Investigations on the Reaction Mechanism of Xylanases and Mannanases on Sprucewood Chemical Pulps

Application of xylanase enzyme of Bacillus coagulans as a prebleaching agent on non-woody pulps

“…This has been first demonstrated by Viikari et al [1] in 1986 and it has been reported that the efficiency of hemicellulases varies with hardwood and softwood pulps [2]. Xylanase and mannanase have been used as a prebleaching agent but the efficiency of xylanase was superior in comparison to mannanase alone [3,4]. Realizing the importance of xylanase, major attention has been paid on developing xylanase as a prebleaching agent [5][6][7][8].…”

Enzyme-Aided Bleaching of Kraft Pulps: Fundamental Mechanisms and Practical Applications

“…by EMCC and MCC, the effect of xylanase treatment on bleachability has been reported to be less pronounced than in conventional kraft pulps after ECF bleaching (65,66). Oxygen delignification carried out prior to the actual bleaching sequence has been found to enhance the susceptibility of pulp hemicellulose to enzymatic solubilization (4,65,68). However, when ECF bleaching sequences are used, oxygen delignification has not been found to increase the effect of xylanase treatment on the bleachability of softwood kraft pulps (69,70).…”

Effects of Enzymatic Removal of Xylan and Glucomannan on the Pore Size Distribution of Kraft Fibres

“…The role of fibre porosity in the enzymatic hydrolysis of fibre-bound substrates has been videly studied by solute (Stone et al I969;Grethlein 1985;Wong et al 1988;Allison et al 1995 a, b;Saake et al 1995). However, not many reports of the effects of enzymes on the porosity of fibres have been published.…”

“…The enzymes are generally considered to act in all accessible surfaces of pulp fibres, i.e. on the outer surface of fibres and in the inner fibre wall (Stone et al 1969;Kantelinen et al 1993b;Saake et al 1995). However, the exact location and distribution of the action of enzymes inside the fibre walls during pulp hydrolysis is not well known.…”