negatively regulates plasma lipoprotein particle oxidation regulation of plasma lipoprotein oxidation negative regulation of plasma lipoprotein oxidation GO:0034445 negative regulation of plasma lipoprotein particle oxidation Any process that stops, prevents, or reduces the frequency, rate or extent of lipoprotein particle oxidation, occurring in the blood plasma. inhibition of plasma lipoprotein oxidation biological_process negative regulation of cellular component organization negative regulation of multicellular organismal process biological regulation