Xylooligosaccharides from Biomass Lignocellulose: Properties, Sources and Production Methods

Abstract

Xylooligosaccharides are functional food supplements that refer to indigestible oligosaccharides consisting of D-xylose molecules linked by β-1,4-glycosidic bonds. Xylooligosaccharides in the human body perform the functions of prebiotics; they have antioxidant, immunomodulatory and antitumor effects. In industry, xylooligosaccharides are obtained from lignocellulosic biomass by hydrolysis of the xylan contained therein. Chemical hydrolysis is carried out with acid or alkali solutions and is associated with negative environmental consequences. Autohydrolysis refers to methods of physical impact on lignocellulosic raw materials, in which, under the action of high pressure and temperature, steam cracking of raw materials and separation of carbohydrates into fractions occur. Enzymatic hydrolysis of xylan provides the purest products and allows you to control the functional orientation of the resulting xylooligosaccharides. Hydrolysis of xylan to obtain xylooligosaccharides is carried out by microbial xylanases and β-xylosidases produced by bacteria, molds, and actinomycetes. Xylanase producers are ubiquitous in lignocellulosic raw materials and isolated from soil, corn cobs, wheat husks, rice and wheat straw, sugarcane bagasse, oil palm waste, wood chips, sugar bagasse, forest litter, and eucalyptus leaves.