Enzymatic degradation of cellulose

Influence of Cellulose Physical Structure on Thermohydrolytic, Hydrolytic, and Enzymatic Degradation of Cellulose... 

Table VIII. Enzymatic Degradation of Cellulose Powders of Different Origin and Particle Size (Cellulose T, 1% Substrate 68 hr 40°C)...

Table X. Influence of NH3 Pretreatment and of Mercerization on Enzymatic Degradation of Cellulose Powders...

The Mode of Enzymatic Degradation of Cellulose Based on the Properties of Cellulase Components... 

At present cellobiose is not a practical substrate for amylose production, but the enzymatic degradation of cellulose is extensively studiedand the conversion of cellobiose into amylose by the CBP-GP system should be the important way to convert cellulosic biomass into value-added materials and products. 

The use of membrane separation as a component of continuous fermentation systems is growing in interest. In this case it is possible to increase the productivity of product-inhibited fermentation, for example, by the continuous removal of the low molecular weight products. The enzymatic degradation of cellulose to alcohol, where the microorganisms used are inhibited at an alcohol concentration higher than 12%, might be improved by the use of this concept. 

Size and Diffusibility of Cellulolytic Enzymes in Relation to the Capillary Structure of Cellulose. As discussed earlier, enzymatic degradation of cellulose requires that the cellulolytic and other extracellular enzymes of the organisms diffuse from the organism producing them to accessible surfaces on or in the walls of the fiber. This accessible surface is defined by the size, shape, and surface properties of the microscopic and submicroscopic capillaries within the fiber in relation to the size, shape, and diffusibility of the enzyme molecules themselves. The influence of these relationships on the susceptibility and resistance of cellulose to enzymatic hydrolysis has not been verified experimentally in natural fibers but the validity of the concepts that follow is demonstrated by the work of Stone, Scallan, Donefer, and Ahlgren (69). 

Most of what is known about the enzymatic degradation of cellulose largely ignores the organism-substrate-relationship that is an integral part of the process. In reality our studies are confined to isolated enzymes and modified substrates. But there is no true alternative to using modihed substrates. Thus, any mechanism of cellulose degradation... 

In a very creative fashion, Hu and Catchmark [140] developed bioabsorbable cellulose nanocomposites by integration of cellulases into BC membranes (Figure 2.17). Considering the harmless effect of the main product of the enzymatic degradation of cellulose, glucose, these composites may be perfect for specific wound care and tissue engineering applications where the bioabsorbable character is crucial. 

Itavaara, M., Siika-Aho, M. Viikari, L. (1999). Enzymatic degradation of cellulose based materials. Journal of Environmental Polymer Degradation, 7, 67-73. 

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