Hydrocarbon degradation in oily sludge by bacterial consortium assisted with alfalfa ( Medicago sativa L.) and maize ( Zea mays L.)

Hydrocarbons contamination is a worldwide threat to soil ecosystem. The present study was designed to evaluate the remediation potential of bacterial consortium, viz. Bacillus cereus (Acc KR232400), Bacillus altitudinis (Acc KF859970), Commomonas ( Delftia sp.) (Acc KF859971), and Stenotrophomonas maltophilia (Acc KF859973), with alfalfa and maize plants in combination with fertilizer to remediate the oily sludge. Oily sludge was mixed with soil in 30:70 ratio, and ammonium nitrate and diammonium phosphate (DAP) were added at a rate of 70 μg/g and 7 μg/g with the consortium (10 6 cells/ml). Different hydrocarbons were extracted by Soxhlet extraction and examined by using gas chromatography and flame ionization detector (GC-FID). Consortium degraded more than 63% total petroleum hydrocarbons, and significant degradation (80%) of n -alkanes ( n C 13 to n C 29 ) was witnessed with consortium + fertilizer + alfalfa in 30% oily sludge at 3 days. Degradation of (80%) of n -alkanes ( n C 13 to n C 29 ) in oily sludge was also noted. In this study, the consortium along with Alfalfa and fertilizer found most efficient option for remediation of hydrocarbons.