Conversion of Glucose into Gluconic Acid by Means of Immobilized Glucose Oxidase

Abstract The properties of a glucose oxidase from Aspergillus niger var., immobilized by different methods were studied in a batch process. Dependencies between formation of gluconic acid and concentration of enzyme and glucose, supply with oxygen, pH‐value and temperature were determined and the optimal parameters of reaction fixed. In this connexion consideration of the oxygen demand of the system was of special importance. Different “oxygen carriers” (pure oxygen, air, hydrogen peroxide) were used and their influences investigated not only on glucose oxidase but also on catalase, which is a conclusive fact in the reaction process. This led to very informative experiences on stability, re‐usability and productivity of the carrier bound enzyme system. The results obtained should be applied to develop a continuous process for gluconic acid production and an enzyme preparation adapted to this process.