摘要
以戊二醛活化后的聚脲多孔材料为载体固定荧光假单胞菌脂肪酶,将得到的固定酶用于催化(R,S)-1-苯乙醇和乙酸乙烯酯酯交换反应,反应过程中副产物乙醛对脂肪酶的催化活性和立体选择性会产生抑制作用。考察了乙醛存在下乙醛浓度、反应溶剂、反应温度对酶催化能力的影响。结果表明,乙醛存在下脂肪酶的催化活性和选择性受到明显抑制。当乙醛浓度为0.025 mol/L时,以正己烷为溶剂,40℃下利用固定酶催化(R,S)-1-苯乙醇与乙酸乙烯酯的酯交换反应,此时酶的催化活性和选择性受到的抑制最小。重复使用5次后,体系转化率由第一次49.3%下降至19.4%,对映体选择率下降至26%,表明乙醛的存在加速了酶活性的损失。
Lipase from pseudomonas fluorescenson was immobilized on a polyurea porous material activated by glutaraldehyde as carrier,and the resulting immobilized enzyme was used to catalyze the ester exchange reaction between(R,S)-1-phenylethanol and vinyl acetate.During the reaction process,the byproduct acetaldehyde inhibits the catalytic activity and stereoselectivity of lipase.This paper investigates the effects of acetaldehyde concentration,reaction solvent,and reaction temperature on the catalytic ability of enzymes in the presence of acetaldehyde.The results showed that the catalytic activity and selectivity of lipase were significantly inhibited in the presence of acetaldehyde.When the concentration of acetaldehyde is 0.025 mol/L,using n-hexane as the solvent,and the immobilized enzyme is used to catalyze the ester exchange reaction between(R,S)-1-phenylethanol and vinyl acetate at temperature 40℃.This moment,the catalytic activity and selectivity of the enzyme are least inhibited.After 5 reuse cycles,the system conversion decreased from 49.3%in the first time to 19.4%,and the enantioselectivity decreased to 26%,indicating that the presence of acetaldehyde accelerated the loss of enzyme activity.
作者
周亚梅
刘佳
王欣巧
马世蓉
Zhou Yamei;Liu Jia;Wang Xinqiao;Ma Shirong(Chongqing Chemical Industry Vocational College,Chongqing 401228,China)
出处
《山东化工》
CAS
2024年第6期45-47,51,共4页
Shandong Chemical Industry
基金
重庆化工职业学院校级科研课题(HZY2022-KJ06)。
关键词
乙醛
固定酶
催化活性
立体选择性
acetaldehyde
immobilized enzyme
catalytic activity
enantioselectivity
