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Wei YF, Wang L, Xia ZY, Gou M, Sun ZY, Lv WF, Tang YQ. Microbial communities in crude oil phase and filter-graded aqueous phase from a Daqing oilfield after polymer flooding. J Appl Microbiol 2022; 133:842-856. [PMID: 35490352 DOI: 10.1111/jam.15603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/23/2022] [Accepted: 04/27/2022] [Indexed: 12/01/2022]
Abstract
AIMS The aim was to characterize indigenous microorganisms in oil reservoirs after polymer flooding (RAPF). METHODS The microbial communities in the crude oil phase (Oil) and in the filter-graded aqueous phases Aqu0.22 (>0.22 μm) and Aqu0.1 (0.1~0.22 μm) were investigated by 16S rRNA gene high-throughput sequencing. RESULTS Indigenous microorganisms related to hydrocarbon degradation prevailed in the three phases of each well. However, obvious differences of bacterial compositions were observed among the three phases of the same well and among the same phase of different wells. The crude oil and Aqu0.22 shared many dominant bacteria. Aqu0.1 contained a unique bacterial community in each well. Most bacteria in Aqu0.1 were affiliated to culturable genera, suggesting that they may adapt to the oil reservoir environment by reduction of cell size. Contrary to the bacterial genera, archaeal genera were similar in the three phases but varied in relative abundances. The observed microbial differences may be driven by specific environmental factors in each oil well. CONCLUSIONS The results suggest an application potential of microbial enhanced oil recovery (MEOR) technology in RAPF. The crude oil and Aqu0.1 contain many different functional microorganisms related to hydrocarbon degradation. Both should not be overlooked when investing and exploring the indigenous microorganisms for MEOR. SIGNIFICANCE AND IMPACT OF THE STUDY This work facilitates the understanding of microbial community structures in RAPF and provides information for microbial control in oil fields.
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Affiliation(s)
- Yan-Feng Wei
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Lu Wang
- State Key Laboratory of Enhanced Oil Recovery, Research Institute of Petroleum Exploration and Development, CNPC, Beijing 100083, China
| | - Zi-Yuan Xia
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Min Gou
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Zhao-Yong Sun
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
| | - Wei-Feng Lv
- State Key Laboratory of Enhanced Oil Recovery, Research Institute of Petroleum Exploration and Development, CNPC, Beijing 100083, China
| | - Yue-Qin Tang
- College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu, Sichuan 610065, China
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2
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Chen X, Ye Q, Sanders CJ, Du J, Zhang J. Bacterial-derived nutrient and carbon source-sink behaviors in a sandy beach subterranean estuary. MARINE POLLUTION BULLETIN 2020; 160:111570. [PMID: 32861939 DOI: 10.1016/j.marpolbul.2020.111570] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/01/2020] [Accepted: 08/11/2020] [Indexed: 06/11/2023]
Abstract
Microbial communities in subterranean estuaries play important roles in the biogeochemical cycle. However, the microorganisms associated with biogeochemical behaviors in subterranean estuaries have received little attention. Here, the bacterial communities were compared between the fresh and saline groundwater in a subterranean estuary. Correlation analysis between bacterial groups and salinity indicated that different species represented different groundwater types. The key bacterial groups found along the subterranean estuaries have been shown to influence organic pollutant degradation and nitrate utilization. These species may be potential candidates for the in situ bioremediation of subterranean estuaries that are contaminated with pollutants. The utilization of nitrate and organic pollutants by bacteria in subterranean estuaries serves as a nitrate sink and inorganic carbon source. Our results show the role of bacteria in remediating pollutants through submarine groundwater discharge (SGD) to the coastal ocean, and specific species may be helpful in selecting reasonable groundwater end-members and reducing SGD uncertainties.
