Fermentable dietary fiber, influence

The Influence of Fermentable Dietary Fiber on the Disposition and Toxicity of Xenobiotics... 

Our first indication that fermentable fiber could alter microfloral metabolism was based on studies assessing the influence of dietary fiber types on the disposition of model xenobiotics using pharmacokinetic analysis (14). Amaranth was selected as a model xenobiotic for these studies because it was absorbed only after reduction by gut microflora (15). 

Variation in the fermentable fiber content of diets used in toxicity studies and in human diets may influence the toxicity of xenobiotics metabolized by the intestinal microflora. These results emphasize the importance of characterizing the fiber in diets when investigating the influence of dietary fiber on disease processes and chemical toxicity. 

Debethizy JD, Goldstein RS. 1985. The influence of fermentable dietary fiber on the disposition and toxicity of xenobiotics. In Finley JW, Schwass DE, eds. American Chemical Society Symposium Series 277. Xenobiotic metabolism Nutritional effects. Washington, DC American Chemical Society, 37-50. 

Because of the variety of polysaccharides which can be fermented by some Bacteroides species, it is difficult to predict with certainty which polysaccharides in the complex mixture of dietary and host-produced carbohydrates that enter the colon will be degraded most rapidly and most extensively. Further information about how these organisms make choices between different polysaccharides i vitro may help to clarify this issue. However, nutritionists who are interested in catabolism of dietary fiber components iji vivo should be aware that the bacteria may prefer other sources of carbohydrate, such as mucopolysaccharides from host secretions or even Maillard products, to the dietary polysaccharide under study, and that this preference may influence catabolism of a particular polysaccharide in ways which we cannot at present predict. Effects of this sort may be responsible for some of the individual-to-individual variation which is encountered in nutritional studies of dietary fiber utilization. 

Anguita M., N. Canibe, J.F. P ez and B.B. Jensen, 2006. Influence on the amount of dietary fiber on the available energy from hindgut fermentation in growing pigs Use of cannulated pigs and in vitro fermentation. J. Anim. Sci. 84, 2766-2778. 

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