Abstract: The present study aimed to evaluate the antioxidant and antiglycation activities of quercetin methyglyoxal (MGO) adducts, including mono- (MM-1) and di-MGO (DM-2) adducts. The antioxidant abilities were assessed through ferric reducing assay and the measurement of oxidation induction time of lard. The inhibitory effect of MGO-quercetin adducts on the formation of MGO and glyoxal (GO) in oil system at high temperature was explored. Ovalbumin (OVA)-glucose system under simulated food processing conditions and bovine serum albumin (BSA)-glucose system under simulated physiological conditions were applied for the measurement of antiglycation activity by gas chromatography and fluorescence spectroscopy. The results indicated that both mono- and di-MGO quercetin adducts had antioxidant capacity and inhibitory activity on the formation of MGO/GO in the oil system. Meanwhile, MGO-quercetin adducts inhibited glycation under simulated Maillard reaction in food processing and physiological conditions in a concentration-dependent fashion, in the increasing order of DM-2 < MM-1 < quercetin. Therefore, MGO-quercetin adducts still played an important role in antioxidation and antiglycation during the process of protein glycosylation.

Key words: MGO-quercetin adduct, quercetin, methyglyoxal (MGO), glyoxal (GO), advanced glycation end products (AGEs)