Production of biosurfactant from agro-industrial waste by Bacillus safensis J2 and exploring its oil recovery efficiency and role in restoration of diesel contaminated soil

In this study, biosurfactant production by Bacillus safensis J2 in submerged fermentation employing agro-industrial waste (bagasse) as a sole carbon source was examined. Biosurfactant produced was characterized to predict its properties and stability to various environmental stresses. Further, the strain and its extracted biosurfactant was used in oil recovery operation and in restoration of diesel contaminated soil. Findings suggest that bagasse of sugarcane may serve as an efficient substrate for cost-effective production of biosurfactant as 0.92 +/- 0.06 giL of biosurfactant by the strain was produced in 15 g bagasse. Stability studies indicate that properties of the biosurfactant were stable at various temperature and pH and have the efficiency to persist its emulsification activity at varying salt concentration. Oil recovery operation demonstrated that the biosurfactant is effective in recovering up to 46.5 % of the trapped oil from the sand pack column and acute earth worm toxicity test reveal that the soil treatment E5 (100 g soil + 10 g Bagasse + 250 ml distilled H2O + 10 ml diesel oil+ Strain J2+ 25 ml crude Biosurfactant) is effective in restoration and detoxification of diesel contaminated soil. (C) 2019 Elsevier B.V. All rights reserved.