The fate of ¹³C-labelled and non-labelled inulin predisposed to large bowel fermentation in rats

Abstract

The fate of stable-isotope (13)C labelled and non-labelled inulin catabolism by the gut microbiota was assessed in a healthy rat model. Sprague-Dawley male rats were randomly assigned to diets containing either cellulose or inulin, and were fed these diets for 3 days. On day (d) 4, rats allocated to the inulin diet received (13)C-labelled inulin. The rats were then fed the respective non-labelled diets (cellulose or inulin) until sampling (d4, d5, d6, d7, d10 and d11). Post feeding of (13)C-labelled substrate, breath analysis showed that (13)C-inulin cleared from the host within a period of 36 hours. Faecal (13)C demonstrated the clearance of inulin from gut with a (13)C excess reaching maximum at 24 hours (d5) and then declining gradually. There were greater variations in caecal organic acid concentrations from d4 to d6, with higher concentrations of acetic, butyric and propionic acids observed in the rats fed inulin compared to those fed cellulose. Inulin influenced caecal microbial glycosidase activity, increased colon crypt depth, and decreased the faecal output and polysaccharide content compared to the cellulose diet. In summary, the presence of inulin in the diet positively influenced large bowel microbial fermentation.

Stable Isotope Tracing In Vivo Reveals A Metabolic Bridge Linking The Microbiota To Host Histone Acetylation

“…5A, 5C). Consistent with previous literature, inulin underwent fermentation into SCFAs (Deroover et al, 2017;Butts et al, 2016) (Supplemental Fig. 5B).…”

“…To test whether butyrate serves as a carbon source for histone acetylation in a more physiological model, we treated mice with isotope-labeled, fermentable fiber (U-13 C-inulin). Inulin is known to be metabolized into short-chain fatty acids (SFCAs), including butyrate (Deroover et al, 2017;Butts et al, 2016). Thus, we predicted that the microbiota would ferment inulin into butyrate, which would then be oxidized by gut epithelial cells into acetyl-CoA for use by HATs (Fig.…”

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

“…Stable isotope labeling provides an excellent approach for tracking the conversion of the substrate and identifying resultant metabolic products, thus allowing a rapid and comprehensive profiling of selective microbial activity. 10 An approach using uniformly labeled [U− 13 C] substrate also offers a robust method to elucidate the metabolic pathways involved in the microbial metabolism. In fact, previous studies based on stable isotope labeling have shown the usefulness of [U− 13 C] approaches.…”

“…10 An approach using uniformly labeled [U− 13 C] substrate also offers a robust method to elucidate the metabolic pathways involved in the microbial metabolism. In fact, previous studies based on stable isotope labeling have shown the usefulness of [U− 13 C] approaches. For instance, de Graaf et al introduced 13 C enrichment as an approach to evaluate the kinetics of To characterize the metabolic process of dietary fiber catabolism, an in vitro colon simulator offers the advantage of enabling dynamic sampling and implies substantially fewer ethical issues compared with an in vivo study.…”

Synthesis and characterization of calcium phosphorylated inulin complex as a new source of enriched calcium supplement with prebiotic effect in food

“…Onulin is a non-branched polydisperse fructan that mainly consists of β(2→1) linked fructose units with a glucose unit at the reducing end (Morros et al, 2011;Lingyun et al, 2007). Ot belongs to a class of fibers known as non-digestible oligosaccharide that improve or maintain colon health as a prebiotic (Dewulf et al, 2013;Miremadi & Shah, 2012;Butts et al, 2016). Dver the last few decades, inulin has been modified by various methods to achieve functionalities suitable for various applications such as carboxymethylinulin, inulin-D-α-tocopherol succinate, p(inulin) microgel (Verraest et al, 1995;Mandracchia et al, 2014;Sahiner & Sagbas, 2014).…”