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In this study, variations in the levels of oil hydrocarbons and polycyclic aromatic hydrocarbons (PAHs), which are persistent organic pollutants generated by human activities, were assessed in the bottom sediments of the Caspian Sea (Russia) sampled from 2012 to 2021. The samples were analyzed for their chemical composition. The concentrations of the identified compounds responsible for hydrocarbon pollution were established. The quantitative results of the industrial environmental monitoring in the Russian sector of the Caspian Sea for subsoil use were also reviewed and processed by standard statistical methods. It was revealed that ΣPAH concentrations in the Northern and Middle Caspian Sea regions vary from analytical zero to 186.7 µg/kg and from zero to 467.8 µg/kg, respectively. The scale of oil pollution in these two regions was found to be determined by the following PAHs: phenanthrene, acenaphthene, and naphthalene. The origin of the listed PAHs provides vital information on the main sources of pollution of the Caspian Sea bottom sediments with hazardous organic substances. Based on the obtained data, the areas with background PAH pollution of the bottom sediments and those with the characteristic PAH of mainly natural and pyrogenic origin were located.

Natural and technical phytoremediation approaches were compared for their efficacy in decontaminating oil-polluted soil. We examined 20 oil-contaminated sites of 800 to 12,000 m2 each, with different contamination types (fresh or aged) and levels (4.2–27.4 g/kg). The study was conducted on a field scale in the industrial and adjacent areas of a petroleum refinery. Technical remediation with alfalfa (Medicago sativa L.), ryegrass (Lolium perenne L.), nitrogen fertilizer, and soil agrotechnical treatment was used to clean up 10 sites contaminated by oil hydrocarbons (average concentration, 13.7 g/kg). In technical phytoremediation, the per-year decontamination of soil was as high as 72–90%, whereas in natural phytoremediation (natural attenuation with native vegetation) at 10 other oil-contaminated sites, per-year decontamination was as high as that only after 5 years. Rhizodegradation is supposed as the principal mechanisms of both phytoremediation approaches. [ABSTRACT FROM AUTHOR]

This review presents a comprehensive summary of the latest research in the field of bioremediation with filamentous fungi. The main focus is on the issue of recent progress in remediation of pharmaceutical compounds, heavy metal treatment and oil hydrocarbons mycoremediation that are usually insufficiently represented in other reviews. It encompasses a variety of cellular mechanisms involved in bioremediation used by filamentous fungi, including bio-adsorption, bio-surfactant production, bio-mineralization, bio-precipitation, as well as extracellular and intracellular enzymatic processes. Processes for wastewater treatment accomplished through physical, biological, and chemical processes are briefly described. The species diversity of filamentous fungi used in pollutant removal, including widely studied species of Aspergillus, Penicillium, Fusarium, Verticillium, Phanerochaete and other species of Basidiomycota and Zygomycota are summarized. The removal efficiency of filamentous fungi and time of elimination of a wide variety of pollutant compounds and their easy handling make them excellent tools for the bioremediation of emerging contaminants. Various types of beneficial byproducts made by filamentous fungi, such as raw material for feed and food production, chitosan, ethanol, lignocellulolytic enzymes, organic acids, as well as nanoparticles, are discussed. Finally, challenges faced, future prospects, and how innovative technologies can be used to further exploit and enhance the abilities of fungi in wastewater remediation, are mentioned.

