Abstract
The innovative biosurfactants arisen to replace chemical surfactants in bioremediation processes because of their effectiveness as dispersants, greater stability and biodegradability. Currently, the major market for biosurfactant is the petroleum industry, where these compounds can be used in the cleanup of oil spills, the removal of oil waste from storage tanks, enhanced oil recovery and bioremediation of soil and water. In this sense, this study investigated the stability of the biosurfactant produced by Pseudomonas cepacia CCT 6659 growing in culture medium containing 2 % residual canola oil, 3% corn steep liquor and 0.2 % NaNO3 for 60 hours at stirring 250 rpm and 28 °C. In the cell-free metabolic liquid was added a salt of potassium sorbate (0.2 %) to the conservation of their surfactant properties. Heating, pH and salinity conditions were applied to evaluate the best application results of the biosurfactant for 120 days. The biosurfactant was also used in the engine lubricating oil removal impregnated in samples of coral reefs so as to evaluate its potential in removing petroleum compounds. The most significant results found for biosurfactant were surface tension of 25.92 mN/m, engine-oil emulsifying capacity of 99 % and dispersion 53.5 % oil in seawater. Moreover, the biosurfactant removed 84.5 % of the hydrophobic compound of the coral reefs samples. Based on the presented conservation economical method and in the proven resistance to extreme conditions, the biosurfactant demonstrated its potential for applications in the oil industry and in the environmental decontamination processes.
