The relationships between molecular structure and various food-physiological.functions of egg white ovomucin : analysis and application

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Egg white ovomucin (OVM) is a fibriform and highly viscous macromolecular glco-protein. It consists of α-and β-subunits. The molecular characteristics and food physiological function of OVM are not yet understood. A majar, goal of OVM research in this siudy is to determine its molecular structure and to analyze the function as a food-physiologically active substances.The primary amino acid sequences of both cDNA encoding their subunits. The 2087 amino acid residues in full lengh of α-subunit were represented, and noted to have higher homology, with human intestinal mucin, MUC2.On the other hand, the amino acid sequence of β-subunit were partially represented.The experiment was designed to evaluate the effect of casein or OVM on cholesterol metabolism in rats. Serum total cholesterol was significantly lower in rats fed OVM than in those fed casein. OVM may also inhibit the reabsorption of bile acids. in the ilpum thus lowering the serum cholesterol level.The antitumor activities of OVM, and its 7OkDa, 120kDa, and 220kDa fragments were examined under the cultured tumor cells and grafted tumor systems. OVM and its fragments exerted direct cytotoxicity on tumor cells with necrotxc changes and an indirect cytotoxic effect via the host's immune system. It was demonstrated that the angiogenesis(the formation of new capillary blood vessels) in the tumor tissues was inhibited.From these results, the relationships between the whole or partial characteristic molecular structure and food-physiological functions were discussed.