A biopreparation consisting of the cells of Azospirillum brasilense strain SR80 immobilized on wood biochar was characterized. Sorption of oil by biochar and its colonization by Azospirillum were studied in liquid medium. Oil sorption by biochar was found to decrease in the presence of microbial cells. Within the 22–45°C temperature range, the highest oil biodegradation efficiency by biochar-immobilized and suspended cells was observed at 22 and 38°C, respectively. These data were confirmed by soil experiments. Under conditions of a laboratory pot experiments, the biochar-immobilized microbial culture in combination with two plants (Sorghum bicolor and Medicago falcata) exhibited the highest oil removal efficiency compared to other variants. The introduced strain A. brasilense SR80 exhibited high survival in tilled soil during two-month incubation, as was confirmed by molecular biological assays. Suspended Azospirillum cells exhibited higher oil-oxidizing activity than the immobilized ones in a field experiment under real-life conditions of a hot dry summer. The present work shows high dependence of bioremediation technologies upon environmental factors and indicates the need for thorough investigation of the processes involved. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the present study was to evaluate the toxicity and biodegradation potential of oil hydrocarbons contaminated soil samples obtained from different depths at an oil refinery station area. An approach involving chemical, microbiological, respirometry and ecotoxicity assessment of soil polluted by oil hydrocarbons was adopted, in order to determine the biodegradability of pollutants and ecotoxicological effects of natural attenuation strategy. Methods: The ecotoxicity of soil samples was evaluated using an ostracod test kit and a seed germination test. The results of the phytotoxicity assay were expressed as a percentage of seedling emergence and as the relative yield of fresh and dry biomass compared to control plants. The intrinsic biodegradation potential of the contaminated soil was examined using a Micro-Oxymax respirometer. Intrinsic biodegradation rates were estimated from the slopes of linear regressions curves plotted for cumulative O2 uptake. The obtained values were then entered in the mass balance equation for the stoichiometric reaction of hydrocarbon decomposition and converted per kg of soil per day. Results: Although the tested contaminants were biodegradable in the respirometric assay, they were slightly to moderately toxic to plants and extremely toxic to ostracods. The noxious effects raised with the increased concentration of contaminants. The monocotyledonous oat was more tolerant to higher concentrations of oil hydrocarbons than the other test plants, indicating its greater suitability for soil reclamation purposes. Conclusion: By assessing phytotoxicity and effect on ostracod mortality and progress of soil self-decontamination process, proper approach of reclamation of demoted area can be provided. [ABSTRACT FROM AUTHOR]

Natural and technical phytoremediation approaches were compared for their efficacy in decontaminating oil-polluted soil. We examined 20 oil-contaminated sites of 800 to 12,000 m2 each, with different contamination types (fresh or aged) and levels (4.2–27.4 g/kg). The study was conducted on a field scale in the industrial and adjacent areas of a petroleum refinery. Technical remediation with alfalfa (Medicago sativa L.), ryegrass (Lolium perenne L.), nitrogen fertilizer, and soil agrotechnical treatment was used to clean up 10 sites contaminated by oil hydrocarbons (average concentration, 13.7 g/kg). In technical phytoremediation, the per-year decontamination of soil was as high as 72–90%, whereas in natural phytoremediation (natural attenuation with native vegetation) at 10 other oil-contaminated sites, per-year decontamination was as high as that only after 5 years. Rhizodegradation is supposed as the principal mechanisms of both phytoremediation approaches.

The hydrocarbon-oxidizing potential, ability to synthesize biosurfactants, and resistance to ecologically significant factors were studied for the following previously isolated degrader strains: Acinetobacter seifertii WS-1, Pseudomonas extremaustralis WS-1, Dietzia maris 367-2, Rhodococcus qingshengii 367-6, and Gordonia cholesterolivorans S12. The studied strains were able to act as hydrocarbon degraders at moderate (25–37°C) and low (6–10°C) temperatures, within broad ranges of pH (4.0–11.5) and salinity (0–9%). Apart from individual n-alkanes, they efficiently degraded oil (85–91% of the aliphatic fraction after 5 days). Depending on the culture, biodegradation varied from 96 to 100% for С10–С29n-alkanes and from 26 to 47% for С14–С20iso-alkanes. The rates of hydrocarbon consumption and substrate preferences of the strains were studied using a model mixture of С10–С33n-alkanes. Metabolism of multiply branched alkanes, 2,2,4,4,6,8,8-heptamethylnonane (HMN) and squalane (С30Н62, 2,6,10,15,19,23-hexamethyltetracosane), which are usually resistant to biodegradation, was activated in the presence of n-alkanes, while iso-alkanes were consumed simultaneously with n-alkanes, albeit at a lower rate. The rate of squalane oxidation decreased after complete elimination of n-alkanes, while active HMN biodegradation continued. The strains utilized 48–68% squalane in 6 days and 28–82% HMN in 4 days. While HMN could not be used as the sole carbon and energy source by the studied strains, prolonged cultivation (30 days) with squalane resulted in a drastic decrease of surface and interfacial tensions, poor bacterial growth, and consumption of up to 15% of the hydrocarbon. All studied degrader strains were shown to produce surface-active compounds (SAC). Hydrophobic substrates (liquid paraffins, squalane, and olive oil) induced production of SAC with a pronounced surfactant activity, which decreased the interfacial and surface tensions to their minimal values of 2.0 and 27.2 mN/m, respectively, while water-soluble carbon sources (ethanol, benzoate, and phenol) induced production of emulsifying agents. Emulsifying activity was found in some strains, only on certain substrates, and did not exceed 50%. High metabolic and adaptive potential of the studied strains may be used for bioremediation of oil-contaminated objects. [ABSTRACT FROM AUTHOR]

