Cellulase-free xylanases, production

The second area of application involves the use of cellulase-free xylanases for removal of hemicellulose from pulps (10-20) and plant fibres (21). It is essential that these xylanase preparations are free of contaminating cellulase activity or damage to the cellulose fibres and consequently the product quality will result. 

The preparation of xylanases from cloned systems has permitted production of cellulase-free xylanases. The xylanases produced from cloned... 

Sa-Pereira, P., Mesquita, A., Duarte, J. C., Barros, M. R. A., Costa-Ferreira, M. (2002). Rapid production of thermostable cellulase-free xylanase by a strain of Bacillus subtilis and its properties. Enzyme and Microbial Technology, 30, 924-933. 

Xylanolytic enzymes free of cellulases can be applied in the pulp and paper, textile, and food industries and in basic research. However, most microorganisms grown under natural conditions produce both xylanases and cellulases. Strategies to produce xylanolytic systems free of cellulases are elimination of cellulase activity by separation or inhibition, selection and construction of cellulase-negative strains, and finding conditions for separate production of xylanolytic systems by cellulolytic strains. 

SSF is defined as the fermentation process occurring in the absence or near-absence of free water. SSF is known since antiquity but has gained current scientific attention due to several environmental and apparent economic benefits it offers. It presents potential opportunities for developing green processes employing agro-industrial residues. The cost of production of several enzymes when produced in SSF is lower in comparison to that produced in SmF. At industrial scale, SSF is considered for the production of low-value enzymes such as cellulase, xylanase, amylase, etc. SSF cuts down the cost of production by the following factors ... 

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