From agriculture to industry:

Lignocellulosic biomass is a renewable source of raw§material for the production of a wide variety of §compounds. The thesis deals with the production of §xylo-oligosaccharides from agricultural residues §(typical from the Mediterranean region of Spain) §with potential applications in the food and §pharmaceutical fields. The xylo-oligosaccharides §were produced by autohydrolysis reaction varying the §temperature and reaction time. All the xylo-§oligosaccharides obtained showed structural features§of a partially O-acetylated 4-O-methylglucuronoxylan§with different degrees of substitution depending on §the raw material used. Several purification methods§were tested for the removal of impurities and/or§separation in different molecular weight fractions,§like precipitation, ultrafiltration using polymeric §membranes and adsorption of impurities onto §activated carbons. The antioxidant activity and the §immunomodulatory activity of xylo-oligosaccharides §were also tested. It was found that all of them have §a strong antioxidant activity compared with that of §natural products, making them potential candidates §for their use as food additives.