Propagation of Aspergillus niger in stirred fermentor for the production of glucose oxidase

The present research work was planned for enhanced glucose oxidase production in Aspergillus niger by optimizing the growth conditions in a stirred fermentor. The results revealed that medium M2 containing (g/L) glucose 80.0, peptone 3.0, (NH4)2HPO4 0.388, KH₂PO₄ 0.188 and MgSO₄.7H₂O 0.156 was the best among four tested media. Glucose (8%) was the best carbon source for the maximum yield of glucose oxidase (118 U/g cell mass) followed by sucrose (103 U/g cell mass) and fructose (99 U/g cell mass). (NH₄)₂HPO₄ followed by peptone were the best nitrogen sources for the growth of A. niger and production of glucose oxidase. The maximum activity (118 U/g) of glucose oxidase was produced after 72 hours of fermentation at pH 5.0, temperature 30°C, agitation 200 rpm and aeration of 1 vvm.