Amino Acids Liberated from Nondialyzable Melanoidin by Hydrolysis

Abstract

Amino acids (L-Val, L-Lys·HCl, L-Asp, L-Phe, L-Pro, DL-Met) were heated separately with D-glucose at 120°C, for 120 minutes in homogeneous powder state. The reaction mixtures were dialyze and nondialyzed portions (non-dialyzable melanoidins) were analyzed for amino acids after hydrolysis (6N HCl, 110°C, 18hrs). Considerably large amount of original amino acid and ammonia were found in hydrolysates. Thus, it was assumed that non-dialyzable melanoidin contained original amino acids, amino-radicals formed through deamination and acid amides presumably formed from oxydized glucose. Other amino acids and ninhydrin-positive substances were detected. IR spectra of non-dialyzable melanoidins were also measured.