Aim. Currently, oil pollution remains one of the primary pollutants of the marine environment. This is especially true for the Black Sea and Azov Sea which experience significant anthropogenic pressure. The study presents the results of two-year monitoring studies of the content of oil hydrocarbons in the surface and bottom horizons of the coastal waters of the Azov-Black Sea regions of Russia.Materials and Methods. The determination of oil hydrocarbons was conducted by infrared spectrometry using a FSM-1201 Fourier spectrophotometer with preliminary transmission of the extracts through a chromatographic column with aluminum oxide. The work was carried out as part of five scientific expeditions (93th, 96th, 100th, 102nd and 105th) of the research vessel, Professor Vodyanitsky, in 2017 and 2018.Results. The general environmental status for this pollutant is characterized as stable, despite in some cases being 3 to 4 times in excess of established standards (MPC). Separate foci of localized oil pollution have been identified and vulnerable areas of the sea coast of southern Russia have been identified. An excess content of petroleum hydrocarbons in the surface layer compared to the bottom layer was noted, which indicates a surface path of entry of petroleum products into sea water.Conclusion. Currently, the coastal waters of the western part of Crimea are most affected by oil, primarily associated with the runoff of European rivers and the peculiarities of the marine hydrological regime, including the Kerch Strait, an area of heavy shipping traffic. The Caucasian coast is less affected by oil pollution than the Crimean. Despite the fact that currently the content of oil hydrocarbons in sea water is far from the quantities dangerous to humans and aquatic organisms, monitoring of this indicator is vital due to the increasing anthropogenic pressure on the recreational zones of the Crimean and Caucasian coasts of the Russian Federation.

The presence of oil hydrocarbons and salts in soils has as consequence the poor growth of plants due to the low availability of nutrients caused by unappropriate water regime, increased soil toxicity and the deterioration of soil structure. The present research has as main purpose the improvement of the bean plants (cultivar UNIDOR) growth and to stimulate microbial activity in rhizosphere using various natural stimulators and fertilizers (AMALGEROL,VERMIPLANT, POCO, IGUANA and FORMULEX) in greenhouse experiments on oil-polluted soil from Icoana farm, Olt county. The total counts of microorganisms (heterotrophic aerobic bacteria and filamentous fungi) were estimated by dilution plate method. The global microbial activity was measured as soil respiration by substrate-induced respiration method. Total bean plants biomass accumulation significantly increased under the influence of natural stimulators and fertilizers added (excepting IGUANA) when compared to untreated control. The best results were recorded for VERMIPLANT. Natural products induced activation of physiological activities of soil microbiota reflected in increased values of CO2 released by respiration, lower levels of colonization with phytopathogenic species, the domination of fluorescent pseudomonads, actinomycetes and cellulolytic fungi, too. The particular aspect of paper circular chromatograms reflected qualitative differences between rhizosphere soils determined by the effect of treatments with natural stimulators and fertilizers.

The mathematical modeling of hydrocracking reaction of petroleum fractions was carried out considering a pseudohomogeneous phase. The discrete description was used to represent the kinetic of the reactions. One to 6 lumps of pseudocompounds with different reaction routes were used. Data from the oil hydrocarbon hydrocracking of literature were used to obtain the mathematical model parameters. Modeling more than one group or lump was done by automatic successive approach solving the system of equations starting with one lump, then two, then three, and so on, checking that the material balance is satisfied in each case. Findings showed concordance between the models and the experimental data, highlighting the use of six lumps, from whose description it is possible to determine the composition of the hydrocracking products in a detailed and reliable way. [ABSTRACT FROM AUTHOR]

