The utilization of hydrophilic ionic liquids to improve the synthesis of enantiopure alcohols was successfully performed, via the anti-Prelog asymmetric reduction of ketones with whole cells of Acetobacter sp. CCTCC M209061 newly isolated from Chinese kefir. The best results were obtained with C2OHMIM center dot NO3, which showed good biocompatibility and also increased moderately cell membrane permeability, thus improving the reaction efficiency. Additionally, the optimal C2OHMIM center dot NO3 content, buffer pH, reaction temperature and substrate concentration for 4-(trimethylsilyI)-3-butyn-2-one reduction to (R)-4-(trimethylsilyl)-3-butyn-2-ol were 10.0% (v/v), 5.0, 30 degrees C and 12 mM, respectively. Under the optimized conditions, the initial reaction rate, the maximum yield and the product e.e. were 14.0 mu mol/min.g(cell), 91%, and > 99%, respectively, which were much better than the results reported previously. The efficient whole-cell biocatalytic process proved to be feasible on a 400-mL preparative scale, and the immobilized cells still retained above 88.0% of their original activity after successive re-use for 10 batches, showing the good operational stability in the presence of C2OHMIM center dot NO3. Furthermore, the established biocatalytic system with Acetobacter sp. CCTCC M209061 and C2OHMIM center dot NO3 was shown to be highly effective for the anti-Prelog asymmetric reduction of other aryl ketones to the corresponding (R)-alcohols. (C) 2012 Elsevier Ltd. All rights reserved.