文献类型：期刊文献

英文题名：Preparation of (R)-(-)-mandelic acid and its derivatives from racemates by enantioselective degradation with a newly isolated bacterial strain Alcaligenes sp. ECU0401

作者：He, Yu-Cai[1]; Xu, Jian-He[1]; Pan, Jiang[1]; Ouyang, Li-Ming[1]; Xu, Yi[1]

机构：[1] Laboratory of Biocatalysis and Bioprocessing, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China

年份：2008

卷号：31

期号：5

起止页码：445

外文期刊名：Bioprocess and Biosystems Engineering

收录：EI(收录号：20083011398496)

语种：英文

外文关键词：Organic acids - Enantiomers - Batch cell culture

摘要：An enantioselective mandelate-degrading bacterium, Alcaligenes sp. ECU0401, was newly isolated from soil. By fed-batch culture, (R)-(-)-mandelic acid was successfully prepared in a 5-L fermenter with 32.8% isolated yield and >99.9% enantiomeric excesses (e.e.) from totally 3.04% (w/v) of racemic mandelic acid after 99 h of biotransformation. The optimal reaction pH and temperature were 6.5 and 30C, respectively. Using the resting cell as a biocatalyst for asymmetric degradation of racemic mandelic acid and chloro-substituted derivatives thereof, (R)-(-)-mandelic acid, (R)-(-)-o-chloromandelic acid, (S)-(+)-m-chloromandelic acid and (S)-(+)-p-chloromandelic acid were recovered with high analytic yields and excellent enantiomeric excesses (e.e. > 99.9%). (R)-(-)-Mandelic acid could also be obtained after 12 h of biotransformation with 41.5% isolated yield and >99.9% e.e. ? 2007 Springer-Verlag.