Purpose: Crude oil and oil products are the most widespread environmental pollutants. The most efficient bioremediation is performed by using specific oil-degrading strains. Our objectives were to assess the role of soil bacteria, belonging to the following genera Arthrobacter, Microbacterium, Rhodococcus, Gordonia, and Acinetobacter in reduction of toxicity of environmental pollutants. Bacteria with different versatility were chosen: isolates from aromatic compounds or crude oil-contaminated soils and common representatives of the soil microflora. Materials and methods: In this work, crude oil from the field Aschisay (Kazakhstan) of the following composition: alkanes 78%, naphthenes 6.7%, arenes 3.7%, and other compounds 11.6% was used as carbon source. To investigate the metabolic activity of microorganisms, they were cultured in flasks for 10 days under different conditions (variations in pH range, temperature, salinity, carbon source). Infrared spectrophotometry method was employed to determine the residual oil content after cultivation of bacteria. The ability of bacteria to produce biosurfactants was assessed by measuring surface tension and emulsifying activity (the Francey et al. method); localization of biosurfactants was detected. Results and discussion: Forty-six strains from oil-spilled soils were isolated, with seven of these isolates showing the high degradation ability. Analysis of 16S-RNA gene sequences assigns these cultures to the genus Rhodococcus. Their degradation activity was then compared with the one of two rhodococci isolated from soil contaminated with chloroaromatics. The strains under study degraded crude oil, diesel fuel, and phenol; some of them destroyed benzene and naphthalene. The most active strains utilized up to 55–59% of crude oil hydrocarbons. The behavior of strains in the presence of petroleum components (benzene, toluene, nonane, decane, hexadecane) revealed bacterial persistence under severe conditions. Bacteria proved to be more sensitive to aromatic solvents than to aliphatic hydrocarbons. Most of the strains produced biosurfactants when grown on hydrophobic substrates. Conclusions: The obtained results show that bacteria highly adapted to oil contaminations play an important role in the biodegradation of recalcitrant pollutants. Such strains may serve as the basis of bioaugmentation approach for soil remediation in sites with high contamination degree. Furthermore, this study highlights a significant role of common representatives of soil microflora in reducing pollution level in the soil owing to various, however, not necessary high destructive activities of soil strains. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Exposure to oil hydrocarbons can impact food web structure. • We applied an uncertainty analysis to the Gulf of Mexico Atlantis ecosystem model. • We simulated variability in catch and biomass under diet composition uncertainty. • We built a statistical emulator using simulated biomass and catch outputs. • The computationally-efficient emulator explored the complete parameter space. • Parameter uncertainty in diet composition affected the determination of oil effects. Abstract Oil spills can disrupt marine and coastal ecosystem services leading to reduced employment opportunities and income. Ecosystem models can be used to estimate the effects of oil pollution; however, uncertainty in model predictions may influence damage assessment. We performed an uncertainty analysis for the Atlantis ecosystem model of the Gulf of Mexico (Atlantis-GOM), under a scenario simulating the effects of the Deepwater Horizon oil spill. Atlantis-GOM simulates major biophysical processes, including the effects of oil hydrocarbons on fish growth and mortality. We used all available fish stomach content data to inform parameter distribution for the Atlantis-GOM availability matrix, which represents predator total consumption potential and diet preference. We sampled the fish diet composition distribution and analyzed the variability of functional group biomass and catch predicted by Atlantis-GOM simulations to changes in the availability matrix. Resulting biomass and catch were then used to fit statistical emulators of the ecosystem model and predict biomass and catch given the complete diet parameter space. We used simulated and emulated data to assess changes in recovery time to oil spill effects. Uncertainty in diet composition had large effects on model outputs and may, therefore, influence damage assessment of oil exposure on economically important species. [ABSTRACT FROM AUTHOR]

Oil hydrocarbons are widespread pollutants in sub-surface sediments with serious threats to terrestrial and aquatic environment. However, very limited data is available about remediation of historically contaminated sediments. This study reports the use of magnetite-catalyzed chemical oxidation (H 2 O 2 and Na 2 S 2 O 8 ) to degrade oil hydrocarbons in aged contaminated sediments. For this purpose, oil contaminated sediments were sampled from three different locations in France including two harbors and one petroleum industrial channel. These sediments were characterized by different hydrocarbon index (HI) values (3.7–9.0 g kg −1 ), total organic carbon contents (1.9%–8.4%) and textures (sand, slit loam and silt). Chemical oxidation was performed in batch system for one week at circumneutral pH by: H 2 O 2 alone, H 2 O 2 /Fe(II), H 2 O 2 /magnetite, Na 2 S 2 O 8 alone, Na 2 S 2 O 8 /Fe(II), and Na 2 S 2 O 8 /magnetite. Results obtained by GC-FID indicated substantial hydrocarbon degradation (40–70%) by H 2 O 2 /magnetite and Na 2 S 2 O 8 /magnetite. However, oxidants alone or with soluble Fe(II) caused small degradation (<5%). In the presence of H 2 O 2 /magnetite, degradation of extractable organic matter and that of HI were highly correlated. However, no such correlation was observed for Na 2 S 2 O 8 /magnetite which resulted in higher removal of HI indicating its selective oxidation behavior. Treatment efficiency was negatively influenced by organic carbon and carbonate contents. For being the first study to report chemical oxidation of oil hydrocarbons in real contaminated sediments, it may have practical implications to design a remediation strategy for target contaminants. [ABSTRACT FROM AUTHOR]

Pollution by oil has negative influence on all ecosystem of the sea. The main role in decomposing of hydrocarbons belongs to microorganisms. Influence emulsion and water repellencies of cellular walls of microorganisms on an oil destruction is noted.

