应用化学2011，Vol.28Issue(4)：426-431,6.DOI:10.3724/SP.J.1095.2011.00237
十六烷基三甲基溴化铵/山梨醇酐硬脂酸酯微乳液凝胶固定化脂肪酶的催化活性及立体选择性
The Catalytic Activity and Stereoselectivity of Lipase Immobilized in Cetyl Trimethyl Ammonium Bromide/Sorbitan Monostearate Microemulsion-based Gel
摘要
Abstract
Cetyl trimethyl ammonium bromide/sorbitan monostearate ( Span-60) microemulsion-based gel (CTAB/Span-60 MBG) having good stability in aqueous solution was successfully prepared. The mass percentage of Span-60 in emulsifier mixture( EM, the mixture of n-butanol and Span-60) was determined. The catalytic activity and stereoselectivity of lipase immobilized in CTAB/Span-60 MBG were tested using the esterification of hexanoic acid and hexanol, the hydrolysis of α-glyceryl monostearate and the stereoselective esterification of racemic ibuprofen and octanol as probes, respectively. The results showed that CTAB/Span-60 MBG with good mechanical strength could be achieved when the mass percentage of Span-60 in EM was less than 57％. In organic solvent, the catalytic esterification activity of lipase in this MBG increased gradually with the increase of the content of Span-60 in EM at the first stage and reached maximum at 35％ and then decreased slightly with further increase of the content, and was higher than that in CTAB MBG, within the investigated content of Span-60. This immobilized lipase could catalyze the hydrolysis of α-glyceryl monostearate in aqueous solution and the reaction conversion rate didn't change any more after 24 h. The catalytic hydrolytic activity decreased by 13. 68％ after 9 re-usage times. This suggests that lipase in CTAB/ Span-60 MBG could be separated and reused. Lipase in this MBG also selectively catalyzed S-enantiomer ibuprofen to S-enantiomer ester and the excessive enantiomeric product(eee) of the latter gradually decreased with the proceeding of the reaction, but showing better stereoselectivity than CTAB MBG. As a promising carrier for immobilizing lipase, CTAB/Span-60 MBG could be used in biosynthesis and biotransformation not only in organic solvent but also in aqueous solution.关键词
微乳液凝胶/固定化脂肪酶/催化活性/立体选择性/反应转化率/对映体过量值Key words
microemulsion-based gel ( MBG ) , immobilized lipase, catalytic activity, stereoselectivity, reaction conversion rate, enantiomeric excess (eee)分类
化学化工引用本文复制引用
王晶,宋少芳,路福绥..十六烷基三甲基溴化铵/山梨醇酐硬脂酸酯微乳液凝胶固定化脂肪酶的催化活性及立体选择性[J].应用化学,2011,28(4):426-431,6.基金项目
国家自然科学基金(20803044)和山东省自然科学基金(ZR2009DM032)资助项目 （20803044）
