The effects and benefits of arabinoxylans on human gut microbiota : a narrative review

Prebiotics are a class of functional foods which target beneficial microbial species of the gut to benefit host health. They consist of dietary fibres which, after ingestion, are degraded and fermented by microorganisms in the colon. Arabinoxylan (AX) is an important member of the prebiotic family. This non-digestible fibre is commonly found in cereal grains such as wheat and rice. Human in vivo studies have demonstrated that consumption of various species of AXs has profound effects on gut microorganisms. AX exists in different structures across cereal types. Structural differences of AXs impact their cleavage, degradation, and fermentation by gut microbiota. However, this structural diversity also makes it difficult to compare and contrast studies of different AXs. Nevertheless, common bacterial targets of prebiotics across all AX structures include Bifidobacterium spp. and Lactobacillus spp., which are both beneficial to human health. Existing research on AXs has primarily focused on wheat derived AX. As the structure of rice AXs varies significantly from that of wheat AXs, more research is needed on the effects of rice AXs on gut microbiota. This narrative review synthesises the current understandings of how prebiotic AX affects gut microbiota and its implications for human health.