有机溶剂/缓冲液两相体系中全细胞催化拆分环氧氯丙烷  

Enzymatic resolution of epichlorohydrin catalyzed by whole cells in an organic solvent/buffer biphasic system

作　　者：邹树平[1] 颜海蔚[1] 胡忠策[1] 郑裕国[1] 

机构地区：[1]浙江工业大学生物工程研究所,浙江杭州310014

出　　处：《催化学报》2013年第7期1339-1347,共9页

基　　金：国家重点基础研究发展计划(973计划;2011CB710806);国家自然科学基金(21176224);高等学校博士学科点专项科研基金(新教师类;2012331712004)~~

摘　　要：研究了有机溶剂/缓冲液两相体系中重组大肠杆菌E.coliBL21(DE3)全细胞水解动力学拆分外消旋环氧氯丙烷制备(R)-环氧氯丙烷的过程.结果表明,最适反应条件为:最适有机溶剂异辛烷与缓冲液的体积比7:3,最适缓冲液pH8.0,底物浓度574mmol/L,全细胞加入量0.07g湿菌体/ml溶液,温度30oC.在此条件下于1L反应器中反应45min,(R)-环氧氯丙烷的摩尔产率、光学纯度和时空产率分别达到37.5%,99.3%ee和0.286mol/(L·h).与单一水相体系相比,异辛烷/缓冲液两相体系中底物浓度和(R)-环氧氯丙烷时空产率分别提高了55.2%和98.6%.The biocatalytic resolution of （R,S）‐epichlorohydrin to （R）‐epichlorohydrin by whole cells from a recombinant Escherichia coli BL21（ED3） expressing epoxide hydrolase activity in a series of organic solvent/buffer biphasic systems was studied. Isooctane was found to be the best organic solvent. The optimum volume ratio of the organic phase to the aqueous phase, reaction temperature, pH, substrate concentration, cell concentration, and reaction time were 7：3, 30 ℃, 8.0, 574 mmol/L, 0.07 g/ml wet cells, and 45 min, respectively. Under the optimized conditions, a yield of 37.5% with 99.3% ee and an average productivity of 0.286 mol/（L·h） were obtained in a stirred reactor （1‐L scale）. Thus, the bioconversion was more efficient in the isooctane/buffer biphasic system than that in a monophasic aqueous system, where the substrate concentration and the average productivity of （R）‐epichlorohydrin were improved by 55.2% and 98.6%, respectively.

关 键 词：环氧化物水解酶 全细胞 手性环氧氯丙烷 生物拆分 有机溶剂 缓冲液双相体系 

分 类 号：O643.32[理学—物理化学]