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1.
World J Microbiol Biotechnol ; 39(3): 84, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36693977

RESUMO

The coexistence of heavy metals (HMs) and petroleum hydrocarbons (PHs) exacerbates ecotoxicity and impair the drivers of eco-functionalities that stimulate essential nutrients for the productivity of the impacted environment. Profiling the bacteria that stem the ecological impact via HMs sequestration and PHs catabolism with nitrogen fixation is imperative to bioremediation of the polluted sites. The sediment of site that was consistently contaminated with industrial wastewaters was analysed for ecological toxicants and the bacterial strains that combined HMs resistance with PHs catabolism in a nitrogen-limiting system were isolated from the sediment and characterized. The geochemistry of the samples revealed the co-occurrence of the above-benchmark concentrations of HMs with the derivatives of hydrocarbons. Notwithstanding, nickel and mercury (with 5% each of the total metal concentrations in the polluted site) exhibited probable effect concentrations on the biota and thus hazardous to the ecosystem. Approx. 31% of the bacterial community, comprising unclassified Planococcaceae, unclassified Bradyrhizobiaceae, Rhodococcus, and Bacillus species, resisted 160 µmol Hg2+ in the nitrogen-limiting system within 24 h post-inoculation. The bacterial strains adopt volatilization, and sometimes in combination with adsorption/bioaccumulation strategies to sequester Hg2+ toxicity while utilizing PHs as sources of carbon and energy. Efficient metabolism of petroleum biomarkers (> 87%) and Hg2+ sequestration (≥ 75% of 40 µmol Hg2+) displayed by the selected bacterial strains portend the potential applicability of the bacilli for biotechnological restoration of the polluted site.


Assuntos
Bacillus , Mercúrio , Metais Pesados , Petróleo , Petróleo/metabolismo , Ecossistema , Metais Pesados/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Bacillus/metabolismo
2.
Arch Microbiol ; 205(1): 50, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36598589

RESUMO

Crude oil pollution is one of the most arduous issues to address, as it is hazardous to both public health and the environment. The discovery of novel biosurfactants-producing fungi and bacteria is in high demand due to their excellent properties and wide range of applications. The aim of this research is to isolate a powerful biosurfactant-producing fungus from the crude oil site near Barauni oil refinery in Bihar, India. Standard protocols were used to collect samples from the site. An integrative taxonomic approach was used, which included morphological, molecular, and phylogenetic analysis. The use of plating samples on Bushnell-Hass (BH) media aided in the isolation of a fungal strain from an enrichment culture. Two fungal strains isolated from contaminated soils, Penicillium citrinum and Paecilomyces variotti, showed potent oil degrading activity in a single culture. For preliminary biosurfactants screening, drop collapse assays, oil spreading, and emulsification activity tests were used. The results showed that the cultures performed well in the screening test and were further evaluated for degradation capacity. Different treatment periods (0, 3, 6, 9, 12, and 15 days) were used to observe degradation in single cultures. A steady drop in pH, an alteration in optical density and an increase in carbon dioxide release showed the ability of fungal strain to degrade the crude oil in a single culture. Fungi mycelia provide a larger surface area for absorption and degradation of the pollutants in contaminated environment. They produce extracellular enzymes to degrade the oil, and at the same time absorb and utilise carbon, allowing them to remove toxic substances from the oil. Thus, they could be candidates for bioremediation of a hydrocarbon-contaminated site.


Assuntos
Eurotiales , Petróleo , Filogenia , Eurotiales/metabolismo , Biodegradação Ambiental , Petróleo/metabolismo , Hidrocarbonetos/metabolismo
3.
J Hazard Mater ; 446: 130656, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603421

