Biodegradation Of Oil Hydrocarbons Research Articles

Compositional change of bacterial communities in oil-polluted seawater amid varying degrees of nanoplankton bacterivory

Petroleum hydrocarbons are being released into the marine environment continuously. They will undergo weathering and may eventually be biodegraded by bacteria and other microbes. While nanoplankton (2–20 μm) are the major consumers of marine bacteria, their effect on the process of biodegradation of oil hydrocarbons is still debated. A 14-day microcosm experiment was conducted to investigate the effects of crude oil hydrocarbons on nanoplankton bacterivory and bacterial community in coastal waters. The coefficients of population growth (0.56–1.80 d−1 for all treatments considered) and grazing mortality (0.38–1.65 d−1 for all treatment considered) of bacteria estimated with the dilution method did not differ among the treatments of control (Ctrl), low dose chemically dispersed oil (LDOil, 2 μL L−1 of crude oil), and high dose chemically dispersed oil (HDOil, 8 μL L−1 of crude oil). Bacterial abundance ranged between 0.21–0.86 × 106 cells mL−1 on average for all treatments. The lack of drastic increases in the cell density of bacterial cells in the oil-loaded treatments was observed throughout the experiment period. Sequencing analysis of the 16S rRNA gene revealed the progressive changes in the community compositions of bacteria in all treatments. The relatively high abundance of oil-degrading bacteria, including Cycloclasticus and Alcanivorax on Days 3–14 of the experiment reflected the presence of biodegradation of oil in the LDOil and HDOil treatments. Throughout the 14 days, the community composition of bacteria in the LDOil and HDOil treatments became more similar and they both differed from that in the Ctrl treatment. This study concluded that, in oil-polluted seawater, the changes in the bacterial community composition were mainly resulting from the addition of chemically dispersed crude oil.

REMEDIATION OF OIL-CONTAMINATED SOILS WITH COMPOSITIONS BASED ON HUMIC ACIDS

In addition to conventional methods, nowadays new approaches and technologies based on combined application of sorbents and microorganisms are intensively developed for efficient control of oil contaminations. As a biotechnological solution for remediation of various oil-contaminated soils, biocompositions based on an organic matrix – humic acids of peat, and a biological component – a single strain/or an association of oil degrading microorganisms of the genera Rhodococcus and Pseudomonas, have been studied. The efficiency assessment of oil contamination biodegradation using biocompositions was carried out on different types of model oil-contaminated soils with different levels of contamination: grey forest soil, Black Sea pebbles (fraction 20-50mm), constructional broken stone (fraction 10-20mm). Natural soil contaminated with oil products and samples of railroad broken stone (fractions 5-30mm and 35-50mm) were also used. It has been shown that the biocompositions based on three strains of microorganisms – ‘HA R. X5 R. S67 Ps. NF142' – possessed the highest capability of degrading oil hydrocarbons in all systems under study. Biodegradation of oil hydrocarbons upon addition of this biocompositions varied between 62 and 82% depending on the type of oil-contaminated soil, the level of contamination being very high. Monobacterial biocomposition ‘HA Ps.NF142’ has proven to be promising for remediation of oil-contaminated soil ecosystems with a high and very high level of contamination. The increase of the level of biodegradation of oil contamination of soils appears to be due to the combined action of humic acids comprising both the stimulating effect of humic acids on microorganisms – the components of biocompositions and indigenous microflora of model systems, and the detoxifying effect of humic acids in respect of oil hydrocarbons. For citation: Grechishcheva N.Yu., Dmitrieva E.D., Starodubtseva K.A. Remediation of oil-contaminated soils with compositions based on humic acids. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 7. P. 136-143. DOI: 10.6060/ivkkt.20246707.6927.

Biodegradation of Selected Hydrocarbons by Fusarium Species Isolated from Contaminated Soil Samples in Riyadh, Saudi Arabia

