title: Release of flavonoids from lupin globulin proteins during digestion in a model system.
abstract: Lupin seed globulin proteins form complexes with flavonoids, predominantly apigenin C-glycosides. Enzymes typical for the gastrointestinal tract were used to hydrolyze lupin seed globulins. Release of native flavonoids as a result of the proteolysis reaction was observed. Different analytical methods such as size exclusion chromatography, HPLC-MS, and fluorescence spectroscopy (steady-state fluorescence, fluorescence anisotropy, fluorescence lifetimes) were used for a detailed characterization of this phenomenon. Flavonoids liberated from lupin globulin proteins as a result of pancreatin-catalyzed digestion were bound by γ-conglutin resistant to this enzyme. Two possible mechanisms of this interaction may be suggested: hydrogen bonding between oligosaccharide chains of glycoproteins and the sugar moieties of the flavonoid glycosides or electrostatic attraction between positively charged γ-conglutin and flavonoids partially ionized at pH 7.5.
authors.affiliation: Department of Food Biochemistry and Analysis, Poznan University of Life Sciences, Poznan, Poland. jarczu@up.poznan.pl
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Czubinski
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Dwiecki
authors.forename: Aleksander
authors.initials: A
authors.lastname: Siger
authors.forename: Piotr
authors.initials: P
authors.lastname: Kachlicki
authors.forename: Grazyna
authors.initials: G
authors.lastname: Neunert
authors.forename: Eleonora
authors.initials: E
authors.lastname: Lampart-Szczapa
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Nogala-Kalucka
mesh_terms: D047310:Apigenin / Q000378:metabolism; D004063:Digestion; D005419:Flavonoids / Q000378:metabolism*; D005916:Globulins / Q000378:metabolism*; D031297:Lupinus / Q000737:chemistry*; D008954:Models, Biological; D010194:Pancreatin / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D059748:Proteolysis; D012639:Seeds / Q000737:chemistry*
chemical_list: D005419:Flavonoids; D005916:Globulins; D010940:Plant Proteins; D047310:Apigenin; D010194:Pancreatin