Glucose oxidase catalysed oxidation of glucose in a dialysis membrane electrochemical reactor (D-MER)

The purpose of this work was to evaluate the effectiveness of a new Membrane Electrochemical Reactor (MER) for the production of gluconic acid by glucose oxidase (GOD) catalysed glucose oxidation. The GOD was confined against the electrode surface with a dialysis membrane. The role of the electrochemical step was to eliminate by oxidation the hydrogen peroxide that appeared as a by-product of the reaction and strongly inhibited and/or inactivated GOD. The dialysis MER gave a transformation ratio of 30% with an initial glucose concentration of around 300 mM. This result is significantly better than the maximum of 10% obtained when hydrogen peroxide was eliminated by addition of a large excess of catalase in solution, as is generally done. The D-MER also revealed unexpected properties of the enzyme kinetics, such as an oscillatory behaviour, which were discussed.