The objectives of this work are to optimize critical environmental parameters for effective biodegradation of crude oil by the pre-isolated and identified strain of B. methylotrophicus USTBa and to characterize biosurfactant produced by various techniques including proton nuclear magnetic resonance spectroscopy (1 H NMR), X-ray diffraction (XRD), thermogravimetry (TG), and differential scanning calorimetry (DSC).In addition, the toxicity of biosurfactant is investigated as this is considered as an important criteria for bioreclamation of oil contaminated soils. In this study, crude oil was used as a model contaminant because it is a common environmental pollutant.