title: Prolonged intake of fructo-oligosaccharides induces a short-term elevation of lactic acid-producing bacteria and a persistent increase in cecal butyrate in rats.
abstract: While the prebiotic effects of fructo-oligosaccharides (FOS), short-chain polymers of fructose, have been thoroughly described after 2-3 wk of ingestion, effects after intake for several months are unknown. We tested the hypothesis that these effects would differ after ingestion for short and long periods in rats. Rats were fed a basal low-fiber diet (Basal) or the same diet containing 9 g/100 g of FOS for 2, 8 or 27 wk, and cecal contents were collected at the end of each time period. Cecal short-chain fatty acid concentration was higher in rats fed FOS than in those fed Basal, and this effect persisted over time: 83.8 +/- 4.1 vs. 62.4 +/- 6.5 micromol/g at 2 wk and 103.5 +/- 5.8 vs. 73.2 +/- 7.4 micromol/g at 27 wk (P < 0.05). The molar butyrate ratio was higher in rats fed FOS regardless of the time period (14.8 +/- 0.6% vs. 6.7 +/- 1.1% at 27 wk, P < 0.05). Lactate concentration in rats fed FOS was elevated after 2 wk and then decreased: 63.5 +/- 21.6 micromol/g at 2 wk vs. 8.8 +/- 3.3 micromol/g at 8 wk (P < 0.05). After 2 wk, FOS increased the concentrations of total lactic acid-producing bacteria, and Lactobacillus sp. (P < 0.05), without modifying total anaerobes. However, most of these effects were abolished after 8 and 27 wk of FOS consumption. In the long term, the FOS-induced increase in intestinal lactic acid-producing bacteria was lost, but the butyrogenic properties of FOS were maintained.
authors.affiliation: Human Nutrition Research Centre, Institut National de la Recherche Agronomique, BP 71627, 44316 Nantes Cedex 03, France.
authors.forename: G
authors.initials: G
authors.lastname: Le Blay
authors.forename: C
authors.initials: C
authors.lastname: Michel
authors.forename: H M
authors.initials: HM
authors.lastname: Blottière
authors.forename: C
authors.initials: C
authors.lastname: Cherbut
mesh_terms: D000818:Animals; D001419:Bacteria / Q000254:growth & development* / Q000378:metabolism*; D002087:Butyrates / Q000378:metabolism*; D002432:Cecum / Q000378:metabolism*; D015169:Colony Count, Microbial; D005232:Fatty Acids, Volatile / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000096:biosynthesis* / Q000378:metabolism; D008297:Male; D009844:Oligosaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D002087:Butyrates; D005232:Fatty Acids, Volatile; D009844:Oligosaccharides; C116580:fructooligosaccharide; D019344:Lactic Acid