Abstract: Objective: To produce specific chicken egg yolk immunoglobulin against lipopolysaccharide(LPS), used for preventing and detecting E.coli O157:H7 in comparison with the immunity of LPS and O-specific polysaccharide (O-SP). Methods: Hens, 25-week old, were immunized with E.coli O157:H7, LPS, O-SP respectively after being emulsified with incomplete Freuds’ adjuvant. By a simple method of water dilute of protein IgY to separate the antibody from egg yolk, purified by ion-exchange chromatograph, the IgY detected by SDS-PAGE and indirect-ELISA, and its immunologic competence was determined by double immunodiffusion. Results and Conclusion:The IgY titers of E.coli O157:H7 are obtained with 600μg/ml LPS, 1200μg/ml LPS and 2000μg/ml LPS, as O-SP respectively 1:32000, 1:28000, 1:32000, 1:12000 and 1:40000. It is purified by ion exchanging with 0.185mol/L THS washing. The immunity of lipopolysaccharide and O-SP is strong. The IgY anti-OSP produced by immunizing hens shows high titer, high purification and well specificity by chicken egg yolk immunoglobulin. The results provide scientific basis for preventing and infection curing by O157:H7 and further ways exploring of detecting O157:H7 with specific anti-LPS IgY produced from hens.

Key words: E.coli O157:H7, preventing, endotoxin, egg yolk antibody, preparation