title: Evidence for copigmentation interactions between deoxyanthocyanidin derivatives (oaklins) and common copigments in wine model solutions.
abstract: The aim of this study was to investigate interactions possibly taking place in red wine between oaklins, which are deoxyanthocyanidin derivatives (guaiacylcatechin-pyrylium and syringylcatechin-pyrylium), and several copigments: catechin (CP1), epicatechin (CP2), chlorogenic acid (CP3), epigallocatechin (CP4), and procyanidin B3 (CP5). The results show that oaklins, like common anthocyanins, also present copigmentation interactions that further stabilize the flavylium cation in hydroalcoholic solutions. Molecular dynamics simulations were also performed to interpret the binding data, to specify the relative arrangement of the pigment and copigment molecules within the complexes, and to interpret their absorption properties in the visible range.
authors.affiliation: Departamento de Quı́mica, Faculdade de Ciências, Universidade do Porto , Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
authors.forename: André
authors.initials: A
authors.lastname: Sousa
authors.forename: Paula
authors.initials: P
authors.lastname: Araújo
authors.forename: Luís
authors.initials: L
authors.lastname: Cruz
authors.forename: Natércia F
authors.initials: NF
authors.lastname: Brás
authors.forename: Nuno
authors.initials: N
authors.lastname: Mateus
authors.forename: Victor
authors.initials: V
authors.lastname: De Freitas
mesh_terms: D000872:Anthocyanins / Q000737:chemistry*; D008956:Models, Chemical; D056004:Molecular Dynamics Simulation; D010860:Pigments, Biological / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D014920:Wine
chemical_list: D000872:Anthocyanins; D010860:Pigments, Biological