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.