Assessing the half-life and degradation kinetics of aliphatic and aromatic hydrocarbons by bacteria isolated from crude oil contaminated soil.

Pollution from the oil industries and refineries has worsened various environmental compartments. In this study, indigenous oil degrading bacteria were isolated from crude oil obtained from an Oil and Natural Gas Corporation (ONGC) asset in Ankleshwar, Gujarat, India. Based on 16S rRNA phylogeny, they were identified as Pseudomonas boreopolis IITR108, Microbacterium schleiferi IITR109, Pseudomonas aeruginosa IITR110, and Bacillus velezensis IITR111. The strain IITR108, IITR109, IITR110, and IITR111 showed 80-89% and 71-78% degradation of aliphatic (C8-C40) and aromatic (4-5 ring) hydrocarbons respectively in 45 d when supplemented with 3% (v/v) waste crude oil. When compared to individual bacteria, the consortium degrades 93.2% of aliphatic hydrocarbons and 85.5% of polyaromatic hydrocarbons. It was observed that the total aliphatic and aromatic content of crude oil 394,470 µg/mL and 47,050 µg/mL was reduced up to 9617.75 µg/mL and 4586 µg/mL respectively in 45 d when consortium was employed. The rate kinetics analysis revealed that the biodegradation isotherm followed first order kinetics, with a linear correlation between concentration (hydrocarbons) and time intervals. The half-life of aliphatic (C8-C40) and aromatic hydrocarbons ranged from 200 to 453 h and 459-714 h respectively. All the bacteria efficiently produced catabolic enzymes such as alkane monooxygenase, alcohol dehydrogenase, and lipase during the degradation of crude oil. These findings indicated that the bacterial consortium can be a better candidate for bioremediation and reclamation of aliphatic and aromatics hydrocarbon contaminated sites.

Investigation of the effect of refining on the presence of targeted mineral oil aromatic hydrocarbons in coconut oil.

The goal of this work was to investigate the impact of refining on coconut oil particularly on the most toxicologically relevant fraction of the mineral oil aromatic hydrocarbon (MOAH) contamination, namely the fraction composed by the three to seven aromatic rings. A fully integrated platform consisting of a liquid chromatography (LC), a comprehensive multidimensional gas chromatography (GC) (LC-GC × GC) and flame ionization detector (FID) was used to obtained a more detailed characterization of the MOAH sub-classes distribution. The revised EN pr 16995:2017-08 official method was used for preparing the samples, both with and without the auxiliary epoxidation step. Crude coconut oil was spiked with different MOAH standards, namely naphthalenes, alkylated naphthalenes, benzo(a)pyrene, and its alkylated homologues. Refining was modelled by deodorization at 230 °C, stripping with 10 kg/h of steam under 1 mbar vacuum for 3 h. Complete removal of the naphthalenes and reduction of more than 98.8% of the benzo(a)pyrenes was observed. Epoxidation had a significant impact on the MOAH fraction with more than three rings, but with a high dependency on the sample matrix, being significantly less evident in the refined samples than in the crude ones.

Automated workflow utilizing saponification and improved epoxidation for the sensitive determination of mineral oil saturated and aromatic hydrocarbons in edible oils and fats.

Refined edible oils and fats are known to contain olefins resisting the typical epoxidation used for the sample preparation of mineral oil saturated and aromatic hydrocarbons (MOSH and MOAH). These olefins can be misinterpreted as MOAH and are therefore an important reason for inconsistent results between laboratories. Collaborative trials confirm this assumption for low MOAH contents near the quantitation limits regularly. In the scope of this work, a new epoxidation approach was developed. Persistent olefins in refined oils could be successfully epoxidized with performic acid. The reaction kinetics was investigated using model substances for biogenic olefins and MOAH. It was rationalized why certain olefins resist epoxidation and which MOAH can potentially get lost. A prominent peak cluster in the MOAH fraction of refined palm oils could be identified by means of GC-MS and explained why it cannot be epoxidized. Based upon this, an automated and streamlined workflow for sample preparation and analysis was composed tackling major problems identified in previously published methods. Optimized and miniaturized saponification, extraction, epoxidation, and enrichment paired with online LC-GC-FID led to a robust method that was tested and validated for edible oils and fats (RSDR < 7% for MOSH and MOAH at values of 14.9 and 2.1 mg/kg, respectively). Due to increased sample amount and minimized blank values, quantitation limits below 1 mg/kg for MOSH and MOAH were achieved. The trueness of the method was verified by analyzing collaborative trial samples.

