Production of (S)-(+)-3-Hydroxybutyric Acid from 1, 3-Butanediol by Resting Cells of Yeasts

Abstract

Various yeast strains were screened for production of 3-hydroxybutyric acid (3-HBA) from 1, 3-butanediol (1, 3-BD) by a resting cell system. Many yeasts were found to oxidize 1, 3-BD to 3-HBA. Among them, Hansenula anomala IFO 0195 produced (S)-(+)-3-HBA of the highest optical purity. Reaction temperature and addition of glucose were significantly effective on the optical purity and production of the acid. When resting cells of the strain were incubated at 27°C in an optimal reaction mixture containing 60.0mg/ml 1, 3-BD, 2.0% CaCO₃, and 1.0% glucose, 26.7 mg/ml of 3-HBA were produced with 88% enantiomer excess for 2 days. Dominant accumulation of (S)-(+)-3-HBA might be due to enantioselective degradation of (R)-(-)-3-HBA, though both (S)-(+)-and (R)-(-)-1, 3-BD are oxidized by the strain.