Production of bioactive peptides with antioxidantand antihypertensive activities from wheat gluten using Withaniacoagulans

This study aimed to produce bioactive hydrolysates and peptide fractions from wheat gluten using Withania coagulans plantprotease, and evaluate antioxidant and angiotensin-converting-enzyme inhibitory activities. Plant samples were collectedand protease was extracted and purified using precipitation with ammonium sulfate. The enzyme activity was measured (۷.۳U/ml) and highest enzyme activity (۸۲%) was observed at ۴۵ °C and pH ۵. Wheat gluten hydrolysis was performed for ۶ hand the degree of hydrolysis was measured (۶.۵۱%). Fractionation of gluten hydrolysates was performed using ultrafiltrationand four peptide fractions were obtained, F۱ (MW < ۳ kDa), F۲ (۳ < MW < ۳۰ kDa) and F۳ (۳۰ < MW < ۱۰۰ kDa) and F۴(MW > ۱۰۰ kDa). The highest solubility at pH ۴ was exhibited by the F۴ fraction. The highest DPPH radical scavengingactivity was demonstrated by the F۱ fraction. The highest value for angiotensin-converting-enzyme inhibitory activity wasobtained for the F۲ fraction. Our results showed that wheat gluten hydrolysis with Withania coagulans protease was aneffective approach in order to generate bioactive hydrolysates and peptides, which could then be added to functional foodsformulations and pharmaceutical products.