Structural identification of sour compounds in wine and tea by ambient ionization mass spectrometry according to characteristic product ion and neutral loss.

Sourness is an important food taste for human. A rapid, accurate method was used to generalize the structure similarity and diversity of sour compounds. Based on the product ion and neutral loss of sour compounds, ambient ionization techniques combined with quadrupole-Orbitrap mass spectrometry (AI-Q-Orbitrap) was employed. According to the behavior of sour compounds in the process of high collision dissociation (HCD) of MS/MS, three fragmentation pathway schemes were proposed: (1) charge-driven fragmentation and CO2 loss, (2) six-membered ring rearrangement and Cα-Cß cleavage, and (3) elimination rearrangement and H2O, CO2 and CO loss in succession. Besides, structure information about characteristic product ions and characteristic neutral losses was summarized. Finally, multi-class sour compounds including monoacids, diacids, polyacids and phenolic acids in wine and tea were identified and compared. Therefore, sour compounds and their structure information can be determined by AI-MS based on characteristic product ion and neutral loss.

A new and effective evaluation method for Radix Gentianae Macrophyllae herbs based on 2-phenylethyl ß-d-glucopyranoside, 2-methoxyanofinic acid and gentioxepine by UPLC-QTOF-MS exploring and HPLC-DAD quantification.

Radix Gentianae Macrophyllae (RGM) is a traditional Chinese medicine belonging to the Gentiana genus and including four species of herbs. Owing to the lack of characteristic constituents, it is difficult to discriminate RGMs of different origins or even differentiate between herbs in the same genus. The current research aimed to explore the characteristic aromatic compounds, verify their significance in distinguishing different origins of RGM herbs and provide a simple and effective quality evaluation method. A selective extraction method was developed for noniridoid compounds and the extract was then subjected to UPLC-QTOF-MS analysis to obtain the RGM-MS ion pair database for noniridoid components. An HPLC-DAD quantitative analysis method was further developed based on characteristic aromatic compounds (2-phenylethyl ß-d-glucopyranoside, 2-methoxyanofinic acid and gentioxepine) after the ion screening in the MS database. By means of principal component analysis and hierarchical clustering analysis analysis, the significant relationship between aromatic compounds contents and different species of RGM was revealed. As a result, the significance of 2-phenylethyl ß-d-glucopyranoside, 2-methoxyanofinic acid and gentioxepine in distinguishing four species of RGM herbs was verified and a sensitive and reproducible HPLC-DAD method was established using these markers, which can be used for the classification and quantitative analysis of RGMs.

Increasing phenolic and aromatic compounds extraction and maximizing liking of lemon verbena (Aloysia triphylla) infusions through the optimization of steeping temperature and time.

Herbal infusions are a new emerging trend among consumers, appearing in the market in many different forms. Due to intense competition, the commercial success of herbal infusions largely depends on flavour. The identification of the best combinations of steeping time and water temperature for the preparation of Aloysia triphylla infusions using a central composite design and response surface methodology was performed. The procedure aimed to maximize its antioxidant activity, phenolic and aromatic compounds, and consumers' liking of the infusions. The antioxidant activity and phenolic content were evaluated using the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid radical cation) method and the Folin-Ciocalteu procedure. The analysis of aromatic compounds was performed based on the method of terpenic compounds. Sensory evaluation encompassed overall liking using a 9-point hedonic scale. Antioxidant activity and extraction of most phenolic compounds was higher for longer steeping times and higher temperatures, with some presenting a contrasting effect due to degradation at higher temperatures for longer steeping times. Results for terpenic compounds showed similar contrasting patterns. Based on the quadratic response surface, it was possible to predict the maximum overall liking for lemon verbena infusions prepared by brewing for 6 min at 96 ℃. Under such conditions, extraction of bioactive compounds was kept at a high level, close to the maximum attainable, while reducing the extraction of bitter compounds. These results are considered of great importance for the development of premium infusions from organic lemon verbena leaves.

