Abstract:
This study investigated the bioremediation of oil polluted soil with piggery manure at control, 50g, 100g and 150g on 5% and 10% concentrations of engine oil; and the biodegradative abilities of the indigenous bacteria were monitored through physichochemical properties and gas chromatography mass spectrophotometry (GCMS). The bacteria isolated from the polluted soil were Bacillus subtilis, Bacillus cereus, Micrococcus luteus, Pseudomonas aeruginosa, Proteus vulgaris, Escherichia coli, Serratia marcescens, and Staphylococcus aureus. The bacteria with the highest frequency of occurrence were P. aeruginosa and M. luteus at 21.96% and 19.78% respectively with S. marcescens and P. vulgaris having the least frequency of occurrence. M. luteus degraded the engine oil best at 73.71% at 96 hours of incubation with Minimal Salt Medium (MSM) broth. The pH values for the soil polluted at 5% and 10% containing piggery manure reduced after bioremediation from 8.0 to 5.6 and 8.3 to 5.5 respectively. The organic carbon, organic matter, nitrogen, potassium, phosphorus, oil and grease and moisture content significantly decreased after bioremediation of the polluted soil. The GCMS revealed that the control sample had a larger quantity of C21 – C25 carbon compounds while the treated samples had smaller quantities of C16 – C18 carbon compounds after bioremediation over a period of 90 days signifying degradation. The findings from this study, suggest that piggery manure may be effective as a biostimulant in the bioremediation of engine oil polluted soils.
