Produção de biossurfactantes a partir de substratos de baixo custo

Abstract

Due to the range of uses in the oil industry, hygiene products and cosmetics, mining, agriculture, pharmaceutical, paper and pulp, textiles and ceramics, the biosurfactants have been widely studied, motivated by the strong tendency in replace synthetic to biological products in industrial and environmental applications. The fact of the microorganisms withstand the most adverse environmental conditions from the mild and are found in various types of substrates, become producers of a range of biosurfactants with diverse applicability, potential toxicity and biodegradability smaller than the synthetic surfactants. This present study aimed to isolate, select and characterize bacteria, molds and yeasts from agroindustrial wastes as vinasse, manipueira and residual oil of frying. The micro-organisms isolated, were studied the potential for producing molecules of biosurfactants, test for biodegradability in concentrations of 0.2, 0.6 and 1% of oil in the presence of redox indicator 2,6-dichlorophenol indophenol (DCPIP). After selection, it was evaluated the capacity to produce biosurfactants and oil emulsion formation when compared to a synthetic surfactant such as sodium lauryl sulfate (SLS®), measuring the surface tension and submission of these molecules in situ bioremediation of petroleum. Of the initial results, 50 micro-organisms were isolated, of which 32 maintained cell viability. Of these, 17 microorganisms were from manipueira, 5 of vinasse and 10 of the residual oil for frying. To test for biodegradability, it was found that 35% of microorganisms from manipueira degraded percentages of 0.2 to 0.6% of oil and 20% of microorganisms of vinasse and 30% of these from oil for frying also degraded the same concentrations of oil supply, degraded some even up to 1% of oil after 4 hours of evaluation. The fermentation process when the residual oil for frying and manipueira as substrates had higher rates of reductions in surface tension of water and percentage of oil bioremediation in beach sand contaminated with , about 81%, when compared to the other sources of carbon as vinasse and glucose