RESUMO

Oil spill attenuation in Arctic marine environments depends on oil-degrading bacteria. However, the seasonally harsh conditions in the Arctic such as nutrient limitations and sub-zero temperatures limit the activity even for bacteria capable of hydrocarbon metabolism at low temperatures. Here, we investigated whether the variance between epipelagic (seasonal temperature and inorganic nutrient variations) and mesopelagic zone (stable environmental conditions) could limit the growth of oil-degrading bacteria and lead to lower oil biodegradation rates in the epipelagic than in the mesopelagic zone. Therefore, we deployed absorbents coated with three oil types in a SW-Greenland fjord system at 10-20 m (epipelagic) and 615-650 m (mesopelagic) water depth for one year. During this period we monitored the development and succession of the bacterial biofilms colonizing the oil films by 16S rRNA gene amplicon quantification and sequencing, and the progression of oil biodegradation by gas chromatography - mass spectrometry oil fingerprinting analysis. The removal of hydrocarbons was significantly different, with several polycyclic aromatic hydrocarbons showing longer half-life times in the epipelagic than in the mesopelagic zone. Bacterial community composition and density (16S rRNA genes/ cm2) significantly differed between the two zones, with total bacteria reaching to log-fold higher densities (16S rRNA genes/cm2) in the mesopelagic than epipelagic oil-coated absorbents. Consequently, the environmental conditions in the epipelagic zone limited oil biodegradation performance by limiting bacterial growth.


Assuntos
Poluição por Petróleo , Petróleo , Estuários , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Água do Mar/microbiologia , Hidrocarbonetos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Petróleo/metabolismo
4.
Water Sci Technol ; 87(1): 228-238, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36640034

RESUMO

Bioaugmentation is an effective strategy used to speed up the bioremediation of marine oil spills. In the present study, a highly efficient petroleum degrading bacterium (Pseudomonas aeruginosa ZS1) was applied to the bioremediation of simulated crude oil pollution in different sampling sites in the South China Sea. The metabolic pathways of ZS1 to degrade crude oil, the temporal dynamics of the microbial community response to crude oil contamination, and the biofortification process were investigated. The results showed that the abundance and diversity of the microbial community decreased sharply after the occurrence of crude oil contamination. The best degradation rate of crude oil, which was achieved in the samples from the sampling site N3 after the addition of ZS1 bacteria, was 50.94% at 50 days. C13 alkanes were totally oxidized by ZS1 in the 50 days. The degradation rate of solid n-alkanes (C18-C20) was about 70%. Based on the whole genome sequencing and the metabolites analysis of ZS1, we found that ZS1 degraded n-alkanes through the terminal oxidation pathway and aromatic compounds through the catechol pathway. This study provides data support for further research on biodegradation pathways of crude oil and contributes to the subsequent development of more reasonable bioremediation strategies.


Assuntos
Microbiota , Poluição por Petróleo , Petróleo , Biodegradação Ambiental , Poluição por Petróleo/análise , Alcanos/metabolismo , Petróleo/análise , Bactérias/genética , Bactérias/metabolismo , Redes e Vias Metabólicas , Hidrocarbonetos/metabolismo
5.
Sci Total Environ ; 865: 161112, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36586680

RESUMO

Petroleum hydrocarbon compounds are persistent organic pollutants, which can cause permanent damage to ecosystems due to their biomagnification. Bioremediation of oil is currently the main solution for the remediation of petroleum hydrocarbon pollutants in ecosystems. Despite several lab studies on oil microbial biodegradation efficiency, still there are various challenges for microorganisms to perform efficiently in outside environments. Herewith, investigating efficient biodegradation technologies through discovering new microorganisms, biodegradation pathways modification, and new bioremediations technologies are in great demand. The degradation of petroleum pollutants by microorganisms and the remediation of contaminated soils are achieved through their key enzymes and metabolic pathways. Although, several challenges hinder the effective biodegradation processes such as the toxic environment, long chains and versatility of petroleum hydrocarbons and the existence of the full metabolism pathways in a single microorganism. There are several developed oil biodegradation strategies by microorganisms such as synthetic biology, biofilm, recombinant technology and microbial consortia. Herewith, the application of multi-omics technology to discover oil-contaminated environments microbial communities, synthetic biology, microbial consortia, and other technologies would help improve the efficiency of microbial remediation.


Assuntos
Poluentes Ambientais , Microbiota , Poluição por Petróleo , Petróleo , Poluentes do Solo , Petróleo/metabolismo , Hidrocarbonetos/metabolismo , Biodegradação Ambiental , Poluição por Petróleo/análise , Microbiologia do Solo , Poluentes do Solo/metabolismo
6.
Sci Rep ; 12(1): 21559, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36513758