Pulsed elution modulation for on-line comprehensive two-dimensional liquid chromatography coupling reversed phase liquid chromatography and hydrophilic interaction chromatography.

In this work, a reversed phase liquid chromatography (RPLC) coupling to hydrophilic interaction chromatography (HILIC) system has been constructed, combining with pulsed elution reversed phase liquid chromatography (PE-RPLC) and HILIC to comprehensively analyze P. ginseng root extract, which is rich in saponins. By the application of pulsed elution (PE) modulation technique, the proposed RPLC × HILIC system allows the chromatographic separation to be optimized independently in both dimensions. In the first dimension (1D), PE modulation is achieved by the separation of a complex mixture, such as P. ginseng root extract, with a PE gradient. This PE gradient contains a set of pulses where the solvent strength increases gradually. Thus, the modulation of 1D eluent is realized by stepwise-pulse fractionation, rather than by a traditional two-dimensional interface. Furthermore, the number of fractions and the fractionated period can be regulated independently, which leads to independent adjustment of the separation cycle in the second dimension (2D) separation without the loss of D1 separation efficiency. To overcome the inherent solvent incompatibility of RPLC × HILIC, we introduced a newly developed trapping interface, equipped with bypass. The result indicates excellent separation of saponins in P. ginseng root extract. Compared with the traditional modulation method, the proposed RPLC × HILIC system has extreme flexibility, those modulation time could be regulated in a large range without re-optimizing the 1D PE gradient. Worthily mentioned, the proposed RPLC × HILIC system shows excellent orthogonality, and 20% more peaks could be obtained with current method compared to the traditional value based modulation method. Independent regulation of both dimensions could enable the proposed modulation method to be widely applied for complex samples analysis in ordinary laboratory.

Biodegradation and detoxification of aliphatic and aromatic hydrocarbons by new yeast strains.

Seeking new efficient hydrocarbon-degrading yeast stains was the main goal of this study. Because microorganisms are greatly affected by the environmental factors, the biodegradation potentiality of the microorganisms varies from climatic area to another. This induces research to develop and optimize the endemic organisms in bioremediation technology. In this study, 67 yeast strains were tested for their growth potentiality on both aliphatic and aromatic hydrocarbons. The most efficient six strains were identified using sequence analysis of the variable D1/D2 domain of the large subunit 26S ribosomal DNA. The identity of these strains was confirmed as Yamadazyma mexicana KKUY-0160, Rhodotorula taiwanensis KKUY-0162, Pichia kluyveri KKUY-0163, Rhodotorula ingeniosa KKUY-0170, Candida pseudointermedia KKUY-0192 and Meyerozyma guilliermondii KKUY-0214. These species are approved for their ability to degrade both aliphatic and aromatic hydrocarbons for the first time in this study. Although, all of them were able to utilize and grow on both hydrocarbons, Rhodotorula taiwanensis KKUY-0162 emerged as the best degrader of octane, and Rhodotorula ingeniosa KKUY-170 was the best degrader of pyrene. GC-MS analysis approved the presence of many chemical compounds that could be transitional or secondary metabolites during the utilization of the hydrocarbons. Our results recommend the application of these yeast species on large scale to approve their efficiency in bioremediation of oil-contamination of the environment. Using these yeasts, either individually or in consortia, could offer a practical solution for aquatic or soil contamination with the crude oil and its derivatives in situ.

Comprehensive two-dimensional gas chromatography-mass spectrometry of complex mixtures of anaerobic bacterial metabolites of petroleum hydrocarbons.

Anaerobic biotransformation of petroleum hydrocarbons is an important alteration mechanism, both subsurface in geological reservoirs, in aquifers and in anoxic deep sea environments. Here we report the resolution and identification, by comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS), of complex mixtures of aromatic acid and diacid metabolites of the anaerobic biodegradation of many crude oil hydrocarbons. An extended range of metabolites, including alkylbenzyl, alkylindanyl, alkyltetralinyl, alkylnaphthyl succinic acids and alkyltetralin, alkylnaphthoic and phenanthrene carboxylic acids, is reported in samples from experiments conducted under sulfate-reducing conditions in a microcosm over two years. The range of metabolites identified shows that the fumarate addition mechanism applies to the alteration of hydrocarbons with up to C8 alkylation in monoaromatics and that functionalisation of up to three ring aromatic hydrocarbons with at least C1 alkylation occurs. The GC×GC-MS method might now be applied to the identification of complex mixtures of metabolites in samples from real environmental oil spills.

