Biotechnology approach for conversion of agro-industrial wastes into emerging source of xylooligosaccharides

Xylooligosaccharides (XOS) are xylose oligomers produced from agro-industrial wastes through xylanases action. They show prebiotic properties that add value to commercial products, such as beverages and foods. Soy husk, rice bran, and corn cob were pretreated and hydrolyzed by recombinant xylanases with high catalytic activity, and the XOS were quantified. Finally, XOS were evaluated for their ability to selectively stimulate the growth of the probiotic Lactobacillus acidophilus. Three recombinant xylanases were produced, with emphasis on SM2 xylanase, which showed activity of 21,853.10 U/mL. Hydrolysis of corn cob generated the higher XOS concentrations, while rice bran saccharification led to high XOS diversity. Soybean husks showed a lower yield concerning XOS release, but it stood out in generating xylohexose. The in vitro prebiotic assay showed that L. acidophilus was able to grow and to ferment the produced XOS, generating mainly propionic acid, which was not observed for the pathogens.