Abstract: A strain capable of reducing ethyl-2-oxo-4-phenylbutanoate (OPBE) into ethyl (R)-2- hydroxy-4-phenylbutyrate [(R)-HPBE] was screened and identified as Rhodotorula mucilaginosa. In an isooctane /organic solvent biphasic system，reaction conditions of the asymmetric reduction of OPBE for synthesizing optically active (R)-HPBE with immobilized Rhodotorula mucilaginosa CCZU-G5 cell were investigated. The results showed that the optimum reaction conditions were：ratio of isooctane 10%，concentration of OPBE 100 mmol/L，catalyst dosage 0.45 g/mL and 40 g/L glucose as co-substrate. After 16 h of biotransformation under the optimum conditions，the yield of (R)-HPBE was as high as 83.5% and enantiomeric excess (e.e.). value was more than 99%. These immobilized catalysts could be repeatedly used for seven times，and the yield and e.e. value were all over 70% and 99%，respectively.

Key words: biphasic system, immobilization, Rhodotorula mucilaginosa CCZU-G5, ethyl (R)-2- hydroxy-4-phenylbutyrate, asymmetric reduction

摘要： 通过筛选得到一株高立体选择性还原2-氧代-4-苯基丁酸乙酯（OPBE）合成(R)-2-羟基-4-苯基丁酸乙酯[(R)-HPBE]的菌株并鉴定为黏红酵母。研究了在异辛烷/水两相体系中固定化黏红酵母CCZU-G5不对称还原OPBE合成(R)-HPBE的反应条件。结果表明最适的反应条件为：在异辛烷比例为10%条件下，底物浓度为100 mmol/L，催化剂用量为0.45 g/mL，辅底物为40 g/L的葡萄糖。在建立的反应体系中反应16 h，(R)-HPBE产率最高，达83.5%，e.e.值99%以上。固定化酵母经7次重复使用后，产率和e.e.值分别维持在70%和99%以上。

关键词: 两相体系, 固定化, Rhodotorula mucilaginosa CCZU-G5, (R)-2-羟基-4-苯基丁酸乙酯, 不对称还原