Comparison of the antioxidative and cytotoxic properties of glucose-lysineand fructose-lysine Maillard reaction products

The antioxidative activity and cytotoxic effect of different fractions gene rated from whole mixtures of model Maillard reaction products (MRPs) made f rom glucose-lysine (Glc-Lys) and fructose-lysine (Fru-Lys) reactants were t ested. MRPs were derived from Glc-Lys and Fru-Lys by autoclave heating, and ethanol fractionation. All MRP fractions showed various degrees of antioxi dative activity when evaluated by a deoxyribose oxidative degradation assay . A significant difference (P < 0.05) was seen in the affinity to inhibit F enton-reaction-induced free radical production, for both Glc-Lys and Fru-Ly s ethanol precipitates, and also the Fru-Lys ethanol extract. Similar prote ctive antioxidative activity of the different MRP fractions was not exhibit ed in a DNA nicking assay. Cytotoxicity potential of the MRPs was investiga ted using Caco-2 cells. The greater cytotoxicity observed for both Glc-Lys and Fru-Lys ethanol precipitates was specific to the higher molecular weigh t fractions. Cytotoxicity also depended on incubation time, MRP concentrati on, and sugar source. (C) 2000 Elsevier Science Ltd. All rights reserved.