Soluble Cello-Oligosaccharides Produced by Carbon-Catalyzed Hydrolysis of Cellulose

Cello-oligosaccharides are biologically important molecules that can elicit a defensive immune response in plants and improve the health of animals. Cellulose, a polymer of glucose linked by β-1,4-glycosidic bonds, is an ideal feedstock for synthesis of cello-oligosaccharides. However, cello-oligosaccharides rapidly degrade under the conditions used for cellulose hydrolysis. Here, cellulose was hydrolyzed over a carbon catalyst in a semi-flow reactor to achieve a high yield of cello-oligosaccharides (72 %). The excellent activity of the oxidized carbon catalyst, the adsorption of cellulose on the catalyst, and the high space velocity of products in the reactor were essential. Moreover, a method for quantification of individual cello-oligosaccharides was developed, which suggested a reduction in the rate of hydrolysis with a reduction in chain length.