Results in Chemistry (Dec 2023)
Biossurfactant production by isolated bacteria from petroleum industry’s effluent targeting bioremediation
Abstract
In this study, bacterial strains from the Bacillus genus were isolated from residual effluents from treatment unit of a Petroleum Factory to produce a biosurfactant, aiming the bioremediation of oil-contaminated soils. Five strains were selected to perform fermentation tests. Results showed that the strain LUB P1 presented a lipopeptide with excellent properties, which reduced the surface tension to rates below 30 mN/m. The bacteria were genetically identified as a species belonging to the Bacillus subtilis. Characterization of the biosurfactant confirmed that the main component is surfactin, with a critical micellar concentration (CMC) value of 15 mg.L−1 and high stability to temperature, salinity, and pH variations. In addition, showed low toxicity compared to synthetic surfactants. Bioremediation tests indicated motor oil removal efficiency of over 80% on the temperature of 60 °C in its CMC, presenting excellent properties for the application in bioremediation.