ABSTRACT
The main structural carbohydrates of agricultural and food processing waste are cellulose, hemicellulose and starch and other components such lignin, which are converted by supercritical water to value added products and eliminate the problems related to their disposal. This chapter explores that the arabinoxylan oligosaccharides (AXOS) production for prebiotic purposes by biomass waste transformation using hydrothermal treatment (HT) is an efficient way to achieve it. The lignocellulosic biomass is generally composed of 40-45" cellulose, 25-35" hemicellulose and 15-30" lignin. AXOS consist of xylose backbone with arabinose in the side chain substituted at either or 2nd, 3rd, and 5th positions of xylose and most of these oligosaccharides do consist of ester linked phenolic acids such as ferulic, coumaric and caffeic acids. HT liquefaction is performed at medium temperatures and high pressures at which biomass hydrolyses and decomposes to unstable small components, which further re-polymerize and produce highly viscous water-insoluble bio-oil, water soluble substances, char, and light gasses.
