Cecum bacteria

Only a few studies have been undertaken on the role of bacteria in nitrosation at neutral pH in the Intestinal tract itself. Hashimoto al. (9 ) demonstrated that by changing the equilibrium between different species of microorganisms in the gut, (by administration of antibiotics and inoculation with nitrate-reducing strains) dimethylnitrosamine (NDMA) accumulated in the stomach and cecum of rats fed dlmethylamine (DMA) and nitrate. The authors describe only one experimental group, however, and the mechanism of NDMA formation is not clear. 

These studies indicate 1) fermentable fiber increases the total number of viable anaerobic bacteria in the cecum, but not the stomach or small intestine of rats 2) the microfloral capacity for hydrolysis of glucuronide conjugates, for nitroreduction, and for azoreduction is elevated in fermentable fiber-fed rats 3) this increased capacity for microfloral metabolism of nitrobenzene and dinitrotoluene is correlated with an elevation in the toxicity of these nitroaromatics 4) the role fiber plays in the modulation of chemical toxicity is a function of the fiber-type and the structure of the toxicant. 

E. coli infections. If a prebiotic can be added to the daily feed and it subsequently stimulates the beneficial bacteria in the colon at the expense of pathogens, it is most probable that these bacteria, namely bifidobacteria and lactobacilli, adhere to sites on epithelial cells and ultimately prevent the binding of pathogenic bacteria [112]. In diets containing reasonable quantities of carbohydrates saccharolytic fermentation will prevail, thus the pH of the GIT will remain stable and subsequently reduce the onset of Clostridia infections, as a more alkaline pH is required by species of this genus. Inulin added to rabbit feed was fermented in the cecum, produced SCFA, and reduced the risk of clostridiosis [113]. 

The proximal small intestine (duodenum and jejunum) normally contains few bacteria. Most ingested bacteria do not survive the acidic environment of the stomach and therefore few live organisms normally enter the small bowel. The motfiity of the jejunum prevents fecal-type organisms from progressing up into the jejunum from the cecum. The ileum normally contains some fecal-type bacteria. Colonization of the upper small bowel is described as bacterial overgrowth and usually occurs as a consequence of other abnormalities (structural or motility disorders) of the small intestine (see Box 48-4). Use of PPIs is associated with an increased risk of bacterial colonization. 

Over millions of years, some animals evolved a specialized pouch in their digestive tracts to house these bacteria. This pouch—a fermentation sac—can either be located at the front end of the digestive tract, where it is called the rumen, or at the far end of the digestive tract, where it is called the large intestine or cecum. In these fermentation sacs, the cellulolytic bacteria happily do their thing and in turn, produce nutritional products that can be absorbed and used by the host animal for its own metabolism. Thus the ruminant or horse or alpaca or any animal housing these bacteria (including, to a small extent, humans) can obtain nutritional value from cellulose. 

The absorption of p-coumaric acid was shown in the rat gut after the feeding of spinach ceU walls with " C-labeled ferufic and p-coumaric acids to rats [32]. The two fi ee hydroxycinnamic acids were absorbed after release from the ceU wall in the cecum and colon, a finding that strongly suggested an involvement of colonic bacteria. In an in vitro smdy of the absorption of polyphenols using isolated small intestine from the rat, p-coumaric acid was absorbed to a higher extent than caffeic acid and to a lower extent than ferufic acid [25]. Glucuronidation of p-coumaric acid in the epithelium of the rat... 

El-Arab, A.E., Foheid, S., and El-Said, M. 2009. Effect of yeast and botanical [Lglucan on serum lipid profile and cecum probiotic bacteria using rats fed cholesterol diet Polish Journal of... 

Sanders ME (1988) Phage resistanceinlacticacidbacteria. Biochimie 70 411-422 Schoeni JL, Doyle MP (1992) Reduction of Campylobacter jejuni colonization of chicks by cecum-colonizing bacteria producing anti-C. jejuni metabolites. Appl Environ Microbiol 58 664 -670... 

Gong, 1., Forster, R.J., Yu, H., et al. (2002) Molecular analysis of bacterial populations in the ileum of broiler chickens and comparison with bacteria in the cecum. FEMS Microbiol Ecol 41,171-179. 

Salanitro, J.P., Blake, I.G., Muirehead, P.A., et al. (1978) Bacteria isolated from the duodenum, ileum, and cecum of young chicks. Appl Environ Microbiol 35, 782-790. 

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