Production of Biosurfactants for Application in the Removal of Hydrophobic Contaminants Originateci by the Petroleum lndustry

Abstract

This work describes the application of microbial surfactants in the removal of petroleum and a derivative from marine environment. Two biosurfactants were produced by the yeasts Candida sphaerica and C. lipolytica cultivated in industriai residues as substrates during 144 h and 72 h, respectively. The surface tensions of the biomolecules were measured (25 mN/m), the production yields were calculated (8-9 g/L) and the Criticai Micelle Concentrations (CMC) determined (0.03 %). Both biosurfactants were applied in samples of sea water and coral reefs artificially contaminateci with petroleum and motor oil. The results showed a dispersant action of the biosurfactant from C. sphaerica while the biosurfactant from C. lipolytica showed a great oil emulsification capacity. Petroleum and motor oil percentages removal of 100 % were obtained. The possibility of application of these biosurfactants in the remediation of environments contaminateci by hydrophobic hydrocarbons motivates the development of this alternative technology.