文献类型：期刊文献

英文题名：Efficient production of (R)-(-)-mandelic acid in biphasic system by immobilized recombinant E. coli

作者：Ni, Kefeng[1];Wang, Hualei[1];Zhao, Li[1];Zhang, Minjie[1];Zhang, Siyuan[1];Ren, Yuhong[1];Wei, Dongzhi[1]

机构：[1]E China Univ Sci & Technol, New World Inst Biotechnol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2013

卷号：167

期号：4

起止页码：433

外文期刊名：JOURNAL OF BIOTECHNOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000324737900011)】；

基金：This work was funded by the National Natural Foundation of China (No. 21076079), Open Funding Project of the State Key Laboratory of Bioreactor Engineering, the Fundamental Research Funds for the Central Universities and National Major Science and Technology Projects of China (No. 2012ZX09304009).

语种：英文

外文关键词：Immobilization; Catecholic chitosan; (R)-(-)-mandelic acid; Nitrilase; Biphasic reaction

摘要：The recombinant Escherichia coli M15/BCJ2315 which harbored a mandelonitrilase from Burkholderia cenocepacia J2315 was immobilized via catecholic chitosan and functionalized with magnetism by iron oxide nanoparticles. The immobilized cells showed high activity recovery, enhanced stability and good operability in the enantioselective hydrolysis of mandelonitrile to (R)-(-)-mandelic acid. Furthermore, the immobilized cells were reused up to 15 cycles without any activity loss in completely hydrolyzing mandelonitrile (100 mM) within 1 h in aqueous solution. The ethyl acetate-water biphasic system was built and optimized. Under the optimal conditions, as high as 1 M mandelonitrile could be hydrolyzed within 4 h with a final yield and ee value of 99% and 95%, respectively. Moreover, the successive hydrolysis of mandelonitrile was performed by repeated use of the immobilized cells for 6 batches, giving a final productivity (g L-1 h(-1)) and relative production (g g(-1)) of 40.9 and 38.9, respectively. (c) 2013 Elsevier B.V. All rights reserved.