Broad prebiotic potential of non-starch polysaccharides from oats (Avena sativa L.): an in vitro study

Prebiotics inducing the growth or activity of beneficial intestinal bacteria – probiotics producing short-chain fatty acids (SCFA) have lately received wide recognition for their beneficial influence on host intestinal microbiota and metabolic health. Some non-starch polysaccharides (NSP) are defined as prebiotics and oats being one of richest sources of NSP in grains are considered as potentially having prebiotic effect. However, information on fermentation of specific NSP of oats is limited. Moreover, bacterial cross-feeding interactions in which fermentation of prebiotics is involved is poorly characterized. Here, we report the exploration of new candidates for the syntrophic bacterial interactions and fermentability of oat non-starch polysaccharides (NSP). The results obtained by differentiating composition, viscosity and concentration of oats NSP in fermentation medium showed that Bacillus licheniformis pre-digests oat NSP, degrades high viscosity of oat β-glucan and makes hemicellulose easier to access for other bacteria. Because of fermentation, B. licheniformis produces lactic and succinic acids, which further can be used by other bacteria for cross-feeding and SCFA production.