Bacterial-augmented phytoremediation of petroleum hydrocarbons using Triticum aestivum and Zea mays

Petroleum hydrocarbon contamination poses a major environmental challenge, necessitating sustainable bioremediation approaches. The present study aimed to evaluate the bioremediation potential of indigenous bacterial isolates from oil-contaminated soils and their synergistic effects with plants. Nineteen bacterial isolates were screened, among which Bacillus lentus (M8) and Paenibacillus curdlanolyticus (M9) exhibited superior hydrocarbon-degrading capabilities. In phytoremediation trials, microbial inoculation (M8/M9) restored wheat growth to 85% of controls in 5% oil-contaminated soil (OCS), though 10% OCS remained inhibitory (40% growth reduction). High performance liquid chromatography (HPLC) revealed extensive hydrocarbon transformation by M9 + maize, with new peaks (2.5-6.5 min) indicating metabolic activity, while gravimetry confirmed 86% degradation of 5% OCS by M9 + wheat at 60 days, surpassing bacteria-only treatments (60-67%). Overall, the results reveal that Bacillus-plant consortia effectively accelerate petroleum hydrocarbon degradation and promote soil recovery, offering a practical and eco-friendly solution for environmental restoration.