ENZYMATIC-SYNTHESIS OF D-P-HYDROXYPHENYLGLYCINE FROM DL-P-HYDROXYPHENYLHYDANTOIN IN THE PRESENCE OF ORGANIC COSOLVENT

Bacterial strain KBEL 101 isolated from soil was immobilized within polyacrylamide gel and used for the synthesis of D-p-hydroxyphenylglycine from DL-5-substituted hydantoin. The optimum reaction conditions for immobilized whole cell enzyme were pH 8.0 and temperature 30-degrees-C. Various water-miscible organic solvents were tested with respect to both the activity and the stability of whole cell enzyme, and 5% dimethylsulfoxide (DMSO) was chosen to be a proper solvent: hydantoinase activity increased twofold in the presence of 5% DMSO. From a practical standpoint, it is advantageous to obtain the highest conversion yield, and enzymatic synthesis of N-carbamoyl-D-p-hydroxyphenylglycine was carried out in repeated batch operation in the presence of 5% DMSO. The time required to reach 99% conversion yield was increased with increasing number of batch operations when batch operation was conducted four times.