文献类型：期刊文献

英文题名：Enzymatic synthesis of Cephalexin in recyclable aqueous two-phase systems composed by two pH responsive polymers

作者：Li, Shutao[1];Cao, Xuejun[1]

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

年份：2014

卷号：90

起止页码：301

外文期刊名：BIOCHEMICAL ENGINEERING JOURNAL

收录：;EI(收录号：20143017975114);WOS:【SCI-EXPANDED(收录号:WOS:000340989800037)】；

基金：The authors very appreciate financial support from National Natural Science Foundation of China (No. 21376078) and National Special Fund for State Key Laboratory of Bioreactor Engineering (2060204).

语种：英文

外文关键词：Aqueous two phase; Immobilized enzymes; Biocatalysis; Product inhibition; Cephalexin; pH-sensitive polymer

摘要：The synthesis of Cephalexin in novel recyclable aqueous two-phase systems was studied, using immobilized penicillin acylase as biocatalyst, 7-amino-3-desacetoxy cephalosporanic acid (7-ADCA) as nucleophile and phenyl glycine methyl ester (PGME) as acyl donor. The aqueous two-phase system (ATPS) was composed by two pH-response copolymers P-ADBA and P-MDB, which could be recycled efficiently. In the ATPS, high partition coefficient (2.57) for Cephalexin and low partition coefficient (0.21) for 7-ADCA were obtained. Then the synthesis of Cephalexin in ATPS and conventional one-phase system was compared. Higher Cephalexin yield was obtained in ATPS. In addition, synthesis in ATPS was improved at higher substrates concentrations, obtaining yield of 98.2% with 50 mM 7-ADCA and 150 mM PGME at pH 5.8, 20 degrees C. Even reducing acyl donor to nucleophile ratio to 2, the yield can still above 90%. P-ADBA/P-MDB recycling aqueous two-phase system is suitable for synthesis of Cephalexin. (C) 2014 Elsevier B.V. All rights reserved.