Prebiotic inulin-type fructans induce specific changes in the human gut microbiota

Abstract

ObjectiveContrary to the long-standing prerequisite of inducing selective (ie, bifidogenic) effects, recent findings suggest that prebiotic interventions lead to ecosystem-wide microbiota shifts. Yet, a comprehensive characterisation of this process is still lacking. Here, we apply 16S rDNA microbiota profiling and matching (gas chromatography mass spectrometry) metabolomics to assess the consequences of inulin fermentation both on the composition of the colon bacterial ecosystem and faecal metabolites profiles.DesignFaecal samples collected during a double-blind, randomised, cross-over intervention study set up to assess the effect of inulin consumption on stool frequency in healthy adults with mild constipation were analysed. Faecal microbiota composition and metabolite profiles were linked to the study's clinical outcome as well as to quality-of-life measurements recorded.ResultsWhile faecal metabolite profiles were not significantly altered by inulin consumption, our analyses did detect a modest effect on global microbiota composition and specific inulin-induced changes in relative abundances of Anaerostipes, Bilophila and Bifidobacterium were identified. The observed decrease in Bilophila abundances following inulin consumption was associated with both softer stools and a favourable change in constipation-specific quality-of-life measures.ConclusionsEcosystem-wide analysis of the effect of a dietary intervention with prebiotic inulin-type fructans on the colon microbiota revealed that this effect is specifically associated with three genera, one of which (Bilophila) representing a promising novel target for mechanistic research.Trial registration numberNCT02548247.

Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics

“…were additionally elevated, whereas Bilophila spp. decreased 27 . Both studies used high throughput sequencing to confirm selectivity of the prebiotic fermentation.…”

“…Hence, it is recognized today that prebiotic effects probably extend beyond bifidobacteria and lactobacilli, but to meet the selectivity criterion of a prebiotic, the range of microorganisms affected must be limited. To this end, in two human studies that used high throughput sequencing, bifidobacteria responded to prebiotic use 22,27 . However, other groups such as Faecalibacterium prausnitzii also increased in abundance in one trial 22 and in another study Anaerostipes spp.…”

Cross-feeding interactions of gut symbionts driven by human milk oligosaccharidesand mucins

“…(Vandeputte et al 2017). Judging from the metabolic interdependencies of butyrogens and the glycandegrading bacterial species, a cocktail of probiotic strains instead for a strain could be administered to stimulate the beneficial butyrate production.…”

Pea Hull Fiber: A Dietary Fiber to Modulate Gastrointestinal Function and Gut Microbiota

“…For example, provision of 30 g of chemically modified resistant starch to healthy adults did not impact bacterial diversity (7), nor did provision of 15 g of a prebiotic fiber, galacto-oligosaccharide (3). These findings may be due to the stability of the microbiota in healthy participants, or alternatively, purified isolated fibers may not promote increased diversity due to selective fermentation (50). In contrast, dietary fibers may promote increased bacterial diversity due to their Pea Hull Fiber: A Dietary Fiber to Modulate Gastrointestinal Function and Gut Microbiota complex carbohydrate structures, which require a variety of bacterial enzymes for hydrolysis and fermentation.…”