title: Does yogurt enriched with Bifidobacterium longum affect colonic microbiology and fecal metabolites in health subjects?
abstract: Diet-induced changes in the colonic microflora seem to play a role in colon carcinogenesis. In this study the effects of a yogurt (500 mL/d for 3 wk) enriched with Bifidobacterium longum and 5 g lactulose/L (A) on the fecal bacterial flora and various risk indexes for colon carcinogenesis were tested in 12 healthy volunteers and compared with a conventional yogurt (B). Increased excretion of bifidobacteria (P < 0.017) was found after consumption of both yogurts compared with the prestudy periods, whereas cultural counts of aerobes and anaerobes were not different. Breath-hydrogen exhalation was elevated and mouth-to-cecum transit time was accelerated in the period of yogurt A ingestion (P < 0.05) whereas no differences were found for oral-anal mean transit time, stool weight and pH, and fecal concentrations of short-chain fatty acids, bile acids, and neutral sterols. The results generally indicate great stability of the human fecal flora to this kind of dietary intervention.
authors.affiliation: Department of Medicine, University of Wuerzburg, Germany.
authors.forename: H P
authors.initials: HP
authors.lastname: Bartram
authors.forename: W
authors.initials: W
authors.lastname: Scheppach
authors.forename: S
authors.initials: S
authors.lastname: Gerlach
authors.forename: G
authors.initials: G
authors.lastname: Ruckdeschel
authors.forename: E
authors.initials: E
authors.lastname: Kelber
authors.forename: H
authors.initials: H
authors.lastname: Kasper
mesh_terms: D000328:Adult; D001644:Bifidobacterium / Q000502:physiology*; D001647:Bile Acids and Salts / Q000032:analysis; D001944:Breath Tests; D003106:Colon / Q000382:microbiology*; D003672:Defecation; D004032:Diet; D004311:Double-Blind Method; D005232:Fatty Acids, Volatile / Q000032:analysis; D005243:Feces / Q000737:chemistry* / Q000382:microbiology; D005260:Female; D005772:Gastrointestinal Transit; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007792:Lactulose / Q000008:administration & dosage / Q000378:metabolism; D008297:Male; D012119:Respiration / Q000502:physiology; D013261:Sterols / Q000032:analysis; D015014:Yogurt / Q000382:microbiology*
chemical_list: D001647:Bile Acids and Salts; D005232:Fatty Acids, Volatile; D013261:Sterols; D007792:Lactulose; D006859:Hydrogen