中文摘要：

实验研究了表面活性剂（SDS,CTAB,Emulsifier OP-6）对面包酵母细胞催化2-辛酮不对称还原反应的影响.结果表明,当底物浓度为10mmol/L时,在不含表面活性剂的体系中,副反应和逆反应使反应96h后的得率和产物（S）-2-辛醇对映体过量率（Enantiomeric Excess,e.e.）仅为77.4%和78.8%.一定浓度的表面活性剂可提高正反应速率、降低逆反应和副反应速率,在含0.4mmol/L Emulsifier OP-6或0.04mmol/L CTAB的体系中反应96h,得率分别达到88.4%和91.1%,产物e.e.值为97.0%和94.5%.反应得率和产物e.e.值提高与表面活性剂对细胞生长、细胞膜透性的改变有关.EmulsifierOP-6的作用效果优于其他2种表面活性剂.

英文摘要：

In aqueous buffer system containing surfactants of SDS,CTAB and Emulsifier OP-6,the asymmetric reduction of 2-octanone to（S）-2-octanol with Saccharomyces cerevisiae cells was studied.The results indicated that the yield and product e.e.were disappointingly low due to the serious reverse reaction and side reaction in the surfactant-free system.Particularly,at the substrate concentration of 10 mmol/L,they were 77.4% and 78.8% for 96 h reaction.With addition of surfactants to the system,the rates of reverse and side reactions were decreased by Emulsifier OP-6 and CTAB,with the effective increase of the average positive reaction rate.In the systems containing 0.4 mmol/L Emulsifier OP-6 or 0.04 mmol/L CTAB,the yield and e.e.value were 88.4%,91.1% and 97.0%,94.5%,respectively,obviously higher than those in the reaction system without surfactant.The further work showed that the enhancement of efficiency and enantioselectivity of the asymmetric reduction resulted from the effect of the surfactants on the cell characteristics such as growth,membrane penetrability,etc.Among the surfactants investigated,Emulsifier OP-6 performed best.