Soil contamination with crude oil or petroleum residues is worldwide the major problem occurred consequently to exploitation, transport and processing. The presence of hydrocarbons leads to increased quantities of carbon and imbalances in C:N ratio with consequences on microbial life from soil. A wide variety of edaphic microorganisms including bacterial and fungal species are known as hydrocarbon bio-degraders, contributing to soil decontamination. Research has been carried out to characterize the microbial communities in soil contaminated with oil hydrocarbons by an accidental spill from broken pipes in Icoana, Olt county. The results revealed important decrease in both bacterial and fungal counts under the impact of contaminant hydrocarbons as compared to non-contaminated soil, accompanied by biodiversity loss (SR2 values 1.49 for bacteria and 2.32 for fungi comparatively with 7.02 and respectively 3.27 in non-contaminated soil). Low levels of global physiological activity of microorganisms registered in contaminated soil and 2.34 times higher levels in non-contaminated soil. Changes in species composition of microbial populations indicated moderate similarity between bacterial species lists (SI=67) and important dissimilarity between fungal species lists (SI=16). Hydrocarbon utilizers from microflora included pseudomonads, bacilli and cosmopolitan fungal species from genera Cladosporium, Fusarium, Sporothrix in contaminated soil and Trichoderma, Cladosporium, Aspergillus, Penicillium in non-contaminated soil. [ABSTRACT FROM AUTHOR]

Petroleum hydrocarbons are significant new persistent organic pollutants for marine oil spill risk areas. Oil trading ports, in turn, have become major bearers of the risk of offshore oil pollution. However, studies on the molecular mechanisms of microbial degradation of petroleum pollutants by natural seawater are limited. Here, an in situ microcosm study was conducted. Combined with metagenomics, differences in metabolic pathways and in the gene abundances of total petroleum hydrocarbons (TPH) are revealed under different conditions. About 88% degradation of TPH was shown after 3 weeks of treatment. The positive responders to TPH were concentrated in the genera Cycloclasticus, Marivita and Sulfitobacter of the orders Rhodobacterales and Thiotrichales. The genera Marivita, Roseobacter, Lentibacter and Glaciecola were key degradation species when mixing dispersants with oil, and all of the above are from the Proteobacteria phylum. The analysis showed that the biodegradability of aromatic compounds, polycyclic aromatic hydrocarbon and dioxin were enhanced after the oil spill, and genes with higher abundances of bphAa, bsdC , nahB, doxE and mhpD were found, but the photosynthesis-related mechanism was inhibited. The dispersant treatment effectively stimulated the microbial degradation of TPH and then accelerated the succession of microbial communities. Meanwhile, functions such as bacterial chemotaxis and carbon metabolism (cheA, fadeJ and fadE) were better developed, but the degradation of persistent organic pollutants such as polycyclic aromatic hydrocarbons was weakened. Our study provides insights into the metabolic pathways and specific functional genes for oil degradation by marine microorganisms and will help improve the application and practice of bioremediation. [Display omitted] • The presence of oil significantly increased the abundance of functional genes. • Dispersants accelerated the activation of microbial degradation of oil. • Dispersants enhanced the adaptability of microorganisms to oil-polluted conditions. • The degradation rate of total petroleum hydrocarbons was about 88%. The genes with higher abundances of bphAa, bsdC , nahB, doxE and mhpD were mainly enriched in the aromatic compound, polycyclic aromatic hydrocarbon, and dioxin degradation pathways in the microbial communities responsible for oil biodegradation in a typical port. [ABSTRACT FROM AUTHOR]