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Affiliation(s)
- Xiaogang Chen
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China; School of Engineering, Westlake University, Hangzhou 310024, China
| | - Qi Ye
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China.
| | - Christian J Sanders
- National Marine Science Centre, Southern Cross University, Coffs Harbour, NSW 2450, Australia
| | - Jinzhou Du
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China; Institute of Eco-Chongming (IEC), Shanghai 202162, China
| | - Jing Zhang
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China
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3
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Raths R, Peta V, Bücking H. Massilia arenosa sp. nov., isolated from the soil of a cultivated maize field. Int J Syst Evol Microbiol 2020; 70:3912-3920. [DOI: 10.1099/ijsem.0.004266] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Strain MC02T, a Gram-stain-negative, rod-shaped bacterium, was isolated from field soil collected from California, USA. To examine if MC02T represents a novel species, we compared its colony morphology, 16S rRNA gene and whole genome sequence, and its metabolic phenotype using Biolog GenIII and MALDI-TOF analyses compared to reference strains. Based on 16S rRNA gene and whole genome sequencing, MC02T belongs to the genus
Massilia
and
Massilia agri
K-3–1T is the most similar strain with 96.97 % 16S rRNA gene sequence identity. MALDI-TOF analysis revealed that
Massilia aerilata
DSM19289T is the closest match, but the similarity score was much lower than the ≥1.7 threshold for a reliable identification at the genus level. The predominant fatty acids were summed feature 3 (C16 : 1⍵7c and/or C16 : 1⍵6c; 49.07 %) and C16 : 0 (30.01 %). The genome is 5.02 Mbp and the G+C content is 66.2 mol%. Whole genome comparisons to the closest related strains revealed an average amino acid identity value of 67.4 %, an OrthoANI similarity of 77.1 %, and a DNA–DNA-hybridization probability ≥70 %, confirming that MC02T represents a novel species. Strain MC02T can grow at pH 6 but not at pH 5, and a salt concentration of ≥1 % inhibits its growth. In contrast to other
Massilia
strains, MC02T can utilize turanose, inosine and l-serine. The genome of MC02T shows putative endophyte genes such as a nitrate reductase, several phosphatases, and biotin biosynthesis genes, 26 flagellar motility genes and 14 invasion and intracellular resistance genes. Based on its metabolic, physiological and genomic characteristics, we propose that strain MC02T (NRRL B-65554T=ATCC TSD-200T=LMG 31737T) represents a novel species of the genus
Massilia
with the name Massilia arenosa sp. nov.
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Affiliation(s)
- Rachel Raths
- South Dakota State University, Biology and Microbiology Department, Brookings, SD 57007, USA
| | - Vincent Peta
- South Dakota State University, Biology and Microbiology Department, Brookings, SD 57007, USA
| | - Heike Bücking
- South Dakota State University, Biology and Microbiology Department, Brookings, SD 57007, USA
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Zhan H, Huang Y, Lin Z, Bhatt P, Chen S. New insights into the microbial degradation and catalytic mechanism of synthetic pyrethroids. ENVIRONMENTAL RESEARCH 2020; 182:109138. [PMID: 32069744 DOI: 10.1016/j.envres.2020.109138] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 12/23/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
The significant applications of pyrethroid insecticides in agro-ecosystem and household environments have raised serious environmental concerns. Environmental bioremediation has emerged as an effective and eco-friendly approach to remove or neutralize hazardous compounds. Bioaugmentation accelerates pyrethroid degradation in liquid cultures and soil. Pyrethroid-degrading microorganisms have been extensively studied to cope with pyrethroid residues. Microorganisms primarily hydrolyze the ester bonds of pyrethroids, and their degradation pathways have been elaborated. The functional genes and enzymes involved in microbial degradation have also been screened and studied. Carboxylesterase plays a key role in pyrethroid degradation by cleaving its carboxylester linkage. The catalytic mechanism is dependent on a specific catalytic triad, consisting of three amino acid residues (glutamine, histidine, and serine) within the active site of the carboxylesterase enzyme. Pyrethroid-degrading strains and enzymes have proven to be effective for the bioremediation of pyrethroid-contaminated environments. In this review, we have summarized newly isolated pyrethroid-degrading strains and proposed the degradation pathways along with key functional genes/enzymes. To develop an efficient bioremediation strategy, pyrethroid-degrading microorganisms should be comprehensively explored.
