摘要
通过筛选得到不对称还原4-氯乙酰乙酸乙酯(COBE)合成(S)-4-氯-3-羟基丁酸乙酯(S-CHBE)对映选择性好的微生物菌株出芽短梗霉菌(Aureobasidiumpullulans)SW0202.对其还原反应条件进行优化,得到最佳转化条件为:初始细胞浓度0.32g/mL(以湿菌体计),底物浓度20g/L,pH7.0,温度30℃.在此优化条件下,产物浓度达20.32g/L,摩尔转化率为79.6%,产物对映体过量值e.e.为97.8%.分批添加底物可显著减小底物的抑制作用.
Aureobasidium pullulans SW0202 with high enantioselectivity for asymmetric reduction of ethyl 4-chloroacetoacetate （COBE） to ethyl （S）-4-chloro-3-hydroxybutyrate （S-CHBE） was isolated. The asymmetric reduction of COBE to optically active CHBE catalyzed by Aureobasidium pullulans SW0202 in aqueous phase was also investigated. The reduction was conducted in K2HPO4-KH2PO4 buffer, and the concentrations of COBE and CHBE as well as optical purity of the product were determined by capillary gas chromatography （GC） and chiral capillary GC respectively. The results showed that the optimal conditions for the conversion were the initial cell concentration 0.32 g/mL（wet weight）, the initial COBE concentration 20 g/L, pH 7.0 and the temperature 30 ℃. The molar conversion rate reached 79.6% （20.32 g/L CHBE）, with 97.8% e.e. Subsequently the experimental results of batch supplement of substrate indicate that this strategy can greatly reduce substance inhibition.
出处
《过程工程学报》
EI
CAS
CSCD
北大核心
2005年第6期665-669,共5页
The Chinese Journal of Process Engineering
基金
973计划资助项目(编号:2003CB716008)
国家自然科学基金资助项目(编号:20476039)