Polar environments are exposed to the risk of oil pollution. However, there is limited knowledge regarding how the variation of physicochemical factors influencing biodegradation may affect bacterial community structure. The effects of temperature (4, 10 and 20°C) and organic fertilization (Inipol EAP 22) on community structure and diversity of bacteria inhabiting Kerguelen sub-Antarctic waters were studied in crude- and diesel-amended microcosms. Dynamics of total (i.e., 16S rDNA-based) and metabolically active (i.e., 16S rRNA-based) bacterial community structure and diversity were monitored using capillary-electrophoresis single-strand conformation polymorphism. Results showed that total and active community structures were differently influenced by temperature and fertilization in the presence of hydrocarbons. Both fertilization and temperature induced changes in total community structure in the presence of crude oil and diesel. However, temperature showed a limited influence on active community structure, and fertilization induced changes in the presence of crude oil only. Simpson's index decreased for total bacterial communities at all temperatures in the presence of crude oil and diesel, whereas a lower reduction was observed for active bacterial populations. In the presence of fertilizer, the diversity of the whole community approached control values after seven incubation weeks; this was not observed for the active bacterial community. This study evidenced qualitative differences in total and active bacterial community structures of Kerguelen seawaters in the presence of hydrocarbons and different responses relative to variation in temperature and fertilization. These factors and hydrocarbons composition have to be taken into account to understand bacterial community dynamics after an oil spill.

Arbuscular mycorrhizal fungi (AMF) form mutualistic associations with the roots of 80–90% of vascular plant species and may constitute up to 50% of the total soil microbial biomass. AMF have been considered to be a tool to enhance phytoremediation, as their mycelium create a widespread underground network that acts as a bridge between plant roots, soil and rhizosphere microorganisms. Abundant extramatrical hyphae extend the rhizosphere thus creating the hyphosphere, which significantly increases the area of a plant's access to nutrients and contaminants. The paper presents and evaluates the role and significance of AMF in phytoremediation of hydrocarbon contaminated sites. We focused on (1) an impact of hydrocarbons on arbuscular mycorrhizal symbiosis, (2) a potential of AMF to enhance phytoremediation, (3) determinants that influence effectiveness of hydrocarbon removal from contaminated soils. This knowledge may be useful for selection of proper plant and fungal symbionts and crucial to optimize environmental conditions for effective AMF-mediated phytoremediation. It has been concluded that three-component phytoremediation systems based on synergistic interactions between plant roots, AMF and hydrocarbon-degrading microorganisms demonstrated high effectiveness in dissipation of organic pollutants in soil. [ABSTRACT FROM AUTHOR]

The bioremediation of the soils which were contamined with oil hydrocarbons constitutes an active preoccupation on the national and international level as well. In this paper is presented the situation of soils from Romania regarding their pollution with oil hydrocarbons and are enumerated the most important bioremediation technologies and the most important factors which can influence the treatment of oil hydrocarbons polluted soils. [ABSTRACT FROM AUTHOR]

This review presents a comprehensive summary of the latest research in the field of bioremediation with filamentous fungi. The main focus is on the issue of recent progress in remediation of pharmaceutical compounds, heavy metal treatment and oil hydrocarbons mycoremediation that are usually insufficiently represented in other reviews. It encompasses a variety of cellular mechanisms involved in bioremediation used by filamentous fungi, including bio-adsorption, bio-surfactant production, bio-mineralization, bio-precipitation, as well as extracellular and intracellular enzymatic processes . Processes for wastewater treatment accomplished through physical, biological, and chemical processes are briefly described. The species diversity of filamentous fungi used in pollutant removal, including widely studied species of Aspergillus , Penicillium , Fusarium , Verticillium , Phanerochaete and other species of Basidiomycota and Zygomycota are summarized. The removal efficiency of filamentous fungi and time of elimination of a wide variety of pollutant compounds and their easy handling make them excellent tools for the bioremediation of emerging contaminants. Various types of beneficial byproducts made by filamentous fungi, such as raw material for feed and food production, chitosan, ethanol, lignocellulolytic enzymes, organic acids, as well as nanoparticles, are discussed. Finally, challenges faced, future prospects, and how innovative technologies can be used to further exploit and enhance the abilities of fungi in wastewater remediation, are mentioned., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ghosh, Rusyn, Dmytruk, Dmytruk, Onyeaka, Gryzenhout and Gafforov.)

A biopreparation inducing oil destruction and increasing the biological activity of soils was developed on the basis of activated sludge. Its oxidative activity towards hydrocarbons was studied. The application of this biopreparation to oil-contaminated soil increased the population density of microorganisms, including destroyers of hydrocarbons, and accelerated oil decomposition. The degree of destruction of oil and oil products in the case of a single treatment of the soil with this biopreparation comprised 30 to 50% within 60 days. The presence of cellulose-decomposing microorganisms in this biopreparation also favored an accelerated decomposition of plant substances, including plant litter and sawdust applied to the urban soils as an adsorbent. [ABSTRACT FROM AUTHOR]