RESUMO

Adhesive activities of hydrocarbon-oxidizing Rhodococcus bacteria towards solid hydrocarbons, effects of adhesion on biodegradation of these compounds by rhodococcal cells and adhesion mechanisms of Rhodococcus spp. were studied in this work. It was shown that efficiency of Rhodococcus cells' adhesion to solid n-alkanes and polycyclic aromatic hydrocarbons (PAHs) varied from 0.0 to 10.6·106 CFU/cm2. R. erythropolis IEGM 212 and R. opacus IEGM 262 demonstrated the highest (≥ 4.3·106 CFU/cm2) adhesion. The percentage biodegradation of solid hydrocarbons (n-hexacosane and anthracene as model substrates) by Rhodococcus cells was 5 to 60% at a hydrocarbon concentration of 0.2% (w/w) after 9 days and strongly depended on cell adhesive activities towards these compounds (r ≥ 0.71, p < 0.05). No strict correlation between the adhesive activities of rhodococcal cells and physicochemical properties of bacteria and hydrocarbons was detected. Roughness of the cell surface was a definitive factor of Rhodococcus cell adhesion to solid hydrocarbons. Specific appendages with high adhesion force (≥ 0.6 nN) and elastic modulus (≥ 6 MPa) were found on the surface of Rhodococcus cells with high surface roughness. We hypothesized that these appendages participated in the adhesion process.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Rhodococcus , Rhodococcus/metabolismo , Hidrocarbonetos/metabolismo , Biodegradação Ambiental , Alcanos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
7.
Arch Microbiol ; 204(12): 708, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36380118

RESUMO

The bacterial community composition in soil sediments changes with respect to nutrient concentrations and environmental conditions. Reports on the correlation between bacterial populations and inorganic nutrient concentrations in oily sediments are limited. The present time series study reports the prevalence of specific hydrocarbon-degrading bacterial communities in nutrient-treated oily sludge microcosms. The hydrocarbon degradation was maximum at 625 µg nitrogen (N) and 62.5 µg phosphorus (P)/g sludge sediment. The 16S rRNA gene-based DGGE analyses revealed noticeable changes in bacterial community composition with time and levels of nutrient treatment. BLASTn analysis of the 16S rRNA gene clone sequence showed the abundance of γ-Proteobacteria (44%), α-Proteobacteria (16%), ß-Proteobacteria (10%), CFB (4%), and unidentified bacterial clones (26%). The catechol 1,2-dioxygenase (C12O) and catechol 2,3-dioxygenase (C23O) gene clones were affiliated to the genus Sphingomonas, highlighting the vital role of Sphingomonas in aromatic hydrocarbon degradation. The quantity of the 16S rRNA gene and the alkane hydroxylase (alkB) gene reached maximum levels in extended duration microcosms treated with 625 µg N and 62.5 µg P/g sludge sediment. In contrast, the C12O gene reached its highest abundance at a low N concentration.


Assuntos
Petróleo , Petróleo/metabolismo , Esgotos/microbiologia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Biodegradação Ambiental , Prevalência , Hidrocarbonetos/metabolismo , Bactérias , Nutrientes/análise , Filogenia
8.
Arch Microbiol ; 204(12): 701, 2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36370212

RESUMO

Waxy crude oil is a problem to the oil and gas industry because wax deposition in pipelines reduces the quality of the crude oil. Currently, the industry uses chemicals to solve the problem but it is not environmentally friendly. As an alternative, the biodegradation approach is one of the options. Previously eleven thermophilic bacteria were isolated and exhibited high ability to degrade hydrocarbon up to 70% of waxy crude oil. However, despite the successful study on these single bacteria strains, it is believed that biodegradation of paraffin wax requires more than a single species. Five consortia were developed based on the biodegradation efficiency of 11 bacterial strains. Consortium 3 showed the highest biodegradation (77.77%) with more long-chain alkane degraded throughout the incubation compared to other consortia. Enhancement of hydrocarbon degradation was observed for all consortia especially in long chain alkane (C18-C40). Consortium 3 exhibited higher alkane monooxygenase, alcohol dehydrogenase, lipase, and esterase activities. Moreover, the dominant bacteria in the consortia were determined by denaturing gradient gel electrophoresis (DGGE), which showed the domination of genera Geobacillus, Parageobacillus, and Anoxybacillus. It can be concluded that the bacterial consortia showed higher biodegradation and improved degrading more long-chain hydrocarbon compared to a single isolate.


