Direct current stimulation of Thiobacillus ferrooxidans bacterial metabolism in a bioelectrical reactor without cation-specific membrane.

A bioelectrical reactor without cation-specific membrane was designed to test effects of direct electrical current on growth of Thiobacillus ferrooxidans bacterium. The results indicated that the cell significantly enhanced the growth of T. ferrooxidans. At a current of 30 mA, the maximum cells density reached 1.39 x 10(9)cells/mL within 84 h, which was 10 times faster than under a conventional cultivation method, in which electrical current is not used. A lag phase during the growth of T. ferrooxidans was observed when direct electrical current was applied, and the lag phase became longer under higher current intensity.