There is growing concern that modifications to the global environment such as ocean acidification and increased ultraviolet radiation may interact with anthropogenic pollutants to adversely affect the future marine environment. Despite this, little is known about the nature of the potential risks posed by such interactions. Here, we performed a multifactorial microcosm experiment to assess the impact of ocean acidification, ultraviolet B (UV-B) radiation and oil hydrocarbon contamination on sediment chemistry, the microbial community (composition and function) and biochemical marker response of selected indicator species. We found that increased ocean acidification and oil contamination in the absence of UV-B will significantly alter bacterial composition by, among other things, greatly reducing the relative abundance of Desulfobacterales, known to be important oil hydrocarbon degraders. Along with changes in bacterial composition, we identified concomitant shifts in the composition of oil hydrocarbons in the sediment and an increase in oxidative stress effects on our indicator species. Interestingly, our study identifies UV-B as a critical component in the interaction between these factors, as its presence alleviates harmful effects caused by the combination of reduced pH and oil pollution. The model system used here shows that the interactive effect of reduced pH and oil contamination can adversely affect the structure and functioning of sediment benthic communities, with the potential to exacerbate the toxicity of oil hydrocarbons in marine ecosystems. [ABSTRACT FROM AUTHOR]

This paper describes the problem of oil pollutant removal and the use of Acinetobacter genus microorganisms in oil biodegradation. As part of the experiments, Acinetobacter genus microorganism strain with he best ability to degrade crude oil and fuel oil in saline waters was selected from the microorganism collection of JSC "Biocentras". The impact of environmental conditions (salinity, temperature, pH, substrate concentation) on this strain's viability and the efficacy of its oil degradation processes were evaluated. The most efficient degradation of oil products by Acinetobacter genus bacteria was at temperature of 30 °C, in a pH range of 7-8, in model ocean water of 35 ‰ salinity. [ABSTRACT FROM AUTHOR]

The article is dedicated to analyzing the content and distribution of oil hydrocarbons, benz(a)pyrene, and heavy metals in the soils of the southern part of Sakhalin Island. The investigations were conducted in 2003-2010. A dynamical increase in the content of ecotoxicants in soils has been shown. The similar character of the accumulation of oil hydrocarbons, benz(a)pyrene, and heavy metals in the soils has been determined and indicates the possibility of the aerial transmission of pollutants from existing nearby sources. [ABSTRACT FROM AUTHOR]

The results of monitoring studies of organic matter content of bottom sediment, water, and surface microlayer carried out during expeditions of 2000-2004 in northwestern Caspian Sea are presented. [ABSTRACT FROM AUTHOR]

This study considers treatment of real city rain sewage under the action of an oxygen dielectric barrier discharge (DBD) at atmospheric pressure in the presence or absence of TiO catalyst in the plasma zone. The DBD discharge has been shown to have high decomposition efficiency (up to 98%) for oil hydrocarbons, phenols and synthetic surfactants. The discharge action resulted in the decrease of heavy metal (Pb, Cd, Fe, Mn) content as well. In a plasma-catalytic hybrid process, the efficiency of organic substances decomposition was higher than efficiency for the DBD treatment without catalyst. [ABSTRACT FROM AUTHOR]

Abstract: We generalized experimental data on the structural group composition and macrostructural characteristics of high-molecular compounds (HMCs)—hydrocarbons, resins, and asphaltenes—from more than 180 crude oil samples extracted from different oil fields of Eurasia. Most of oil resin molecules contain 1–3 structural blocks, each consisting of 0–3 aromatic and 0–5 naphthenic rings in different combinations, with the total number of rings in each block not exceeding 5–6. The average molecular weights of resins are no more than 100–1500 a.m.u. Asphaltenes differ from resins from the same source in the larger number of structural blocks (mainly tri- or tetracyclic aromatic) in molecule (up to five), lower degrees of substitution of aromatic cores, and smaller portions of carbon atoms in saturated fragments. The average molecular weights of asphaltenes measured by naphthalene cryoscopy do not exceed 2500 a.m.u. Owing to intermolecular interactions, HMCs form various associates and polymolecular particles, including quasi-crystalline “batches” and multibatch aggregates. Spontaneous disintegration and formation of such particles make the oils dynamically equilibrium polydisperse systems. We have developed the main regularities of compositional and structural changes of HMCs depending on the depth of occurrence, age, and lithologic composition of oil-bearing deposits. Being chemically labile heteroatomic substances, petroleum HMCs are more rapidly subjected to compositional and structural transformations than hydrocarbons, i.e., are more responsive to changes in strata conditions. [Copyright &y& Elsevier]