Microbial biodegradation of oil-hydrocarbons is one of the sustainable and cost-effective methods to remove petroleum spills from contaminated environments. The current study aimed to investigate the biodegradation abilities of three Fusarium isolates from oil reservoirs in Saudi Arabia. The novelty of the current work is that the biodegradation ability of these isolates was never tested against some natural hydrocarbons of variable compositions, such as Crude oil, and those of known components such as kerosene and diesel oils. The isolates were treated with five selected hydrocarbons. The hydrocarbon tolerance test in solid and liquid media was performed. The scanning electron microscope (SEM) investigated the morphological changes of treated fungi. 2, 6-Dichlorophenol Indophenol (DCPIP), drop collapse, emulsification activity, and oil Spreading assays investigated the biodegradation ability. The amount of produced biosurfactants was measured, and their safety profile was estimated by the germination assay of tomato seeds. The tolerance test showed enhanced fungal growth of all isolates, whereas the highest dose inhibition response (DIR) was 77% for Fusarium proliferatum treated with the used oil (p < 0.05). SEM showed morphological changes in all isolates. DCPIP results showed that used oil had the highest biodegradation by Fusarium verticillioides and Fusarium oxysporum. Mixed oil induced the highest effect in oil spreading, drop collapse, and emulsification assay caused by F. proliferatum. The highest recovery of biosurfactants was obtained by the solvent extraction method for F. verticillioides (4.6 g/L), F. proliferatum (4.22 g/L), and F. oxysporum (3.73 g/L). The biosurfactants produced by the three isolates stimulated tomato seeds' germination more than in control experiments. The current study suggested the possible oil-biodegradation activities induced by three Fusarium isolates from Riyadh, Saudi Arabia. The produced biosurfactants are not toxic against tomato seed germination, emphasizing their environmental sustainability. Further studies are required to investigate the mechanism of biodegradation activities and the chemical composition of the biosurfactants produced by these species.

DETOXIFYING ABILITY OF PEAT HUMIC ACIDS TO PETROLEUM PRODUCTS IN THE SOIL ECOSYSTEM

The stimulating effect of humic acids on the growth of the biomass of the test object was established. А series of positive effects on the biomass of seedlings was proposed. The correlation dependence of the effect of toxicants on the cockweed on its composition was revealed. It was shown that the light ends of oil has a minimal toxic effect on cockweed due to increased volatility, in contrast to petroleum. The detoxifying ability of peat humic acids was established separately and together with oil-degrading microorganisms of the genus Rhodococcus on the inert substrate by the method of biotesting. Humic acids had a stimulating effect on the test object regardless of their genesis. The maximum stimulating effect on the test object was exhibited by humic acids isolated from fen peats. The biomass of cockweed seedlings on contaminated soil in the presence of humic acids and microorganisms of the genus Rhodococcus in all variants of experiments with model toxicants was higher compared to the variant without treatment with humic acids. The detoxification coefficients of humic acids were calculated separately and together with oil-degrading microorganisms of the genus Rhodococcus in the relation to hexadecane: the humic acids of sphagnum high-moor peat and sphagnum transitional peat showed the maximum detoxifying effect: 70−75%. Combined use of humic acids and microorganisms Rh. erythropolis S67, Rh. erythropolis X5 increased the detoxifying effect of humic acids by 4−22%. The values of the detoxification coefficients vary in the range of 59−85%, depending on the genesis of humic acids and the selected strain of microorganisms. The values of the detoxification coefficients of humic acids together with moil-degrading microorganisms of the genus Rhodococcus exceed the indicators of control and experimental options using only humic acids due to the ability of Rhodococcus to produce biologically active surfactants capable of more emulsification and biodegradation of oil hydrocarbons in the environment.

Approaches to Determining Maximum Permissible Concentrations of Oil and Oil Products for Different Soil Types on the Basis of the Assimilation Potential (by the Example of Azerbaijan Soils)

The assimilation potential to oil and oil hydrocarbons is assessed for the first time for different soil types of Azerbaijan. The soil assimilation potential is understood as the buffering capacity of soils to sustain a certain anthropogenic impact without changing their principal properties and ecological functions for a long period. Estimation of assimilation potential of a territory is necessary for assessing the actual self-purification capacity of environmental components as a national ecological resource under the conditions of constantly growing anthropogenic impact on the environment. For assessing the assimilation potential of soils in respect to oil hydrocarbons, the value of bacterial biodegradation of oil hydrocarbons has been evaluated according to the amount of hydrocarbon-oxidizing bacteria and the number of hydrocarbons that are oxidized by one bacterial cell. It is found that the assimilation potential of different soil types in Azerbaijan (provided they are contaminated with oil hydrocarbons) varies from 1 t/ha per year for solonchaks to 12.5–13.1 t/ha per year for chestnut (Kastanozems) and mountain chernozemic (Chernozems) soils. The index of actual assimilation potential for various soil types may be accepted as the upper safe level of the permissible hydrocarbon concentration.

Oil Hydrocarbon Degradation by Caspian Sea Microbial Communities.

