【摘要】 在无溶剂反应系统中，研究了固定化假丝酵母（Ｃａｎｄｉｄａｓｐ．）１６１９脂肪酶催化合成聚乙二醇４００（ＰＥＧ４００）月桂酸酯的酯化条件。在反应过程中不断脱水和使月桂酸的量高于化学计量值的方法，使酯化率明显提高。分批补加ＰＥＧ４００使产量进一步增加。在５０ｍｍｏｌ月桂酸，２５ｍｍｏｌＰＥＧ４００，２０ｍｇ固定化脂肪酶（２００ｕ），０２ｍｌ水组成的反应体系中，４０℃，锥形瓶敞口振荡反应４８ｈ，酯化率达９１％；在负压条件下反应，酯化率达９８９％；反应体系中月桂酸的量增加到６０ｍｍｏｌ时，ＰＥＧ４００完全被酯化。用己烷提取产物的收率为９５％，通过薄层色谱鉴定酯化产物为双酯更多还原

【Abstract】 Conditions for the esterification of polyethylene glycol 400 (PEG 400 ) with lauric acid by immobilized lipase from Candida sp. 1619 in a solovent free system were investigated. The esterification degree was increased greatly through dehydrating during the reaction and the amount of lauric acid added was more than that of the stoichiometric ones and the yield of product was further improved by fed batch feeding of PEG 400 . In the reaction system that composed of 5 0 mmol lauric acid, 2 5 mmol PEG 400 , 20mg immobilized lipase(200u), 0 2 ml water, at 40℃ shaken for 48h in 100 ml conical flask without plug, the esterification degree of 91% was obtained, when a vacuum was applied to the vessel during the reaction, the esterification degree of 98.9% was reached. When the amount of lauric acid used was increased to 60 mmol, the PEG 400 in reaction system was completely esterified. The recovery yield of product was 95% by hexane extracting and the esterified product was identified as diester by means of TLC.更多还原