Assuntos
Petróleo , Petróleo/metabolismo , Ceras/metabolismo , Hidrocarbonetos/metabolismo , Biodegradação Ambiental , Bactérias/genética , Bactérias/metabolismo , Alcanos/metabolismo
9.
Sci Rep ; 12(1): 19770, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396722

RESUMO

Adsorption of old-aged petroleum hydrocarbons to the soil solid phase, which causes biosurfactant loss of performance, is among the limiting factors for the remediation of the saline-sodic soils contaminated with petroleum. Therefore, to find a functional biosurfactant in oil-contaminated saline-sodic soils, the efficiency of 39 bacteria isolated from petroleum-contaminated soils was evaluated. The strains were cultured in the Bushnell-Haas medium, and the produced biosurfactants and bioemulsifiers in this medium were extracted using chloroform/methanol and ethyl acetate extraction methods, respectively. Their partial purification was performed by column chromatography, and eventually, their performance in releasing TPH from the contaminated soil was evaluated. The soil test results revealed that the highest TPH releases due to the effects of the biosurfactants and bioemulsifier produced from SHA302, SH21, and SH72 isolates were 42.4% ± 0.2, 21.6% ± 0.15 and 24.3% ± 0.91, respectively. Based on the 16S rRNA gene sequence, the SHA302 strain showed 93.98% phylogenetic similarity with Bacillus pumilus strain ATCC 7061. The Fourier transform infrared spectroscopy and thin-layer chromatography results proved that the biosurfactants produced by isolates SHA302, SH21 and SH72 showed lipopeptide, glycolipoprotein and glycoprotein natures, respectively. The performance of the biosurfactant produced by SHA302 isolate indicated that it could be used as a good candidate for releasing TPH from saline-sodic soils with old contamination and facilitating the degradation of hydrocarbons.


Assuntos
Bacillus , Petróleo , Poluentes do Solo , Petróleo/metabolismo , Solo/química , Bacillus/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Filogenia , Biodegradação Ambiental , Poluentes do Solo/metabolismo , Tensoativos/química , Hidrocarbonetos/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-36429785

RESUMO

To improve the environmental sustainability of cleanup activities of contaminated sites there is a need to develop technologies that minimize soil and habitat disturbances. Cleanup technologies, such as bioremediation, are based on biological products and processes, and they are important for the future of our planet. We studied the potential of γ-poly glutamic acid (PGA) as a natural component of biofilm produced by Bacillus sp. to be used for the decomposition of petroleum products, such as heavy naphtha (N), lubricating oil (O), and grease (G). The study aimed to assess the impact of the use of different concentrations of PGA on the degradation process of various fractions of petroleum hydrocarbons (PH) and its effect on bacterial population growth in harsh conditions of PH contamination. In laboratory conditions, four treatments of PGA with each of the petroleum products (N, O, and G) were tested: PGA0 (reference), PGA1 (1% PGA), PGA1B (1% PGA with Bacillus&nbsp;licheniformis), and PGA10 (10% PGA). After 7, 28, 56, and 112 days of the experiment, the percentage yield extraction, hydrocarbon mass loss, geochemical ratios, pH, electrical conductivity, and microorganisms survival were determined. We observed an increase in PH removal, reflected as a higher amount of extraction yield (growing with time and reaching about 11% in G) and loss of hydrocarbon mass (about 4% in O and G) in all treatments of the PGA compared to the reference. The positive degradation impact was intensive until around day 60. The PH removal stimulation by PGA was also reflected by changes in the values of geochemical ratios, which indicated that the highest rate of degradation was at the initial stage of the process. In general, for the stimulation of PH removal, using a lower (1%) concentration of PGA resulted in better performance than a higher concentration (10%). The PH removal facilitated by PGA is related to the anionic homopoliamid structure of the molecule and its action as a surfactant, which leads to the formation of micelles and the gradual release of PH absorbed in the zeolite carrier. Moreover, the protective properties of PGA against the extinction of bacteria under high concentrations of PH were identified. Generally, the γ-PGA biopolymer helps to degrade the hydrocarbon pollutants and stabilize the environment suitable for microbial degraders development.


