M. Costaferreira et al., XYLANOLYTIC ENZYME-PRODUCTION BY AN ASPERGILLUS-NIGER ISOLATE, Applied biochemistry and biotechnology, 44(3), 1994, pp. 231-242
Production of xylanolytic enzymes by an Aspergillus niger CCMI 850 iso
late was investigated in batch cultures. The effect of the composition
of a fermentation medium that did not include chemical inducers, on b
eta-xylanase, beta-xylosidase, alpha-L-arabinofuranosidase, and total
cellulase activity was studied. With 4% xylan as the carbon source, ab
out 65 U/mL of beta-xylanase was obtained, whereas the total cellulase
activity was undetectable, under the specified conditions. This beta-
xylanase activity represents the highest reported for a wild-type stra
in of A. niger. The effect of pH and temperature on the activity of be
ta-xylanase was studied. Partial characterization of the beta-xylanase
showed that with insoluble birchwood as substrate the K-m and Vmax we
re 0.3 mM and 19 mu mol/min, respectively. Aspects of using the crude
beta-xylanase preparation for applications in the pulp and paper indus
try were discussed.