Structure, antioxidant activity, and neuroprotective effect of black soybean ( Glycine max (L.) merr.) protein hydrolysates

The potential biological properties of protein hydrolysates have generated considerable research interest. This study was to hydrolyze black soybean protein (BSP) using five different commercial enzymes, and elucidate the influence of these enzymes on the structure and biological activities of the resulting hydrolysates. Enzymatic treatment changed secondary and tertiary structures of BSP, decreased particle size, alpha-helix and beta-sheet. Alcalase hydrolysate had the highest hydrolytic degree (29.84 %), absolute zeta potential (38.43 mV), the smallest particle (149.87 nm) and molecular weight (<3 kDa). In silico revealed alcalase hydrolysate had the strongest antioxidant potential. This finding was further validated through the lowest IC50 (mg/mL) in DPPH (2.67), ABTS (0.82), Fe2+ chelating (1.33) and & sdot;OH (1.12). Moreover, cellular antioxidant assays showed alcalase hydrolysate had the strongest cytoprotective effects on H2O2-induced PC12 cells. These results suggest BSPEHs, especially those prepared by alcalase, have potential as bioactive ingredients for nutrition, healthcare and food industry.