Hydroxyl scavenging activity of glucose, fructose, and ribose-lysine modelMaillard products

Nondialyzable model Maillard reaction products (MRPs) were synthesized by r eacting L-lysine with D-glucose, D-fructose, and D-ribose under different c onditions of reaction time, temperature, pH, and water activity (a(w)). Fiv e experiments common to all three models yielding greater than 0.5g of MRPs were assessed for antioxidant activity. All MRPs exhibited detectable, but variable, non site-specific hydroxyl radical ((OH)-O-.) scavenging activit y (30-90%) in the deoxyribose assay. MRPs derived from a ribose-lysine stud y showed the highest (OH)-O-. scavenging activity (80-90%) in both deoxyrib ose and DNA nicking assays. All MRPs at higher concentrations (0.2 mg/mL) d ecreased lipid peroxidation in linoleic acid emulsions. Relative effectiven ess of different MRPs to scavenge free radicals can vary with reaction cond itions and substrates.