Production and properties of fungal cellulase from native isolates using orange bagasse as carbon source

Abstract

Orange bagasse was employed as the sole carbon source for production of cellulase having adapted the organisms on cellulose and on orange bagasse. The extracellular cellulase produced by Aspergillus niger and Rhizopus species were partially purified by ammonium sulphate precipitation in a single step and dialyzed. Cellulase activity of partially purified cellulase from Aspergillus niger and Rhizopus species were determined. Cellulase from both fungi had optimum temperature at 45°C but different pH optima of pH 7 and 6.5 respectively. Thermo stability study of the partially purified cellulases carried out over a temperature range of 35°C -70°C show that the enzymes lost stability with increasing temperature. Carboxymethylcellulase (CMCase) and Filter paper unit (FPU) activities of the partially purified cellulase show a higher specific activity for cellulase from Aspergillus niger than that from Rhizopus species.

Key words: Cellulase, CMCase, Aspergillus niger, Orange bagasse