Bioremediation of Crude Oil-Polluted Soil with a Consortium of Pseudomonas Aeruginosa and Soybean Hull

This study investigates the bioremediation of crude oil-contaminated soil using Pseudomonas aeruginosa isolates with soybean hull as a biostimulant. The experimental setup included biostimulation, bioaugmentation, and hybrid approaches with bacterial strains KUD-1, KUD-2, KUD-3, and KUD-4. Molecular identification confirmed these strains as Pseudomonas aeruginosa. Over a five-week incubation period, key physicochemical properties, such as pH,electrical conductivity, moisture content, and levels of essential nutrients, were monitored. The results demonstrated significant reductions in toxic metals, with chromium (Cr+6) decreasing from 52.1 mg/kg to 13 mg/kg, iron (Fe) from 16,350 mg/kg to 560 mg/kg, and residual crude oil content from 0.51 g/10g to 0.11 g/10g. Improvements in soil fertility markers were also observed,with total nitrogen increasing from 126.6 mg/kg to 300 mg/kg, and total organic carbon rising from 0.761% to 6.55%. The pH of the soil increased from 6.28 to 7.78. This study underscores the effectiveness of biostimulation and bioaugmentation in enhancing the bioremediation process and restoring soil health, offering a sustainable solution for mitigating crude oil pollution.