Effects of Spinosin on nonenzymatic glycation of β-lactoglobulin: A mechanism study based on multi-spectroscopy analysis and molecular docking

Spinosin is an excellent antiglycation agent. • The cross-linked structure and β-amyloid proteins were formed during glycosylation. • The glycation sites protected by Spinosin were determined by molecular docking analysis. • Spinosin quenched the fluorescence of β-lactoglobulin via a static quenching mechanism. Inhibiting advanced glycation end products (AGEs) in thermally processed foods is crucial for managing diabetic complications. This study evaluated the antiglycation activity and mechanisms of Spinosin (SP) from sour jujube seeds in three glycation systems, namely, β-lactoglobulin (β-Lg) with glucose, glyoxal, or glycolaldehyde, incubated at 37 °C in the dark. The results showed that 40–160 μM SP significantly inhibited AGEs formation, with inhibition rates at 160 μM reaching 98.83 ± 0.1%, 83.46 ± 2.1%, and 37.26 ± 0.1% for the glucose, glyoxal, and glycolaldehyde systems, respectively. In addition, SP also inhibited protein oxidation, cross-linking, and the formation of amyloid cross-β structures, potentially contributing to the preservation of β-Lg structure. Molecular docking suggested that SP may shield glycation-prone residues via steric hindrance. Fluorescence titration indicated hydrogen-bonding and van der Waals interactions with a temperature-decreased binding constant (exothermic). These findings suggest that SP is a multi-pathway natural antiglycation agent, but its efficacy in real food matrices requires further validation. Download: Download high-res image (190KB) Download: Download full-size image