In vitro assessment of prebiotic properties of xylooligosaccharides produced by Bacillus subtilis 3610

Xylooligosaccharides (XOS) are emergent prebiotics exhibiting high potential as food ingredients. In this work, in vitro studies were performed using human fecal inocula from two healthy donors (D 1 and D2) to evaluate the prebiotic effect of commercial lactulose and XOS produced in a single-step by recombinant Bacillus subtilis 3610. The fermentation of lactulose led to the highest production of lactate (Dl: 33.7 0.5 mM; D2:19.7 0.3 mM) and acetate (Dl: 77.5 0.6 mM; D2: 81.0 0.7 mM), while XOS led to the highest production of butyrate (Dl: 9.0 0.6 mM; D2: 10.5 0.8 mM) and CO2 (Dl: 8.92 0.02 mM; D2: 11.4 0.3 mM). Microbiota analysis showed a significant decrease in the relative abundance of Proteobacteria for both substrates and an increase in Bifidobacterium and Lactobacillus for lactulose, and Bacteroides for XOS.