Effects of Lactobacillus casei Shirota, Bifidobacterium breve, and oligofructose-enriched inulin on colonic nitrogen-protein metabolism in healthy humans

Am J Physiol Gastrointest Liver Physiol. 2007 Jan;292(1):G358-68. doi: 10.1152/ajpgi.00052.2006. Epub 2006 Sep 21.

Abstract

Pre- and/or probiotics can cause changes in the ecological balance of intestinal microbiota and hence influence microbial metabolic activities. In the present study, the influence of oligofructose-enriched inulin (OF-IN), Lactobacillus casei Shirota, and Bifidobacterium breve Yakult on the colonic fate of NH3 and p-cresol was investigated. A randomized, placebo-controlled, crossover study was performed in 20 healthy volunteers to evaluate the influence of short- and long-term administration of OF-IN, L. casei Shirota, B. breve Yakult, and the synbiotic L. casei Shirota + OF-IN. The lactose[15N,15N]ureide biomarker was used to study the colonic fate of NH3. Urine and fecal samples were analyzed for 15N content by combustion-isotope ratio mass spectrometery and for p-cresol content by gas chromatography-mass spectrometry. RT-PCR was applied to determine the levels of total bifidobacteria. Both short- and long-term administration of OF-IN resulted in significantly decreased urinary p-cresol and 15N content. The reduction of urinary 15N excretion after short-term OF-IN intake was accompanied by a significant increase in the 15N content of the fecal bacterial fraction. However, this effect was not observed after long-term OF-IN intake. In addition, RT-PCR results indicated a significant increase in total fecal bifidobacteria after long-term OF-IN intake. Long-term L. casei Shirota and B. breve Yakult intake showed a tendency to decrease urinary 15N excretion, whereas a significant decrease was noted in p-cresol excretion. In conclusion, dietary addition of OF-IN, L. casei Shirota, and B. breve Yakult results in a favorable effect on colonic NH3 and p-cresol metabolism, which, in the case of OF-IN, was accompanied by an increase in total fecal bifidobacteria.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Bifidobacterium / physiology*
  • Colon / metabolism*
  • Cross-Over Studies
  • Female
  • Freeze Drying
  • Gastrointestinal Transit
  • Humans
  • Inulin / pharmacology*
  • Lacticaseibacillus casei / physiology*
  • Male
  • Nitrogen / urine
  • Oligosaccharides / pharmacology*
  • Polyethylene Glycols / metabolism
  • Probiotics*
  • Proteins / metabolism*
  • Reference Values

Substances

  • Oligosaccharides
  • Proteins
  • oligofructose
  • Polyethylene Glycols
  • Inulin
  • Nitrogen