QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Fernandes, J. Articles by Wolever, T. M. S. Search for Related Content PubMed PubMed Citation Articles by Fernandes, J. Articles by Wolever, T. M. S.

---

Article

Different Substrates and Methane Producing Status Affect Short-Chain Fatty Acid Profiles Produced by In Vitro Fermentation of Human Feces^{1 ,2}

Judlyn Fernandes^*, A. Venketeshwer Rao^* and Thomas M. S. Wolever^*,3

^* Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Canada M5S 3E2 and Clinical Nutrition and Risk Factor Modification Centre and Division of Endocrinology and Metabolism, St. Michael’s Hospital, Toronto, Canada M5C 2T2

³To whom correspondence should be addressed.

Five different substrates, i.e., lactulose, rhamnose, cornstarch, guar and ileostomy effluent, were used to determine whether methane producing status alters the production of short-chain fatty acids (SCFA) in methane producers (MP; n = 6) and nonproducers (MNP; n = 5). Fecal samples from MP and MNP were fermented with the five substrates using an in vitro fermentation method. Subjects with a mean breath methane concentration > 0.045 µmol/L above ambient air were classified as MP. Fermentation was stopped and samples were obtained at 3, 5 and 24 h. An HPLC method was used to measure the SCFA, acetate, propionate, isobutyrate, butyrate, valerate and isocaproate. A significant interaction between methane producing status and time for acetate production from lactulose was observed. There were no differences in fermentation of the four remaining substrates between MP and MNP, but there were significant differences among substrates in the two groups combined. Acetate production from lactulose was significantly greater than from the four other substrates, whereas that from ileostomy effluent was significantly less than the four other substrates. The amount of propionate produced from rhamnose was significantly higher than from the other substrates. The amount of butyrate produced from lactulose and cornstarch was significantly higher than from the other substrates. We conclude that differences exist in the fermentation patterns of lactulose, rhamnose, cornstarch, guar and ileostomy effluent. Methane producing status may influence fermentation patterns only of substrates that are largely fermented to acetate and not others.

KEY WORDS: • humans • methane • short-chain fatty acids • in vitro fermentation

This article has been cited by other articles:

				J. A. Vogt, K. B. Ishii-Schrade, P. B. Pencharz, P. J. H. Jones, and T. M. S. Wolever L-Rhamnose and Lactulose Decrease Serum Triacylglycerols and Their Rates of Synthesis, but Do Not Affect Serum Cholesterol Concentrations in Men J. Nutr., August 1, 2006; 136(8): 2160 - 2166. [Abstract] [Full Text] [PDF]

				J. A Vogt, K. B Ishii-Schrade, P. B Pencharz, and T. M. Wolever L-Rhamnose increases serum propionate after long-term supplementation, but lactulose does not raise serum acetate Am. J. Clinical Nutrition, November 1, 2004; 80(5): 1254 - 1261. [Abstract] [Full Text] [PDF]

				J. A Vogt, P. B Pencharz, and T. M. Wolever L-Rhamnose increases serum propionate in humans Am. J. Clinical Nutrition, July 1, 2004; 80(1): 89 - 94. [Abstract] [Full Text] [PDF]

				J. A. Vogt and T. M. S. Wolever Fecal Acetate Is Inversely Related to Acetate Absorption from the Human Rectum and Distal Colon J. Nutr., October 1, 2003; 133(10): 3145 - 3148. [Abstract] [Full Text] [PDF]

				T. M. Wolever, K. B Schrade, J. A Vogt, E. B Tsihlias, and M. I McBurney Do colonic short-chain fatty acids contribute to the long-term adaptation of blood lipids in subjects with type 2 diabetes consuming a high-fiber diet? Am. J. Clinical Nutrition, June 1, 2002; 75(6): 1023 - 1030. [Abstract] [Full Text] [PDF]