Biodegradation Of Oil In Soil Research Articles

Inorganic and Organic Fe Sources Increased Crude Oil Biodegradation in Soil Under Cultivation of the Canola Plant Inoculated with Piriformospora indica

Inorganic and Organic Fe Sources Increased Crude Oil Biodegradation in Soil Under Cultivation of the Canola Plant Inoculated with <i>Piriformospora indica</i>

Prediction of changes in the number of native oil-oxidizing microorganisms and degradation of reduced fuel oil in soil using the methods of mathematical modeling

Nowadays, the problem of the environment protection from pollution resulting from the spill of crude oil and products of oil processing, in particular reduced fuel oil, is very acute in the fuel and energy industry. An experimental study of the process of reduced fuel oil biodegradation in soil at various concentrations of pollution (5 and 10 g/kg), by the association of native oil-oxidizing microorganisms, was carried out in this work. Based on the obtained experimental data, a mathematical model is proposed that can be used to describe the process of biodegradation of reduced fuel oil and the concentration dynamics of oil-oxidizing microorganisms in contaminated soil. The results of numerical modeling demonstrated a fairly good qualitative and quantitative agreement with the results of experimental studies. The use of the developed mathematical model at the early stages of cleaning will make it possible to evaluate the results of various scenarios for cleaning soils contaminated with fuel oil, oil or oil products using native oil-oxidizing microorganisms and choose the most effective method. Keywords: reduced fuel oil; oil-contaminated soil; native oil-oxidizing microorganisms; mathematical modeling.

Indole-3-Acetic Acid and Humic Acid Increase the Bio-Degradation of Diesel Oil in Soil Polluted with Pb and Cd

Introduction: Soil remediation is one of the most important fields in environmental studies. This study was conducted to investigate the effect of indole-3-acetic acid (IAA) and humic acid (HA) on increasing the bio-degradation of diesel oil in soil polluted with (lead) Pb and cadmium (Cd). Materials and Methods: Treatments included foliar application of IAA (0 (control) and 30 ppm) and soil application of HA (0 (control) and 200 mg/kg soil) in the soil contaminated with Cd (0 (control), 10 and 15 mg/kg soil), Pb (0 (control) and 1600 mg/kg soil), and diesel oil (0 (control), and 8% (W/W)). The sunflower was planted in all soil samples. The plants were harvested after 70 days and Pb and Cd concentrations of plants were measured using Atomic Absorption Spectroscopy. Results: Foliar application of IAA at the rate of 30 mg/l significantly increased the Cd and Pb phytoremediation by 14.8% and 13.4%, respectively. For HA application, it was increased by 11.3% and 10.2%, respectively. A significant increase was found in degradation percentage of diesel oil in soil by 12.6%, when the soil was treated with 200 mg HA/kg soil. Conclusion: It can be concluded that application of organic amendments such as IAA or HA can be a suitable way for increasing plant growth and increasing plant phytoremediation efficiency, especially in the soil contaminated with diesel oil. However, the phytoremediation efficiency is dependent on the plant physiology and the type of soil pollution that should be considered.

Mutual effects of crude oil and plants in contaminated soil: a field study.

The effect of oil contamination on growth of mono- and dicotyledonous plants (clover and ryegrass), on the one hand, and the effect of plants on oil biodegradation in soil, on the other hand, were studied in a long-term field experiment. It was found that plants respond differently to oil contamination of soddy-podzolic soil. Clover was more resistant to oil than ryegrass. Biosynthesis of photosynthetic pigments (chlorophylls and carotenoids) was not disturbed in clover, and the plant yield was fully restored by the end of the third growing season. The content of oxidative enzymes in clover leaves was 2-10 times higher than in ryegrass. Biological activity of soil planted with clover was 1.5-2 times higher correlating with the biochemical parameters of plants. Higher basal respiration in soil planted with clover corresponded to the enhanced oil biodegradation. The differences in the carbon of oil products between soils planted with clover and ryegrass appeared at the end of the third growing season at high doses of oil (5 and 10Lm-2).

