OXIDATIVE DAMAGE OF PROTEIN-INDUCED BY THE AMADORI COMPOUND COPPER-ION SYSTEM

Generation of oxygen radicals from the browning solution of glucose and amino acids in the presence of copper ion and their oxidative action on protein were investigated in detail. Reaction mixtures of the browning solution, bovine serum albumin (BSA) and copper(II), incubated for 24 h at 40 °C under aerated conditions markedly accelerated the oxidative depolymerization of BSA and the oxidative degradation of its histidine residue. Among the many amino acids used in these browning solutions, β-alanine, 4-aminobutyric acid, and 6-aminocaproic acid containing solutions exhibited very high activities for oxidative degradation of N-benzoyl-L-histidine (Bz-His). The active product in the browning solution of glucose and β-alanine was estimated to be an Amadori compound (AC), 1-deoxy-1-β-alanino-D-fructose. © 1990, American Chemical Society. All rights reserved.