文献类型：期刊文献

英文题名：Enzymatic Production of l-Menthol by a High Substrate Concentration Tolerable Esterase from Newly Isolated Bacillus subtilis ECU0554

作者：Zheng, Gao-Wei[1];Yu, Hui-Lei[1];Zhang, Jian-Dong[1];Xu, Jian-He[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Lab Biocatalysis & Bioproc, Shanghai 200237, Peoples R China

年份：2009

卷号：351

期号：3

起止页码：405

外文期刊名：ADVANCED SYNTHESIS & CATALYSIS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000264058900020)】；

基金：This work was financially supported by National Natural Science Foundation of China (grant nos. 20506037 and 20672037) and Ministry of Science and Technology, P R. China (grant nos. 2006AA02Z205 and 2007AA02Z225).

语种：英文

外文关键词：Bacillus subtilis esterase; enzyme catalysis; high substrate concentration tolerance; hydrolysis; l-menthol; dl-menthyl acetate

摘要：Enzymatic preparation of l-menthol has been attracting much attention in the flavor and fragrance industry. A new ideal strain, Bacillus subtilis ECU0554, which exhibited high hydrolytic activity and excellent enantioselectivity towards l-menthyl ester, has been successfully isolated from soil samples through enrichment culture and identified as Bacillus subtilis by 16S rDNA gene sequencing. The esterase extracted from B. subtilis ECU0554 (BSE) showed the best catalytic properties (E > 200) for dl-menthyl acetate among the five menthyl esters examined. Enantioselective hydrolysis of 100 mM dl-menthyl acetate at 30 degrees C and pH 7.0, using crude BSE as biocatalyst and 10% ethanol (v/v) as cosolvent, resulted in 49.0% conversion (3 h) and 98.0% ee for the l-menthol produced, which were much better than those using commercial enzymes tested. Moreover, BSE exhibited strong tolerance against high substrate concentration (up to 500 mM), and the concentration of l-menthol produced could reach as high as 182 mM, and more importantly, the optical purity of l-menthol produced was kept above 97% ee, which were not found in previous reports. These results imply that BSE is a potentially promising biocatalyst for the large-scale enzymatic preparation of l-menthol. Using this excellent biocatalyst, the enzymatic production of l-menthol will become a mild, efficient, inexpensive and easy-to-use "green chemistry" methodology.