磁性固定化青霉素酰化酶催化拆分(R,S)-2-氯苯甘氨酸甲酯  

Enzymatic Resolution of (R,S)-2-Chlorophenyl Glycine Methyl Ester with Magnetically Immobilized Penicillin G Acylase

作　　者：薛屏[1] 谷耀华 张立根[1] 马原[1] 李鹏[1] 

机构地区：[1]宁夏大学省部共建天然气转化国家重点实验室培育基地,宁夏银川750021

出　　处：《石油化工》2014年第11期1284-1289,共6页Petrochemical Technology

基　　金：国家自然科学基金项目(21263020);国家重点基础研究发展计划前期研究专项项目(2012CB723106)

摘　　要：将青霉素酰化酶(PGA)固定于饱和磁化率为6.5 emu/g、富含环氧基的大孔磁性聚合物微球(GM)上,所得磁性固定化酶PGA/GM用于在水相中催化(R,S)-2-氯苯甘氨酸甲酯(2-CGM)发生不对称水解反应;在20℃下反应48 h,所得(S)-2-CGM和(R)-2-氯苯甘氨酸的对映体过量值分别为98.0%和58.8%,底物总转化率为62.5%。PGA经GM固定化后,催化(R,S)-2-CGM水解反应的活性和对映体选择性均有显著提高。PGA/GM具有较强的磁响应性,在外加磁场的作用下能进行快速分离和洗涤,机械损失小;经6次循环使用,其活性和对映体选择性未出现大幅衰减。Penicillin G acylase（PGA） was immobilized on self-made magnetic polymer microspheres（GM） with epoxy groups, macropores and saturation magnetization of 6.5 emu/g to prepare the PGA/GM magnetic immobilized enzyme. The kinetic resolution of racemic （R, S）-2- chlorophenyl glycine methyl ester（2-CGM） through the hydrolysis catalyzed by PGA/GM were investigated. The enantiomeric excess values of （S）-2-CGM and （R）-2-ehlorophenyl glycine were 98.0% and 58.8% respectively, and the conversion of （R, S）-2-CGM were 62.5% in the enzymatic hydrolysis under the conditions of 20 ℃ and 48 h. It was observed that the activity and enantioselectivity of PGA for the asymmetric hydrolysis of （R, S）-2-CGM were improved significantly by the immobilization. The immobilized enzyme could be recovered easily without mechanical loss and considerably kept its initial activity and enantioselectivit7 after it was reused six times.

关 键 词：磁性固定化青霉素酰化酶 (R S)-2-氯苯甘氨酸甲酯 不对称水解反应 酶催化拆分 对映选择性 

分 类 号：TQ426.97[化学工程]