Bioremediation of Crude Oil Contaminated Soil Using Pig Droppings and Bone Char

Oil extraction operations as well as equipment failure and infrastructure vandalism have caused serious environmental pollution with crude oil spills world-wide. The remediation of the polluted sites is an environmental problem beckoning for solution. In this study, the possibility of pig droppings and pig bone char mixture (biostimulant) to stimulate and optimize crude oil biodegradation in soil was investigated. Exactly 500g of loamy soil was spiked with 3% (w/w) of crude oil. The spiked soil was amended with varying percentage mixtures of the biostimulant and labelled A – E. The spiked soil without biostimulant served as the Control. Each experiment was setup in six (6) replicates, carried out for six weeks, and destructively sampled and analysed on a weekly basis. The removal efficiencies of the biostimulated and unbiostimulated soils were observed to range from 66.70 to 86.70% and 3.69%, respectively. The biodegradation first-order rate constants ranged from 0.1978 to 0.3391wk-1 and 0.0050wk-1 for the biostimulated and unbiostimulated soils, respectively. Optimum removal of total petroleum hydrocarbon (TPH) was observed for biostimulated soil C comprising 50% bone char and 50% pig droppings. Results from biostimulated soils A, B, D and E indicated that pig droppings is a more effective biostimulant than pig bone char. A first-order kinetic model adequately predicted the removal of TPH with the optimum biostimulant. It is concluded that using agro-organic waste materials such as pig droppings and pig bone char in a ratio of 1:1 can offer a simple, effective, inexpensive and environmentally friendly solution to the problem of soil contamination with crude oil.

Transformation of Heavy Balakhani Oil Hydrocarbons in the Course of Oil Biodegradation in Soil

Changes in the composition of heavy Balakhani oil in the course of its biodegradation in soil were studied. The ability of microorganisms isolated from oil-contaminated soils to degrade petroleum products of various degrees of condensation (petroleum and its hexane, benzene, and alcohol–benzene fractions) was evaluated. The ways of biological oxidation of heavy oil by hydrocarbon-oxidizing microorganisms were investigated. It was found that the process of biological oxidation of the test oil contributed to dewaxing and aromatization and increased oil oxidation level due to an increase in oxygen-containing groups.

Effect of soil water content on heavy mineral oil biodegradation in soil

We investigated the limits and extent of heavy mineral oil biodegradation at different soil water levels and evaluated soil biological activity with regard to its usefulness for monitoring bioremediation processes in a soil contaminated with aged heavy mineral oil. To examine the effects of soil water content on heavy mineral oil biodegradation, a bench-scale investigation was conducted with different water levels (30, 50, and 80% water holding capacity) over a 105 day testing period. During the experiment, hydrocarbon concentration and microbial activity were monitored. At the end of the experiment (105 days), the initial level of contamination of 7858 ± 343 mg kg−1 was reduced to 4607 ± 290 mg kg−1 in soil with 30% water holding capacity (WHC), whereas only 28% of the hydrocarbons were eliminated in soils with 50 and 80% WHC. The hydrocarbon degradation rates declined with time, with 42% of the initial concentration of hydrocarbons remaining at the end of the experiment. The aged heavy mineral oil biodegradation process could be effectively monitored by soil biological parameters. There were significant correlations between the hydrocarbon concentration and selected biological parameters (soil respiration, dehydrogenase). Oxygen diffusion was inversely related to the soil water content. This affects hydrocarbon degradation and microbial activity. It is imperative to maintain a moderately low soil water content to maintain the effectiveness of bioremediation. Soil biological methods should complement chemical methods when assessing the success of bioremediation process.

Application of bacterial biosurfactants for enhanced removal and biodegradation of diesel oil in soil using a newly isolated consortium