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Affiliation(s)
- Hui Zhan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, PR China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, PR China
| | - Yaohua Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, PR China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, PR China
| | - Ziqiu Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, PR China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, PR China
| | - Pankaj Bhatt
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, PR China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, PR China
| | - Shaohua Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, PR China; Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, 510642, PR China.
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Brzeszcz J, Kapusta P, Steliga T, Turkiewicz A. Hydrocarbon Removal by Two Differently Developed Microbial Inoculants and Comparing Their Actions with Biostimulation Treatment. Molecules 2020; 25:E661. [PMID: 32033085 PMCID: PMC7036810 DOI: 10.3390/molecules25030661] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/30/2020] [Accepted: 02/01/2020] [Indexed: 01/21/2023] Open
Abstract
Bioremediation of soils polluted with petroleum compounds is a widely accepted environmental technology. We compared the effects of biostimulation and bioaugmentation of soil historically contaminated with aliphatic and polycyclic aromatic hydrocarbons. The studied bioaugmentation treatments comprised of the introduction of differently developed microbial inoculants, namely: an isolated hydrocarbon-degrading community C1 (undefined-consisting of randomly chosen degraders) and a mixed culture C2 (consisting of seven strains with well-characterized enhanced hydrocarbon-degrading capabilities). Sixty days of remedial treatments resulted in a substantial decrease in total aliphatic hydrocarbon content; however, the action of both inoculants gave a significantly better effect than nutrient amendments (a 69.7% decrease for C1 and 86.8% for C2 vs. 34.9% for biostimulation). The bioaugmentation resulted also in PAH removal, and, again, C2 degraded contaminants more efficiently than C1 (reductions of 85.2% and 64.5%, respectively), while biostimulation itself gave no significant results. Various bioassays applying different organisms (the bacterium Vibrio fischeri, the plants Sorghum saccharatum, Lepidium sativum, and Sinapis alba, and the ostracod Heterocypris incongruens) and Ames test were used to assess, respectively, potential toxicity and mutagenicity risk after bioremediation. Each treatment improved soil quality, however only bioaugmentation with the C2 treatment decreased both toxicity and mutagenicity most efficiently. Illumina high-throughput sequencing revealed the lack of (C1) or limited (C2) ability of the introduced degraders to sustain competition from indigenous microbiota after a 60-day bioremediation process. Thus, bioaugmentation with the bacterial mixed culture C2, made up of identified, hydrocarbon-degrading strains, is clearly a better option for bioremediation purposes when compared to other treatments.
