采用制备高效液相色谱对叔戊醇中固定化脂肪酶Novozym 435催化合成的柚皮苷棕榈酸酯进行分离纯化,利用红外光谱、质谱、核磁共振碳谱对产物进行分析,并对酶催化的区域选择性反应机理进行探讨.确定了适宜的色谱条件:C18色谱柱(21.5 mm×250.0mm,10μm),流动相为甲醇,流速为20 mL/min,进样质量浓度为30 mg/mL,进样体积为3mL,此条件下分离得到的产物纯度〉99%;产物为柚皮苷棕榈酸单酯,酰基化选择性地发生在柚皮苷的葡萄糖基的6″-羟基位上.
First,preparative high-pressure liquid chromatography was used to isolate and purify the naringin palmitate enzymatically synthesized by immobilized lipase Novozym 435 in the t-amyl alcohol system.Next,IR spectrum,mass spectrum and 13C NMR were used to identify the purified product,and the mechanism of regioselectivity of the reaction was discussed.Then,the feasible operation conditions were determined as follows: a C18 column(21.5mm×250.00mm,10μm) with methanol as the mobile phase at a flowrate of 20mL/min,an injection volume of 3mL with the concentration of 30mg/mL.In these conditions,the product with a purity of more than 99% was obtained.Finally,the purified product was identified as monoester of naringin and palmitic acid,and the regioselective acylation was found preferring the 6″-hydroxyl group of naringin glucose.