IMPACT OF DIGESTION ON THE ANTIMUTAGENIC ACTIVITY OF THE MILK PROTEINCASEIN

The effect of caseinate and soy protein on the mutagenicity induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was assessed in in-vitro and in-vivo studies using a host-mediated assay. Of the two dietary pr oteins tested, only casein showed antimutagenic activity. Moreover, ev idence is presented that enzymatic digestion of sodium-caseinate great ly improved its antimutagenic potential. It is suggested that the mole cular structure of a protein determines its protective effect against mutagens. A stronger protection appears to correspond with a lack of s econdary and tertiary structure. These findings shed new Light on the possible prevention of mutagenesis and/or carcinogenesis by food prote ins, with an unique role for milk proteins. (C) 1997 Elsevier Science Inc.