Removal of NAPL from columns by oxidation, sparging, surfactant and thermal treatment.

In this paper, four treatment techniques commonly applied to Volatile Organic Compounds (VOC) removal from soil are compared in column experiments with pure sand containing a residual Light Non-Aqueous Phase Liquid (L-NAPL) contamination. Oxidation is tested through the injection of Fenton reagent, with persulfate, and combined with sparging with the injection of ozone. Surfactant treatment was conducted at low flow rates with Tween®80. Sparging was conducted by air injection but at a low flow rate of 1 mL min-1. Finally several columns were thermally treated at a temperature of 80 °C. The results showed high removal (>90%) for all techniques used, although only thermal treatment on BTEX (Benzene, Toluene, Ethylbenzene and Xylenes) reached 100% efficiency. The main limiting factors of each technique were: (i) for oxidation, the solubility of the substance limited the removal; (ii) for surfactant both the solubility in the surfactant and the type of surfactant are important; (iii) for sparging, the main factors are contaminant vapor pressure and porous media grain size; (iv) for thermal treatment, the limitation arises from the contaminant vapor pressure and the medium hydraulic conductivity. A comparison with literature data shows that the results are consistent with most of the studies conducted on one technique.

Determination of mineral oil aromatic hydrocarbons in edible oils and fats by online liquid chromatography-gas chromatography-flame ionization detection - Evaluation of automated removal strategies for biogenic olefins.

The determination of mineral oil aromatic hydrocarbons (MOAH) in foodstuffs gained in importance over the last years as carcinogenicity cannot be excluded for certain MOAH. The existence of olefins in foodstuffs, such as edible oils and fats, can be problematic for the determination of MOAH by LC-GC-FID. Removal of these interfering substances by HPLC based on polarity differences is not possible. During gas chromatographic separation heavily overloaded peaks are observed rendering the detection of small mineral oil contaminations almost impossible. Therefore, removal of these olefins is necessary before subjection of the sample to LC-GC-FID. Epoxidation of olefins to increase their polarity proved to be a valuable tool in the past. Precision and trueness of the results as shown in a collaborative trial, however, are relying on exact reaction conditions. Additionally, it is known that certain MOAH are oxidized during epoxidation and therefore get lost. In the scope of this work, hydroboration, bromohydrin reaction, and epoxidation were examined for their potential for derivatization of unsaturated hydrocarbons with increased robustness and higher recovery of MOAH. Epoxidation by meta-chloroperoxybenzoic acid (mCPBA) delivered the best removal of olefins. Factors influencing this reaction were enlightened. Adaption of the reaction conditions and time-controlled automation increased the recovery of polycyclic MOAH. Good precision (RSDr <1.5%) and recovery (95-102%) for MOAH were also observed for sunflower and olive oils spiked with a lubricating mineral oil (at 24.5mg/kg of MOAH). The trueness of the method was verified by analyzing collaborative trial samples.

Occurrence and distribution of monocyclic aromatic hydrocarbons (BTEX) and the impact on macrobenthic community structure in Lagos lagoon, Nigeria.

