In this work, biosurfactant production by Wickerhamomyces anomalus CCMA 0358 was increased through the development of an optimized culture medium using response surface methodology. The optimized culture medium contained yeast extract (4.64 g/L), ammonium sulfate (4.22 g/L), glucose (1.39 a) and olive oil (10 g/L). Biosurfactant production using this medium was validated both in flasks and bioreactor, and the surface tension was reduced from 49.0.mN/m up to 31.4 mN/m and 293 mN/m, respectively. In both cases, the highest biosurfactant production was achieved after 24 h of growth. W. anomalus CCMA 0358 demonstrated to be a fast biosurfactant producer (24 h) as compared to other yeast strains previously reported (144-240h). The produced biosurfactant remained stable at high temperature (121 degrees C), NaCl concentrations as high as 3008/L, and pH values between 6 and 12. The crude biosurfactant allowed the recovery of 20% of crude oil from contaminated sand, being a promising candidate for application in bioremediation or in the petroleum industry. (C) 2017 Elsevier B.V. All rights reserved.