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Dietary fat and the human gut microbiome

  • January 2013
Authors:
Rosemarie De Weirdt
Rosemarie De Weirdt
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The aim of this doctoral work was to investigate the effect of an increased level of fat in the Western diet on the composition and metabolic activity of the colon microbiota. Specific interest thereby went to two ‘fatty’ compounds: glycerol and the omega-6 polyunsaturated fatty acid linoleic acid. In vitro experiments were performed with various models of the human gut microbiota. In addition, a model of the colon epithelium was used to study the effect of glycerol fermentation on infection by Salmonella. Using these models, it was demonstrated that glycerol and linoleic acid may significantly impact microbial processes and species that are associated with human health. Glycerol fermentation was found to protect against pathogenic infection, while high levels of linoleic acid were considered a threat for the prevalence and activity of beneficial microbes. These detrimental effects were dependent on the presence of a simulated mucus layer. Overall, the results of this doctoral research demonstrate that an increased delivery of fat to the colon may significantly impact health-related microbial processes. These novel findings underpin the need for further in vivo research concerning the impact of colonic fat for human health.
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... The extent of LA biohydrogenation in the M-SHIME is currently investigated in our group. The LCFA composition on day 1 of the M-and L-SHIME vessels exposed to 1 g/l LA indeed showed a higher conversion of LA to VA in the M-SHIME (De Weirdt, 2013). LA conversion to VA was similar in both the lumen and the mucin-agar compartment of the M-SHIME. ...
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  • Dec 2013
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Chapter
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