Formulation of a Biosurfactant-Based Biodetergent Using Surfactin From Bacillus Subtilis for Oil Contaminated Wastewater Bioremediation

Oil pollution poses severe threats to aquatic and terrestrial ecosystems, necessitating sustainable remediation strategies. The potential of Bacillus subtilis , which was isolated from tomato rhizosphere soil, for oil bioremediation and biosurfactant synthesis was examined in this work. The isolate was characterized through Gram staining, Plating in Bacillus Differentiation Agar, and Biochemical tests, confirming its identity as Bacillus subtilis . Screening assays, including hemolytic activity, oil displacement (74 mm clearance zone), emulsification (E24 index: 76.6%), and drop collapse tests, demonstrated robust surfactin production. GC-MS analysis identified (13Z)-13-Docosenamide as a key bioactive compound, contributing to hydrocarbon degradation. For bioremediation, oil-contaminated wastewater samples (gasoline, crude oil, kerosene and diesel) were treated with surfactin and monitored over four weeks. Optical density (OD) measurements revealed progressive oil degradation, with crude oil (WWS-2) showing the highest efficiency (OD reduction to 0.23). The study also formulated a powder-based biodetergent using surfactin (25–60%), Sapindus mukorossi (1% foaming agent), and a stabilizer (1.5%), demonstrating its applicability for industrial and household use. The findings highlight Bacillus subtilis as a promising candidate for eco-friendly oil spill remediation and biosurfactant-based product development.