摘要
About 39 million tons of Brewer’s spent grain(BSG),the main by-product of beer manufacturing,are produced annually and is used for low value applications.To valorise this rich bioresource,the present work entails bioprocessing of BSG with various proteases(Novozymes)at two different concentrations(4%and 9%)to solubilise protein,carbohydrate and polyphenols from the grain and evaluate its effect on gut and brain health.The results show the highest(p<0.05)FRAP(Ferric Reducing Antioxidant Power)based antioxidant activity was obtained for Pro 5(4%:108.10±4.17μmole Trolox Equivalence(TE)/g protein,18.06±0.70μmole TE/g d.w.,which was 3.6 times higher than untreated control extracts.The highest DPPH(1,1-diphenyl-2-picrylhydrazyl)scavenging activity was obtained for the same extract(Pro 5 at 4%:0.118±0.006μg AAE/mg d.w.,9%:0.110±0.006μg AAE/mg d.w).Proximate composition showed this extract to contain the highest concentration of proteins at 21.66%±2.71,and color analysis showed the same Pro 5(4%)extract to be the darkest(L*53.73)indicating the possible presence of dark polyphenols.Anticancer screening showed Control and Pro 1 to possess cytotoxic effect against colon cancer cells with IC_(50)of 3.2 and 13.91 mg/mL,respectively.No significant activity was noted against the brain cancer cell line.Thus anti-colon cancer activity of BSG extracts highlights its potential in gut health.The observed bioactivity resulted from a combination of peptides,carbohydrates and polyphenolic compounds in the extract and warrants further characterisation for targeted nutraceutical applications.
