Recovery of l-phenylalanine and l-aspartic acid during preparation of

Abstract

There is described an improved process for the separation and recovery of L-phenylalanine and L-aspartic acid from sidestreams resulting from the preparation of .alpha.-L-aspartyl-L-phenylalanine methyl ester. It has been found that superior separation is obtained by combining one or more of the mother liquor and wash solutions formed during the preparation of .alpha.-L-aspartyl-L-phenylalanine methyl ester, hydrolyzing same to afford the hydrohalide salts of L-aspartic acid and L-phenylalanine, acidifying the hydrolysis solution to precipitate the hydrohalide salt of L-phenylalanine, separating the hydrohalide salt of L-phenylalanine, dissolving it in water and adjusting the pH of the solution to the isoelectric point of L-phenylalanine, thus affording pure L-phenylalanine, and thereafter adjusting the pH of the solution after separation of the L-phenylalanine hydrohalide to the isoelectric point of L-aspartic acid to precipitate L-aspartic acid.