Application of Electro-energizing Method tol-Glutamic Acid Fermentation

Abstract
An electro-energizing fermentation (E-E F) method has been developed. In this method, a direct electrical current is applied to a microbial culture to accelerate the reductive metabolism of microorganisms or to impart profitable effects to microbial cells. This E-E F method was applied to l-glutamic acid fermentation by Brevibacterium flavum No. 2247. When glucose was used as a substrate, the addition of 0.01 mm neutral red (NR), redox dye (electron carrier), to the fermentation broth at the beginning of cultivation was effective for l-glutamate (l-Glu) production. A direct current of 200~300 μA/cm2 at 1.5 V was applied through out the cultivation of this bacterium. This resulted in about a 10% increase in yield of l-Glu.