The effect of changes in manganese concentrations on cellulase yield from bagasse fermented with mutagenised strain of Aspergillus niger AH3

The effect of changes in manganese ion concentrations on cellulase yield from bagasse fermented with a hydroxylamine derived mutant of Aspergillus niger were investigated in a batch culture shake flask fermentations. Three different concentrations were studied using the Mandel-Weber basal medium adjusted to pH 4.8. Enzyme production profile was monitored over a seven day period. Bagasse was found to be a good carbon source and it induced active cellulase production. Cellulase activities were recorded as 0.07256 IU/ml/min, 0.04820 IU/ml/min and 0.04258 IU/ml/min for 0.16 g/L, 0.59 g/L and 0.67 g/L of manganese respectively. Day 4 appears to be best for optimum production of the enzyme at the concentrations studied. Increasing concentrations of manganese ion which is a requirement for pectolytic enzyme and citric acid accumulation in Aspergillus niger does not promote excellent cellulase production from bagasse. Keywords : cellulase, manganese, bagasse, pectolyic, hydroxylamine, mutant, Aspergillus niger Int. J. Biol. Chem. Sci. Vol. 2 (3) 2008: pp. 368-372