Abstract: | The growth of microorganisms in fermentations where oil had been maintained as the continuous phase was examined to determine whether advantage could be gained from the increased solubility of oxygen in hydrocarbon. Although cell concentrations were highest in the aqueous phase of oil-continuous systems, due to the large oil fraction, productivities achieved per unit fermenter volume were generally equivalent to those obtained from water-continuous systems. With the oil-continuous emulsions, the power requirement for aeration and mixing was less, and phase reversal resulted in a threefold concentration of cells in the aqueous medium, thereby facilitating their recovery. |