酵母静息细胞催化丙酮酸乙酯不对称还原制(S)-乳酸乙酯  

Asymmetric Reduction of Ethyl Pyruvate Catalyzed by Yeast Resting Cells to (S)-Ethyl Lactate

作　　者：王丹[1,2] 张强[2] 李旺[2] 戚南昌[3] 郭春晓[1] 杨志荣[1] 张杰[1] 

机构地区：[1]四川大学生命科学学院,四川成都610065 [2]成都医学院生物医学系,四川成都610083 [3]成都医学院医学检验系,四川成都610083

出　　处：《催化学报》2011年第6期1035-1039,共5页

基　　金：四川省科技厅项目(2010GZ0164)~~

摘　　要：从污水处理池及其附近土壤中分离到36株可将丙酮酸乙酯不对称还原成(S)-乳酸乙酯的菌株,经多次复筛,最终得到一株具有较高催化活性的酵母菌BTY18-6.以BTY18-6的静息细胞为催化剂,在水相中进行丙酮酸乙酯不对称还原成(S)-乳酸乙酯的反应,并对反应条件进行了优化.结果表明,以2.5%葡萄糖为辅助底物,反应体系初始pH=6.8,发酵培养48h的菌体湿度0.175g/ml,丙酮酸乙酯初始浓度65mmol/L,于32oC反应48h的条件下,丙酮酸乙酯转化率达95.5%,产物对映体过量值(ee值)为92.1%.Thirty six strains that exhibited the catalytic activity for asymmetric reduction of ethyl pyruvate to （S）-ethyl lactate were isolated from sewage of a chemical factory in Chengdu,China and the neighboring soil.Among them,yeast strain BTY18-6 has high catalytic activity.The asymmetric reduction of ethyl pyruvate to （S）-ethyl lactate catalyzed by BTY18-6 resting cells in an aqueous phase was examined,and the parameters influencing the bio-reduction were optimized.The results showed that,under the optimized conditions of 2.5% glucose as co-substrate,the initial reaction pH=6.8,the initial cell concentration at 0.175 g/ml （wet mass） cultured for 48 h,the initial ethyl pyruvate concentration at 65 mmol/L,temperature 32 oC,and reaction time 48 h,the ethyl pyruvate conversion reached 95.5% with enantiomeric excess of 92.1%.

关 键 词：酵母静息细胞 生物催化 丙酮酸乙酯 不对称还原 (S)-乳酸乙酯 

分 类 号：TQ225.241[化学工程—有机化工]