Diesel degrading bacterial endophytes with plant growth promoting potential isolated from a petroleum storage facility
Thirteen (13) endophytic bacterial strains were isolated from Echinochloa crus-galli (Cockspur grass) and Cynodon dactylon (Bermuda grass) growing in an oil-contaminated site at a petroleum storage and transportation facility. Of the 13 strains assessed for their potential to degrade monoaromatic compounds (phenol, toluene, and xylene) and diesel and for their plant growth promoting (PGP) ability (phosphate solubilization, siderophores and 1-aminocyclopropane-1-carboxylate (ACC) deaminase production), isolate J10 (identified as Pseudomonas sp. by 16S rRNA gene sequencing) was found to the best diesel biodegrader with the best PGP traits. The Monod model used for Pseudomonas sp. J10 growth kinetics on diesel fuel as the sole carbon source showed that the maximum specific bacterial growth rate was 0.0644 h− 1 and the half velocity constant (Ks) was estimated as 4570 mg L− 1. The overall growth yield coefficient and apparent growth yield were determined to be 0.271 g h− 1 and 0.127 g cells/g substrate, respectively. Pseudomonas sp. J10 removed 69% diesel in four days as determined by gas chromatographic (GC) analysis. These findings could assist in developing an endophyte assisted efficient diesel biodegradation system using Pseudomonas sp. J10 isolated from Echinochloa crus-galli.
KeywordsEndophytic bacteria Diesel Phenol Toluene Xylene Phytoremediation
The authors would like to acknowledge the Higher Education Commission of Pakistan for financing this research through International Research Support Initiative Program. We thank Dr. Sergio Capareda and Dr. Amado Maglinao Jr. for Gas Chromatographic analysis.
AI: performed lab and field work, analyzed the data and wrote the manuscript. MA: supervised, advised lab work and data analyses. RK: advised biodegradation experiments, GC analysis and data analyses. TJG: advised lab work, experimental design and data analysis, JR: helped in GC and kinetic analysis, IA: helped in phylogenetic analysis of the strain, APS: supervised field work and data analyses.
Compliance with ethical standards
Conflict of interest
Authors declare that there are no competing financial as well as individual interests.
- Ahmed I, Sin Y, Paek J, Ehsan M, Hayat R, Iqbal M, Chang YH (2014) Description of Lysinibacillus pakistanensis. Int J Agric Biol 16:447–450Google Scholar
- Crueger W, Crueger A (1990) Biotechnology: a textbook of Industrial Microbiology, 2nd edn. English edition edited by Brock TD, Sinauer Associates, Sunderland, USA, pp 1–368Google Scholar
- Diaz-Ramos MC, Suarez A, Rubies A, Companyo R, Korte-McIllrick E (2012) Determination of 24 PAHs in drinking water. Agilent technologies application note #5990-7686EN: in sample prepration for chromatography book. https://www.agilent.com/cs/library/applications/5990-7686EN.pdf. Accessed 10 Feb 2017
- Lane D (1991) 16S\23S rRNA sequencing. In: Stackebrandt E, Goodfellow M (eds) Nucleic acid techniques in bacterial systematics. Wiley, Chichester, pp 115–147Google Scholar
- Pawlik M, Cania B, Thijs S, Vangronsveld J, Piotrowska-Seget Z (2017) Hydrocarbon degradation potential and plant growth-promoting activity of culturable endophytic bacteria of Lotus corniculatus and Oenothera biennis from a long-term polluted site. Environ Sci Pollut Res 24:19640–19652CrossRefGoogle Scholar
- USEPA (1996) Preliminary data summary for the petroleum refining category. EPA 821-R-96-015. U.S. EPA Office of Water, Wash. D.C. https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P100NV86.PDF. Accessed 16 Feb 2017
- USEPA (2014) Priority Pollutant List. https://www.epa.gov/sites/production/files/2015-09/documents/priority-pollutant-list-epa.pdf (Accessed on 10th November, 2017)