Highly selective resolution of racemic 1-phenyl-1,2-ethanediol by a novel strain Kurthia gibsonii SC0312.

Chiral 1-phenyl-1,2-ethanediol (PED) performs vital effect for the preparation of pharmaceuticals, agrochemicals and cosmetics. In the study, a newly isolated strain Kurthia gibsoniiSC0312 with the ability to selectively oxidize racemic PED to achieve (S)-PED was evaluated in the aqueous reaction system. The strain showed excellent catalytic performances within the range of pH 5·5-8·5, temperature 25-45°C and the amount of cell 15 mg ml-1 to 30 mg ml-1 . Besides, 2-hydroxyacetophenone (HAP) as the oxidation product displayed a stronger inhibition to the catalytic activity of cell, only remaining <63% of catalytic activity after incubation at 40 mmol l-1 HAP for 6 h. For various metal ions, Cu2+ can obviously improve 1·7 times of the catalytic activity of cell at the concentration of 0·2 mmol l-1 . Acetone can stimulate the catalytic capacity of cell to improve the optical purity of (S)-PED at the PED concentration of 80 mmol l-1 , up to appropriately 94% from 85·4%; compared to the resting cell, growing cell exerted no positive effect in the yield and optical purity. Finally, a highly effective kinetic resolution system of racemic PED by the new strain was obtained, with the (S)-PED yield of 41% and optical purity of 94%. SIGNIFICANCE AND IMPACT OF THE STUDY: Biocatalyst is a vital component in the process of biotransformation. There are a growing number of studies of biocatalyst reporting the preparation of enantiomer of 1-phenyl-1,2-ethanediol. And the performance of this preparation reaction is also gradually improving. This study is the first to demonstrate that Kurthia gibsonii can efficiently and selectively oxidize racemic 1-phenyl-1,2-ethanediol, and we assess the effect of various factors on the catalytic performance of the strain. The work adds to a growing body of evidence for using biocatalytic method in the synthesis of chiral 1-phenyl-1,2-ethanediol and provides a probable approach to mine excellent properties of enzymes.