无溶剂酶催化油脂甘油解中温度效应的研究

以荧光假单胞菌脂肪酶为催化剂 ,进行无溶剂油脂甘油解反应合成单脂肪酸甘油酯。实验结果表明 :反应 2 4h时在所有实验体系中 ,反应温度高于 46℃时 ,产物中单甘酯平衡质量分数均低于 30 % ,最佳反应温度与体系最低共熔点有关。当体系最低共熔点约在 35～ 45℃时 ,临界温度 (TC)现象较明显 ,最佳反应温度接近于此反应体系的最低共熔点。油脂熔点和体系最低共熔点低于 35℃时 ,最佳反应温度及临界温度高于最低共熔点 ;油脂熔点和体系最低共熔点高于 45℃时 ,最佳反应温度低于最低共熔点。提出了第一临界温度和第二临界温度的概念

Temperature Effects on Enzymatic Oil Glycerolysis in Solvent-Free System

Enzymatic synthesis of monoglycerides (MG) catalyzed by a lipase from Pseudomonas fluorescens with glycerolysis of several oils in a solventfree system was investigated especially for the effect of temperature on the contents of the MG in reaction mixtures after 24 h.The suitable reaction temperature should be lower than 46 ℃,and was related to the lowest comelting point(CoMp) of the reaction system.There was an evident critical temperature(T C) if the CoMp was between 35-45 ℃ and the optimum reaction temperature was near T C and close to the CoMp.The optimum reaction temperature would be higher than the CoMp if the CoMp was lower than 35 ℃, and lower than the CoMp if it was higher than 45 ℃.The concepts of first and second T C were given.