Degradation of poly aromatic fractions of crude oil and detection of catabolic genes in hydrocarbon-degrading bacteria isolated from Agbabu bitumen sediments in Ondo State.

Temitayo O Olowomofe,B.I Aderiye,O A Oluwole,J O Oluyege

doi:10.3934/microbiol.2019.4.308

Temitayo O Olowomofe, B.I Aderiye + Show 2 more

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https://doi.org/10.3934/microbiol.2019.4.308

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Journal: AIMS microbiology	Publication Date: Jan 1, 2019
Citations: 23	License type: cc-by

Affiliation: Ekiti State University

Abstract

Pollution due to release of Poly aromatic hydrocarbons (PAHs) are a major environmental issue especially in oil producing communities. This study investigates the polyaromatic hydrocarbon degradation potentials of some bacteria: Campylobacter hominis, Bacillus cereus, Dyadobacter koreensis, Pseudomonas aeruginosa and Micrococcus luteus isolated from Agbabu bitumen sediments in Ondo State. The isolates were used singly and in consortium for the degradation of Bonny light crude oil. Concentrations of residual aromatic hydrocarbons in crude oil degraded by these isolates were determined by Gas chromatography/Mass Spectroscopy with flame ionization detector (FID). Detection of catabolic genes (nahH, CatA and AlkB) in the isolates was determined by PCR amplification of their specific primers. The GC-MS analyses showed degradation of poly aromatic hydrocarbons (PAHs) by these isolates. The consortium exhibited the highest PAH reduction (73%) while C. hominis had the least PAH reduction (56%). Dyadobacter koreensis, P. aeruginosa, Micrococcus luteus and B. cereus, displayed 66%, 60%, 59% and 58% PAH reduction respectively. The catabolic gene nahH gene was present in B. cereus, D. koreensis, P. aeruginosa and M. luteus, alkB gene was present in B. cereus, C. hominis, and D. koreensis while CatA was not detected in any of the isolates. The findings of this study affirmed the hydrocarbon-degrading abilities and presence of catabolic genes in these bacteria, these make them potential tools in oil prospecting and cleaning up of hydrocarbon contaminated sites.

Highlights

Pollution caused by crude oil and its derivatives are the most widespread problem in aquatic and terrestrial ecosystems and are a huge source of environmental concern worldwide [1]
This study investigates the polyaromatic hydrocarbon degradation potentials of some bacteria: Campylobacter hominis, Bacillus cereus, Dyadobacter koreensis, Pseudomonas aeruginosa and Micrococcus luteus isolated from Agbabu bitumen sediments in Ondo State
A major concern during petroleum hydrocarbon pollution is the presence of heavy compounds such as polycyclic aromatic hydrocarbons (PAHs), asphaltenes and many branched compounds with twenty or more carbon atoms which are relatively resistant to biodegradation and may move up marine food chains and taint fishes or shellfishes, which further can be used as food or feed, and can harm higher life forms through biomagnifications [4,5]

Summary

Introduction

Pollution caused by crude oil and its derivatives are the most widespread problem in aquatic and terrestrial ecosystems and are a huge source of environmental concern worldwide [1]. Current conventional remediation approaches include physicochemical techniques such as photo-oxidation, burying, dispersion, washing, incineration, thermal conversion and other pyrolysis techniques [8]. Their high cost of application and the resultant toxic intermediates being generated make them largely unsuitable. Bioremediation, defined as the use of microorganisms to detoxify or remove pollutants is regarded as a preferable alternative due to its low cost, high efficiency, environmental friendliness and simplicity technology for long term restoration of crude oil contaminated sites [9]. Being known to be hydrocarbonoclastic [11], microorganisms offer an alternative solution to the problems of clean up [12]

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