Article

A reaction between the superoxide free radical and lipid hydroperoxide in sodium linoleate micelles.

School of Biological Sciences, Macquarie University, North Ryde, New South Wales 2113, Australia
Archives of Biochemistry and Biophysics (impact factor: 2.93). 04/1982; 214(1):1-11. DOI:10.1016/0003-9861(82)90001-7 pp.1-11
Source: PubMed

ABSTRACT The oxidation of unsaturated fatty acid micelles by the superoxide free radical (), during γ irradiation in the presence of formate, is kinetically distinct from oxidation by hydroxyl free radicals (HO.). The evidence suggests that a direct reaction between () and lipid hydroperoxide initiates a chain oxidation process in the micelles. While tetranitromethane, which reacts rapidly with (), protects the micelles from oxidation, active superoxide dismutase is no more effective than its apoprotein, due to lack of penetration of the micellar environment. We discuss these findings in the light of recent literature, and with reference to their possible significance for biological systems.

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