Bioremediation of polycyclic aromatic hydrocarbon (PAH) compounds: (acenaphthene and fluorene) in water using indigenous bacterial species isolated from the Diep and Plankenburg rivers, Western Cape, South Africa

Abstract

This study was conducted to investigate the occurrence of PAH degrading microorganisms in two river systems in the Western Cape, South Africa and their ability to degrade two PAH compounds: acenaphthene and fluorene. A total of 19 bacterial isolates were obtained from the Diep and Plankenburg rivers among which four were identified as acenaphthene and fluorene degrading isolates. In simulated batch scale experiments, the optimum temperature for efficient degradation of both compounds was determined in a shaking incubator after 14 days, testing at 25 °C, 30 °C, 35 °C, 37 °C, 38 °C, 40 °C and 45 °C followed by experiments in a Stirred Tank Bioreactor using optimum temperature profiles from the batch experiment results. All experiments were run without the addition of supplements, bulking agents, biosurfactants or any other form of biostimulants. Results showed that Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila efficiently degraded both compounds at 37 °C, 37 °C, 30 °C and 35 °C respectively. The degradation of fluorene was more efficient and rapid compared to that of acenaphthene and degradation at Stirred Tank Bioreactor scale was more efficient for all treatments. Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila degraded a mean total of 98.60%, 95.70%, 90.20% and 99.90% acenaphthene, respectively and 99.90%, 97.90%, 98.40% and 99.50% fluorene, respectively. The PAH degrading microorganisms isolated during this study significantly reduced the concentrations of acenaphthene and fluorene and may be used on a larger, commercial scale to bioremediate PAH contaminated river systems.

Isolation and Characterization of Phenanthrene Degrading Bacteria from Diesel Fuel-Contaminated Antarctic Soils

“…Various hydrocarbon-degrading bacteria have been isolated to date from Antarctica, including Rhodococcus, Acinetobacter, Pseudomonas , and Sphingomonas species (Aislabie et al, 2006 ). The use of serial PAH-supplemented growth media enrichments, and the highly selective growth condition of utilizing PAHs as sole energy source, have permitted to establish successful approaches to isolate nalovel PAH-degrading bacteria of interest from varied environmental sources (Obi et al, 2016 ; Alegbeleye et al, 2017 ; Li et al, 2017 ; Oyehan and Al-Thukair, 2017 ). Additionally, new techniques of in situ microculturing have allowed to culture an even broader number of PAH-degrading organisms by recreating the native conditions of growth, allowing growth of bacteria not normally isolated using standard culture conditions (van Dorst et al, 2016 ).…”

Advances in water treatment technologies for removal of polycyclic aromatic hydrocarbons: Existing concepts, emerging trends, and future prospects

“…A recent study revealed that degradation of PAHs by Aeromonas hydrophila , Bacillus megaterium , Raoultella ornithinolytica , and Serratia marcescens recorded over 90% degradation efficiency for fluorene and acenaphthene (Alegbeleye, Opeolu, & Jackson, 2017). However, certain environmental variables such as temperature and pH were reported to have a considerable influence on the efficiency of the bioremediation processes.…”

Rhizodegradation of Pyrene by a Non-pathogenic Klebsiella pneumoniae Isolate Applied With Tagetes erecta L. and Changes in the Rhizobacterial Community

“…The use of microorganisms for remediation of PAHs has been regarded as the main natural degradation method in soils, as native microorganisms could utilize bioavailable PAHs as their sole source of carbon ( Haritash and Kaushik, 2009 ). Several bacterial species ( Acinetobacter , Alcanivorax , Cellulomonas , Deitzia , Micrococcus , Marinobacter , Pseudomonas , Paenibacillus , Sphingomonas ) have been reported for degrading PAHs ( Maki et al, 2010 ; Alegbeleye et al, 2017 ). Mycobacterium spp.…”