Optimization of glucose oxidase production by Aspergillus niger

Abstract

The glucose oxidase was produced by fermentation using Aspergillus niger isolated from potato as producer organism and glucose as the carbon source (substrate). Maximum production of the enzyme (1.59 ìmoleHQMin-1ml-1) was achieved at 10% glucose concentration after 48 h of submerged fermentation. The pH for the optimal production of enzyme was found to be 5.5 (enzyme activity 1.56 ìmoleHQMin-1ml-1). Addition of urea (0.2%) and KH2PO4 (0.4%) into the fermentation medium increases enzyme activity (2.01 and 2.96 ìmoleHQMin-1ml-1, respectively) while MgSO4·7H2O was found to inhibit GOX production by A. niger.

Key words: Glucose oxidase, Aspergillus niger, glucose oxidase.