溶剂量子化学特性对鱼油多不饱和脂酰甘油酯非水相酶促合成作用的影响

鱼油多不饱和脂酰甘油酯非水相酶促合成率与底物摩尔比例、反应温度、溶剂分子性质及溶剂系统中的最初水分含量有密切关系。溶剂分子的量子化学特性对非水相酶促酯化反应具有极为重要的影响。酯化率依溶剂分子最高占有轨道能量的增高及前沿轨道能差的减少而增加。溶剂分子电荷密度、静电势及前沿轨道系数对酯化率无显著影响。说明溶剂分子内不存在作用中心，溶剂分子主要是为非水相酶促酯化反应提供易于形成酶一底物电荷转移复合物的诱导场环境。

Effects of the quantum chemistry character of organic solvents on lipase-catalyzed esterification of glycerol and polyunsaturated fatty acids

Enzymatic synthesis of glycerides ftom glycerol and n-3 polyunsaturated fatty acids inorganic solvent was studied. optimal conditions for glyceride synthesis by lipase were 33.8C, 4%~5%water content in the reaction mixture, and 25 mmol glycerol for 0. 5gpolynsaturated fatty acids. The molecular character of organic solvents had much impor-tant eflects on glyceride syfithesis. With the increase of EHOMO and the decrease of ELUMOMEHOMO of orgnic solvent, the degree of glycerids synthesis increased significantly. Dipolarmovement, charge density, frontier molecular orbital coeffcients, and other quantumchenlistry parameters of organic solvents had not significant effects on esterification bylipase. It was suggested that organic solvents maight provide an induced field for theformation of enzyme-substrate complex of charge transfer.