Hydrolysis of water-soluble cellulose acetate prepared from waste newspapers by immobilized cellulase

For the purpose of saccharifying waste newspapers by immobilized enzyme, the waste newspapers were delignified by cooking them with acetic acid or oxygen-alkali and then partially acetylated in non-aqueous solvent. This treatment converted almost completely the polysaccharide fraction of the the delignified waste newspapers into water-soluble material. This substrate was hydrolyzed by the dual reaction system with the immobilized enzyme prepared from commercial cellulase. The couplings of cellulase on two carriers, DEAE-Toyopearl and Chitopearl were investigated. The recoveries of the maximum CMCase activity by each carrier were 54 and 42%, respectively. The immobilization caused elevation of the optimum temperature and spread of the pH range for enzyme reaction. The maximum degree of hydrolysis (73%) based on the water-soluble substrate from the waste newspapers was similar to that in the case of using cellulose powder as a starting material. The primary hydrolyzate contained much cello-oligosaccharide (G(2)-G(5)) with glucose and a little hemicellulose sugar, but, after deacetylation and secondary hydrolysis, glucose comprised 73% of the total hydrolyzate.