Xylanases biobleaching

Cellobiose induces xylanase s3mthesis in some microorganisms [24], but sometimes, this enzyme is associated with cellulases. The crude enzymatic extract produced by B. circulans D1 on cellobiose is free of cellulases. This is important data that confirm the enzyme potential for application in biobleaching processes [6]. 

Bocchini, D. A., Damiano, V. B., Gomes, E., Da Silva, R. (2003). Effect of Bacillus circulans D1 thermostable xylanase on biobleaching of eucalyptus Kraft pulp. Applied Biochemistry. Biotechrmlogy, 70(5(1-3), 393 02. 

Dhillon, A., Gupta, J. K., Jauhari, B. M., Khanna, S. (2000). A cellulase-poor, thermostable, alkalilolerant xylanase produced by Bacillus circulans AB 16 grown on rice straw and its application in biobleaching of eucalyptus pulp. Bioresource Technology, 73, 273-277. 

Biobleaching Efficiency of Aspergillus oryzae Xylanases Produced by Solid Substrate Fermentation... 

Binding of xylanase components shake flasks by SF, has been carried out on sulfite pulps (8). Although xylanases from A. oryzae has been produced exclusively in SF (4,8,14,31), a SSF alternative has been demonstrated most recently (IS). However, no reports are found in flie iit ture on the use of xylanase enzymes produced by this fringus in SSF for biobleaching of cellulose pulps. 

USDl/t pulp (Fig. 2a). The biobleaching effect could be translated into 28% savings of chlorine dioxide in comparison to the 24% reductions induced by the xylanase before media optimization (data not shown). Thus, at equal enzyme costs, the SSF xylanase produced under optimized conditions outperformed the commercial enzyme by 60%. At equal enzyme charges (S lU/g pulp), the A. oryzae enqone was 17% more efficient dian the commercial product (Fig. 2b). 

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