The dynamics of total and active microbial communities were studied in seawater microcosms amended with crude or diesel oil at different temperatures (25, 10 and 4 °C) in the presence/absence of organic fertilization (Inipol EAP 22). Total and hydrocarbon-degrading microbes were enumerated by fluorescence microscopy and Most Probable Number (MPN) method, respectively. Total (16S rDNA-based) vs. active (16S rRNA) bacterial community structure was monitored by Capillary-Electrophoresis Single Strand Conformation Polymorphism (CE-SSCP) fingerprinting. Hydrocarbons were analyzed after 12 weeks of incubation by gas chromatography–mass spectrometry. Total and hydrocarbon-degrading microbial counts were highly influenced by fertilization while no important differences were observed between temperatures. Higher biodegradation levels were observed in fertilized microcosms. Temperature and fertilization induced changes in structure of total bacterial communities. However, fertilization showed a more important effect on active bacterial structure. The calculation of Simpson's diversity index showed similar trends among temperatures whereas fertilization reduced diversity index of both total and active bacterial communities. [Copyright &y& Elsevier]

Ecotoxicological tests were carried out to determine the effects of crude oil, Diesel 2 and kerosene on the population growth of the diatom Chaetoceros gracilis. The mean effective concentration (CE50%) at an exposure time of 96 h was determined. The solution with Diesel 2 was more toxic (90 mg⋅L-1), followed by the solution with kerosene (98 mg⋅L -1) and the solution with crude oil (867.5 mg⋅L-1 ). In addition, the effects of the three organic compounds on the intrinsic population growth rate and division rate of Ch. gracilis were assessed. [ABSTRACT FROM AUTHOR]

Studies were conducted using a 10-chamber Micro-Oxymax (Columbus, OH, USA) respirometer to determine the effect of bioaugmentation and biostimulation (by diverse ways of O2 supply) on enhancing biodegradation of oil hydrocarbons to reduce risk at a former military airport in Kluczewo, Poland. Indigenous or exogenous bacteria bioaugmentation was used to degrade hydrocarbons. Aerated water and/or aqueous solutions of H2O2 or KMnO4 were used to supply O2. The intrinsic and enhanced biodegradation was evaluated by the O2 uptake and CO2 production rates obtained using a linear regression of the cumulative O2 uptake and CO2 production curves. Generally, in all cases biodegradation rates enhanced by bioaugmentation were two to four times higher than the rates of intrinsic biodegradation. Moreover, application of indigenous bacteria was more efficient in comparison to the exogenous consortia. The highest CO2 production rates were achieved when aqueous solution of KMnO4 was applied, as the increase of CO2 production rates were about 71% to 97% higher compared to a control. The aqueous solution of H2O2 did not cause any significant improvement of the biodegradation rates. Compared to a control, the addition of aerated water resulted in a decrease of CO2 production rates. Most probably the excessive soil moisture could reduce the air-filled porosity and, consequently, the oxygen contents in soil. [ABSTRACT FROM AUTHOR]

As one of the largest river systems attached to the Arctic Basin, the Ob–Yenisey watershed has the potential to be a major supply route of persistent organic pollutants into marine ecosystems of the Arctic Ocean. Snowfall and ice formation taking place in the Ob–Yenisey river basin and shelf are key components of the system of processes responsible for the transfer of pollutants from this high latitude river to the adjacent Kara and Barents Seas. Here we examine a large data set on persistent organic pollutants in snow and ice determined for areas within the Ob (interior and coastal), Yenisey and adjacent shelf. Data on the levels of total oil hydrocarbons, as well as individual components for groups (PAHs, HCHs, CBs, DDTs, PCBs) were examined in this investigation for two time periods: winter (1992)–spring (1993) and winter (1993)–spring (1994). Spatial averaging of each data set for individual years was performed in order to identify large-scale geographical trends in contaminant distributions within the four regions. The analysis indicates that mean pollutant concentrations in snow are consistent throughout the watershed. Comparing data from 1992/1993 and 1993/1994, in all cases, concentrations do not vary appreciatively among the different regions. A similar finding was observed for concentrations of pollutants in ice. Persistent organic pollutants for the Ob–Yenisey watershed are in most cases not dissimilar to measurements carried out in the far north of Canada. The exception is ∑DDT. Concentrations of this pollutant are an order of magnitude higher in the Ob–Yenisey watershed as compared to the Canadian Arctic (0.09 ng/l). [Copyright &y& Elsevier]