Plant-enhanced phenanthrene and pyrene biodegradation in acidic soil

Area of Science:

• Environmental Microbiology
• Bioremediation
• Soil Science

Background:

• Polycyclic Aromatic Hydrocarbons (PAHs) like phenanthrene and pyrene are persistent soil pollutants.
• Acidic soils pose challenges for natural attenuation of PAH contamination.
• Corn (Zea mays L.) has shown resilience in PAH-contaminated acidic soils.

Purpose of the Study:

• To investigate the potential of corn plants to enhance PAH degradation in acidic soil.
• To evaluate the efficacy of Pseudomonas putida MUB1 in degrading phenanthrene and pyrene.
• To assess the synergistic effects of corn and MUB1 on PAH biodegradation.

Main Methods:

• Experimental setup involving corn planting, MUB1 inoculation, and a combination of both in acidic soil.
• Monitoring phenanthrene and pyrene removal rates over time.
• Comparison with control treatments (autoclaved and non-autoclaved soil).

Main Results:

• Corn plants and MUB1 individually enhanced phenanthrene and pyrene degradation compared to controls.
• The combined treatment of corn and MUB1 resulted in the highest biodegradation rates (89% phenanthrene, 88.2% pyrene) after 60 days.
• Initial degradation rates in the first 10 days were 41.7% (phenanthrene) and 38.8% (pyrene) with corn alone, and 58.8% (phenanthrene) and 53.6% (pyrene) with MUB1 alone.

Conclusions:

• Corn plants can significantly enhance the biodegradation of phenanthrene and pyrene in acidic soils.
• Inoculation with Pseudomonas putida MUB1 further boosts PAH degradation, especially when combined with corn.
• This combined approach offers a promising strategy for bioremediating PAH-contaminated acidic soils.