Abstract One of the major environmental problems today is hydrocarbon contamination resulting from the activities related to the petrochemical industry. Bioremediation, involving the use of microorganisms to detoxify or remove pollutants is the most interesting strategy for hydrocarbon contamination depollution. In this aim, diesel oil biodegradation in soil was studied by four hydrocarbon degrading bacteria. A lipopeptide biosurfactant produced by Bacillus subtilis SPB1, confirmed to increase diesel mobility, was tested to increase diesel biodegradation along with co-inoculation with two biosurfactant producing strains. Culture studies revealed the enhancement of diesel biodegradation by the selected consortium with the addition of SPB1 lipopeptide and in the cases of co-inoculation by biosurfactant producing strain. In fact, an improvement of about 12.19% and 15.35% of diesel degradation were registered in the presence of 0.1% lipopeptide biosurfactant and when culturing B. subtilis SPB1 strain with the isolated consortium, respectively. Furthermore, the best improvement; evaluated to about 32.67% for soil contaminated with diesel was recorded when using the consortium cultured with B. subtilis SPB1 and Acinetobacter radioresistens RI7 strains. Gas phase chromatography analyses were correlated with the gravimetric evaluation of the residual hydrocarbons. Results suggested the potential applicability of the selected consortium along with the ex-situ and in-situ added biosurfactant for the bioremediation of diesel contaminated water and soil.

Enhanced crude oil biodegradation in soil via biostimulation

ABSTRACTResearch on feasible methods for the enhancement of bioremediation in soil contaminated by crude oil is vital in oil-exporting countries such as Kuwait, where crude oil is a major pollutant and the environment is hostile to biodegradation. This study investigated the possibility of enhancing crude oil bioremediation by supplementing soil with cost-effective organic materials derived from two widespread locally grown trees, Conocarpus and Tamarix. Amendments in soils increased the counts of soil microbiota by up to 98% and enhanced their activity by up to 95.5%. The increase in the biodegradation of crude oil (75%) and high levels of alkB expression substantiated the efficiency of the proposed amendment technology for the bioremediation of hydrocarbon-contaminated sites. The identification of crude-oil-degrading bacteria revealed the dominance of the genus Microbacterium (39.6%), Sphingopyxis soli (19.3%), and Bordetella petrii (19.6%) in unamended, Conocarpus-amended, and Tamarix-amended contaminated soils, respectively. Although soil amendments favored the growth of Gram-negative bacteria and reduced bacterial diversity, the structures of bacterial communities were not significantly altered.

New high-efficiency carbon-silica sorbent

Carbon-silica sorbent containing onion-like structures and simultaneously having sorption properties of both carbons and silicates was produced by carbonization of a mixture of silica sapropel and hydrolytic lignin at 20–700°C. The sorption characteristics of the sorbent with respect to radioactive nuclides (90Sr, 90Y, 137Cs, 232Th, 238U, 239Pu) and oil were determined. It was shown that the carbon-silica sorbent accelerates the biodegradation of oil in soil.

Electrokinetic Transport of Oil-Degrading Bacteria in Saturated Oil-Contaminated Soil

In this study, three bio-electrokinetic remediation experiments were carried out to study the external delivery of oil-degrading bacteria by electrokinetics and enzyme activities in saturated soil. Results showed that the oil-degrading bacteria could efficiently transport to the saturated oil-contaminated soil by electrophoresis and/or electroosmosis. Bacterial population increased from 6.02-7.75 log (CFU/g) in the control experiment to 8.53-12.83 log (CFU/g) after external bacterial delivery. Under unidirectional operation, the bacterial populations near the electrodes were lower than those in the middle of the soil as a result of unfavorable pH environments. In bidirectional experiment BEK-B, a relatively low bacterial population in the middle of the soil was observed after the experiment. The activities of catalase, polyphenol oxidase, and dehydrogenase have similar trends with bacterial population in the soil, indicating a good relation between the three enzymes and oil biodegradation of oil in soil.

Comprehensive GC2/MS for the monitoring of aromatic tar oil constituents during biodegradation in a historically contaminated soil

