Mycoremediation of Spent Lubricating Oil Contaminated Soil Using Pleurotus ostreatus

This study was conducted to evaluate the remediation capability of Pleurotus ostreatus on spent lubricating oil polluted soil. Twenty percent (v/w) lubricating oil was spiked into 100 g of garden soil, inoculated with P. ostreatus pre-grown with sawdust as a substrate. The changes in pH, moisture content, total petroleum hydrocarbon, percentage total organic carbon, nitrate and phosphate concentrations were monitored biweekly for 84 days. Results obtained showed an increase of pH from 6.21 to 6.79. Total petroleum hydrocarbon concentration reduced by 72.5% from 2892.10mg/kg at day 1 to 796.66mg/kg at day 84. The percentage TOC increased by 73.3% from 3.16% to 5.467% while there was decrease in moisture content from 24.81% to 10.80% (56.5% reduction). There was 62% decrease in the concentration of phosphate from 18.80mg/kg to 7.14mg/kg while 5.4% decrease in nitrate concentration from 89.48mg/kg to 84.68mg/kg was observed. Analysis of variance (ANOVA) showed an overall significant difference between the concentration changes over time at 95% confidence interval. The results of this study proved the capability of P. ostreatus as an effective remediation tool for the recovery of hydrocarbon impacted soil.