Grunwald and Richards, 2007 – Ability of Hemin-binding Antibodies From Egg to Inhibit Lipid Oxidation in Muscle Foods

Lipid oxidation causes quality deterioration in muscle foods. The hen has been used previously as a bio-reactor to produce antibodies for various purposes. Our goal was to inject hemin bound to bovine gamma globin into laying hens so that antibodies specific for hemin would be deposited in the egg yolks. Those antibodies could then be harvested from the yolk and tested for their ability to inhibit hemin-mediated lipid oxidation in washed muscle tissue. A tight binding of hemin by the specific antibody has the potential to inactivate hemin as a catalyst of lipid oxidation. A previous report also showed that the hen can be used to produce antibodies specific for gamma-human hemoglobin. Therefore we also examined producing antibodies in the hen that could potentially inhibit fish hemoglobin-mediated lipid oxidation. Antibodies endogenous to egg yolk from hens that received no antigen injection accelerated hemin-mediated lipid oxidation in washed muscle. This may be due to the ability of the native antibody proteins to weakly bind and subsequently deliver hemin into lipid phases of the washed muscle. After injecting hens with hemin-based antigens, it appeared that only a small fraction of the total antibodies obtained were specific for hemin. Also, the amount of hemin binding proteins was not elevated in antibodies from the hens injected with hemin-based antigens compared to control antigens lacking hemin. This may explain the inability of antibodies from hens receiving hemin-based antigens to decrease rates of heminmediated lipid oxidation in washed muscle. Alternatively, the hemin specific antibodies may also only weakly bind hemin and thus have a pro-oxidant effect. When trout hemoglobin was used as the antigen, again a small fraction of the total antibodies obtained appeared to be specific for trout hemoglobin which can explain the inability of antibodies from hens injected with hemoglobin to affect rates of trout hemoglobin-mediated lipid oxidation in washed muscle. Future work could be to fractionate the total antibodies from egg yolks of hens injected with the antigens containing hemin (or hemoglobin) to determine if the desired antibodies can be obtained in sufficient purity and yield to inhibit hemin or hemoglobin-mediated lipid oxidation. However, this would likely not be cost-effective industrially. Since the antibody preparations from egg yolk were not capable of inhibiting hemin or hemoglobin-mediated lipid oxidation, we investigated the presence of hemin-binding proteins in the underutilized egg shell. The major hemin-binding protein from egg shell was extracted, purified, sequenced, and identified as ovocleidin-116.