Application of membrane phase separation for enzymatic synthesis of aspartame precursor in biphasic reaction system

Abstract

N-(benzyloxycarbonyl)-L-aspartyl-L-phenylalanine methyl ester (ZAPM), an aspartame precursor, was synthesized enzymatically from N-(benzyloxycarbonyl)-L-aspartic acid (ZA) and L-phenylalanine methyl ester (PM) using a biphasic reaction system. Measurement of the partition coefficient in an aqueous/alcohol system showed that, 1-hexanol and 1-heptanol were proper solvents for the system. The membrane phase separation could be performed using a hydrophobic membrane, and 1-hexanol gave higher flux than 1-heptanol. Integration of the membrane phase separation into the biphasic enzyme reaction system was realized by the continuous stable ZAPM production.