Cello-oligosaccharides production from lignocellulosic biomass and their emerging prebiotic applications

Cello-oligosaccharides (COS) are linear oligosaccharides composed of β-1,4-linked glucopyranose units. They comprise a group of important new oligosaccharides of significant interest and potential applications in the pharmaceutical, food, chemical, and feed industries, currently emerging as potential prebiotic compounds. COS from lignocellulosic biomass, specifically the agro-industrial residues and by-products of the forestry industry, constitute a new attractive process that imposes the sustainable use of biomass resources. Two main strategies have been used for the production of COS: acid-based and enzyme-based cellulose hydrolysis. The latter has been considered more attractive due to the use of milder reaction conditions and less production of monomers. This review summarizes that although COS is emerging as a potential prebiotic with also other potential applications, there is a lack of information regarding the large-scale production, which could be associated with the recalcitrant nature of cellulose compared to other polysaccharides, which hinders the hydrolysis of its dense network.