title: Effect of flavonols on wine astringency and their interaction with human saliva.
abstract: The addition of external phenolic compounds to wines in order to improve their sensory quality is an established winemaking practice. This study was aimed at evaluating the effect of the addition of quercetin 3-O-glucoside on the astringency and bitterness of wines. Sensory results showed that the addition of this flavonol to wines results in an increase in astringency and bitterness. Additionally, flavonol-human salivary protein interactions were studied using fluorescence spectroscopy, dynamic light scattering and molecular dynamic simulations (MD). The apparent Stern-Volmer (KsvApp) and the apparent bimolecular quenching constants (kqApp) were calculated from fluorescence spectra. The KsvApp was 12620±390M(-1), and the apparent biomolecular constant was 3.94×10(12)M(-1)s(-1), which suggests that a complex was formed between the human salivary proteins and quercetin 3-O-glucoside. MD simulations showed that the quercetin 3-O-glucoside molecules have the ability to bind to the IB937 model peptide.
authors.affiliation: Parc Tecnològic del Vi - VITEC, Ctra Porrera, 43730 Falset, Spain; Grupo de Investigación en Polifenoles, Facultad de Farmacia, University of Salamanca, Campus Miguel de Unamuno, E 37007 Salamanca, Spain.
authors.forename: Raúl
authors.initials: R
authors.lastname: Ferrer-Gallego
authors.affiliation: REQUIMTE-UCIBIO, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal.
authors.forename: Natércia F
authors.initials: NF
authors.lastname: Brás
authors.affiliation: Grupo de Investigación en Polifenoles, Facultad de Farmacia, University of Salamanca, Campus Miguel de Unamuno, E 37007 Salamanca, Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: García-Estévez
authors.affiliation: REQUIMTE-LAQV, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal.
authors.forename: Nuno
authors.initials: N
authors.lastname: Mateus
authors.affiliation: Grupo de Investigación en Polifenoles, Facultad de Farmacia, University of Salamanca, Campus Miguel de Unamuno, E 37007 Salamanca, Spain.
authors.forename: Julián C
authors.initials: JC
authors.lastname: Rivas-Gonzalo
authors.affiliation: REQUIMTE-LAQV, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal.
authors.forename: Victor
authors.initials: V
authors.lastname: de Freitas
authors.affiliation: Grupo de Investigación en Polifenoles, Facultad de Farmacia, University of Salamanca, Campus Miguel de Unamuno, E 37007 Salamanca, Spain. Electronic address: escriban@usal.es.
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Escribano-Bailón
mesh_terms: D001252:Astringents / Q000032:analysis* / Q000737:chemistry; D005419:Flavonoids / Q000032:analysis / Q000737:chemistry; D044948:Flavonols / Q000032:analysis* / Q000737:chemistry; D005960:Glucosides; D006801:Humans; D056004:Molecular Dynamics Simulation; D011794:Quercetin / Q000031:analogs & derivatives; D012463:Saliva / Q000737:chemistry*; D012471:Salivary Proteins and Peptides / Q000737:chemistry*; D013649:Taste; D014920:Wine / Q000032:analysis*
chemical_list: D001252:Astringents; D005419:Flavonoids; D044948:Flavonols; D005960:Glucosides; D012471:Salivary Proteins and Peptides; C532085:quercetin 3'-O-glucoside; D011794:Quercetin
keywords: Astringency; Flavonol; Fluorescence quenching; Human saliva; Molecular dynamic simulations; Wine