采用柱色谱和高效制备液相色谱法从茶叶中分离制备2种甲基化EGCG(EGCG 3"Me和EGCG 4"Me)。用含水的乙酸乙酯提取茶叶,粗提液浓缩后经HP-20柱色谱分离,再经制备液相色谱分离,以水和乙腈为流动相进行梯度洗脱得到2种甲基化EGCG。经紫外光谱、核磁共振及质谱分析,进一步确定2种甲基化EGCG分别为EGCG3"Me和EGCG4"Me。所制备的2种甲基化EGCG的纯度在98%以上。
:A method was established to isolate EGCG3"Me and EGCG 4"Me by using column chromatography and preparative high performance liquid chromatography. Crude extracts was obtained from tea leaves by using ethyl acetate and water as solvent .Then the concentracted crude extract was separated on a HP-20 column. The Fr-1 fraction was obtained from the eluate of 80% ethanol and subjected to a preparative high performance liquid chromatography for isolation of target components by using water-acetonitrile as mobile phase. Two compounds were identified with ultraviolet absorbance(UV), nuclear magnetic resonance(NMR), mass spectrometry(MS). They were EGCG3"Me and EGCG4"Me.The purity of them was more than 98%.
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