Characterization of Aqueous Components in Chicken Breast Muscle as Inhibitors of Hemoglobin-Mediated Lipid Oxidation
Journal article, 2005
Unheated press juice (PJ) obtained from chicken breast muscle was a potent inhibitor of hemoglobin-mediated lipid oxidation in washed cod muscle. The <1 kDa fraction had a negligible effect on the rate of lipid oxidation. The high-molecular-weight (HMW) fraction was mildly inhibitory when added alone and highly inhibitory in the presence of <1 kDa components. Proteins of the HMW fraction were further fractionated by ammonium sulfate precipitation. Proteins in the 80% fraction were most inhibitory compared with other precipitated fractions on an equal protein basis. Inhibition by PJ was substantially decreased due to treatment with ascorbate oxidase. Adding ascorbate to the HMW fraction did not increase its inhibition, which suggested the presence of a complex ascorbate-reducing system in PJ consisting of HMW and low-molecular-weight (LMW) components. The ability of added ceruloplasmin to inhibit lipid oxidation was remarkably enhanced by addition of ascorbate or the <1 kDa fraction. Heated and centrifuged PJ had 8 times more LMW iron compared to unheated PJ. Adding heated PJ to washed cod containing hemoglobin slightly increased the rate and extent of lipid oxidation.