ANTICARCINOGENIC ACTION OF APPLE PECTIN ON FECAL ENZYME-ACTIVITIES AND MUCOSAL OR PORTAL PROSTAGLANDIN E-2 LEVELS IN EXPERIMENTAL RAT COLONCARCINOGENESIS

Pectin is a partially methoxylated polymer of galacturonic acid obtain ed from fruits, Among pectin, apple pectin exerts stronger bacteriosta tical action on Staphylococcus aureus, Streptococcus faecalis, Pseudom onas aeruginosa ann Escherichia coli in comparison with citrus pectin. In this study, we used water-soluble methoxylated pectin from apple. The diet, supplemented by 20% apple pectin, significantly decreased th e number of tumors and the incidence of colon tumor. PGE(2) level in d istal colonic mucosa in 20% apple pectin fed rats were lower than thos e in basal diet fed rats. Fecal beta-glucuronidase activities in the a pple pectin fed group, which has been considered a key enzyme for the final activation of Dimethylhydrazine metabolism to carcinogens in the colonic lumen, were significantly lower than those in control group a t initiation stage of carcinogenesis. In the case the concentrations o f beta-glueosidase and azoreductase were also decreased. The effect of apple pectin on the colon carcinogenesis may partially depend on PGE( 2) concentration decrease in colonic mucosa and on the type of pectin, also related to fecal enzyme activities.