INHIBITION OF PHOSPHATIDYLCHOLINE LIPOSOME OXIDATION BY PORCINE PLASMA

Porcine plasma inhibited iron-catalyzed lipid oxidation at the pH range (5.5-7.0) and temperatures (4-37-degrees-C) commonly found in food. Increasing concentrations of frozen-thawed plasma resulted in increased antioxidant activity until 100% inhibition was reached at 5.36 mg plasma protein/mL assay. In addition to iron, porcine plasma also inhibited hydrogen peroxide-activated hemoglobin- and photoactivated riboflavin-catalyzed lipid oxidation. The plasma partially lost antioxidant activity during refrigerator storage (4-degrees-C) after 8 days but not during frozen storage (-15-degrees-C) after 246 days. Dialyzing the plasma increased inhibition of iron-catalyzed lipid oxidation 1.8-fold higher than undialyzed plasma (1.5 mg plasma protein/mL).