Production of glucose oxidase by fermentation from Aspergillus niger

Studies were conducted on optimum production of glucose oxidase (β-D-glucose: oxygen, 1-oxidoreductase, EC.1.1.3.4) using the mycelium of Aspergillus niger (RRL-150) with the objective of finding most appropriate conditions viz., medium, temperature, stirrer speed, cultivation time and buffering agents for optimum production of glucose oxidase. Amongst the various substrates tested (glucose, sucrose and fructose), glucose showed maximum activity of glucose oxidase (37.1 U ml⁻¹) at 30°C and 800 rpm at 18h of fermentation. Calcium carbonate (3.5%) was extremely important in maintaining the medium at pH high enough so that the enzyme was not inactivated.