Impact of a Water-Soluble Gallic Acid-Based Dendrimer on the Color-Stabilizing Mechanisms of Anthocyanins

• Tipo: Artigo em Revista Científica Internacional
• Data: 2019

Autores

Luis Cruz (Autor) FCUP; Baslio, N (Autor) Outra; Mendoza, J (Autor) Outra; Nuno Mateus (Autor) FCUP; Victor de Freitas (Autor) FCUP; Tawara, MH (Autor) Outra; Correa, J (Autor) Outra; Fernandez Megia, E (Autor) Outra

Revista

Título: Chemistry - A European Journal

Vol. 25

ISSN: 0947-6539

Editora: Wiley-Blackwell

Indexação

ISI Web of Knowledge - 17 Citações

Scopus - 17 Citações

Outras Informações

ID Authenticus: P-00Q-Z5V

DOI: 10.1002/chem.201901912

Abstract (EN): The interaction of two anthocyanins with a water-soluble polyanionic dendrimer was studied through UV/Vis, stopped-flow, and NMR spectroscopy. Cyanidin-3-glucoside (cy3glc) revealed a stronger interaction than malvidin-3-glucoside (mv3glc) at pH 1 according to their apparent association constants. A higher color increased was also obtained for cy3glc at pH 3.5 as a result of this stronger interaction. A high-frequency chemical shift of the cy3glc aromatic protons suggest the formation of ionic pairs. The interaction parameters (K approximate to 700 m(-1), n approximate to 295) indicated the binding of approximately two anthocyanin molecules by each sulfate group. The equilibrium and rate constants of cy3glc in the presence of dendrimer showed an increased stability of the flavylium cation and a higher protection of this species from hydration (pK '(a) and pK(h) increased almost one pH unit). The tuning and color stabilization of anthocyanins by using this dendrimer allow novel applications as colorimetric sensors for food packaging.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 11