title: Short-chain fatty acid formation in the hindgut of rats fed native and fermented oat fibre concentrates.
abstract: The formation of SCFA in rats fed fermented oat fibre concentrates was compared with that of rats fed native oat fibre concentrate. The cultures used were lactic acid bacteria consisting of Lactobacillus bulgaricus and Streptococcus thermophilus (V2), the exopolysaccharide-producing strain Pediococcus damnosus 2.6 (Pd) and L. reuteri (Lr). The materials were incorporated into test diets yielding a concentration of indigestible carbohydrates of 80 g/kg (dry weight). Rats fed the V2-fermented fibre-concentrate diet yielded higher caecal and distal concentrations of acetic acid (P < 0.01) than rats fed the native fibre concentrate. All the fermented fibre concentrates resulted in a higher propionic acid concentration in the distal colon (P < 0.05), while rats fed Pd-fermented fibre concentrate resulted in lower concentration of butyric acid (P < 0.05, P < 0.01) in all parts of the hindgut as compared with rats fed the native fibre concentrates. Butyrate concentrations ranged between 5-11 micromol/g (distal colon) and 6-8 micromol/g (13 d faeces). Higher proportions of acetic acid (P < 0.05; P < 0.01) were observed in the caecum of rats fed the fermented fibre concentrates. Rats fed Pd- and Lr-fermented fibre concentrates produced higher proportions of propionic acid (P < 0.05; P < 0.01) in the caecum. Changes in SCFA formation in the caecum, distal colon and faeces of rats fed the fermented samples compared with the native sample indicate that these microbes probably survive in the hindgut and that modification of the microflora composition with fermented foods is possible. This may be important for the gastrointestinal flora balance in relation to colonic diseases.
authors.affiliation: Division of Applied Nutrition and Food Chemistry, Department of Food Technology, Engineering and Nutrition, Center for Chemistry and Chemical Engineering, Lund University, SE-221 00, Lund, Sweden. adele.lambo@inl.lth.se
authors.forename: Adele M
authors.initials: AM
authors.lastname: Lambo-Fodje
authors.forename: Rickard
authors.initials: R
authors.lastname: Oste
authors.forename: Margareta E G-L
authors.initials: ME
authors.lastname: Nyman
mesh_terms: D019342:Acetic Acid / Q000032:analysis; D000818:Animals; D018554:Avena / Q000378:metabolism*; D020148:Butyric Acid / Q000032:analysis; D002432:Cecum / Q000378:metabolism; D003106:Colon / Q000378:metabolism; D004032:Diet; D004043:Dietary Fiber / Q000008:administration & dosage*; D005232:Fatty Acids, Volatile / Q000032:analysis / Q000378:metabolism*; D005243:Feces / Q000737:chemistry; D005285:Fermentation / Q000502:physiology; D007420:Intestine, Large / Q000378:metabolism*; D007778:Lactobacillus; D008297:Male; D010376:Pediococcus; D011422:Propionates / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D048249:Streptococcus thermophilus; D015430:Weight Gain / Q000502:physiology
chemical_list: D004043:Dietary Fiber; D005232:Fatty Acids, Volatile; D011422:Propionates; D020148:Butyric Acid; C029658:propionic acid; D019342:Acetic Acid