Xylo-oligosaccharide (XOS) in combination with inulin modulates both the intestinal environment and immune status in healthy subjects, while XOS alone only shows prebiotic properties

TLDR

The study aimed to evaluate the prebiotic effects of XOS alone and in combination with inulin on gut microbiota, endotoxaemia, and immune markers in healthy volunteers. Sixty healthy volunteers were randomized in a double‑blind, placebo‑controlled trial to receive 5 g XOS, 3 g inulin + 1 g XOS, or maltodextrin for four weeks, with fecal and blood samples collected to assess microbiota, SCFA, enzyme activity, sIgA, plasma LPS, and cytokine responses. XOS alone increased bifidobacteria, butyrate, and glycosidase activities while lowering acetate and p‑cresol, whereas XOS plus inulin raised total SCFA and propionate, reduced circulating LPS, and mitigated LPS‑induced IL‑1β and IL‑13 expression, demonstrating distinct yet beneficial microbiome and anti‑inflammatory effects.

Abstract

The purpose of the present study was to establish the prebiotic effect of a new xylo-oligosaccharide (XOS) and of an inulin-and-XOS mixture (INU–XOS) and to determine their effect on endotoxaemia (lipopolysaccharides (LPS)) and immune parameters. In this randomised, parallel, placebo-controlled, double-blind study, sixty healthy volunteers were randomly assigned to three groups, receiving either 5 g XOS, INU–XOS (3 g inulin +1 g XOS) or an equivalent weight of wheat maltodextrin (placebo) during 4 weeks. Faecal samples were collected to assess the effects of these products on microbiota, as well as SCFA composition, enzymatic activities and secretory IgA production. Circulating LPS was measured in plasma samples, and whole blood was incubated with LPS to measure cytokine expression. Consumption of XOS alone increased the faecal concentrations of Bifidobacterium and butyrate and activities of α-glucosidase and β-glucuronidase, while decreasing the concentrations of acetate and p -cresol. Consumption of XOS in combination with inulin did not decrease the concentrations of acetate and p -cresol, but increased in addition the faecal concentrations of total SCFA and propionate. Furthermore, consumption of XOS in combination with inulin decreased LPS concentrations in blood and attenuated LPS-induced increases in gene expression in IL-1β and LPS-induced decreases in gene expression in IL-13 in blood. In conclusion, consumption of XOS alone or in combination with inulin results in beneficial albeit different changes in the intestinal microbiome on a high-fat diet. In addition, consumption of XOS in combination with inulin attenuates the proinflammatory effects of a high-fat diet in the blood of healthy subjects.