Antioxidant Activity of Peptides Extracted from Brewers’ Spent Grain Peptides

Abstract

Brewer’s spent grain (BSG) protein extracted from BSG was hydrolyzed using Alcalase to produce BSG protein hydrolysate. BSG protein hydrolysate was fractionated by ultrafiltration to obtain brown color BSG peptides. Antioxidant activity of BSG peptides was analyzeded and compared with reduced glutathione (GSH). BSG peptides exhibited 50% of scavenging activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical, and superoxide radical with concentrations less than 0.8 mg/mL, 0.6 mg/mL and 0.6 mg/mL, respectively. The reducing power of BSG peptides was 0.70 at the concentration of 2.00 mg/mL. 86.30% of the total amount of the BSG peptides purified by gel permeation chromatography was below 2000 Da. Because of its antioxidant activity, stability, nutritive value and low cost, BSG peptides exerts a possibility to use in food or cosmetic products.