微水相中改性Ultrastable-Y分子筛固定化脂肪酶拆分(R,S)-2-辛醇

采用改性Ultrastable-Y分子筛固定化P. expansum PED-03脂肪酶(PEL), 利用固定化PEL在微水相中对(R,S)-2-辛醇进行拆分. 结果表明, 改性Ultrastable-Y分子筛固定化PEL所催化的拆分反应的转化率(c)和对映体过量值(e.e.)以及对映体选择性(E)均得到大幅度提高. 介质类型和体系含水量对酶促拆分反应有较大的影响. 在以正己烷为溶剂, 含水量为0.8%的体系中, 于50 ℃反应24 h的转化率(c)可达到理论值的97.68%, 对映体过量值(e.e.)可达到98.75%. 改性Ultrastable-Y分子筛固定化PEL催化效率高、立体选择性强, 且催化性能稳定, 在(R,S)-2-辛醇的酶法拆分方面具有良好的应用前景.

Enzymatic Resolution of (R,S)-2-Octanol by Ultrastable-Y Molecular Siver Immobilized-lipase in Microaqueous Media

The resolution of (R,S)-2-octanol was performed in microaqueous media by P. expansum PED-03 lipase(PEL) immobilized onto Ultrastable-Y modified molecular sieve. It was found that conversion(c), enantiomeric excess(e.e.), and enantioselectivity(E) of the reaction catalyzed by PEL immobilized onto Ultrastable-Y modified molecular sieve were much higher, compared with free PEL and PEL immobilized by other carriers. Media type and water content played an important role in the resolution of (R,S)-2-octanol catalyzed by Ultrastable-Y modified molecular sieve immobilized-PEL, and the reaction conversion(c) reached 97.68% of the theoretical value and the enantiomeric excess(e.e.) reached 98.75% in n-hexane with 0.8% water at “memorial” pH =9.5 and 50 ℃ for 24 h. The modified Ultrastable-Y molecular sieve immobilized-PEL was a good biocatalyst with a fine enantioselectivity and stability, presenting a good promise in the enzymatic resolution of (R,S)-2-octanol.