Abstract

The biocatalysts for asymmetric reduction of aromatic ketones were successfully screened from soil samples polluted by substituted acetophenones. 12 strains could asymmetrically reduce acetophenone into phenethanol, while only strain YS62 possessed the best performance of reducing acetophenone into (S)-1-phenethanol. It was identified as Rhodotorula mucilaginosa based on phenotypic and genetics characteristics and it was used for further asymmetric reduction experiments of acetophenone as a new biocatalyst. R. mucilaginosa YS62 whole-cells could catalyze the asymmetric reduction of acetophenone (35 mM) into (S)-1-phenethanol (31.4 mM) with a conversion rate of 89.7% and enantiomeric excess (e.e.) of 99.9% under 60 g/L YS62 cell, pH 6.5 , 34°C for 30 h and 2% glucose as a co-substrate. These results have shown that R. mucilaginosa YS62 is a promising biocatalyst for the production of optically active phenylethanol derivatives.

Key words: Asymmetric reduction, acetophenone, Rhodotorula mucilaginosa.