title: Phenolic composition and inhibitory effect against oxidative DNA damage of cooked cowpeas as affected by simulated in vitro gastrointestinal digestion.
abstract: Cowpeas contain phenolic compounds with potential health benefits. The effect of simulated gastrointestinal digestion on phenolic composition of cooked cowpeas and the ability of the digests to inhibit radical-induced DNA damage was determined. A red and a cream-coloured cowpea type were used. The phenolic composition of acetone extracts and enzyme digests of cooked cowpeas was determined using UPLC-MS. Compounds such as p-hydroxybenzoic acid, p-coumaric acid, coumaroylaldaric acid and feruloylaldaric acid were present in the acetone extracts of the cooked cowpeas but were not detected in the enzyme digests. Glycosides of quercetin and myricetin decreased upon in vitro gastrointestinal digestion of cooked cowpeas whereas flavan-3-ols were hardly present except catechin glucoside. The enzyme digest of the red cowpea type was about thrice as effective as that of the cream cowpea type in protecting DNA from oxidative damage. The observation that enzyme digests of cooked cowpeas inhibited radical-induced DNA damage suggests that cowpea phenolics retain some radical scavenging activity after gastrointestinal digestion.
authors.affiliation: Department of Food Science, Institute of Food, Nutrition and Well-being, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa.
authors.forename: Alice M
authors.initials: AM
authors.lastname: Nderitu
authors.forename: Linda
authors.initials: L
authors.lastname: Dykes
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Awika
authors.forename: Amanda
authors.initials: A
authors.lastname: Minnaar
authors.forename: Kwaku G
authors.initials: KG
authors.lastname: Duodu
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003296:Cooking; D004249:DNA Damage; D004063:Digestion; D007887:Fabaceae / Q000737:chemistry / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000378:metabolism*; D006801:Humans; D013058:Mass Spectrometry; D008954:Models, Biological; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry* / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry* / Q000378:metabolism
chemical_list: D016166:Free Radical Scavengers; D010636:Phenols; D010936:Plant Extracts
keywords: Cowpeas; DNA damage; In vitro gastrointestinal digestion; Phenolic compounds