The widespread distribution of petroleum products arising from the rapid growth of the petroleum industry in Nigeria has resulted in the pollution of the environment through oil spills involving leakages from tankers, pipelines, tank farms, and dumping of waste petroleum products. The impacts and distribution of major toxic components (benzene, toluene, ethylbenzene, and xylene (BTEX)) of petroleum products in water and sediment samples collected from sampling stations in the Lagos lagoon was investigated over a 2-year period (February 2009-July 2010). The distribution of benthic communities in the different sampling stations of the Lagos lagoon was assessed. The determination of hydrocarbon levels in the samples showed that the levels of total hydrocarbon content (THC) in the water samples around the Atlas Cove and Apapa were high with values ranging from 2.03 to 31.38 mg/l and 4.04 to 22.89 mg/l, respectively. The highest value of total BTEX in the lagoon sediment was also recorded in the Apapa station (450.53 µg/kg), where oil depots and tank farm facilities are located. The study of the macrobenthic community structure showed that the species richness ranged from 1.57 to 2.02 in the reference station, Unilag, while in the Atlas Cove, Iddo, and Apapa stations, it ranged from 1.80 to 2.89, 1.95 to 3.03, and 1.86 to 2.95, respectively. The highest number of organisms (183) was recorded in the reference stations, while the least number (46) was recorded in Apapa. The main hydrocarbon pollution indicator species identified in the impacted aquatic stations were Nais eliguis and Heteromastus filiformis. The levels of hydrocarbon observed in the aquatic environment showed that there is widespread contamination as a result of petroleum product importation, storage, and distribution. The assessment of the monocyclic aromatic hydrocarbon and benthic community will therefore provide important tools for early detection, diagnosis, and management of hydrocarbon pollution in the Lagos lagoon.

Characterization of sulfur and nitrogen compounds in Brazilian petroleum derivatives using ionic liquid capillary columns in comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection.

Diesel and naphtha samples were analyzed using ionic liquid (IL) columns to evaluate the best column set for the investigation of organic sulfur compounds (OSC) and nitrogen(N)-containing compounds analyses with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry detector (GC×GC/TOFMS). Employing a series of stationary phase sets, namely DB-5MS/DB-17, DB-17/DB-5MS, DB-5MS/IL-59, and IL-59/DB-5MS, the following parameters were systematically evaluated: number of tentatively identified OSC, 2D chromatographic space occupation, number of polyaromatic hydrocarbons (PAH) and OSC co-elutions, and percentage of asymmetric peaks. DB-5MS/IL-59 was chosen for OSC analysis, while IL59/DB-5MS was chosen for nitrogen compounds, as each stationary phase set provided the best chromatographic efficiency for these two classes of compounds, respectively. Most compounds were tentatively identified by Lee and Van den Dool and Kratz retention indexes, and spectra-matching to library. Whenever available, compounds were also positively identified via injection of authentic standards.

Indirect methods of dried sewage sludge contamination assessments.

Thermal conversion (combustion, co-combustion, gasification and pyrolysis) appears to be the most promising alternative for sewage sludge management in the future. Nevertheless, safe and ecological usage of sewage sludge as a fuel requires information about their contamination. The aim of this paper is to present the photoacoustic spectroscopy (PAS) as a good method for contamination assessments of dried sewage sludge. Two types of granular sewage sludge: Sewage sludge 1 (SS1) taken from Polish wastewater treatment plant operating in the mechanical-biological system and sewage sludge 2 (SS2) taken from mechanical-biological-chemical wastewater treatment plant with phosphorus precipitation were analysed. The spectrophotometer FTIR Nicolet 6700 equipped with photoacoustic cell (Model 300, MTEC, USA) was used. The comparison with the most popular analytical methods (GC-MS) was also done. The results of PAS studies confirm the difference between the SS1 and SS2 which is in agreement with the GC-MS analysis. Higher absorbance was observed at each wavelength characteristics for the oscillator of chemical moieties for the SS1 with respect to the SS2.

Petroleum biomarkers as tracers of Exxon Valdez oil.

Over the past quarter century, petroleum biomarkers have persisted in sequestered Exxon Valdez oil in Prince William Sound and the Gulf of Alaska (USA), and hence the oil has remained identifiable. These biomarkers are molecular fossils derived from biochemicals in previously living organisms. Novel pattern matching indicated the presence of Alaska North Slope crude oil (ANSCO) over the entire observation period at most sites (7 of 9) and distinguished this source from several other potential sources. The presence of ANSCO was confirmed with Nordtest forensics, demonstrating the veracity of the new method. The principal advantage of the new method is that it provides sample-specific identification, whereas the Nordtest approach is based on multisample statistics. Biomarkers were conserved relative to other constituents, and thus concentrations (per g oil) in initial beach samples were greater than those in fresh oil because they were lost more slowly than more labile oil constituents such as straight-chain alkanes and aromatic hydrocarbons. However, biomarker concentrations consistently declined thereafter (1989-2014), although loss varied substantially among and within sites. Isoprenoid loss was substantially greater than tricyclic triterpane, hopane, and sterane loss. Environ Toxicol Chem 2016;35:2683-2690. © 2016 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. This article is a US government work and as such, is in the public domain in the United States of America.

