设计制备出比表面积290.6 m2/g、平均孔径和孔体积16.5 nm和1.66 cm3的功能化介孔载体G-NH2-MCF, G-NH2-MCF共价结合假单胞菌脂肪酶( Pseudomonas sp Lipase,PSL),获得了固定化酶PSL/G-NH2-MCF。在甲苯溶剂中,乙酸乙烯酯作酰化剂,固定化酶PSL/G-NH2-MCF催化( R,S)-3-羟基丁酸乙酯的转酯化拆分反应,转化率为15.6%,(S)-3-羟基丁酸乙酯的对映体过量值(eeS)为17.8%,(R)-3-乙酸基丁酸乙酯对映体过量值(eeP)为96.2%,对映选择性参数E为61；而在相同条件下,使用游离酶PSL催化拆分反应,转化率、eeS、eeP和E值分别为2.16%,1.95%,88.2%和16,PSL经G-NH2-MCF固定化后催化性能得到明显提高。同时研究了固定化酶PSL/G-NH2-MCF催化( R,S)-3-羟基丁酸乙酯转酯拆分的反应条件对转化率和对映选择性的影响规律。%Functionalized mesoporous support G-NH2-MCF with specific surface area of 290. 6 m2/g,av-erage pore diameter of 16. 5 nm and pore volume of 1. 66 cm3 was prepared. The Pseudomonas sp lipase PSL was immobilized covalently on G-NH2-MCF materials to prepare the immobilized enzyme PSL/G-NH2-MCF. The PSL/G-NH2-MCF catalyzed transesterification resolutionin of ( R,S)-ethyl-3-hydroxybu-tyrate with vinyl acetate as acylation agent in toluene,17. 8% enantiomeric excess (eeS) of (S)-ethyl-3-hydroxybutyrate,96. 2% enantiomeric excess (eeP) of (R)-ethyl-3-acetroxybutyrate,and conversion of 15. 6% with 61 enantiomeric ratio were obtained. While using free PSL in the resolution reaction under the same conditions,the eeS,eeP,the conversion and enantiomeric ratio E were 1. 95%,88. 2%,2. 16%and 16,respectively,which means that the activity and enantioselectivity of PSL are improved significantly by the immobilization on G-NH2-MCF. The effects of the reaction conditions on the conversion and enanti-oselectivity of PSL/G-NH2-MCF for the transesterification resolutionin were studied.
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