Interactions of ferric ions with olive oil phenolic compounds

• Tipo: Artigo em Revista Científica Internacional
• Data: 2005

Autores

Paiva Martins, F (Autor) FCUP; Gordon, MH (Autor) Outra

Revista

Título: Journal of Agricultural and Food Chemistry

Vol. 53

Páginas: 2704-2709

ISSN: 0021-8561

Editora: American Chemical Society

Indexação

ISI Web of Knowledge - 53 Citações

Scopus - 59 Citações

Classificação Científica

FOS: Ciências agrárias > Outras ciências agrárias

Outras Informações

ID Authenticus: P-000-3WA

DOI: 10.1021/jf0481094

Abstract (EN): The ferric complexing capacity of four phenolic compounds, occurring in olives and virgin olive oil, namely, oleuropein, hydroxytyrosol, 3,4-dihydroxyphenylethanol-elenolic acid (3,4-DHPEA-EA), and 3,4-dihydroxyphenylethanol-elenolic acid dialdehyde (3,4-DHPEA-EDA), and their stability in the presence of ferric ions were studied. At pH 3.5, all compounds formed a reversible 1:1 complex with ferric ions, but hydroxytyrosol could also form complexes containing > 1 ferric ion per phenol molecule. At pH 5.5, the complexes between ferric ions and 3,4-DHPEA-EA or 3,4-DHPEA-EDA were relatively stable, indicating that the antioxidant activity of 3,4-DHPEA-EA or 3,4-DHPEA-EDA at pH 5.5 is partly due to their metal-chelating activity. At pH 7.4, a complex containing > 1 ferric ion per phenol molecule was formed with hydroxytyrosol. Oleuropein, 3,4-DHPEA-EA, and 3,4-DHPEA-EDA also formed insoluble complexes at this pH. There was no evidence for chelation of Fe(II) by hydroxytyrosol or its derivatives. At all pH values tested, hydroxytyrosol was the most stable compound in the absence of Fe(III) but the most sensitive to the presence of Fe(III).

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6