title: Contribution of individual phenolics to antioxidant activity and in vitro digestibility of wild rices (Zizania aquatica L.).
abstract: Zizania aquatica L. was analysed for total flavonoids, phenolics and HPLC profile in both free and bound phenolic fractions. The highest content of flavonoids (378-455mgRE/kg) was detected in bound fractions, while the highest polyphenols content (1061-2988mgGAE/kg) was determined in free fractions. Additionally, predominant phenolics were identified. To understand the contribution of individual phenolics to an antioxidant activity their mutual correlations were evaluated. Regarding free flavonoids, the main contributors to an antioxidant activity (r>0.7111) were epigallocatechin, epicatechin and rutin; while epicatechin, quercetin and rutin were the main contributors in bound fractions (r>0.6868). Concerning free phenolic acids, the main contributors to an antioxidant activity (r>0.7585) were ferulic, vanillic, ellagic, sinapic and syringic acids; while caffeic, sinapic, syringic, o-coumaric, p-hydroxy benzoic, vanillic, protocatechuic, gallic and cinnamic acids were the main contributors in bound fractions of wild rice (r>0.6538). Finally, in vitro organic matter and dry matter digestibility were assessed.
authors.affiliation: Tomas Bata University in Zlín, Department of Food Analysis and Chemistry, Náměstí T.G. Masaryka 5555, 760 01 Zlín, Czech Republic. Electronic address: sumczynski@ft.utb.cz.
authors.forename: Daniela
authors.initials: D
authors.lastname: Sumczynski
authors.affiliation: Tomas Bata University in Zlín, Department of Food Analysis and Chemistry, Náměstí T.G. Masaryka 5555, 760 01 Zlín, Czech Republic.
authors.forename: Eva
authors.initials: E
authors.lastname: Kotásková
authors.affiliation: Tomas Bata University in Zlín, Language Centre, Nám.TGM 1279, 760 01 Zlín, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Orsavová
authors.affiliation: Tomas Bata University in Zlín, Department of Food Analysis and Chemistry, Náměstí T.G. Masaryka 5555, 760 01 Zlín, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Valášek
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification* / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005419:Flavonoids / Q000302:isolation & purification / Q000378:metabolism; D012275:Oryza / Q000378:metabolism*; D010636:Phenols / Q000302:isolation & purification* / Q000378:metabolism*; D010936:Plant Extracts / Q000302:isolation & purification / Q000378:metabolism; D059808:Polyphenols
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols
keywords: Antioxidant activity; Flavonoids; Free and bound phenolics; Gluten-free cereals; HPLC-DAD; Zizania aquatica