Candida parapsilosis with high stereo-selectivity and yield was suitable catalyst for optical chiral phenyl alcohol production and available to scale up. Scale up of process for (S)-phenylethylene glycol production was studied including the preparation of biocatalysts and stereoinversion process. With the same air volume and end linear velocity of stirrer, low pH of fermentation broth and low catalytic performance was achieved while biomass increased to 65 g/L. Based on analysis of organic acids in fermentation broth, optimization of carbon-nitrogen ratio and regulation of dissolved oxygen was applied and biocatalyst with high catalytic performance and biomass was obtained in 150 L fermentor. The stereoinversion was successfully applied in 50 L reactor with optical purity more than 99.4% e. E. And yield more than 95.2% .%近平滑假丝酵母催化立体异构反应制备光学纯手性芳基醇立体选择性和转化效率高,具有良好工业化放大价值.本研究以Candida parapsilosis CCTCC M203011催化外消旋苯基乙二醇立体异构反应制备(S)-苯基乙二醇为对象考察中试规模下生物催化剂制备和生物转化反应过程.研究发现,按照等通风量和等搅拌桨末端速度为基准进行生物催化剂制备规模放大后,菌体浓度提高至65 g/L,但发酵终了pH下降为2.7,异常产酸,并丧失催化特性.在发酵产酸分析基础上,运用发酵培养基组成、恒pH发酵、发酵溶氧控制等策略,在最优条件下,实现了150 L罐催化剂的高效制备,并成功实现50 L反应釜的转化放大,产物(S)-苯基乙二醇e.e.＞99.4％,产率＞95.2％.
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