Gas Chromatographic evaluation of hydrocarbon degradation capabilities of Phyllosphere-derived Bacteria in simulated bioremediation of contaminated soil
Year: 2025
Type: article
Abstract: Monitoring hydrocarbon degradation is critical to assessing environmental pollution and the effectiveness of bioremediation strategies. Phyllosphere bacteria residing on plant surfaces have been shown to play a vital role in breaking down hydrocarbons; however, there is limited understanding of the compound-specific degradation patterns within the complex microbial communities present in the phyllosphere. This study evaluated the hydrocarbon-degrading capacities of four phyllosphere-derived isolates (Kocuria kristinae EN3, Pseudomonas oleovorans EP3, Pseudomonas aeruginosa EP4, and EP7) and a mixed-species consortium in comparison to natural attenuation in simulated bioremediation of contaminated soil (soil micrococosm) using Gas chromatography-flame ionization (GC-FID) analysis. Soil microcosms were amended with 5 g kg⁻¹ spent engine oil and inoculated with either individual isolates (~10⁸ CFU g⁻¹), the consortium (equal proportions of all four strains), or left uninoculated (natural attenuation). Incubation proceeded for 60 days at 28 °C under aerobic conditions. GC-FID analyzed hydrocarbon profiles at day 0 and day 60 to quantify relative peak areas and identify emergent byproducts. Results revealed that the consortium achieved a 2-fold increase in 1-Docosene (from 14.3% to 29.5% area) and produced shorter alkanes (Hexadecane, 0.20%; 1-Hexane, 0.99%). Individual strains displayed divergent patterns: EP3 eliminated mid-chain alkanes and generated halogenated byproducts (e.g., trichloromethane, 0.52%), EN3 uniquely accumulated a fluorinated ester (Octacosyl heptafluorobutyrate, 13.7%), and EP7 selectively enriched 1-Docosene (22.4%). Natural attenuation mirrored many effects of the consortium, with cyclic hydrocarbons (Cyclohexane) increasing from 0.71% to 15.2%, indicating substantial indigenous activity. In conclusion, this study highlights the efficacy of GC-FID in tracking hydrocarbon degradation and the potential of phyllosphere bacteria in bioremediation. Future research should focus on optimizing bacterial consortia for field-scale applications.
Authors: Baha’uddeen Salisu, Fatima Ibrahim, Musa Sani Kaware, Musa Isah
Language: English
Subfield: Pollution
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W6891616714