Assuntos
Petróleo , Ácido Poliglutâmico , Ácido Poliglutâmico/química , Prostaglandinas A , Hidrocarbonetos/metabolismo
11.
J Basic Microbiol ; 62(12): 1429-1439, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36285670

RESUMO

A consortium isolated from the Persian Gulf is evaluated for its ability to bioremediate petroleum-contaminated soils. The soil sample was collected from oil fields of South Western Iran. The crude oil concentrations were set to 1000-10,000 mg/kg, and the sodium chloride concentration was set to 0.5%, 1%, 1.5%, 2%, and 2.5%. Operational parameters including volume (2-20 ml) and soil moisture (25%, 50%, and 100%) were studied consecutively according to one factor at the time of experimental design. A total number of eight different isolates capable of degrading crude oil were isolated from hydrocarbon-contaminated sites (KL1-KL8). The removal efficiency of Total petroleom hydrocarbons (TPH) with an initial concentration of 1000 mg/kg for numbers of bacterial cells per gram soil of 2, 10, and 20 CFU/g was 20.9%, 45%, and 60%, respectively. The removal efficiency of TPHs (initial concentration of 1000 mg/kg) at the end of fifth week for salinity amounts of 0.5%, 1%, 1.5%, 2%, and 2.5% was 10.87%, 22.4%, 25.7%, 68.6%, and 60.5%, respectively. The TPHs biodegradation efficiencies at different soil/water ratios of 25%, 50%, and 100% (slurry) were 12%, 28.7%, and 60.8%, respectively. In sunflowers, there was no statistically significant difference in seed germination for different levels of soil pollution (p > 0.05). The results of the current work suggest that this process is a viable and efficient method for remediating contaminated sites. To enhance the removal results in real soil, a scale-up study should also be conducted.


Assuntos
Bacillus , Petróleo , Poluentes do Solo , Petróleo/metabolismo , Biodegradação Ambiental , Bacillus/metabolismo , Microbiologia do Solo , Oceano Índico , Poluentes do Solo/metabolismo , Hidrocarbonetos/metabolismo , Solo
12.
Molecules ; 27(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36234987

RESUMO

Currently, the bioremediation of petroleum hydrocarbons employs microbial biosurfactants because of their public acceptability, biological safety, and low cost. These organisms can degrade or detoxify organic-contaminated areas, such as marine ecosystems. The current study aimed to test the oil-biodegradation ability of the fungus Drechslera spicifera, which was isolated from contaminated soil samples in Riyadh, Saudi Arabia. We used hydrocarbon tolerance, scanning electron microscopy, DCPIP, drop-collapse, emulsification activity, recovery of biosurfactants, and germination assays to assess the biodegradation characteristics of the D. spicifera against kerosene, crude, diesel, used, and mixed oils. The results of DCPIP show that the highest oxidation (0.736 a.u.) was induced by crude oil on the 15th day. In contrast, kerosene and used oil had the highest measurements in emulsification activity and drop-collapse assays, respectively. Meanwhile, crude and used oils produced the highest amounts of biosurfactants through acid precipitation and solvent extraction assays. Furthermore, the biosurfactants stimulated the germination of tomato seeds by more than 50% compared to the control. These findings highlight the biodegradation ability of D. spicifera, which has been proven in the use of petroleum oils as the sole source of carbon. That might encourage further research to demonstrate its application in the cleaning of large, contaminated areas.


Assuntos
Petróleo , Poluentes do Solo , Biodegradação Ambiental , Carbono , Ecossistema , Hidrocarbonetos/metabolismo , Querosene , Óleos , Petróleo/metabolismo , Arábia Saudita , Solo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Solventes
13.
BMC Genomics ; 23(1): 690, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36203131

RESUMO

BACKGROUND: Hydrocarbons (HCs) are organic compounds composed solely of carbon and hydrogen that are mainly accumulated in oil reservoirs. As the introduction of all classes of hydrocarbons including crude oil and oil products into the environment has increased significantly, oil pollution has become a global ecological problem. However, our perception of pathways for biotic degradation of major HCs and key enzymes in these bioconversion processes has mainly been based on cultured microbes and is biased by uneven taxonomic representation. Here we used Annotree to provide a gene-centric view of the aerobic degradation ability of aliphatic and aromatic HCs in 23,446 genomes from 123 bacterial and 14 archaeal phyla.  RESULTS: Apart from the widespread genetic potential for HC degradation in Proteobacteria, Actinobacteriota, Bacteroidota, and Firmicutes, genomes from an additional 18 bacterial and 3 archaeal phyla also hosted key HC degrading enzymes. Among these, such degradation potential has not been previously reported for representatives in the phyla UBA8248, Tectomicrobia, SAR324, and Eremiobacterota. Genomes containing whole pathways for complete degradation of HCs were only detected in Proteobacteria and Actinobacteriota. Except for several members of Crenarchaeota, Halobacterota, and Nanoarchaeota that have tmoA, ladA, and alkB/M key genes, respectively, representatives of archaeal genomes made a small contribution to HC degradation. None of the screened archaeal genomes coded for complete HC degradation pathways studied here; however, they contribute significantly to peripheral routes of HC degradation with bacteria. CONCLUSION: Phylogeny reconstruction showed that the reservoir of key aerobic hydrocarbon-degrading enzymes in Bacteria and Archaea undergoes extensive diversification via gene duplication and horizontal gene transfer. This diversification could potentially enable microbes to rapidly adapt to novel and manufactured HCs that reach the environment.


