文献类型：期刊文献

英文题名：Bio-resolution of a chiral epoxide using whole cells of Bacillus megaterium ECU1001 in a biphasic system

作者：Gong, Peng-Fei[1]; Xu, Jian-He[1]

机构：[1] Lab. Biocatalysis and Bioprocessing, State Key Lab. of Bioreactor Eng., E. China Univ. Sci. Technol., P.O.

年份：2005

卷号：36

期号：2-3

起止页码：252

外文期刊名：Enzyme and Microbial Technology

收录：EI(收录号：2005028778590)

语种：英文

外文关键词：Biocatalysts - Cells - Concentration (process) - Ethers - Optimization - Solubility

摘要：Optically active epoxides can be prepared by kinetic resolution of racemic mixtures using stereospecific epoxide hydrolases. To increase the bio-resolution efficiency of a sparingly water-soluble epoxide (glycidyl phenyl ether, GPE), we investigated the use of organic/aqueous two-phase system. Various conditions were systematically examined and optimized in shake flasks. Isooctane was found to be the most suitable solvent as the organic phase. The phase volume ratio (φo/w) and biocatalyst concentration were shown to be sensitive parameters affecting both the reaction rate and the enzyme enantiospecificity in the biphase system. An isooctane/aqueous system was developed to overcome the low solubility and instability of GPE in the aqueous phase, resulting in a significant improvement of enatiomeric ratio (E-value) from 39.5 to 94.0 and an average productivity of 18.8 mg GPE/(h g) biocatalyst to 48.9 mg GPE/(h g) biocatalyst, respectively. Resolution of a 90.1 g/l solution of racemic glycidyl phenyl ether in isooctane phase was successfully carried out in a mechanically stirred reactor (120 ml), affording (S)-glycidyl phenyl ether in high (100%) enantiomeric excess with a yield of 44.5%. ? 2004 Elsevier Inc. All rights reserved.