INVESTIGATION OF BIOREMEDIATION POTENTIAL OF WHEY DERIVED FROM PANICUM MAXIMUM ON CRUDE OIL CONTAMINATED SOIL

Crude oil spills in Nigeria poison farmland, killing plants and microbes while adding dangerous hydrocarbons and heavy metals that hurt crops and human health. This study tests a low-cost, eco-friendly fix using fermented whey from guinea grass (Panicum maximum) leaves to boost soil microbes that eat oil. The aim was to see how well this whey cleans oil-polluted soil by cutting total petroleum hydrocarbons (TPH) and restoring soil quality. The scope included collecting leaves (Panicum maximum) from University of Benin sports complex, processing the leaves into whey and fermenting the whey at various periods for twelve days. The whey samples were further characterized to further determine pH, electrical conductivity, moisture, organic matter, carbon, nitrate, phosphate, nitrogen, phosphorus, potassium, and microbial counts to evaluate the whey with the best potential with respect to fermentation time—day 12 with pH 5.74, EC 4804 µS/cm, TOC 67.27%, nitrate 394.17 mg/kg, and high microbial growth (819 CFU/ml at 10⁻¹). Bioremediation potential of the whey was evaluated by treating agricultural soil. The day-12 whey results showed that soil treated with 200 ml was best, raising pH from 5.21 to 7.19, nitrogen from 19.10 to 27.18 mg/kg, phosphorus from 12.65 to 14.98 mg/kg, potassium from 6.23 to 12.45 mg/kg. TPH results showed that hexatriacontane rose to 1.17mg/L increased in the treated soil compared to the untreated contaminated soil, indicating its formation as a biodegradation intermediate during the breakdown of heavier hydrocarbons. Hexatriacontane showed a significant reduction to 0.05mg/L after whey treatment, demonstrating effective microbial attack on heavy hydrocarbon fractions. Heavy metals analysis indicates a significant reduction in metal concentration as in iron from 45.67mg/kg to 32.45mg/kg, zinc 18.90 mg/kg to 12.34 mg/kg copper 7.56 mg/kg to 5.12 mg/kg. Day 12 fermented Panicum maximum whey gave the best remediation potential.