Kinetics of acetophenone reduction to ( R )-1-phenylethanol by a whole-cell Pichia capsulata biocatalyst.

(R)-1-phenylethanol is an important substance in fragrance and flavor industry. In this work, the reduction of acetophenone to (R)-1-phenylethanol in an aqueous medium was examined usingPichia capsulataas a whole-cell biocatalyst. Progress curve and initial rate measurements were used to obtain kinetic data. The experiments were carried out at pH 5, temperature of 25 °C, and in the presence of glucose to maintainin vivoregeneration of NADH. A model of the reversible reaction kinetics considering the substrate inhibition of the forward reaction was developed. Five kinetic parameters of this model were determined by a simultaneous fit of a reaction rate dependence on substrate concentration and 18 substrate and product concentration progress curves with very good accuracy. Equilibrium constant of the reaction and equilibrium conversion of acetophenone to (R)-1-phenylethanol were 13.7 and 93%, respectively. [ABSTRACT FROM PUBLISHER]