Oil displacement properties of surfactin: a comparative study

Abstract Biosurfactants are amphiphilic compounds synthesized from plants and microorganisms and are known for their high biodegradability, low toxicity, and eco-friendliness. They have diverse applications in industrial and environmental fields, including oil recovery, bioremediation, and cleaning up hydrocarbons from polluted areas. Surfactin is a potent lipopeptide biosurfactant produced by Bacillus subtilis bacteria. In this study, we produced surfactin by B. subtilis using cassava wastewater as the fermentation medium. This production was monitored by high performance liquid chromatography (HPLC). Approximately 600 mg L−1 of surfactant was produced. The oil displacement test was then performed to evaluate the effectiveness of crude and purified surfactin compared to a synthetic surfactant and a biosurfactant. Three types of surfactants were tested: the synthetic surfactant sodium lauryl sulfate (SDS), the commercial biosurfactant rhamnolipid (Rh), and surfactin in its crude form and purified one – after acid precipitation. The analysis results indicated that surfactin, in both its crude and purified forms, was more effective at dispersing oil than the other surfactants tested, even at lower concentrations. This suggests that biosurfactants have great potential as a more sustainable and effective alternative to petroleum-derived synthetic surfactants. Surfactin can be applied without the need for downstream processes.