Biosurfactant production by Aureobasidium pullulans in stirred tank bioreactor: New approach to understand the influence of important variables in the process.

Surfactants are amphiphilic molecules with large industrial applications produced currently by chemical routes mainly derived from oil industry. However, biotechnological process, aimed to develop new sustainable process configurations by using favorable microorganisms, already requires investigations in more details. Thus, we present a novel approach for biosurfactant production using the promising yeast Aureobasidium pullulans LB 83, in stirred tank reactor. A central composite face-centered design was carried out to evaluate the effect of the aeration rate (0.1-1.1min) and sucrose concentration (20-80g.L) in the biosurfactant maximum tensoactivity and productivity. Statistical analysis showed that the use of variables at high levels enhanced tensoactivity, showing 8.05cm in the oil spread test and productivity of 0.0838cm.h. Also, unprecedented investigation of aeration rate and sucrose concentration relevance in biosurfactant production by A. pullulans in stirred tank reactor was detailed, demonstrating the importance to establish adequate conditions in bioreactors, aimed to scale-up process.