Polyphenols and red wine as peroxynitrite scavengers: a chemiluminescent assay

ALVAREZ S; ZAOBORNYJ T; ACTIS-GORETTA L; FRAGA C; BOVERIS A

Ann N Y Acad Sci

Año: 2002 vol. 957 p. 271 - 273

A novel chemiluminescent assay for evaluating peroxynitrite (ONOO-)-scavenging capacity was developed. The experimental protocol ensures sensitivity and reproducibility of measurements. The addition of 0-500f1oMONOO- to rat liver homogenate generated a luminous signal that was analyzed by chemlluminescence in a LKB Wallac liquid scintillation counter. The obtained optimal conditions were: 1-2mglmL of homogenate protein in 120mM KCI,30mM phosphate buffer (pH 7.4), and 220f10MONOO' at 30°C.As polyphenols we used (+)-catechin, ( - )-epicatechin, and myricetin. The most efficient of the compounds tested was myricetin with an ICso of 20f1oM. The effectiveness of this method was verifled by evaluating the antioxidant ability of three red wine samples to decrease peroxynitrite-initiated chemiluminescence. The ONOO- -scavenging activity of wines measured by this assay was related to the phenolic level of the samples. The quickness and reliability of this assay makes it particularly suitable for a large-scale screening of watery food extracts.