Activation of Ethanol Production by Combination of Recombinant Ralstonia eutropha and Electrochemical Reducing Power

Bo Young Jeon, Jun Yeong Yi, Il Lae Jung, Doo Hyun Park

Department of Biological Engineering, Seokyeong University, Seoul, South Korea.
Department of Radiation Biology, Environmental Radiation Research Group, Korea Atomic Energy Research Institute, Daejeon, South Korea.

DOI: 10.4236/aim.2013.31006                

Abstract

Ralstonia eutropha was genetically modified to induce ethanol production from glucose. An electrochemical bioreactor was prepared to generate electrochemical reducing power coupled to regeneration of NADH. Growing cells of recombinant R. eutropha produced about 29 mM of ethanol in conventional conditions and 56 mM of ethanol in electrochemically reduced conditions from 100 mM glucose. Grown cells of the recombinant produced about 52 mM of ethanol in conventional conditions and 142 mM of ethanol in electrochemically reduced condition from 100 mM glucose. These results are a clue that electrochemical reducing power can induce the recombinant R. eutropha to produce more ethanol coupled to increase of NADH/NAD⁺ ratio.

Keywords

Ralstonia eutropha; Electrochemical Reducing Power; Genetic Recombination; Pyruvate Decarboxylase; Alcohol Dehydrogenase

Conflicts of Interest

The authors declare no conflicts of interest.

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