Biosurfactant Production by Fermentation
Abstract
The production of biosurfactants is a more environmentally conscious and sustainable approach compared to petrochemical-derived surfactants. One of the main disadvantages preventing commercialization of biosurfactants is their high production costs. To improve process efficiency by increasing productivity, process modifications with a nitrogen enriched media and operating temperatures were explored. Fermentation conditions of 25°C, 800 rpm, pH of 3.5, and an aeration of 5.6 L/min, were used to evaluate the consistency of yields and productivity. At 25°C, the nitrogen rich fermentation encountered challenges maintaining dissolved oxygen (DO) >30%. This was overcome by operating at a lower temperature of 20°C during the growth phase of the cells. Nitrogen rich conditions of 20°C<24h, 25°C>24h yielded a biosurfactant productivity of 1.53 g/ L h which was 194% higher and 3 times more productive than baseline conditions. Further optimization of nitrogen rich media is suggested to balance cellular growth and product formation.