PURPOSE:To obtain a high activity of a microorganism (group) and wide optimum cultivation conditions, by carrying out fermentation while applying a high-voltage static potential to a culture medium containing water. CONSTITUTION:Water is charged with high-voltage static potential and used for preparing a culture medium containing a fermentation raw material, which is filled in a fermenter provided with electrodes connected to a high-voltage static potential generator through electrode cords. The fermenter is insulated, and a given microorganism (group) or mold starter is inoculated into the culture medium and multiplied while applying >=500V high-voltage static potential thereto to carry out fermentation. The fermentation rate is high, and energy consumption is small.
