title: Levan Enhances Associated Growth of Bacteroides, Escherichia, Streptococcus and Faecalibacterium in Fecal Microbiota.
abstract: The role of dietary fiber in supporting healthy gut microbiota and overall well-being of the host has been revealed in several studies. Here, we show the effect of a bacterial polyfructan levan on the growth dynamics and metabolism of fecal microbiota in vitro by using isothermal microcalorimetry. Eleven fecal samples from healthy donors were incubated in phosphate-buffered defined medium with or without levan supplementation and varying presence of amino acids. The generation of heat, changes in pH and microbiota composition, concentrations of produced and consumed metabolites during the growth were determined. The composition of fecal microbiota and profile of metabolites changed in response to substrate (levan and amino acids) availability. The main products of levan metabolism were acetic, lactic, butyric, propionic and succinic acids and carbon dioxide. Associated growth of levan-degrading (e.g. Bacteroides) and butyric acid-producing (e.g. Faecalibacterium) taxa was observed in levan-supplemented media. The study shows that the capacity of levan and possibly also other dietary fibers/prebiotics to modulate the composition and function of colon microbiota can be predicted by using isothermal microcalorimetry of fecal samples linked to metabolite and consortia analyses.
authors.affiliation: Department of Food Processing, Tallinn University of Technology, 19086 Tallinn, Estonia.|Competence Center of Food and Fermentation Technologies, 12618 Tallinn, Estonia.
authors.forename: Kaarel
authors.initials: K
authors.lastname: Adamberg
authors.affiliation: Competence Center of Food and Fermentation Technologies, 12618 Tallinn, Estonia.
authors.forename: Katrin
authors.initials: K
authors.lastname: Tomson
authors.affiliation: Competence Center of Food and Fermentation Technologies, 12618 Tallinn, Estonia.
authors.forename: Tiina
authors.initials: T
authors.lastname: Talve
authors.affiliation: Competence Center of Food and Fermentation Technologies, 12618 Tallinn, Estonia.
authors.forename: Ksenia
authors.initials: K
authors.lastname: Pudova
authors.affiliation: Department of Food Processing, Tallinn University of Technology, 19086 Tallinn, Estonia.
authors.forename: Marju
authors.initials: M
authors.lastname: Puurand
authors.affiliation: Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia.|Department of Systems Biology, Technical University of Denmark, Elektrovej, building 375, 2800 Kgs. Lyngby, Denmark.
authors.forename: Triinu
authors.initials: T
authors.lastname: Visnapuu
authors.affiliation: Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia.
authors.forename: Tiina
authors.initials: T
authors.lastname: Alamäe
authors.affiliation: Department of Food Processing, Tallinn University of Technology, 19086 Tallinn, Estonia.
authors.forename: Signe
authors.initials: S
authors.lastname: Adamberg
mesh_terms: D001439:Bacteroides / Q000187:drug effects* / Q000254:growth & development; D004925:Escherichia / Q000187:drug effects* / Q000235:genetics; D005243:Feces / Q000382:microbiology*; D005630:Fructans / Q000494:pharmacology*; D013291:Streptococcus / Q000187:drug effects* / Q000235:genetics
chemical_list: D005630:Fructans; C072599:levan