Xylan and arabinoxylan polysaccharides (AX)

Xylan and arabinoxylan polysaccharides are complex hemicelluloses that constitute a significant portion of the cell walls in terrestrial plants and cereal grains (Scheller & Ulvskov, 2010). In the human diet, these molecules function as non-digestible carbohydrates or dietary fibers, as the human genome lacks the enzymes required for their degradation in the small intestine (Mendonça et al., 2022). Upon reaching the colon, they are fermented by specific members of the gut microbiota, such as Bifidobacterium and Bacteroides species, leading to the production of short-chain fatty acids (SCFAs) like butyrate and propionate (Neyrinck et al., 2011). These SCFAs serve as energy sources for colonocytes and act as signaling molecules that regulate systemic metabolism and immune function (Broekaert et al., 2011). Clinically, arabinoxylans are recognized for their ability to improve insulin sensitivity, lower postprandial glucose levels, and enhance satiety, making them valuable in the management of metabolic disorders like type 2 diabetes and obesity (Mendonça et al., 2022). While they are not traditional pharmacological targets like receptors, they are targeted by exogenous xylanase enzymes in industrial and supplemental applications to improve digestibility and release bioactive xylo-oligosaccharides. Their role in health is primarily mediated through the modulation of the gut environment and the production of metabolic byproducts rather than direct interaction with human protein targets.

Other names

ArabinoxylanXylanAXPentosansHemicelluloseCereal pentosans

Arabinoxylans act as prebiotics that are fermented by colonic bacteria to produce short-chain fatty acids (SCFAs), which then modulate host metabolism via GPCR signaling and improve intestinal barrier function (Mendonça et al., 2022). They also physically slow the absorption of glucose and lipids in the small intestine, thereby reducing postprandial metabolic spikes (Broekaert et al., 2011).