The Degree of Methylation Influences the Degradation of Pectin in the Intestinal Tract of Rats and In Vitro

Abstract

We investigated the degradation, metabolism, fate, and selected effects of pectin in the intestinal tract of rats. Conventional and germfree rats were fed for 3 wk diets containing 6.5% pectin (degree of methylation 34.5, 70.8 and 92.6%, respectively) or pectin-free diets. Pectin passes the small intestine as a macromolecule. The molecular weight distribution of pectins isolated from intestinal contents of germfree rats were unaffected by diet. No or very little galacturonan was found in cecum, colon or feces of most of the conventional rats. In colon contents of some conventional rats, di- and trigalacturonic acid were present. Total anaerobic and Bacteroides counts were greater in groups fed pectin. The concentration of short-chain fatty acids (SCFA) was higher in cecum and feces in all pectin-fed groups. With increasing degree of methylation, the formation rate of SCFA decreased in the cecum of conventional rats. During in vitro fermentation of pectin with fecal flora from rats, unsaturated oligogalacturonic acids appeared as intermediate products. Low-methoxyl pectin was fermented faster than high-methoxyl pectins in vivo and in vitro. Pectin-fed rats had greater ileum, cecum and colon weights. We conclude that structural parameters of pectin influence its microbial degradation in the intestinal tract.

Effect of pectin feeding on obesity development and duodenal alkaline phosphatase activity in Sprague-Dawley rats fed with high-fat/high-energy diet

“…Decreased overall food intake in pectin-fed rats was accompanied with increased satiety and with increased circulating concentrations of the gut satiety hormones (1). In contrast, several studies have suggested that pectin does not influence food intake and growth rate (7,9).…”

By-products of Rice Processing: An Overview of Health Benefits and Applications

“…It has also been suggested that the production of butyrate from these fibres could protect against the initial stages of colon carcinogenesis [92]. Butyrate, as suggested, is able to arrest the growth of neoplastic colonocytes and inhibit the preneoplastic hyperproliferation induced by the several tumour initiators and promoters [93,94]. This type of fibre also has been suggested to be paramount to carcinogenesis by changing from propionate to butyrate, as observed in animals fed hydrolysed guar [95].…”

Fermentation Patterns of Various Pectin Sources by Human Fecal Microbiota

“…It is also used as ingredients in the prevention of coronary heart disease, colon cancer, hypercholesterolemia [11]- [14]. Physiological (fermentability by microbiota) and functional properties (gelation or biding of metal ions) of pectin are different, relying on its structural parameters like molecular weight, degree of methylation (DM), and distribution of free and methoxylated carboxyl groups within the galacturonan chains [15]. Few studies have been investigated the effects of purified pectin on fermentation pattern and gut microbiota.…”