α-glycosidase inhibitors in dark tea were studied systematically by the method of a combination ofrnextraction with 60% ethanol.fractionation on D101 column,and further purification by HSCCC ordinally. Thernresult showed that fractions D-6.D-7 and D-8 obtained by D101 column chromatography indicated higherrninhibitory activity than 60% ethanol extract of dark tea in the concentration 25μg/mL, inhibition were 69.31%,rn77.53% and 75.23%, respectively. Fraction D -7 was selected to further separation by HSCCC with solventrnsystem ethyl acetate-n-buthanol-methanol-water-acetic acid (4:1:1:4:0.1 ,v/v). Compound 1 (vitexin) andrncompound 2 (isovitexin) were obtained by one step HSCCC separation with purities higher than 95%,rnrespectively.%采用白叶单枞黑茶的60％乙醇提取物,在α-葡萄糖苷酶抑制活性的导向下,经D101大孔吸附树脂柱层析获得活性流分,进一步采用高速逆流色谱法(HSCCC)进行分离纯化研究.结果显示,黑茶60％乙醇提取物具有较显著的α-葡萄糖苷酶抑制活性,经D101柱层析所得的流分D-6、D-7及D-8在25 μg/mL浓度下具有较黑茶60％乙醇提取物强的酶抑制活性,酶活性抑制率分别为69.31％、77.53％及75.23％.对活性流分D-7采用溶剂系统:乙酸乙酯-正丁醇-甲醇-水-乙酸(4∶1∶1∶4∶0.1,v/v)进行了HSCCC分离,得到化合物1、2,纯度均大于95％,经结构鉴定确定二者分别为牡荆苷、异牡荆苷.
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