Mechanism of blueberry anthocyanins inhibit glycation of bovine serum albumin-fructose/methylglyoxal revealed by LC ETD MS/MS

In order to investigate the inhibitory mechanism of blueberry anthocyanins (BAs) on glycation, bovine serum albumin-fructose (BSA-Fru) and BSA-methylglyoxal (BSA-MGO) models induced by ultrasound-microwave were implemented. BAs exhibited concentration-dependent inhibition of glycation, reducing advanced glycation end products (AGEs) formation by approximately 60% in the BSA-Fru model and 32.58% in the BSA-MGO model at 1.0 mg/mL. Notably, BAs significantly increased the molecular weight of glycated BSA and maintain BSA secondary structure by mitigating the decrease in α-helix content. LC-ETD-MS/MS analysis revealed that BAs reduced glycation sites from 23 to 18 in BSA-Fru and from 11 to 6 in BSA-MGO, with key sites including K75 and K88 being protected. Additionally, BAs increased the molecular weight of glycated BSA and mitigated the decrease in α-helix content. These findings suggest that BAs is potential effective glycation inhibitors and could be used in food processing to inhibit the formation of AGEs.