Induction of Cellulase Biosynthesis by Cellobiose Octaacetate in <i>Aspergillus humicola</i>
Keywords:Aspergillus humicola, Carboxymethylcellulase (CMCase), Carboxymethylcellulose (CMC), Cellobiose octaacetate (COA)
Aspergillus humicola, one of the major cellulase-producing fungi, was used in this study for carboxymethylcellulase (CMCase) production using Winstead's basal broth supplanted with cellobiose octaacetate (COA), a synthetic carbon source. Under all conditions, the enzyme biosynthesis was remarkably increased when the inducer COA was added to the production medium containing carboxymethylcellulose (CMC). Maximum enzyme production (1.62 U/ml) was achieved in COA-containing at 37°C. The enzyme production was highest at initial pH 5.5 and after 7 days incubation. The enzyme exhibited maximum activity at 40°C with a reaction pH 5.5. CMCase activity was inhibited by its own substrate CMC at concentration higher than 1.0%. The study clearly demonstrated that COA is a good inducer for extracellular CMCase production by the fungus.
Keywords: Aspergillus humicola, Carboxymethylcellulase (CMCase), Carboxymethylcellulose (CMC), Cellobiose octaacetate (COA)
Bangladesh J Microbiol, Volume 23, Number 2, December 2006, pp 174-176