Ion Exchange Separation of the Antitumor Component(s) of Yogurt Dialyzate

The active antitumor component of yogurt obtained by dialysis was further fractionated by ion exchange chromatography into acidic, basic, and neutral fractions, which were analyzed for activity by in vitro agar diffusion, cell culture, and in vivo mouse assay. Neither dialysate nor fractions showed any antitumor activity when tested by agar diffusion or cell culture techniques. When tested by in vivo mouse assay, the dialyzate as well as the anionic fraction showed significant inhibitory activity. The cationic fraction showed no activity. There was no direct relationship between stage of purification and antitumor activity. Moreover, the response of the dialyzate or anionic fraction was not linear with concentration. The antitumor activity of the yogurt fraction(s) may be related to a host-mediated immunological reaction or "activation" of the "inactive" component(s).