The constituents of tar oil comprise a wide range of physico-chemically heterogeneous pollutants of environmental concern. Besides the sixteen polycyclic aromatic hydrocarbons defined as priority pollutants by the US-EPA (EPA-PAHs), a wide range of substituted (NSO-PAC) and alkylated (alkyl-PAC) aromatic tar oil compounds are gaining increased attention for their toxic, carcinogenic, mutagenic and/or teratogenic properties. Investigations on tar oil biodegradation in soil are in part hampered by the absence of an efficient analytical tool for the simultaneous analysis of this wide range of compounds with dissimilar analytical properties. Therefore, the present study sets out to explore the applicability of comprehensive two-dimensional gas chromatography (GC²/MS) for the simultaneous measurement of compounds with differing polarity or that are co-eluting in one-dimensional systems. Aerobic tar oil biodegradation in a historically contaminated soil was analyzed over 56 days in lab-scale bioslurry tests. Forty-three aromatic compounds were identified with GC²/MS in one single analysis. The number of alkyl chains on a molecule was found to prime over alkyl chain length in hampering compound biodegradation. In most cases, substitution of carbon with nitrogen and oxygen was related to increased compound degradation in comparison to unalkylated and sulphur- or unsubstituted PAH with a similar ring number.The obtained results indicate that GC²/MS can be employed for the rapid assessment of a large variety of structurally heterogeneous environmental contaminants. Its application can contribute to facilitate site assessment, development and control of microbial cleanup technologies for tar oil contaminated sites.

Biodegradation of crude oil in soil using chicken manure

To investigate enhancement of crude oil biodegradation by adding microbes to the contaminated soil, chicken manure was put into oil-polluted soil (at 10% v/w pollution level). In the soil amended with chicken manure, 72.5% of the crude oil was degraded, whereas only 52.7% of same oil was degraded in the unamended soil. The remedied soil contains 1.4 × 106 CFU g−1 crude oil-degrading bacteria, and 1.1 × 108 CFU g−1 aerobic heterotrophs. The crude oil-utilising bacteria were identified as species of Pseudomonas, Proteus, Enterobacter, Bacillus and Micrococcus. Chicken manure is therefore promising for crude oil pollution remediation.

Naphthenic acids as indicators of crude oil biodegradation in soil, based on semi‐quantitative electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

Crude oil contaminated soil cores were collected from a basin that contained oily solids left from three decades of oil production. Hydrocarbon biomarker analyses revealed that the soil extracts were moderately biodegraded compared with the non-degraded source oil. The degree of biodegradation also decreased with core depth (7 cm to 1 m). These data were correlated to compositional changes observed in acidic NSO-compounds that were selectively ionized and mass resolved by negative ion electrospray Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). Among the NSO-compounds ionized, the increase in naphthenic acid concentration (e.g., acyclic and alicyclic carboxylic acids) best correlated with the increase in biodegradation (e.g., from non-degraded to moderately degraded) as determined by the hydrocarbon biomarker analyses. The most biodegraded surface extracts (7 cm) exhibited an 80% increase in the abundance of acids relative to the source oil. Use of an internal standard allowed the semi-quantitative determination of the total naphthenic acid concentration, which decreased significantly (P < 0.05) with soil depth. Furthermore, the shift to higher double bond equivalents (DBEs), from acyclic to alicyclic acids, indicated that the increase in acids in the soil extracts was predominantly due to biotic processes. This work demonstrates the potential of ESI FT-ICR MS as a semi-quantitative tool to monitor the production of naphthenic acids during crude oil biotransformation in the environment.

Stimulated Biodegradation of Crude Oil in Soil Amended with Periwinkle Shells

The potential of periwinkle shell (PS) in enhancing the microbial break down of crude oil spilled in soil were studied. The results revealed that the counts of crude oil degrading bacteria in oil-polluted soil fortified with PS were higher than the counts in unfortified soil. The rates and total extent of crude oil biodegradation in the soil were stimulated by the amendment. About 43.4 percent of crude oil was degraded in unfortified soil after 16 days as compared to 70.1 percent oil biodegradation, which occurred in PS fortified soil during the same period. These values were significantly (P>0.05) different from each other. Amendment of the soil with PS also raised the pH of the soil from acidic to alkaline range. The crude oil degrading microorganisms identified in PS amended soil were of the genus Pseudomonas, Bacillus, Micrococcus, Acinetobacter, Penicillium, Aspergillus, Mucor and Rhizopus. Similarly, Pseudomonas, Bacillus, Micrococcus, Mucor, Aspergillus and Penicillium were identified as crude oil degrading microorganisms in unamended soil. The bacteria formed either stable or unstable emulsions, suggesting that the organisms produce surface-active agents (biosurfactants) during the biodegradation process. The results of this study indicate that PS can be used in reclaiming oil-polluted soil.