Assuntos
Archaea , Petróleo , Bactérias , Biodegradação Ambiental , Carbono/metabolismo , Hidrocarbonetos/metabolismo , Hidrogênio/metabolismo , Petróleo/metabolismo , Filogenia
14.
Microbiology (Reading) ; 168(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36190831

RESUMO

As sequencing technology improves and the cost of metagenome sequencing decreases, the number of sequenced environments increases. These metagenomes provide a wealth of data in the form of annotated and unannotated genes. The role of multidrug resistance efflux pumps (MDREPs) is the removal of antibiotics, biocides and toxic metabolites created during aromatic hydrocarbon metabolism. Due to their naturally occurring role in hydrocarbon metabolism and their role in biocide tolerance, MDREP genes are of particular importance for the protection of pipeline assets. However, the heterogeneity of MDREP genes creates a challenge during annotation and detection. Here we use a selection of primers designed to target MDREPs in six pure species and apply them to publicly available metagenomes associated with oil and gas environments. Using in silico PCR with relaxed primer binding conditions we probed the metagenomes of a shale reservoir, a heavy oil tailings pond, a civil wastewater treatment, two marine sediments exposed to hydrocarbons following the Deepwater Horizon oil spill and a non-exposed marine sediment to assess the presence and abundance of MDREP genes. Through relaxed primer binding conditions during in silico PCR, the prevalence of MDREPs was determined. The percentage of nucleotide sequences identified by the MDREP primers was partially augmented by exposure to hydrocarbons in marine sediment and in shale reservoir compared to hydrocarbon-free marine sediments while tailings ponds and wastewater had the highest percentages. We believe this approach lays the groundwork for a supervised method of identifying poorly conserved genes within metagenomes.


Assuntos
Desinfetantes , Hidrocarbonetos Aromáticos , Antibacterianos , Resistência a Múltiplos Medicamentos , Sedimentos Geológicos , Hidrocarbonetos/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-36141622

RESUMO

Continuous bioreactors for petroleum degradation and the effect factors of these bioreactors have rarely been mentioned in studies. In addition, indigenous bacteria living in seawater could influence the performance of continuous bioreactors with respect to petroleum degradation in practice. In this paper, a bioreactor fitted with immobilized petroleum-degrading bacteria beads was designed for further research. The results indicated that the diesel degradation rate of the bioreactor could remain above 50% over 27 days, while degradation performance decreased with bioremediation time. Intriguingly, the diameters of immobilized petroleum-degrading bacteria beads were reduced by 32.49% after 45 days remediation compared with the initial size of the immobilized petroleum-degrading bacteria beads. Change in immobilized petroleum-degrading bacteria beads was considered to correlate remarkably with reduced degradation efficiency. Therefore, this paper will be helpful for further study and improvement of bioreactors in the practical context of oil-spill accident recovery.