The Caspian Sea, which is the largest landlocked body of water on the planet, receives substantial annual hydrocarbon input from anthropogenic sources (e.g., industry, agriculture, oil exploration, and extraction) and natural sources (e.g., mud volcanoes and oil seeps). The Caspian Sea also receives substantial amounts of runoff from agricultural and municipal sources, containing nutrients that have caused eutrophication and subsequent hypoxia in the deep, cold waters. The effect of decreasing oxygen saturation and cold temperatures on oil hydrocarbon biodegradation by a microbial community is not well characterized. The purpose of this study was to investigate the effect of oxic and anoxic conditions on oil hydrocarbon biodegradation at cold temperatures by microbial communities derived from the Caspian Sea. Water samples were collected from the Caspian Sea for study in experimental microcosms. Major taxonomic orders observed in the ambient water samples included Flavobacteriales, Actinomycetales, and Oceanospirillales. Microcosms were inoculated with microbial communities from the deepest waters and amended with oil hydrocarbons for 17 days. Hydrocarbon degradation and shifts in microbial community structure were measured. Surprisingly, oil hydrocarbon biodegradation under anoxic conditions exceeded that under oxic conditions; this was particularly evident in the degradation of aromatic hydrocarbons. Important microbial taxa associated with the anoxic microcosms included known oil degraders such as Oceanospirillaceae. This study provides knowledge about the ambient community structure of the Caspian Sea, which serves as an important reference point for future studies. Furthermore, this may be the first report in which anaerobic biodegradation of oil hydrocarbons exceeds aerobic biodegradation.

Metagenomic evaluation of a Utah tar sand microbiota suggests the predominant hydrocarbonoclastic role of Actinobacteria

Background: Occurrences of tar sands have been reported in 22 states in the United States; however, the largest deposit is located in southwestern Utah. It has been suggested that tar sands were created by the microbial degradation of immobile subsurface oil over several million years; however, little is known about the indigenous microbial communities in the bituminous tar sands. Methods: This study identified Utah tar sand microbiota using next-generation sequencing technology and characterized the functional diversity using community-level physiological profile (CLPP). Results: Microbiota identified in these tar sands are mainly affiliated with the Gram-positive Actinobacteria and representatives of genera that have also been previously shown to degrade aromatic hydrocarbons, including Arthrobacter, Dietzia, Janibacter, Nocardioides, Microbacterium, Agrococcus and Salinibacterium, suggesting that these microbes likely play roles in the biodegradation of oil-hydrocarbons. CLPP analysis revealed less than 24 h was needed for the first color development in the microplate wells containing the polymers, whereas the duration of the lag phase of the carboxylic acids was prolonged. Conclusions: The quick utilization of the polymers suggests that the indigenous microbial community, especially the actinomycetes in the tar sand habitat, are poised and primed to degrade these recalcitrant compounds.

Features of bitumoids composition of bottom sediments of the coastal zone of the East Siberian Sea

An anthropogenic influence, in particular, oil contamination on the Arctic ecosystems is studied. For this composition of the chloroform bitumoids extracted from the samples of bottom sediments is explored. The samples were taken near seaport Kolyma River and a coastal zone of the East Siberian Sea. In bottom sediments of the seaport the yeild of bitumoid reached 25500 mkg g-1. As appeared, their samples were oil contaminated. Hydrocarbons prevailed significantly over the sum of resinous components in their composition as aliphatic compounds dominated over oxygen groups in chemical structure. N-alkanes maked up 28% of the sum of the identified hydrocarbons with a distribution maximum in the area nC15,16. CPI is typical for oil and oil products. The values of ratio of isoprenoids to n-alkanes and the distribution of isoprenoids point to processes of biodegradation of oil hydrocarbons. In the sea samples the yield of bitumoid much less 193-1577 mkg g-1 and oil contamination traces aren’t found. The future of chemical structure and distribution of individual saturated hydrocarbons reveal a strong relationship with terrigenous organic matter of recent deposits. The prevalence of odd hydrocarbons nC23-nC35 and high concentrations nC27, nC29, nC31 is characteristic for lipids of highest land plants.

Efficiency of Rye Biomass on Oil Hydrocarbon Biodegradation

The majority of the plants secrete their enzymes in the soil, where they can decompose various organic compounds. Extra cellular plant enzymes can be effective against a number of contaminants. To estimate the plants, their enzymes and micro-organism effect on hexadecane content in the soil, the sterile soil samples was amended with 0.5 % hexadecane and sowed with accordingly prepared rye seeds. Till increasing the quantity of micro-organisms and the formation of rye seedlings, hexadecane content remained practically unchanging in all samples. After 21 days hexadecane content in the soil with rye seedlings was about 5 % of the contributed content. The intrinsic soil processes through 21 days to shrank the hexadecane content in the soil without rye seedlings up to 17 %. Oxidases, catalases and peroxidases were detected in rye biomass during all test period. As shown by the results, polyphenoloxydases were detected only in root biomass, the early germs of germination and roots formation stages.

