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Ethanol Production by Selected Intestinal Microorganisms and Lactic Acid Bacteria Growing under Different Nutritional
Fouad M F Elshaghabee1, Wilhelm Bockelmann2, Diana Meske2
1Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food)Kiel, Germany; Department of Dairy Science, Faculty of Agriculture, Cairo UniversityGiza, Egypt.
Frontiers in Microbiology
|February 10, 2016
Summary
Certain gut bacteria, like Weissella confusa, may promote non-alcoholic fatty liver disease (NAFLD) by producing ethanol from sugar fermentation. Other bacteria and dietary factors may influence NAFLD development.
Area of Science:
- Microbiology
- Gastroenterology
- Metabolic Diseases
Background:
- Non-alcoholic fatty liver disease (NAFLD) is a growing health concern.
- The role of the gut microbiota in NAFLD pathogenesis is increasingly recognized.
- Understanding microbial ethanol production is crucial for NAFLD research.
Purpose of the Study:
- To investigate the ethanol production capabilities of various intestinal microorganisms.
- To determine the influence of different carbohydrates on microbial ethanol synthesis.
- To assess the potential role of specific bacteria in promoting NAFLD through ethanol production.
Main Methods:
- High-performance liquid chromatography (HPLC) was used to quantify ethanol production.
- Ten microbial strains (yeast and bacteria) were cultured on diverse carbohydrates (hexoses, pentoses, disaccharides, inulin).
- Fecal slurries from overweight volunteers were analyzed for ethanol production with and without microbial and metabolite additions.
Main Results:
- Saccharomyces cerevisiae, Lactobacillus fermentum, and Weissella confusa showed high ethanol production on glucose and fructose.
- Ethanol production was reduced by mannitol-dehydrogenase activity in L. fermentum and by pyruvate/citrate additions.
- In fecal slurries, fructose addition increased ethanol production, while W. confusa significantly enhanced it, and other bacteria/metabolites reduced it.
Conclusions:
- Weissella confusa, a hetero-fermentative, mannitol-dehydrogenase negative bacterium, may promote NAFLD via ethanol production from sugar fermentation.
- Other intestinal bacteria, particularly mannitol-dehydrogenase positive ones, may not contribute to NAFLD in the same way.
- Dietary factors influencing gut microbiota and metabolism are critical in NAFLD prevention or progression.
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