Enhancement of acetic acid production in a high cell-density culture of Acetobacter aceti

Abstract

The rate of production of acetic acid was greatly enhanced by a high cell-density culture of Acetobacter aceti. Acetobacter aceti cells were recycled through a hollow fiber filter module, and the high acetic acid production rate of 120 mg/ l/h (at an exit acetic acid concentration of 40 g/ l) at the dilution rate of 4.0 h −1 was obtained. High viable cell concentrations were maintained by using medium rich in yeast extract and controlling the DO concentration at an optimum level. Viable cell concentrations increased with increasing added amounts of yeast extract in the medium as long as the acetic acid concentration was not higher than 40 g/ l. When DO and yeast extract were not depleted from the culture, the correlation between the acetic acid production rate ( PD) and the dilution rate ( D) was given as, PD = 7.1 + 34.5 D (0.3 ≤ D ≤ 3)