Evaluating the Detection of Hydrocarbon-Degrading Bacteria in 16S rRNA Gene Sequencing Surveys.

Hydrocarbonoclastic bacteria (HCB) play a key role in the biodegradation of oil hydrocarbons in marine and other environments. A small number of taxa have been identified as obligate HCB, notably the Gammaproteobacterial genera Alcanivorax, Cycloclasticus, Marinobacter, Neptumonas, Oleiphilus, Oleispira, and Thalassolituus, as well as the Alphaproteobacterial genus Thalassospira. Detection of HCB in amplicon-based sequencing surveys relies on high coverage by PCR primers and accurate taxonomic classification. In this study, we performed a phylogenetic analysis to identify 16S rRNA gene sequence regions that represent the breadth of sequence diversity within these taxa. Using validated sequences, we evaluated 449 universal 16S rRNA gene-targeted bacterial PCR primer pairs for their coverage of these taxa. The results of this analysis provide a practical framework for selection of suitable primer sets for optimal detection of HCB in sequencing surveys.

Biodegradation of oil hydrocarbons with psychrophilic strain

Biodegradation of oil hydrocarbons with psychrophilic strain

Working out of receptions of bioremediation masout sewage

Hydrochemical and microbiological analysis of residual masout sewage was carried out. It was revealed that the native microflora takes active part in biodegradation of oil hydrocarbons. Injection of cyano-bacterial communities and water plants activates processes of self-cleaning of sewage from oil products. About this testify a decrease of total oil hydrocarbons – on 98%; optical density – on 71%.

Bioremediation of oil-polluted soils: Using the [13C]/[12C] ratio to characterize microbial products of oil hydrocarbon biodegradation

Bioremediation of oil-polluted soils: Using the [13C]/[12C] ratio to characterize microbial products of oil hydrocarbon biodegradation

E Ffectiveness of Intrinsic Biodegradation Enhancement in Oil Hydrocarbons Contaminated Soil

Abstract Studies were conducted using a 10-chamber Micro-Oxymax (Columbus, OH, USA) respirometer to determine the effect of bioaugmentation, biostimulation and combination of them on enhancing intrinsic biodegradation of oil hydrocarbons in soil. Contaminated soil was collected from a former military airport in Kluczewo, Poland. Bioaugmentation was realized by addition of indigenous or exogenous bacteria to soil. Biostimulation was done by aerated water supply and surfactant addition. Bioaugmentation + addition of a surfactant was applied as the combined treatment. The intrinsic and enhanced hydrocarbons biodegradation rates were estimated from the slopes of linear regressions of cumulative curves of O2 uptake. Pertinent biodegradation rates were recalculated on the basis of the stoichiometric reaction (mass balance equation) and conversion equation. The results showed that combined treatment (indigenous bacteria bioaugmentation + addition of a surfactant) was the most effective method of biodegradation enhancement as the 20-fold increase of biodegradation rate was observed.

Bioremediation of oil-polluted soils: using the [13C]/[12C] ratio to characterize microbial products of oil hydrocarbon biodegradation

We compared data on the extent of bioremediation in soils polluted with oil. The data were obtained using conventional methods of hydrocarbon determination: extraction gas chromatography-mass spectrometry, extraction IR spectroscopy, and extraction gravimetry. Due to differences in the relative abundances of the stable carbon isotopes (13C/12C) in oil and in soil organic matter, these ratios could be used as natural isotopic labels of either substance. Extraction gravimetry in combination with characteristics of the carbon isotope composition of organic products in the soil before and after bioremediation was shown to be the most informative approach to an evaluation of soil bioremediation. At present, it is the only method enabling quantification of the total petroleum hydrocarbons in oil-polluted soil, as well as of the amounts of hydrocarbons remaining after bioremediation and those microbially transformed into organic products and biomass.

Metabolite Analysis as Direct Proof of Biodegradation: Experience from Monitored Natural Attenuation (MNA) Projects

