Two 1-L bioreactors with 500 mL working volume were used:
Control (without addition of biosurfactant) and Test (with addition
of biosurfactant). To ensure adequate oxygen supply, compressed
air was injected through a porous diffuser located at the bottom of
bioreactors. Aeration along with magnetic stirring allowed
maintaining the sludge in suspension and the supply of dissolved
oxygen necessary to the process.