Metabolic Fate of ¹³C-Labeled Polydextrose and Impact on the Gut Microbiome: A Triple-Phase Study in a Colon Simulator

Abstract

The present study introduces a novel triple-phase (liquids, solids, and gases) approach, which employed uniformly labeled [U-C] polydextrose (PDX) for the selective profiling of metabolites generated from dietary fiber fermentation in an in vitro colon simulator using human fecal inocula. Employing C NMR spectroscopy, [U-C] PDX metabolism was observed from colonic digest samples. The major C-labeled metabolites generated were acetate, butyrate, propionate, and valerate. In addition to these short-chain fatty acids (SCFAs),C-labeled lactate, formate, succinate, and ethanol were detected in the colon simulator samples. Metabolite formation and PDX substrate degradation were examined comprehensively over time (24 and 48 h). Correlation analysis between C NMR spectra and gas production confirmed the anaerobic fermentation of PDX to SCFAs. In addition, 16S rRNA gene analysis showed that the level of Erysipelotrichaceae was influenced by PDX supplementation and Erysipelotrichaceae level was statistically correlated with SCFA formation. Overall, our study demonstrates a novel approach to link substrate fermentation and microbial function directly in a simulated colonic environment.

A blend of 3 mushrooms dose-dependently increases butyrate production by the gut microbiota

“…Moreover, also Erysipelotrichaceae has been shown to be stimulated by fibre intake (e.g. Lamichhane et al, 2018), and in this study with 13 C-labelled polydextrose was correlated with increased SCFA production.…”

“…However, as mentioned above we cannot exclude that the metabolism of certain taxa changed (from acetate/propionate to butyrate), without major shifts in composition. Future studies with 13 C-labelled substrates, similar to the ones done by us and others before, might shed a light on that (Binsl et al, 2010;de Graaf et al, 2010;Lamichhane et al, 2018).…”

Simultaneous Intake of Euglena Gracilis and Vegetables Synergistically Exerts an Anti-Inflammatory Effect and Attenuates Visceral Fat Accumulation by Affecting Gut Microbiota in Mice

“…The fraction of the bacterial subclass Erysipelotrichaceae; Other has been shown to increase following the consumption of β-glucans and inulin [ 34 ]. These bacteria participate in the production of short-chain fatty acids [ 35 ]. In the present study, the fraction of Erysipelotrichaceae; Other was increased by the consumption of vegetables rich in soluble dietary fiber, which also caused an actual increase in short-chain fatty acid concentrations.…”

Metabolomics analysis of plasma and adipose tissue samples from mice orally administered with polydextrose and correlations with cecal microbiota

“…A study using 13 C-labeled PDX showed that the major 13 C-labeled metabolites in colon simulator samples were acetate, butyrate, propionate, and valerate. In addition, minor amounts of 13 C-labeled lactate, formate, and succinate were detected 14 . Another in vitro human colon simulator study using PDX 15 showed higher levels of acetate, butyrate, propionate, and succinate, and lower levels of certain amino acids, valerate, formate, isovalerate, and trimethylamine in PDX samples compared to control samples.…”