Bioremediation of Spent Engine Oil Contaminated Soil by Using Fungus, Penicillium sp.

This study investigated the ability of Penicillium sp. to bio-remediate spent engine oil contaminated soil both in vitro and in vivo. In the in vitro assay, mycelium of a seven day old culture of Penicillium sp. grown on Sabouraud Dextrose Agar (SDA) was punched out using a 0.5mm Cork borer and inoculated on the centre of Petri dishes containing the spent and unspent engine oil and incubated for seven days and daily reading of the mycelia growth obtained using a metre rule. For the in vivo assay, soil received 0 (control), 20/180, 40/360, 60/540, 80/720 and 100ml/900mm concentrations/treatments (inoculation with mycelium of Penicillium sp.). Seeds of Telfeira occidentalis was sown on the soil and assessed for growth performance (plant height, leaf area (using a metre rule) and leaf count (number of leaves) for 7, 14, 21 and 28 Days after Planting (DAP). Results of the in vitro assay showed a significant increase (p<0.05) in the growth diameter of Penicillium sp. relative to control. Results of the in vivo assay showed that spent engine oil had no significant effect (p<0.05) on the growth performance of T. occidentalis at 7, 14, 21 and 28 DAP and on fresh and dry weight (g) 28 DAP relative to control. After 28 days of plant growth, the added spent engine oil was no longer detected. The plant began producing pods 61 DAP. This study showed that Penicillium sp. can biodegrade hydrocarbons present in spent engine oil and as such is a good tool for bioremediation.