Assuntos
Microbiota , Poluição por Petróleo , Petróleo , Bactérias/metabolismo , Biodegradação Ambiental , Reatores Biológicos , Hidrocarbonetos/metabolismo , Petróleo/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-36142106

RESUMO

The microbial remediation technology had great potential and attracted attention to total petroleum hydrocarbon pollution (TPH) remediation, but its efficiency is limited by its application in the field. In this study, a new TPH-degrading strain, TDYN1, was isolated from contaminated oil soil in Dagang Oilfield in Tianjin, China, and identified as Falsochrobactrum sp. by 16S rRNA sequence analysis. The physiological characterization of the isolate was observed. The orthogonal experiment was carried out for the optimum degradation conditions to improve its biodegradation efficiency. The strain was the gram-stain-negative, short rod-shaped, non-spore-forming, designated Falsochrobactrum tianjinense sp. nov (strain TDYN1); it had 3.51 Mb, and the DNA G + C content of the strain was 56.0%. The degradation rate of TDYN1 was 69.95% after 7 days of culture in optimal degradation conditions (temperature = 30 °C, pH = 8, salinity = 10 g L-1, petroleum concentration = 1 g L-1, and the inoculation dose of strain TDYN1 = 6%) and also reached more than 30% under other relatively extreme conditions. It suggested that the TDYN1 has great potential for TPH remediation in the soils of North China.


Assuntos
Petróleo , Poluentes do Solo , Bactérias/genética , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Petróleo/análise , Filogenia , RNA Ribossômico 16S/genética , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise
17.
J Appl Microbiol ; 133(6): 3296-3306, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36106420

RESUMO

AIM: Biodegradation is a cost-effective and eco-friendly treatment for oil-contaminated materials using microorganisms. Bacteria and fungi can degrade petroleum by using it as an energy source and this may provide an enormous scope to remediate soils contaminated with petroleum and oil. This study aimed to assess the biodegradation of petroleum hydrocarbons by certain Cladosporium species. METHODS AND RESULTS: By using traditional and spectroscopic assessment analysis, qualitative screening was carried out using Cladosporium spores isolated from air and cultured on mineral salt medium supplemented with petroleum hydrocarbon as the sole carbon source, followed by quantitative assessment using gas chromatography-mass spectroscopy. Nineteen Cladosporium strains from a total of 212 isolates exhibited remarkable capability to degrade petroleum hydrocarbon, representing four species (C. herbarum, C. macrocarpum, C. sphaerospermum, and C. cladosporioides). The results were expressed in terms of biodegradation percentage and optical density of hydrocarbon using a standard calibration curve. The highest reduction of petroleum hydrocarbon was observed with five Cladosporium strains belonging to two species (C. sphaerospermum and C. cladosporioides). CONCLUSION: This study succeeded in isolating several Cladosporium strains (from the air) with a high ability to degrade crude oil that can be used as biological agents to control petroleum pollution in soils and seas. The addition of a surfactant (Tween 80) enhanced the degradation of crude oil reaching a final concentration of 0.4%. Based on these results, the present study could indicate some unique prospects in the field of bioremediation and biodegradation of petroleum-contaminated soil. SIGNIFICANCE AND IMPACT OF STUDY: This study gives unique prospects in the field of bioremediation and biodegradation of petroleum-contaminated soil.


Assuntos
Petróleo , Poluentes do Solo , Petróleo/metabolismo , Biodegradação Ambiental , Cladosporium/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Hidrocarbonetos/metabolismo , Solo/química
18.
Environ Pollut ; 313: 120164, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36113645

RESUMO

Bioremediation of real-time petroleum refining industry oily waste (PRIOW) is a major challenge due to the poor emulsification potential and oil sludge disintegration efficiency of conventional bioamphiphile molecules. The present study was focused on the design of a covalently engineered supramolecular bioamphiphile complex (SUBC) rich in hydrophobic amino acids for proficient emulsification of hydrocarbons followed by the concomitant degradation of total petroleum hydrocarbons (TPH) in PRIOW using the hydrocarbonoclastic microbial bio-formulation system. The synthesis of SUBC was carried out by pH regulated microbial biosynthesis process and the yield was obtained to be 450.8 mg/g of petroleum oil sludge. The FT-IR and XPS analyses of SUBC revealed the anchoring of hydrophilic moieties of monomeric bioamphiphilic molecules, resulting in the formation of SUBC via covalent interaction. The SUBC was found to be lipoprotein in nature. The maximum loading capacity of SUBC onto surface modified rice hull (SMRH) was achieved to be 45.25 mg/g SMRH at the optimized conditions using RSM-CCD design. The SUBC anchored SMRH was confirmed using SEM, FT-IR, XRD and TGA analyses. The adsorption isotherm models of SUBC onto SMRH were performed. The integrated approach of SUBC-SMRH and hydrocarbonoclastic microbial bio-formulation system, emulsified oil from PRIOW by 92.86 ± 2.26% within 24 h and degraded TPH by 89.25 ± 1.75% within 4 days at the optimum dosage ratio of SUBC-SMRH (0.25 g): PRIOW (1 g): mass of microbial-assisted biocarrier material (0.05 g). The TPH degradation was confirmed by SARA fractional analysis, FT-IR, 1H NMR and GC-MS analyses. The study suggested that the application of covalently engineered SUBC has resulted in the accelerated degradation of real-time PRIOW in a very short duration without any secondary sludge generation. Thus, the SUBC integrated approach can be considered to effectively manage the hydrocarbon contaminants from petroleum refining industries under optimal conditions.


