title: Interactions of a lignin-rich fraction from brewer's spent grain with gut microbiota in vitro.
abstract: Lignin is a constituent of plant cell walls and thus is classified as part of dietary fiber. However, little is known about the role of lignin in gastrointestinal fermentation. In this work, a lignin-rich fraction was prepared from brewer's spent grain and subjected to an in vitro colon model to study its potential bioconversions and interactions with fecal microbiota. No suppression of microbial conversion by the fraction was observed in the colon model, as measured as short-chain fatty acid production. Furthermore, no inhibition on the growth was observed when the fraction was incubated with strains of lactobacilli and bifidobacteria. In fact, the lignin-rich fraction enabled bifidobacteria to survive longer than with glucose. Several transiently appearing phenolic compounds, very likely originating from lignin, were observed during the fermentation. This would indicate that the gut microbiota was able to partially degrade lignin and metabolize the released compounds.
authors.affiliation: Bio and Process Technology, VTT Technical Research Centre of Finland , P.O. Box 1000, FI-02044 VTT Espoo, Finland.
authors.forename: Piritta
authors.initials: P
authors.lastname: Niemi
authors.forename: Anna-Marja
authors.initials: AM
authors.lastname: Aura
authors.forename: Johanna
authors.initials: J
authors.lastname: Maukonen
authors.forename: Annika I
authors.initials: AI
authors.lastname: Smeds
authors.forename: Ismo
authors.initials: I
authors.lastname: Mattila
authors.forename: Klaus
authors.initials: K
authors.lastname: Niemelä
authors.forename: Tarja
authors.initials: T
authors.lastname: Tamminen
authors.forename: Craig B
authors.initials: CB
authors.lastname: Faulds
authors.forename: Johanna
authors.initials: J
authors.lastname: Buchert
authors.forename: Kaisa
authors.initials: K
authors.lastname: Poutanen
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D003106:Colon / Q000378:metabolism / Q000382:microbiology*; D002523:Edible Grain / Q000737:chemistry / Q000378:metabolism*; D005243:Feces / Q000382:microbiology; D005285:Fermentation; D006801:Humans; D008031:Lignin / Q000032:analysis / Q000378:metabolism*; D064307:Microbiota; D008954:Models, Biological; D014866:Waste Products / Q000032:analysis*
chemical_list: D014866:Waste Products; D008031:Lignin