Production of l -Phenylalanine from trans -Cinnamic Acid with Rhodotorula glutinis Containing l -Phenylalanine Ammonia-Lyase Activity

Abstract

An enzymatic method using l -phenylalanine ammonia-lyase (EC 4.3.1.5) for the rapid conversion of trans -cinnamic acid to l -phenylalanine has been investigated. With Rhodotorula glutinis , enzyme activity as high as 0.3 U/ml of culture broth was obtained. The enzyme activity was kept stable for a relatively long time during cultivation by the addition of l -isoleucine. Optimization of the parameters of the conversion reaction resulted in accumulation of 18 mg of l -phenylalanine per ml of reaction mixture. The conversion yield from trans -cinnamic acid was about 70%. The method may provide a rapid and practical way to produce l -phenylalanine useful as an essential amino acid.