RECOVERY OF L-PHENYLALANINE AND L-ASPARTIC ACID DURING PREPARATION OF .alpha.-L-ASPARTYL-L-PHENYLALANINE METHYL ESTER

摘要

ABSTRACT OF THE DISCLOSUREThere is described an improved process forthe separation and recovery of L-phenylalanine andL-aspartic acid from sidestreams resulting from thepreparation of .alpha.-L-aspartyl-L-phenylalanine methylester. It has been found that superior separation isobtained by combining one or more of the mother liquorand wash solutions formed during the preparation of.alpha.-L-aspartyl-L-phenylalanine methyl ester, hydrolyzingsame to afford the hydrohalide salts of L-aspartic acidand L-phenylalanine, acidifying the hydrolysis solutionto precipitate the hydrohalide salt of L-phenylalanine,separating the hydrohalide salt of L-phenylalanine,dissolving it in water and adjusting the pH of the solu-tion to the isoelectric point of L-phenylalanine, thusaffording pure L-phenylalanine, and thereafter adjustingthe pH of the solution after separation of the L-phenyl-alanine hydrohalide to the isoelectric point of L-asparticacid to precipitate L-aspartic acid.