Electrochemical measurement of trace concentrations of biological hydrogen produced by Enterobacteriaceae

Accurate measurements of the hydrogen gas produced by Escherichia coli and Hafnia alvei pure cultures during glucose metabolism were performed under different growth conditions: stagnant, with magnetic stirring or with vibrational shaking. These measurements were carried out using an electrochemical hydrogen sensor based on a platinum-coated solid polymer electrolyte membrane (Pt-SPE). The results obtained were dependent on the hydrodynamic conditions of the growth, with greater hydrogen production being associated with the stagnant conditions. These measurements will eventually enable us to elucidate whether the pathway used for glucose metabolism is either strictly or mainly anaerobic and to modify experimental conditions so as to influence the reaction.