Ethanol production by the yeast strains Saccharomyces cerevisiae and Wickerhamomyces anomalous was done by simultaneously cultivating the yeasts in the anode and the cathode of an electrochemical cell alternatively on either side of the electrolytic compartments. When Saccharomyces cerevisiae was cultivated on a platinum plate anode and Wickerhamomyces anomalus was cultivated in graphite rod cathode and an external electric potential of 4V was applied to induce the electrochemical redox reaction in the anode and cathode compartment of an electrochemical cell using glucose as a substrate, 27.61±0.35 mg/ml ethanol was produced. However counter combination produced only 24.78±0.45 mg/ml ethanol. Electrochemical oxidation potential inhibited Wickerhamomyces anomalus but showed a reduced effect on Saccharomyces cerevisiae. Graphite rod when modified by the immobilization of neutral red as a mediator of electron transfer showed improvement in ethanol production. The Wickerhamomyces anomalus when cultured with modified graphite rod and Saccharomyces cerevisiae when cultured in the anode 11.67% more than the neutral red non-immobilized combination of Saccharomyces cerevisiae and Wickerhamomyces anomalusand 64.28% more than that of the control maintained without the supply of external voltage.

Key words: Saccharomyces cerevisiae, Wickerhamomyces anomalus, Electrochemical cell, Neutral red, Platinum, Graphite rod

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