title: Effects of Lactobacillus casei Shirota, Bifidobacterium breve, and oligofructose-enriched inulin on colonic nitrogen-protein metabolism in healthy humans.
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.
authors.affiliation: Department of Gastrointestinal Research, University Hospital Gasthuisberg, Leuven, Belgium.
authors.forename: Vicky
authors.initials: V
authors.lastname: De Preter
authors.forename: Tom
authors.initials: T
authors.lastname: Vanhoutte
authors.forename: Geert
authors.initials: G
authors.lastname: Huys
authors.forename: Jean
authors.initials: J
authors.lastname: Swings
authors.forename: Luc
authors.initials: L
authors.lastname: De Vuyst
authors.forename: Paul
authors.initials: P
authors.lastname: Rutgeerts
authors.forename: Kristin
authors.initials: K
authors.lastname: Verbeke
mesh_terms: D000328:Adult; D001644:Bifidobacterium / Q000502:physiology*; D003106:Colon / Q000378:metabolism*; D018592:Cross-Over Studies; D005260:Female; D005612:Freeze Drying; D005772:Gastrointestinal Transit; D006801:Humans; D007444:Inulin / Q000494:pharmacology*; D007780:Lacticaseibacillus casei / Q000502:physiology*; D008297:Male; D009584:Nitrogen / Q000652:urine; D009844:Oligosaccharides / Q000494:pharmacology*; D011092:Polyethylene Glycols / Q000378:metabolism; D019936:Probiotics; D011506:Proteins / Q000378:metabolism*; D012016:Reference Values
chemical_list: D009844:Oligosaccharides; D011506:Proteins; C120489:oligofructose; D011092:Polyethylene Glycols; D007444:Inulin; D009584:Nitrogen