title: Peroxidase-like catalytic activity of Mn(3+)-octabromo-tetrakis(4-sulfophenyl)porphine on linoleate hydroperoxide and its analytical application.
abstract: To reveal an enzyme-like catalytic activity of metal-octabromo-tetrakis(sulfophenyl)porphines (M-OBPSs), their peroxidease-like catalytic activity on linoleate hydroperoxide (LOOH) were evaluated on the basis of dye-formation in the coloring reaction between N,N-diethylaniline and 4-aminoantipyrine that yields a quinoid-type dye. Among M-OBPSs tested, Mn(3+)-OBPS allowed to produce the largest amount of dye. The optimal conditions of the coloring reaction catalyzed by Mn(3+)-OBPS for the determination of LOOH were determined. A good linear calibration curve was obtained in the concentration range of 0.025-0.4mumole LOOH with good reproducibility (coefficient of variance=1.23%), suggesting that Mn(3+)-OBPS is a good artificial mimesis of the peroxidase for LOOH. In addition, Mn(3+)-OBPS was highly specific for LOOH even in the presence of cumene hydroxyperoxide or hydrogen peroxide. It was revealed that the peroxidase-like activity of Mn(3+)-OBTP is attributable to the redox cycle of Mn(3+)<-->Mn(4+).
authors.affiliation: Department of Pharmaceutical Sciences, Graduate School of Medicine and Dentistry and Pharmaceutical Sciences, Okayama University, Tsushima-Naka, Okayama 700-8530, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Mifune
authors.forename: Hidenori
authors.initials: H
authors.lastname: Kamiguchi
authors.forename: Taka-Aki
authors.initials: TA
authors.lastname: Tai
authors.forename: Seigo
authors.initials: S
authors.lastname: Kuremoto
authors.forename: Makiko
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Ikuko
authors.initials: I
authors.lastname: Tsukamoto
authors.forename: Madoka
authors.initials: M
authors.lastname: Saito
authors.forename: Youji
authors.initials: Y
authors.lastname: Kitamura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Saito