title: High dose of prebiotics reduces fecal water cytotoxicity in healthy subjects.
abstract: METHODS
  In vitro and animal studies have shown differential colonic fermentation of structurally different prebiotics. We evaluated the impact of two structurally different prebiotics (wheat bran extract (WBE, containing arabinoxylan-oligosaccharides) and oligofructose) on colonic fermentation and markers of bowel health in healthy volunteers.
  
  
  RESULTS
  Nineteen healthy subjects completed a double-blind, cross-over randomized controlled trial. Interventions with WBE, oligofructose or placebo for 2 wk (week 1: 15 g/day; week 2: 30 g/day) were separated by 2-wk wash-out periods. At the end of each study period, colonic fermentation was characterized through a metabolomics approach. Fecal water genotoxicity and cytotoxicity were determined using the comet and WST-1 assay, respectively, as parameters of gut health. Cluster analysis revealed differences in effects of WBE and oligofructose on colonic fermentation. WBE, but not oligofructose, reduced fecal p-cresol (p = 0.009) and isovaleric acid concentrations (p = 0.022), markers of protein fermentation. Fecal water cytotoxicity was significantly lower after intake of WBE (p = 0.015). Both WBE- and oligofructose-intake tended to reduce fecal water genotoxicity compared to placebo (WBE: p = 0.060; oligofructose: p = 0.057). Changes in fermentation were not related to changes in fecal water toxicity.
  
  
  CONCLUSIONS
  Structurally different prebiotics affect colonic fermentation and gut health in a different way.
authors.affiliation: Translational Research Center for Gastrointestinal Disorders (TARGID), KULeuven, Leuven, Belgium; Leuven Food Science and Nutrition Research Centre (LFoRCe), KULeuven, Leuven, Belgium.
authors.forename: Karen
authors.initials: K
authors.lastname: Windey
authors.forename: Isabelle
authors.initials: I
authors.lastname: François
authors.forename: Willem
authors.initials: W
authors.lastname: Broekaert
authors.forename: Vicky
authors.initials: V
authors.lastname: De Preter
authors.forename: Jan A
authors.initials: JA
authors.lastname: Delcour
authors.forename: Thierry
authors.initials: T
authors.lastname: Louat
authors.forename: Jean
authors.initials: J
authors.lastname: Herman
authors.forename: Kristin
authors.initials: K
authors.lastname: Verbeke
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001834:Body Water / Q000737:chemistry*; D003106:Colon / Q000378:metabolism; D020552:Comet Assay; D018592:Cross-Over Studies; D004249:DNA Damage; D004311:Double-Blind Method; D005243:Feces / Q000737:chemistry* / Q000382:microbiology*; D005260:Female; D005285:Fermentation; D005500:Follow-Up Studies; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D009844:Oligosaccharides / Q000008:administration & dosage; D056692:Prebiotics; D014990:Xylans / Q000008:administration & dosage; D055815:Young Adult
chemical_list: D009844:Oligosaccharides; D056692:Prebiotics; D014990:Xylans; C120489:oligofructose; C085118:arabinoxylan
keywords: Arabinoxylan-oligosaccharides; Fecal water toxicity; Fermentation; Oligofructose