Pectin nitrobenzene

Figure 2. Influence of diet on the time course of nitrobenzene-induced methemoglobinemia. Each point represents X SE of at least three determinations. Astericks and daggers represent a significant difference from AIN-76A and AIN-76A containing 5% pectin groups, respectively (p < 0.05).

In vitro reductive metabolism of 14C-nitrobenzene was significantly greater in the cecal contents of rats fed NIH-07 than that in the cecal contents of either of the groups fed the AIN-76A-based diets (Table V). Furthermore, nitrobenzene metabolism by cecal contents tended to be greatest in animals fed NIH-07, least in animals fed AIN-76A, and intermediate in those fed AIN-76A containing pectin. Metabolites of nitrobenzene produced by cecal contents of animals fed NIH-07 and AIN-76A containing pectin included aniline, nitrosobenzene, and azoxybenzene, whereas aniline was the only detectable metabolite observed in animals fed the AIN-76 A diet (Table V). 

These studies indicate that intestinal microfloral metabolism and red blood cell toxicity of nitrobenzene is markedly different in animals fed cereal-based versus purified diets. Furthermore, since inclusion of pectin into the purified diet diminishes the magnitude of these effects, differences in dietary composition of fermentable carbohydrates in cereal-based and purified diets may mediate differences in metabolism and toxicity of nitrobenzene (27). 

Goldstein RS, Chism JP, Sherrill JM, et al. 1984a. Influence of dietary pectin on intestinal microfloral metabolism and toxicity of nitrobenzene. Toxicol Appl Pharmacal 75 547-553. 

Irons RD, Hamm TE Jr, Rickert DE. 1985. Effect of dietary pectin on the target organ toxicity of nitrobenzene (NB) [Abstract], Toxicologist 5 91. 

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