Remediation Rates of Microbes in Polluted Crude Oil Soil

Removal rate of Total Petroleum Hydrocarbon Content (TPHC) of a crude oil polluted land was
investigated with field experimental data generated from the Research Farm soil at the Federal
University of Technology Owerri, Imo State, Nigeria. The artificially polluted soil using crude oil -
bonny light - with specific gravity of 0.8323 was analyzed. The petroleum contaminant present in the
laboratory soil was 230 mg per kilogram of soil. The other treatment variables used include: Inorganic
fertilizer -FZ (NPK 20:10:10), poultry manure -MP, cow dung -CD and a mixture of the three (ie FZ,
PM & CD) in equal proportion. In addition, natural treatment was allowed to occur as the control
experiment. However, fungi as well as bacteria played an important role in the degradation of
petroleum hydrocarbon. The identified crude oil degrading Fungi are Penicillium notatum, Mucor spp,
Rhizopus stolonifer and Penicillum caseicolum with P. notatum and P. caseicolum (penicillum spp) as
the strongest fungi degraders. On the other hand, the identified degrading Bacteria are Pseudomonas
putida and Bacillus subtilis. These can therefore be isolated and cultured and then employed on
remediation sites either as indigenous or foreign degrading microbes in the engineering of
bioremediation of crude oil polluted soil using the best engineering techniques. The treatment with
mixture of treatment variables proved to be a better option from the results obtained with 82.38 mg/kg
after 9 weeks of remediation followed by fertilizer, 83.13 mg/kg and 86.75 mg/kg for poultry manure.
Cow dung had 105.5 mg/kg and the control had least with 204.50 mg/kg.