文献类型：期刊文献

英文题名：Enhanced Enzymatic Production of Cephalexin at High Substrate Concentration with in situ Product Removal by Complexation

作者：Li, Dengchao[1];Zhang, Yewang[1];Cheng, Shiwei[1];Gao, Qiong[1];Wei, Dongzhi[1]

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

年份：2008

卷号：46

期号：4

起止页码：461

外文期刊名：FOOD TECHNOLOGY AND BIOTECHNOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000261503500016)】；

基金：This work was supported by the Program for New Century Excellent Talents at the University (project no. NCET-04-0411).

语种：英文

外文关键词：cephalexin; complexation; enzymatic synthesis; in situ product removal; penicillin G acylase

摘要：Cephalexin (CEX) was synthesized with 7-amino-3-deacetoxycephalosporanic acid (7-ADCA) and D(-)-phenylglycine methyl ester (PGME) using immobilized penicillin G acylase from Escherichia coli. It was found that substrate concentration and in situ product could remarkably influence the ratio of synthesis to hydrolysis (S/H) and the efficiency of CEX synthesis. The optimal ratio of enzyme to substrate was 65 IU/mM 7-ADCA. High substrate concentration improved the 7-ADCA conversion from 61 to 81 % in the process without in situ product removal (ISPR), while in the synthetic process with ISPR, high substrate concentration increased the 7-ADCA conversion from 88 to 98 %. CEX was easily separated from CEX/beta-naphthol complex and its purity and overall yield were 99 and 70 respectively.