Extraction and Partial Purification of Glucoamylase from Rhizopus oryzae by Solid State Fermentation using Agro-Industrial Residues

Background: Filamentous fungi are used to produce many industrial enzymes because these fungi have a great ability to produce such enzymes, especially when using solid substrates that are usually low in cost. The widespread use of this enzyme has made it very important to work on improving its production to achieve the maximum possible benefit.Methods: Five fungal isolates were obtained from soil and decaying fruits and vegetables. All isolates were identified as Rhizopus spp. and cultured on Potato Dextrose Agar (PDA) plates escorted by starch 1%. The appearance of clearance zones around the fungal colonies represents the ability of fungi to produce Glucoamylase. Different solid substrates, nitrogen sources, and temperatures were used to improve enzyme production.Results: Wheat bran gave the highest enzyme production with specific activity 6.25 U/mg, and yeast extract was the potent inducer for enzyme production with specific activity 9.28 U/mg. The optimal temperature for enzyme production was 30°C with specific activity10.27U/mg. Maximum specific activity 18.40U/mg was recorded at 55% saturation with ammonium sulfate precipitation. The result showed increased specific activity 24.84U/mg with dialysis. Partial purification of the enzyme revealed that pH5 was optimum for enzyme-specific activity 9.2U/ml; higher enzyme-specific activity was found with MnSO4 (11.83U/ml) as the best enzyme inducer.Conclusion: This investigation attempted to examine R. oryzae as an effective maker of GA. Innovative work into the nearby creation of GA for industrial use utilizing local resources has demonstrated financial effectiveness. It requires improvement into consistency as needed by worldwide associations dealing with industrial enzymes. Keywords: Glucoamylase; Production; Partial purification; Rhizopus oryzae; Solid state fermentation