Abstract: High temperatures involved in food processing often cause non-enzymatic glycosylation leading to the production of hazardous substances. Therefore, this phenomenon should be avoided as much as possible during food processing. In this study, the antioxidant capacity of tea polyphenol (TP) modified with maleic anhydride (MA-TP) and its inhibitory effects on non-enzymatic glycosylation were determined by ultraviolet-visible (UV-Vis) spectrophotometry, high performance liquid chromatography (HPLC) and fluorescence spectroscopy. The results showed that MA-TP could effectively inhibit non-enzymatic glycosylation although having reduced ability to scavenge 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation (P < 0.05). In particular, the inhibitory effect of MA-TP on precursor formation and browning degree during non-enzymatic lysine-fructose glycosylation reaction was significantly enhanced compared with that of TP. In addition, the maximum inhibition rates of MA-TP on glyoxal, methylglyoxal and total fluorescent glycosylation end products were 82.95%, 40.33% and 70.25%, respectively, significantly higher than those of TP and the positive control aminoguanidine (AG) (P < 0.05). The maximum inhibition rate on 3-deoxyglucosone was 45.01%, and during the middle and late stages of the reaction, the inhibitory effect of MA-TP on 3-deoxyglucosone was significantly better than that of TP (P < 0.05). MA-TP also showed inhibitory effect on the production of pentosidine with maximum inhibition rate of 88.43%, similar to that of TP but significantly better than that of the positive control AG (P < 0.05). In conclusion, the findings from this study can provide a theoretical reference for the application of modified tea polyphenols as non-enzymatic glycosylation inhibitors in the field of foods.

Key words: maleic anhydride; tea polyphenols; modification; non-enzymatic glycosylation; inhibitory effects