Ominyi Matthias C.
In the present study, optimization of medium composition and culture conditions for α-amylase and glucoamylase production by three fungal strains isolated from Abakaliki metropolis were investigated. The fungal isolates include Aspergillus species (AS-2a), Mucor species (MS-3) and Rhizopus species (RS-6b). The parameters such as optimal incubation period, pH, temperature, carbon sources and starch concentrations were considered in the study. Maximum enzyme activities of the isolates were attained at 120 hours incubation period. The isolates had their optimal amylase enzymes production at pH 4.0. The optimum temperature for α-amylase enzyme activities was 45°C while the maximum activities of glucoamylase were obtained at 30°C. Of the carbon sources tested, sweet potato starch gave the highest amylase activities. The optima starch concentrations for α-amylase and glucoamylase production by the isolates were 50 g/l and 80g/l, respectively. The enzymatic activities were measured quantitatively using potassium-iodide spectrophotometric method and glucose-oxidase/peroxidase method for α-amylase and glucoamylase respectively.
