Development of a bacterial consortium comprising oil-degraders and diazotrophic bacteria for elimination of exogenous nitrogen requirement in bioremediation of diesel-contaminated soil

• Published in: World journal of microbiology & biotechnology Vol. 35; no. 7; pp. 99 - 11
• Main Authors: Chaudhary, Dhiraj Kumar, Bajagain, Rishikesh, Jeong, Seung-Woo, Kim, Jaisoo
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.07.2019; Springer Nature B.V
• Subjects: Acinetobacter - metabolism; Ammonium nitrate; Applied Microbiology; Azotobacter; Azotobacter vinelandii - metabolism; Bacteria; Biochemistry; Biodegradation, Environmental; Biomedical and Life Sciences; Bioremediation; Biotechnology; Consortia; Content analysis; Degradation; Diesel; Environmental Engineering/Biotechnology; Gasoline - analysis; Life Sciences; Microbiology; Nitrogen; Nitrogen - metabolism; Nitrogen-Fixing Bacteria - metabolism; Oil; Original Paper; Rhodococcus; Rhodococcus - metabolism; Soil - chemistry; Soil contamination; Soil Microbiology; Soil Pollutants - chemistry; Soil pollution; Soil remediation; Soil treatment; Bacterial consortia; Oil-degrading microbe; Diesel; Diazotrophic bacteria; Bioremediation; Nitrogen limitation
• ISSN: 0959-3993; 1573-0972
• DOI: 10.1007/s11274-019-2674-1

The purpose of this study was to develop an effective bacterial consortium and determine their ability to overcome nitrogen limitation for the enhanced remediation of diesel-contaminated soils. Towards this, various bacterial consortia were constructed using oil-degrading and nitrogen-fixing microbes. The diesel removal efficiency of various developed consortia was evaluated by delivering the bacterial consortia to the diesel-contaminated soils. The consortium Acinetobacte r sp. K-6 +  Rhodococcus sp. Y2-2 + NH 4 NO 3 resulted in the highest removal (85.3%) of diesel from the contaminated soil. The consortium containing two different oil-degrading microbes (K-6 + Y2-2) and one nitrogen-fixing microbe Azotobacter  vinelandii KCTC 2426 removed 83.1% of the diesel from the soil after 40 days of treatment. The total nitrogen content analysis revealed higher amounts of nitrogen in soil treated with the nitrogen-fixing microbe when compared with that of the soil supplemented with exogenous inorganic nitrogen. The findings in this present study reveal that the consortium containing the nitrogen-fixing microbe degraded similar amounts of diesel to that degraded by the consortium supplemented with exogenous inorganic nitrogen. This suggests that the developed consortium K-6 + Y2-2 + KCTC 2426 compensated for the nitrogen limitation and eliminated the need for exogenous nitrogen in bioremediation of diesel-contaminated soils. Graphic abstract