Assuntos
Petróleo , Aminoácidos , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Resíduos Industriais , Petróleo/análise , Esgotos , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Chemosphere ; 308(Pt 3): 136446, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36113659

RESUMO

With the crude oil exploration activities in the Shanbei oilfield of China, the risk of soil contamination with crude oil spills has become a major concern. This study aimed at assessing the bioremediation potential of the petroleum polluted soils by investigating the expression of key functional genes decoding alkane and aromatic component degradation using an array of primers and real-time quantitative PCR (qPCR), and the functional microbiomes were determined using a combination of substrate-induced metabolic responses and high throughput sequencing. The results showed that the species that were more inclined to degrade aliphatic fraction of crude oil included Acinetobacter, Stenotrophomonas, Neorhizobium and Olivebacter. And Pseudomonas genus was a highly specific keystone species with the potential to degrade PAH fraction. Both aliphatic and PAH-degrading genes were upregulated when the soil petroleum contents were less than 10,000 mg/kg but downregulated when the oil contents were over 10,000 mg/kg. Bioremediation potential could be feasible for medium pollution with petroleum contents of less than 10,000 mg/kg. Optimization of the niche of Acinetobacter, Stenotrophomonas, Pseudomonas, Neorhizobium and Olivebacter species was beneficial to the biodegradation of refractory hydrocarbon components in the Shanbei plateau oilfield.


Assuntos
Poluição por Petróleo , Petróleo , Poluentes do Solo , Alcanos , Biodegradação Ambiental , Sequenciamento de Nucleotídeos em Larga Escala , Hidrocarbonetos/metabolismo , Campos de Petróleo e Gás , Petróleo/análise , Poluição por Petróleo/análise , Solo , Microbiologia do Solo , Poluentes do Solo/análise
20.
Microbiol Res ; 265: 127184, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36115172

RESUMO

Hydrocarbon contamination is continuing to be a serious environmental problem because of their toxicity. Hydrocarbon components have been known to be carcinogens and neurotoxic organic pollutants. The physical and chemical methods of petroleum removal have become ineffective and also are very costly. Therefore, bioremediation is considered the promising technology for the treatment of these contaminated sites since it is cost-effective and will lead to complete mineralization.The current study also concentrates on bioremediation of petroleum products by bacterium isolated from petroleum hydrocarbon contaminated soil. The current work shows that bacterial strains obtained from a petroleum hydrocarbon contaminated environment may degrade petroleum compounds. Two strains Bacillus licheniformis ARMP2 and Pseudomonas aeruginosa ARMP8 were identified as petroleum-degrading bacteria of the isolated bacterial colonies. The best growth conditions for the ARMP2 strain were determined to be pH 9, temperature 29 °C with sodium nitrate as its nitrogen source, whereas for the ARMP8 strain the optimal growth was found at pH 7, temperature 39 °C, and ammonium chloride as the nitrogen source. Both strains were shown to be effective at degrading petroleum chemicals confirmed by GCMS. Overall petroleum product degradation efficiency of the strains ARMP2 and ARMP8 was about 88 % and 73 % respectively in 48 h.The strains Bacillus licheniformis ARMP2 and Pseudomonas aeruginosa ARMP8 were shown to be effective at degrading petroleum compounds in the current study. Even greater results might be obtained if the organisms were utilised in consortia or the degradation time period was extended.


Assuntos
Petróleo , Poluentes do Solo , Cloreto de Amônio/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental , Carcinógenos/metabolismo , Hidrocarbonetos/metabolismo , Hidrocarbonetos/toxicidade , Nitrogênio/metabolismo , Petróleo/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Solo/química , Microbiologia do Solo , Poluentes do Solo/metabolismo
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