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Affiliation(s)
- Joanna Brzeszcz
- Department of Microbiology, Oil and Gas Institute–National Research Institute, ul. Lubicz 25A, 31-503 Krakow, Poland;
| | - Piotr Kapusta
- Department of Microbiology, Oil and Gas Institute–National Research Institute, ul. Lubicz 25A, 31-503 Krakow, Poland;
| | - Teresa Steliga
- Department of Reservoir Fluid Production Technology, Oil and Gas Institute–National Research Institute, ul. Lubicz 25 A, 31-503 Krakow, Poland;
| | - Anna Turkiewicz
- Department of Microbiology, Oil and Gas Institute–National Research Institute, ul. Lubicz 25A, 31-503 Krakow, Poland;
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Aanderud ZT, Bahr J, Robinson DM, Belnap J, Campbell TP, Gill RA, McMillian B, St. Clair S. The Burning of Biocrusts Facilitates the Emergence of a Bare Soil Community of Poorly-Connected Chemoheterotrophic Bacteria With Depressed Ecosystem Services. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00467] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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7
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Dashti N, Ali N, Salamah S, Khanafer M, Al-Shamy G, Al-Awadhi H, Radwan SS. Culture-independent analysis of hydrocarbonoclastic bacterial communities in environmental samples during oil-bioremediation. Microbiologyopen 2018; 8:e00630. [PMID: 29656601 PMCID: PMC6391274 DOI: 10.1002/mbo3.630] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/14/2018] [Accepted: 02/28/2018] [Indexed: 11/09/2022] Open
Abstract
To analyze microbial communities in environmental samples, this study combined Denaturing Gradient Gel Electrophoresis of amplified 16S rRNA-genes in total genomic DNA extracts from those samples with gene sequencing. The environmental samples studied were oily seawater and soil samples, that had been bioaugmented with natural materials rich in hydrocarbonoclastic bacteria. This molecular approach revealed much more diverse bacterial taxa than the culture-dependent method we had used in an earlier study for the analysis of the same samples. The study described the dynamics of bacterial communities during bioremediation. The main limitation associated with this molecular approach, namely of not distinguishing hydrocarbonoclastic taxa from others, was overcome by consulting the literature for the hydrocarbonoclastic potential of taxa related to those identified in this study. By doing so, it was concluded that the hydrocarbonoclastic bacterial taxa were much more diverse than those captured by the culture-dependent approach. The molecular analysis also revealed the frequent occurrence of nifH-genes in the total genomic DNA extracts of all the studied environmental samples, which reflects a nitrogen-fixation potential. Nitrogen fertilization is long known to enhance microbial oil-bioremediation. The study revealed that bioaugmentation using plant rhizospheres or soil with long history of oil-pollution was more effective in oil-removal in the desert soil than in seawater microcosms.
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Affiliation(s)
- Narjes Dashti
- Microbiology program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Nedaa Ali
- Microbiology program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Samar Salamah
- Microbiology program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Majida Khanafer
- Microbiology program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Ghada Al-Shamy
- Microbiology program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Husain Al-Awadhi
- Microbiology program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Samir S Radwan
- Microbiology program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
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8
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Radwan SSA, Al-Mailem DM, Kansour MK. Gelatinizing oil in water and its removal via bacteria inhabiting the gels. Sci Rep 2017; 7:13975. [PMID: 29070801 PMCID: PMC5656629 DOI: 10.1038/s41598-017-14296-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 10/05/2017] [Indexed: 11/16/2022] Open
Abstract
When crude oil samples were shaken (200 rpm) in seawater samples from the Arabian Gulf at 30 °C, usually oil-gels were produced spontaneously leaving the water quite clear. The gelators could probably be based on cholesteryl derivatives. Microscopic examination of the established gels revealed nanofibrellar structures similar to those described by earlier workers for artificially synthesized gelators. Communities of bacteria including prosthetic and stalked members as well as oil-degrading bacteria were recorded in such gels. Chemical analysis revealed that 88.5% of the oil entrapped by gelation was biodegraded after 40 days at 30 °C. Individual bacterial species isolated from the oil-gels biodegraded in batch cultures between 17.8 and 33.3% of the oil added at time zero in 12 days at 30 °C. Gelation is a promising approach, not only for clean, physical removal of oil spilled in aquatic habitats, as so far suggested, but also in its effective microbiological biodegradation, as the current study revealed.