Determination of the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants.

A method was developed to determine the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants; a survey was also conducted of commercial lubricants. Hydrocarbons in lubricants were separated from the matrix components of lubricants using a silica gel solid phase extraction (SPE) column. Normal-phase liquid chromatography (NPLC) coupled with an evaporative light-scattering detector (ELSD) was used to determine the aromatic hydrocarbon to total hydrocarbon ratio. Size exclusion chromatography (SEC) coupled with a diode array detector (DAD) and a refractive index detector (RID) was used to estimate carbon numbers and the presence of aromatic hydrocarbons, which supplemented the results obtained by NPLC/ELSD. Aromatic hydrocarbons were not detected in 12 lubricants specified for use for incidental food contact, but were detected in 13 out of 22 lubricants non-specified for incidental food contact at a ratio up to 18%. They were also detected in 10 out of 12 lubricants collected at food factories at a ratio up to 13%. The centre carbon numbers of hydrocarbons in commercial lubricants were estimated to be between C16 and C50.

Application of nitrate to enhance biodegradation of gasoline components in soil by indigenous microorganisms under anoxic condition.

Anaerobic/anoxic biodegradation of hydrocarbons offers an attractive approach to the removal of these compounds from polluted environments such as aquifers, aquatic sediments, submerged soils and subsurface soils. The application of nitrate was investigated to accelerate the degradation of gasoline components such as mono-aromatic hydrocarbons and total petroleum hydrocarbons (TPH) in soil by indigenous microorganisms under anoxic condition. The addition of nitrate had little effect on the degradation of mono-aromatic hydrocarbons m- & p-xylene, o-xylene, sec-butylbenzene and 1,2,4-trimethylbenzene, but facilitated the degradation of TPH (C6-C12) and mono-aromatic hydrocarbons toluene and ethylbenzene markedly. Furthermore, the more nitrate added, the higher the percentage of toluene, ethylbenzene and TPH (C6-C12) degraded after 180 days of anoxic incubation. Microorganisms capable of degrading toluene, ethylbenzene and TPH (C6-C12) with nitrate as the electron acceptor under anaerobic/anoxic condition are composed predominantly of Alpha-, Beta-, Gamma- or Delta-proteobacteria. Beta- and Gamma-proteobacteria were the main components of indigenous microorganisms, and accounted for 83-100% of the total amount of indigenous microorganisms in soil used in this study. Furthermore, the total amount of indigenous microorganisms increased with nitrate added. The addition of nitrate stimulated the growth of indigenous microorganisms, and therefore facilitated the degradation of toluene, ethylbenzene and TPH (C6-C12).

LC-MS-based metabolite profiling of methanolic extracts from the medicinal and aromatic species Mentha pulegium and Origanum majorana.

INTRODUCTION: There has been increasing interest dedicated to the phenolic compounds with a view to their antioxidant and healthy properties. Recent studies have focused on plants from the Lamiaceae family with special interest in phenolic compounds antioxidant potential. OBJECTIVE: The metabolite profile of methanolic extracts from two Lamiacea medicinal plants was investigated. MATERIALS AND METHODS: Mentha pulegium and Origanum majorana methanolic extracts were analysed using reversed-phase ultra-high-performance liquid chromatography (RP-UHPLC) coupled to electrospray ionisation quadrupole time-of-flight mass spectrometry (ESI-QTOF-MS) detection in the negative ion mode. RESULTS: A total of 85 metabolites were characterised from different families, such as organic acids and derivatives, amino acids and derivatives, nucleosides, phenolic compounds as well as other polar metabolites, by using the MS and MS/MS information provided by the QTOF-MS. However, the total phenols and flavonoids were also quantified spectrophotometrically and they registered higher amounts in Mentha pulegium than in Origanum majorana extract. Gallocatechin was the major compound in M. pulegium extract whereas quercetin dimethyl ether, jaceidin and dihydrokaempferide were the major ones in O. majorana extract. CONCLUSION: The distribution of phenolic compounds in the methanolic extract showed a variation among studied plants. Mentha pulegium can be considered as a source of gallocatechin.

