文献类型：期刊文献

英文题名：Biocatalytic synthesis of (R)-(2)-mandelic acid from racemic mandelonitrile by cetyltrimethylammonium bromidepermeabilized cells of Alcaligenes faecalis ECU0401

作者：He, Yu-Cai[1,2]; Zhang, Zhi-Jun[1]; Xu, Jian-He[1]; Liu, You-Yan[3]

机构：[1] Laboratory of Biocatalysis and Bioprocessing, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; [2] College of Chemistry and Chemical Engineering, Jiangsu Polytechnic University, Changzhou 213164, China; [3] College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, Guangxi, China

年份：2010

卷号：37

期号：7

起止页码：741

外文期刊名：Journal of Industrial Microbiology and Biotechnology

收录：EI(收录号：20242616538004)

语种：英文

外文关键词：Cell immobilization - Enzyme immobilization - Hydrolysis - Organic acids - Radioactive waste vitrification

摘要：The nitrilase from Alcaligenes faecalis ECU0401 belongs to the category of arylacetonitrilase, which could hydrolyze 2-chloromandelonitrile, 3,4-dimethoxyphenylacetonitrile, mandelonitrile, and phenylacetonitrile into the corresponding arylacetic acids. To overcome the permeability barrier and prepare whole cell biocatalysts with high activities, permeabilization of Alcaligenes faecalis ECU0401 in relation to nitrilase activity was optimized by using cetyltrimethylammonium bromide (CTAB) as permeabilizing agent. The nitrilase activity from Alcaligenes faecalis ECU0401 increased 4.5- fold when the cells were permeabilized with 0.3% (w/v) CTAB for 20 min at 25°C and pH 6.5. Consequently, almost all the mandelonitrile was consumed and converted to (R)-(-)-mandelic acid with greater than 99.9% enantiomeric excess (e.e.) by the CTAB-permeabilized cells. The permeability barrier has been significantly reduced in the hydrolysis of mandelonitrile by using CTABpermeabilized cells and a dynamic resolution was successfully achieved, giving a 100% theoretical yield of (R)-(-)-mandelic acid. Efficient biocatalyst recycling was achieved as a result of cell immobilization in calcium alginate, with a product-to-biocatalyst ratio of 3.82 g (R)-(-)-mandelic acid g-1 dry cell weight (dcw) cell after 20 cycles of repeated use. ? Society for Industrial Microbiology 2010.