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Affiliation(s)
- Samir S A Radwan
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, P O Box 5969, Safat, 13060, Kuwait.
| | - Dina M Al-Mailem
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, P O Box 5969, Safat, 13060, Kuwait
| | - Mayada K Kansour
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, P O Box 5969, Safat, 13060, Kuwait
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9
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Al-Mailem DM, Kansour MK, Radwan SS. Capabilities and limitations of DGGE for the analysis of hydrocarbonoclastic prokaryotic communities directly in environmental samples. Microbiologyopen 2017; 6. [PMID: 28516483 PMCID: PMC5635167 DOI: 10.1002/mbo3.495] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 04/06/2017] [Accepted: 04/11/2017] [Indexed: 11/12/2022] Open
Abstract
Prokaryotic communities in pristine and oil-contaminated desert soil, seawater, and hypersaline coastal soil were analyzed using culture-dependent and culture-independent approaches. The former technique was the dilution-plating method. For the latter, total genomic DNA was extracted and the 16S rRNA genes were amplified using a universal bacterial primer pair and primer pairs specific for Actinobacteria, Gammaproteobacteria, and Archaea. The amplicons were resolved using denaturing gradient gel electrophoresis (DGGE) and sequenced, and the sequences were compared to those in GenBank. The plating method offered the advantages of capturing the targeted hydrocarbonoclastic microorganisms, counting them and providing cultures for further study. However, this technique could not capture more than a total of 15 different prokaryotic taxa. Those taxa belonged predominantly to the genera Alcanivorax, Pseudoxanthomonas, Bosea, Halomonas, and Marinobacter. The individual isolates in culture consumed between 19 and 50% of the available crude oil in 10 days. Although the culture-independent approach revealed much more microbial diversity, it was not problem-free. The subdivision primers exhibited satisfactory specificity, but they failed to capture all the available taxa. The universal bacterial primer pair ignored Actinobacteria altogether, although the primer pair specific for Actinobacteria captured many of them, for example, the genera Geodermatophilus, Streptomyces, Mycobacterium, Pontimonas, Rhodococcus, Blastococcus, Kocuria, and many others. Because most researchers worldwide use universal primers for PCR, this finding should be considered critically to avoid misleading interpretations.
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Affiliation(s)
- Dina M Al-Mailem
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Mayada K Kansour
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Samir S Radwan
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
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Al-Mailem DM, Al-Deieg M, Eliyas M, Radwan SS. Biostimulation of indigenous microorganisms for bioremediation of oily hypersaline microcosms from the Arabian Gulf Kuwaiti coasts. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 193:576-583. [PMID: 28262419 DOI: 10.1016/j.jenvman.2017.02.054] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 05/15/2023]
Abstract
Hypersaline soil and water samples were collected in summer and winter from the "sabkha" area at the Kuwaiti shore of the Arabian Gulf. Physicochemical parameters were analyzed, and found suitable for microbial oil-removal. Summer- and winter-microcosms were treated with individual cation (K+, Ca2+, Mg2+, Fe3+) salts, and with animal blood and commercial yeast, as cost-effective vitamin sources. Those microcosms were exposed to the open environment for six winter and six summer months, and analyzed for their hydrocarbonoclastic microorganisms at time zero and in two month intervals. The hydrocarbonoclastic microbial communities in the microcosms consisted of halophilic bacteria and haloarchaea. The constituent bacterial species varied according to the season. Three species, Dietzia kunjamensis, Marinobacter lacisalsi and Halomonas oxialensis consistently occurred both in summer- and winter-samples, but the remaining species were different. On the other hand, the haloarchaeal communities in summer and winter were quite similar, and consisted mainly of Haloferax spp and Halobacterium spp. Treating the microcosms with cations and with vitamin-containing natural products enhanced microbial numbers and oil-removal. The effectiveness of the cations in oil-removal was in the order; Fe3+ (94%) > Ca2+ (89%) > Mg2+ (85%) > K+ (82%). Thus, oily microcosms amended with trivalent and divalent cations lost most of the oil, and those amended with commercial yeast and with animal blood, as vitamin sources, lost 78% and 72% oil, respectively.
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Affiliation(s)
- Dina M Al-Mailem
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait
| | - Maha Al-Deieg
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait
| | - Mohamed Eliyas
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait
| | - Samir S Radwan
- Microbiology Program, Department of Biological Sciences, Faculty of Science, Kuwait University, Kuwait.
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