Research Article
IsolationandCharacterizationofDiesel-DegradingBacteriafrom
Hydrocarbon-ContaminatedSites,FlowerFarms,andSodaLakes
Gessesse Kebede Bekele ,
1
Solomon Abera Gebrie ,
1
Eshetu Mekonen ,
2
TekleTafeseFida ,
1
Adugna Abdi Woldesemayat ,
1
EbrahimM.Abda ,
1
Mesfin Tafesse ,
1
andFasilAssefa
3
1
DepartmentofBiotechnology,CollegeofBiologicalandChemicalEngineering,AddisAbabaScienceandTechnologyUniversity,
Addis Ababa, Ethiopia
2
Department of Biology, Dire Dawa University, College of Natural and Computational Sciences, Dire Dawa, Ethiopia
3
Microbial,Cellular and Molecular Biology Department, Addis Ababa University, Addis Ababa, Ethiopia
Correspondence should be addressed to Gessesse Kebede Bekele; gessesekebede@gmail.com
Received 26 September 2021; Revised 20 December 2021; Accepted 3 January 2022; Published 21 January 2022
Academic Editor: Todd R. Callaway
Copyright©2022GessesseKebedeBekeleetal.isisanopenaccessarticledistributedundertheCreativeCommonsAttribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is
properly cited.
Hydrocarbon-derived pollutants are becoming one of the most concerning ecological issues. us, there is a need to investigate and
develop innovative, low-cost, eco-friendly, and fast techniques to reduce and/or eliminate pollutants using biological agents. e study
was conducted to isolate, characterize, and identify potential diesel-degrading bacteria. Samples were collected from flower farms,
lakeshores, old aged garages, asphalt, and bitumen soils and spread on selective medium (Bushnell Haas mineral salt agar) containing
diesel as the growth substrate. e isolates were characterized based on their growth patterns using optical density measurement,
biochemical tests, and gravimetric analysis and identified using the Biolog database and 16S rRNA gene sequencing techniques.
Subsequently, six diesel degraders were identified and belong to Pseudomonas, Providencia, Roseomonas, Stenotrophomonas, Ach-
romobacter, and Bacillus. Among these, based on gravimetric analysis, the three potent isolates AAUW23, AAUG11, and AAUG36
achieved 84%, 83.4%, and 83% diesel degradation efficiency, respectively, in 15 days. Consequently, the partial 16S rRNA gene
sequences revealed that the two most potent bacterial strains (AAUW23 and AAUG11) were Pseudomonasaeruginosa, while AAUG36
was Bacillus subtilis. is study demonstrated that bacterial species isolated from hydrocarbon-contaminated and/or uncontaminated
environments could be optimized to be used as potential bioremediation agents for diesel removal.
1.Background
Hydrocarbons, such as polycyclic aromatic hydrocarbons
(PAHs), benzene, kerosene, and diesel are important organic
pollutants and inputs for different industries, vehicles, and
household activities as a source of energy [1–8]. Among
these, diesel is massively used for engine, fuel, and industrial
applications. It is one of the products of petroleum com-
pounds formed during fractional distillation of crude oil and
is composed of a mixture of carbon chains between 9 and 25
carbon atoms that may include both aromatic and aliphatic
hydrocarbon components [4, 6, 9]. ese hydrocarbon
components can be discharged into the environment
(groundwater, soil, and air) from different sources (point
and nonpoint), such as garages, gas station services,
chemical and petrochemical industries, agricultural waste,
automobile exhaust spillage of petroleum, run-off asphalt
pavements, vehicular emission, and combustion of fossil fuel
[10–12]. is phenomenon may happen intentionally or
accidentally mainly from anthropogenic activities because of
urbanization, industrialization, and civilization
[3, 10, 11, 13–15] and, to some extent, by natural disasters
[16]. As a result, hydrocarbon-derived pollutants are
immuno-toxicant, mutagenic, and carcinogenic to humans
and animals and affect natural ecosystem functioning in
many ways [2–4, 6, 7, 14, 15, 17–21].
Hindawi
International Journal of Microbiology
Volume 2022, Article ID 5655767, 12 pages
https://doi.org/10.1155/2022/5655767