Complex formation between oxidized lipids and egg albumin

The nature of the reactions leading to the formation of complexes between oxidized lipids and proteins is little understood. Complexes were formed between thermally oxidized and thermally polymerized corn oils and egg albumin. The results indicated that the thermally oxidized oil was much more reactive than the thermally polymerized oil. The nature and extent of oxidative groups in the lipid were varied and reacted with egg albumin. The keto and epoxy groups seemed to have a pronounced influence on complex formation while the hydroxy and hydroperoxide groups were observed to be less reactive. Acetylation of egg albumin did not significantly decrease its complexing ability with thermally oxidized corn oil. Further confirmation that the reactive groups in the protein were not covalently tied up to the lipid was obtained by estimating these groups in the original protein and in the complexed protein. IR analyses of oxidized lipid‐alumina, oxidized lipid‐egg albumin and fatty acid‐urea complexes indicated that the characteristic absorption was due to bonded O‐H stretching vibration in the first two complexes and the bonded N‐H stretching vibration in the two latter complexes.