Signature metabolites provide direct geochemical indication that in-situ biodegradation of released organic compounds (e.g., oil and its refined products) is occurring. Experience shows that monitored natural attenuation site conditions are often more complex than in theory and often require a more profound comprehension of the governing natural attenuation processes. Frequently, there is lack of direct proof that contaminant degradation (mainly through biodegradation) is occurring. Advanced tools are emerging that aim to provide answers about whether contaminants of concern are actually (bio)degraded and to the extent. Signature metabolite analysis provides direct proof of mineral oil hydrocarbon biodegradation and is among these advanced tools. Yet, during the previous 15 years, metabolite analysis has only been used sporadically in research projects. The target metabolites consist of aromatic acids such as benzoates and benzylsuccinates and uniquely indicate in-situ biodegradation of individual contaminants of concern. Three case studies have been summarized to share practical experience with signature metabolite analysis for contaminants that include benzene, toluene, ethyl benzene, and xylenes; trimethylbenzenes; and polycyclic aromatic hydrocarbons. The summarized case study involving jet fuel-contamination was the first reported field study in which aromatic acid homologs were formed by microbial metabolism of C4 through C7 benzene. Signature metabolite analysis can be used to improve understanding of natural attenuation processes to close data gaps with respect to the general degradation mechanisms. Direct evidence for biodegradation (e.g., metabolite identity and concentration; microbial identity and quantity; daughter product degradation ratios, stable carbon isotope ratios) facilitates remediation planning and management; provides information useful to scientists and engineers that must determine the mechanisms that produced observed environmental conditions; and provides information for stakeholders involved in environmental cleanup litigation and cost appropriation.

Effectiveness of Bioremediation Processes of Hydrocarbon Pollutants in Weathered Drill Wastes

The aim of this article is to present the problem of purification of 50-year-old weathered wastes (soil) from waste pits—the result of oil drilling. The soil was deeply contaminated with petroleum hydrocarbons—total petroleum hydrocarbon (TPH) level: 85,654–101,842 mg kg dry mass. This work presents results of waste pit material purification with the use of stage technology: initial reclamation, basic bioremediation, and bioaugmentation (inoculation with indigenous microorganisms). The whole process was controlled with the use of gas chromatography/flame ionization detector. This analytical method enables observation of alternation in n-alkanes content during the consecutive stages of purification. According to this method, estimation of oil hydrocarbon biodegradation degree with the use of n-C17/Pr and n-C18/F indicators can be done. The use of biomarker C30-17α(H)21β(H)-hopane to normalize the TPH concentration in laboratory research enabled the creation of the first-order mathematical model of biodegradation. It is possible to recognize the dynamics of the following purification stages due to the calculated first-order biodegradation constants. Decrease in the TPH content (63.8–65.1%) was a result of laboratory tests led in 130 days of basic bioremediation. The next stage of soil purification (130 days) included inoculation with biopreparation based on indigenous microorganisms—TPH decrease in 80.7–81.7%. Laboratory tests results enabled elaboration of purification methods applied in tested waste pits in industrial conditions (in situ). The technology of the G-44 and G-12 waste pits purification from huge petroleum hydrocarbons content, consisting of stage purification process, enables the TPH decrease to the satisfactory level in 3 years.

Effect of UV radiation transmitted through light-correcting films on the enzymatic activity of oil-polluted soil

The effect of photoluminescent (light-correcting) polymeric films on the enzymatic activity of microorganisms in oil-polluted soil was investigated under laboratory conditions. The efficiency of the use of films as a covering material containing organic and inorganic photoluminophores was studied under the UV-irradi-ation of the soil polluted with oil products in a concentration of up to 50 g/kg. The application of light-correcting films increases the activity of enzymes in oil-polluted soil: catalase by a factor of 2–4, dehydrogenase 2.5, urease 4.5, polyphenoloxidase and peroxidase by a factor of 2–3. In this situation, as chromatographic investigations showed, biodegradation of oil hydrocarbons polluting the soil proceeds 5–6 times faster in comparison with the reference versions for which a usual polymeric high-pressure polyethylene film was used.

Potential of Bioaugmentation and Biostimulation for Enhancing Intrinsic Biodegradation in Oil Hydrocarbon-Contaminated Soil

ABSTRACT 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.

Bioaugmentation as a method of biodegradation enhancement in oil hydrocarbons contaminated soil

Respirometry studies using the 10-chamber Micro-Oxymax respirometer (Columbus, Ohio) were conducted to determine the effect of adding bacterial consortium for enhancing biodegradation in soils contaminated with oil hydrocarbons from the former military airport. Bioaugmentation was carried out using both indigenous and extraneous bacteria able to degrade hydrocarbons. The potentials of intrinsic and enhanced biodegradation were evaluated by the mean O2 uptake and CO2 production rates. The results demonstrated that the highest biodegradation rates were achieved using bacterial consortium containing 4.8×1015 Colony Forming Units (CFU) cm−3. Generally, in all cases, enhanced biodegradation rates were four times higher than intrinsic biodegradation rates. Moreover, application of indigenous bacterial consortia was more efficient in comparison to the employment of extraneous bacterial consortia. This study showed that bioaugmentation could be an effective method for enhancing intrinsic biodegradation of oil hydrocarbons in soil.