Kinetics of phycocyanine bilin groups destruction by peroxyl radicals

Lissi, EA; Pizarro M.; Aspée A.; Romay, C

Abstract

Bilin groups in c-phycocyanine are readily bleached by peroxyl radicals produced in the thermolysis of 2,2'-azobis(2-amidinopropane). From an evaluation of the bilin groups destroyed per radical that interacts with the protein, it is concluded that the bilin moiety is the main target of the radicals. Kinetic expressions are derived that allows an estimation of the substrate reactivity from the analysis of the rate of bilin group modification as a function of the protein concentration. From this analysis it is concluded that micromolar concentrations of c-phycocyanine are able to reduce the steady state concentration of the peroxyl radicals by one half, indicating a high antioxidant activity for this compound. This conclusion is confirmed by measuring the capacity of the protein to protect 1-naphthol from modification by peroxyl radicals. The results obtained show that the bilin groups have, on a molar basis, an antioxidant activity similar to that of potent antioxidants such as catechin. (C) 2000 Elsevier Science Inc.

Más información

Título según WOS: Kinetics of phycocyanine bilin groups destruction by peroxyl radicals
Título según SCOPUS: Kinetics of phycocyanine bilin groups destruction by peroxyl radicals
Título de la Revista: FREE RADICAL BIOLOGY AND MEDICINE
Volumen: 28
Número: 7
Editorial: Elsevier Science Inc.
Fecha de publicación: 2000
Página de inicio: 1051
Página final: 1055
Idioma: English
DOI:

10.1016/S0891-5849(00)00193-3

Notas: ISI, SCOPUS