Tissue PAH, blood cell and tissue changes following exposure to water accommodated fractions of crude oil in alligator gar, Atractosteus spatula.

Alligator gar Atractosteus spatula acclimated to brackish water (9 ppt) were exposed to water accommodated fraction oil loadings (surrogate to Macondo Deepwater Horizon, northern Gulf of Mexico) of 0.5 and 4.0 gm oil/L tank water for 48 h. The surrogate oil was approximately 98% alkanes and alkynes and 2% petroleum aromatic hydrocarbons. The 2% petroleum aromatic hydrocarbons were predominately naphthalene. After 48 h, naphthalene levels in fish liver exposed to 0.5 or 4 gm oil/L were 547.79 and 910.68 ppb, while muscle levels were 214.11 and 253.84 ppb. There was a significant decrease in peripheral blood lymphocyte numbers and a significant reduction of granulocytes in the kidney marrow of the same fish. Tissue changes included hepatocellular vacuolization and necrosis, necrotizing pancreatitis, renal eosinophilia, and splenic congestion. After 7 days recovery, liver naphthalene levels decreased to 43.59 and 43.20 ppb, while muscle levels decreased to 9.74, and 16.78 ppb for oil exposures of 0, 0.5 or 4 g/L. In peripheral blood and kidney marrow, blood cell counts returned to normal. The severity of liver and kidney lesions lessened after 7 days recovery in non-oiled water, but splenic congestion remained in all gar.

Insight into unresolved complex mixtures of aromatic hydrocarbons in heavy oil via two-dimensional gas chromatography coupled with time-of-flight mass spectrometry analysis.

The aromatic hydrocarbon fractions of five crude oils representing a natural sequence of increasing degree of biodegradation from the Liaohe Basin, NE, China, were analyzed using conventional gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography (GC×GC). Because of the limited peak capability and low resolution, compounds in the aromatic fraction of a heavily biodegraded crude oil that were analyzed by GC-MS appeared as unresolved complex mixtures (UCMs) or GC "humps". They could be separated based on their polarity by GC×GC. UCMs are composed mainly of aromatic biomarkers and aromatic hydrocarbons with branched alkanes or cycloalkanes substituents. The quantitative results achieved by GC×GC-FID were shown that monoaromatic hydrocarbons account for the largest number and mass of UCMs in the aromatic hydrocarbon fraction of heavily biodegraded crude oil, at 45% by mass. The number and mass of diaromatic hydrocarbons ranks second at 33% by mass, followed by the aromatic biomarker compounds, triaromatic, tetraaromatic, and pentaaromatic hydrocarbons, that account for 10%, 6%, 1.5%, and 0.01% of all aromatic compounds by mass, respectively. In the heavily biodegraded oil, compounds with monocyclic cycloalkane substituents account for the largest proportion of mono- and diaromatic hydrocarbons, respectively. The C4-substituted compounds account for the largest proportion of naphthalenes and the C3-substituted compounds account for the largest proportion of phenanthrenes, which is very different from non-biodegraded, slightly biodegraded, and moderately biodegraded crude oil. It is inferred that compounds of monoaromatic, diaromatic and triaromatic hydrocarbons are affected by biodegradation, that compounds with C1-, C2-substituents are affected by the increase in degree of biodegradation, and that their relative content decreased, whereas compounds with C3-substituents or more were affected slightly or unaffected, and their relative content also increased. The varying regularity of relative content of substituted compounds may be used to reflect the degree of degradation of heavy oil. Moreover, biomarkers for the aromatic hydrocarbons of heavily biodegraded crude oil are mainly aromatic steranes, aromatic secohopanes, aromatic pentacyclotriterpanes, and benzohopanes. According to resultant data, aromatic secohopanes could be used as a specific marker because of their relatively high concentration. This aromatic compound analysis of a series of biodegraded crude oil is useful for future research on the quantitative characterization of the degree of biodegradation of heavy oil, unconventional oil maturity evaluation, oil source correlation, depositional environment, and any other geochemical problems.