Abstract
The environmental pollution issue related to the widespread use of synthetic surfactants in detergents since 1960s has worried both the scientific community and regulatory agencies, in view of the foaming in rivers and lakes that makes the aquatic environment visually polluted. In this context, biological surfactants have stood out over synthetics due to their biodegradability and biological origin, since they are naturally produced by the microorganisms’ metabolism. However, the production usually requires expensive fermentative media and still demands more efficient methodologies to make the process economically advantageous. To the best of our knowledge, there are no studies in the literature reporting the use of Candida gloebosa, which was collected in Antartica, for producing of biological surfactants. Faced with this, the present study aimed to evaluate some fermentative medium parameters in order to obtain ideal conditions for biosurfactant production using Candida gloebosa. For this purpose, the fermentation time (24, 48, 72 and 96 h), the concentration of residual potato frying oil (40, 60 and 90 g.L-1), the concentration of hydrated magnesium sulfate (MgSO4.7H2O) (0.1, 0.15, 0.2 and 0.3 g.L-1), and cells concentration (1 ± 0.2, 2 ± 0.3, 3 ± 0.2 e 4 ± 0.3 g.L-1) were evaluated. According to the results, all the four parameters investigated revealed similar production yields at their best condition with a biosurfactant production of about 4 g/L when were employed 72 h of fermentation time, 0.2 g.L-1 of MgSO4, 60 g.L-1 of residual potato frying oil and a cell concentration of 3 g.L-1. Finally, the obtained results were comparable to those already reported in the literature for the yeast of the same genus known as Candida lipolytica, which is used for biosurfactant production. These findings can be used as basis for future studies involving the modeling through neural networks, for instance, in order to obtain an optimized condition or even for biosurfactant production in larger scales.
