The main object of this work is to present a “proof of concept” test of a method to produce Polyhydroxybutyrate (PHB) in the cathode of the Microbial Electrolysis Cell (MEC) utilizing directly the H2 gas via the electrons generated at the anode in the oxidation of an organic substance. A batch test in a rectangular microbial electrolysis cell has been performed at room temperature (20÷22 °C). In the anode compartment a solution of Volatile Fatty Acids was used as organic electrons donor while the cathode was filled with a mineral solution to assure the electrical continuity. A. eutrophus is able to growth and to produce PHB in autotrophic conditions on a gaseous substrate of H2, O2, CO2 using organic contaminated waste­water as electron donor. This seems a good option compared to an expensive substrate as glucose, even if a low PHB productivity was reached: about 2% after 3 days of batch test.

Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 2327-2331