用没食子酸酯萃取分离酯型儿茶素单体

Extraction of ester catechins with gallate ester

以疏水性没食子酸酯为萃取剂研究天然酯型儿茶素单体在水-有机醇两相体系中的分配行为,考察没食子酸酯烷基链长度、没食子酸酯浓度、萃取温度和振荡时间等因素对分配系数和分离因子的影响。研究结果表明:没食子酸酯与表儿茶素没食子酸酯形成复合物的稳定性比与其他2种单体(表没食子儿茶素没食子酸酯和没食子儿茶素没食子酸酯)形成的复合物的稳定性强,且当没食子酸正十二酯浓度为0.15 mol/L,温度为20℃,振荡时间为30 min时,表没食子儿茶素没食子酸酯、表儿茶素没食子酸酯和没食子儿茶素没食子酸酯的分配系数KEGCG,KECG和KGCG分别为13.32,6.04和1.65;分离因子1α和2α分别为3.7和2.2。

The distribution behavior of ester catechins monomers in the aqueousorganic alcohol of two-phase system containing one of the gallate esters was studied. The influences of alkyl chain length of gallate esters, concentration of gallate esters, extraction temperature and shaking time on the partition coefficients and separation factors of ester catechins were investigated. The results show that the gallate esters form more stable complexes with epicatechin gallate than with epigallocathechin gallate and gallocatechin gallate, and the partition coefficients of epigallocathechin gallate KEGCG, epicatechin gallate KECG, gallocatechin gallate KGCG are 13.32, 6.04, 1.65, respectively, and the separation factors of a1 and a2 are 3.7, 2.2, respectively.