Exploration of the antioxidant and angiotensin-converting enzyme inhibitory potentials of oat bran peptides derived from in vitro digestion system

Abstract

The current study investigated the antioxidant and angiotensin-converting enzyme (ACE) inhibitory activity of wheat bran, oat bran, and wholegrain barley protein digesta and identified novel peptides. The small intestinal digesta of three cereal proteins contained significant levels of antioxidant and ACE inhibitory activity with the highest potentials in oat bran digesta. Therefore, oat bran intestinal digesta <3 kDa were analysed by tandem mass spectrometry. All the peptides that were identified originated from oat globulins. The current study recommends a novel peptide: LIVPQ related to other oat peptides expressing antioxidant and ACE inhibitory potential. Overall, the current study has shown that the storage proteins from three cereal proteins produce highly bioactive peptides at the end of the digestive system. The peptides identified in oat bran intestinal digesta with strong antioxidant and ACE inhibitory agents would also offer further applications towards improving human health