) by eluting the lower aqueous phase at 2 ml/min at 700 rpm. The results indicated that pure theaflavin, theaflavins-3-gallate, theaflavins-3'-gallate and theaflavin-3,3' digallate could be obtained from crude theaflavins sample and black tea. The structures of the isolated compounds were positively confirmed by 1H NMR and 13C NMR, MS analysis, HPLC data and TLC data. Meanwhile, catechins including epigallocatechin gallate, gallocatechin gallate, epicatechin gallate and epigallocatechin were isolated from the aqueous extract of green tea by using the same solvent system. This study developed a modifiedmethod combined with enrichment theaflavins method by using HSCCC for separation of four individual theaflavins, especially for better separation of theaflavinsmonogallates.

Keywords: High-speed countercurrent chromatography Theaflavins Black tea Catechins Green tea

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