4. ConclusionThe biosurfactant produced by B. subtilis ICA56 is an effectivetensoative and emulsifier. Furthermore, the crude biosurfactanthas potential to be used in bioremediation, since it is capableof efficiently remove hydrocarbons and heavy metals from con-taminated systems in a broad range of pH, temperature and NaClconcentration, with the advantage of being nontoxic. Some agro-industrial wastes such sunflower oil and glycerol can be used as lowcost substrates for the biosurfactant production, rendering around1.000 mg L−1of crude biosurfactant.AcknowledgmentThe authors are grateful for the financial support provided bythe Brazilian research agencies ANP, CNPq and CAPES