Colonic microbiota

GIBSON G R, ROBERFRoiD M B (1995) Dietary modulation of the human colonic microbiota introducing the concept of prebiotics. J Ante 125 1401-12. 

Wroblewski, S., et al. 2000. The influence of a colonic microbiota on HPMA copolymer lectin conjugates binding to rodent intestine. J Drug Target 8 173. 

G. R. Gibson and M. B. Roberfroid (ed), Colonic Microbiota, Nutrition and Health, Kluwer Academic, Dordrecht, 1999. 

Howard, M.D., Gordon, D.T., Pace, L.W., Garleb, K.A., and Kerley, M.S., Effects of dietary supplementation with fructooligosaccharides on colonic microbiota populations and epithelial cell proliferation in neonatal pigs, J. Pediatr. Gastroenterol. Nutr., 21, 297-303, 1995. 

Gibson, G. R and Roberfroid, M. B. (1995). Dietary modulation of the human colonic microbiota Introducing the concept of pnebiotics. /. Nulr. 125,14CH l412. 

Tuohy KM, Ziemer CJ, Klinder A, Knobel Y, Pool-Zobel BL, Gibson GR. A human volunteer study to determine the prebiotic effects of lactulose powder on human colonic microbiota. Microb Ecol Health Dis 2002 14 165-73. 

Fairweather-Tait SJ, Johnson IT (1999) Bioavailability of minerals. In Gibson GR, Roberfroid MB (eds) Colonic microbiota nutrition and health. Kluwer Academic, Dordrecht, p 233 Cashman K (2002) Br J Nutr 87 S169... 

Fuller R. Probiotics in man and animals. J Appl Bacteriol 1989 66 365-378. Gibson GR, Roberfroid MB. Dietary modulation of the human colonic microbiota introducing the concept of prebiotics. J Nutr 1955 125 1401-1412. Gibson GR, Probert HM, Van Foo JAE, Rastall RA, Roberfroid MB. Dietary modulation of the human colonic microbiota updating the concept of prebiotics. Nutr Res Rev 2004 17 259-275. 

Polyphenols undergo extensive bioconversion in the human intestine especially due to the activity of the human colonic microbiota . Unraveling of such co-metabonome interactions is extremely complex due to separation of metabolic events over time and over different (body) compartments. 

The colon contains the most species-rich and densely populated human-associated microbial communities, and the most widely studied. The colonic microbiota comprises many hundreds of bacterial species, 1000s of strains and populations of about 10 cells/g contents. The physiology of the colon renders it a particularly suitable bacterial habitat, as the flow of intestinal digesta slows, allowing bacteria ready access to dietary growth substrates. The pH is moderately acidic in the proximal colon, mainly due to bacterial fermentation itself, and increases to a more neutral pH in the transverse and distal colon with secretions by the host and water absorption. Indeed, using in vitro models of the human gut microbiota, pH has been shown to be a critical modulator of both microbiota composition and metabolic activity under the physicochemical conditions of the human colon. ... 

Walker AW, Ince J, Duncan SH, et al. Dominant and diet-responsive groups of bacteria within the human colonic microbiota. ISME J. 2011 5 220-230. 

The final criterion for a prebiotic is that its fermentation in the colon has some beneficial impact on host health. In vitro studies using models of the colonic microbiota inoculated with human feces and studies in animals, have shown that fermentation of prebiotic fructans leads to accumulation of acetate and butyrate in intestinal/gut model contents. Fermentation of other prebiotics and certain dietary fibers has also been shown to increase propionate production in these systems. Small amounts of lactate and succinate can also be observed using in vitro models, but in vivo, these SCFA are rapidly converted into butyrate and propionate by the gut microbiota. Bifidobacteria and lactobacilli ferment carbohydrates mainly to acetate and lactate, but do not themselves produce butyrate. Recent studies have shown that dominant members of the Firmicutes, Eubacterium halli, Roseburia, Faecalibacterium prausnitzii and Anaerostipes caccae are able to cross-feed off acetate and lactate within the colonic milieu converting them into butyrate, providing a mechanism by which prebiotic modulation of acetate-produdng bifidobacteria can lead to elevated butyrate concentrations within the SCFA have been implicated... 

Jacobs DM, Gaudier E, van Dujmhoven J, Vaughan EE. Non-digestible food ingredients, colonic microbiota and the impact on gut health and immunity a role for metabolomics. Curr Drug Metab. 2009 10 41-54. 

Duncan SH, Lobley GE, Holtrop G, et al. Human colonic microbiota associated with diet, obesity and weight loss. Int J Obesity. 2008 32... 

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