title: Generation and identification of angiotensin converting enzyme (ACE) inhibitory peptides from a brewers' spent grain protein isolate.
abstract: An alkaline extracted brewers' spent grain protein-enriched isolate (BSG-PI) was hydrolysed using Alcalase, Corolase PP, Flavourzyme and Promod 144MG, yielding Alc hydrolysate (H), CorH, FlavH and ProH, respectively. The degree of hydrolysis (DH) of the protein hydrolysates varied from 4.45% for ProH to 16.4% for CorH. The in vitro ACE inhibitory activity of the BSG-PI increased significantly following 15min incubations with Alcalase, Corolase PP and Flavourzyme. The 5kDa ultrafiltration permeates of FlavH and CorH resulted in lower ACE IC50 values than their respective hydrolysates. The bioactivity of the BSG-PI hydrolysates was retained after simulated gastrointestinal digestion (SGID) while SGID also resulted in the release of ACE inhibitory peptides from the BSG-PI and ProH. UPLC-MS/MS analysis resulted in the identification of 34 peptides. Of 12 synthesised peptides, IVY and ILDL were the most potent, having ACE IC50 values at 80.4±11.9 and 96.4±8.36μM, respectively.
authors.affiliation: Department of Life Sciences, University of Limerick, Castletroy, Limerick, Ireland.
authors.forename: Alan
authors.initials: A
authors.lastname: Connolly
authors.affiliation: Department of Life Sciences, University of Limerick, Castletroy, Limerick, Ireland.
authors.forename: Martina B
authors.initials: MB
authors.lastname: O'Keeffe
authors.affiliation: Department of Life Sciences, University of Limerick, Castletroy, Limerick, Ireland.
authors.forename: Charles O
authors.initials: CO
authors.lastname: Piggott
authors.affiliation: Department of Life Sciences, University of Limerick, Castletroy, Limerick, Ireland; Food for Health Ireland, Department of Life Sciences, University of Limerick, Castletroy, Limerick, Ireland.
authors.forename: Alice B
authors.initials: AB
authors.lastname: Nongonierma
authors.affiliation: Department of Life Sciences, University of Limerick, Castletroy, Limerick, Ireland. Electronic address: dick.fitzgerald@ul.ie.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: FitzGerald
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D002853:Chromatography, Liquid / Q000379:methods*; D002523:Edible Grain / Q000737:chemistry* / Q000378:metabolism; D006868:Hydrolysis; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology; D010940:Plant Proteins / Q000737:chemistry* / Q000378:metabolism; D011492:Protein Hydrolysates / Q000737:chemistry* / Q000494:pharmacology*; D013381:Subtilisins / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D010455:Peptides; D010940:Plant Proteins; D011492:Protein Hydrolysates; D013381:Subtilisins
keywords: ACE inhibition; BSG protein; Barley; Bioactive peptides; Fractionation; Simulated gastrointestinal digestion