title: Administration of transgalacto-oligosaccharides increases fecal bifidobacteria and modifies colonic fermentation metabolism in healthy humans.
abstract: Transgalacto-oligosaccharides are a mixture of oligosaccharides consisting of glucose and galactose; they are not digested in the human small intestine. In vitro, they specifically stimulate the growth of bifidobacteria. The aim of the present work was to assess tolerance of transgalacto-oligosaccharides and the effects of their prolonged administration on bifidobacteria and fermentative activity of colonic flora. Eight healthy subjects were given 10 g of transgalacto-oligosaccharides per day for 21 d in two daily doses. A breath test and stool sample collection were carried out on d 1, 7, 14 and 21 of transgalacto-oligosaccharides ingestion. The stools of three subjects were collected and mixed before the study, and then inoculated in vitro into a fermentor to which 10 g transgalacto-oligosaccharides was added daily for 14 d. In the eight volunteers, administration of transgalacto-oligosaccharides led to a significant decrease in breath hydrogen excretion (P < 0.01) and a significant increase in fecal concentrations of bifidobacteria from (means +/- SEM) 8.6 +/- 0.6 to 9.7 +/- 0.5, 9.7 +/- 0.6 and 9.5 +/- 0.6 log colony-forming units (CFU)/g on d 1, 7, 14 and 21, respectively (P < 0.05). Fecal concentrations of enterobacteria, as well as stool weight, fecal water and pH did not change during the study. In vitro, transgalacto-oligosaccharides fermentation became more efficient and faster with time. In addition, metabolic alterations such as a rise in acetate proportion and lactate formation after 7 d of fermentation were observed, indicating the transformation of the inoculated fecal flora into an acid-resistant lactic flora. Prolonged administration of transgalacto-oligosaccharides, at a dose which does not induce digestive symptoms, increases the number of bifidobacteria and alters the fermentative activity of colonic flora in humans.
authors.affiliation: INSERM U290, Hôpital Saint-Lazare, Paris, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Bouhnik
authors.forename: B
authors.initials: B
authors.lastname: Flourié
authors.forename: L
authors.initials: L
authors.lastname: D'Agay-Abensour
authors.forename: P
authors.initials: P
authors.lastname: Pochart
authors.forename: G
authors.initials: G
authors.lastname: Gramet
authors.forename: M
authors.initials: M
authors.lastname: Durand
authors.forename: J C
authors.initials: JC
authors.lastname: Rambaud
mesh_terms: D000328:Adult; D001644:Bifidobacterium / Q000302:isolation & purification*; D001944:Breath Tests; D003106:Colon / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology; D005232:Fatty Acids, Volatile / Q000032:analysis; D005243:Feces / Q000382:microbiology*; D005260:Female; D005285:Fermentation / Q000187:drug effects; D005690:Galactose / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D008697:Methane / Q000032:analysis; D009844:Oligosaccharides / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D005232:Fatty Acids, Volatile; D009844:Oligosaccharides; D006859:Hydrogen; D005947:Glucose; D008697:Methane; D005690:Galactose