Microbial metabolism and prebiotic potency of arabinoxylan oligosaccharides in the human intestine

Arabinoxylans (AX) are the main non-starch polysaccharides found in many cereal grains and are part of dietary fibre. They consist of β-(1,4)-linked d-xylopyranosyl residues to which arabinofuranosyl moieties are attached. They are degraded in the colon by specific intestinal bacteria possessing AX-degrading enzymes. Although some health effects of AX are documented, the effects of their hydrolysis products, the arabinoxylan oligosaccharides (AXOS), are less studied. Many oligosaccharides exert prebiotic activities and there are indications that xylo-oligosaccharides consisting of β-(1,4)-linked d-xylopyranosyl residues show strong bifidogenic effects. Therefore, the in-depth study of the prebiotic potential of AXOS and the intestinal microbiota involved in their transformation processes is warranted.