利用酿酒酵母静息细胞转化合成2-苯乙醇,确定了静息细胞转化菌龄、转化液缓冲液体系和辅酶NADH再生辅助底物.在单因子试验基础上,用Plackett-Burm设计从影响转化6个因素中筛选出影响细胞转化的显著因素:辅助底物乙醇质量浓度、转化液pH和转化温度,以Box-Benhnken试验设计结合响应面法分析确定显著因子的最优水平.结果表明,最佳转化条件为乙醇质量浓度16.5 g/L、pH 5.1、转化温度26℃,2-苯乙醇产量为3.49 g/L(转化率58.8％),比优化前提高了49.14％,静息细胞重复使用8次,2-苯乙醇产量无明显下降.转化液中加入10％的大孔吸附树脂对产物进行原位产物吸附,转化40 h,2-苯乙醇总质量浓度迭9.34 g/L,L-苯丙氨酸转化率为83.9％,产量比未加入大孔树脂提高了171.5％.%The bioconversion conditions on the production of 2-phenylethanol with Saccharomyces cerevisiae resting cell were optimized.Incubation time of resting cell,buffer solution and co-substrate of coenzyme NADH regeneration were determined.Based on the results of single factor test and Plackett-Burm design,three factors including concentration of co-substrate ethanol,pH and reaction temperature were picked out as prominent factors affecting bioconversion of 2-phenylthanol.The optimal bioconversion conditions were determined by Box-Benhnken design and response surface analysis,i.e.,ethanol concentration 16.5 g/L,pH 5.1,temperature 26 ℃,The yield of 2-phenylethanol reached 3.49 g/L,increased by 49.14％ compared with the original condition.The cell could maintain their bioconversion activity in repeated utilization at least eight times.After 40 h bioconversion,9.34 g/L of 2-phenylethanol and 83.9％ of transformation ratio were obtained under the condition of adding 10％ macroporous resin in situ product removal,the yield of 2-phenylethanol increased 171.5％
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