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Biotechnology Journal Aug 2019During crude oil extraction, the reduction in temperature and pressure results in the precipitation of paraffin wax that contains 20-40 carbon chain hydrocarbons. The...
During crude oil extraction, the reduction in temperature and pressure results in the precipitation of paraffin wax that contains 20-40 carbon chain hydrocarbons. The paraffin wax may accumulate inside production tubes, pipelines, and processing facilities, and also in tankers during petroleum transportation. There are few bacterial strains that are able to degrade solid substrates. In the present study, the biodegradation of paraffin is evaluated using Rhodococcus erythropolis cells. This bacterium is able to grow using paraffin wax from an oil refinery plant as the sole carbon source. The cells grow as a thick biofilm over the solid substrate, make scale-like structures that increase the area of the initially smooth surface of paraffin, produce biosurfactants, and become more negatively charged than ethanol- or glucose-grown cells. When paraffin wax is supplied as microparticles, to increase the cell-substrate contact area and to simulate paraffin precipitation, the cells also adjust the composition of the fatty acids of the phospholipids of the cellular membrane to decrease its fluidity and paraffin biodegradation increases considerably. The study suggests that the phenotypic adaptation of R. erythropolis cells may be used to degrade paraffin wax under real conditions.
Topics: Adaptation, Biological; Biodegradation, Environmental; Biofilms; Cell Membrane; Hydrocarbons; Lipid Metabolism; Lipids; Microscopy, Electron, Scanning; Paraffin; Rhodococcus
PubMed: 31125157
DOI: 10.1002/biot.201800598 -
Meditsinskaia Sestra May 1969
Topics: Paraffin
PubMed: 5194165
DOI: No ID Found -
Fel'dsher I Akusherka Jan 1968
Topics: Nursing; Occlusive Dressings; Paraffin
PubMed: 5183957
DOI: No ID Found -
Applied and Environmental Microbiology Jan 2018Paraffinic -alkanes (>C) that are solid at ambient temperature comprise a large fraction of many crude oils. The comparatively low water solubility and reactivity of...
Paraffinic -alkanes (>C) that are solid at ambient temperature comprise a large fraction of many crude oils. The comparatively low water solubility and reactivity of these long-chain alkanes can lead to their persistence in the environment following fuel spills and pose serious problems for crude oil recovery operations by clogging oil production wells. However, the degradation of waxy paraffins under the anoxic conditions characterizing contaminated groundwater environments and deep subsurface energy reservoirs is poorly understood. Here, we assessed the ability of a methanogenic culture enriched from freshwater fuel-contaminated aquifer sediments to biodegrade the model paraffin -octacosane (CH). Compared with that in controls, the consumption of -octacosane was coupled to methane production, demonstrating its biodegradation under these conditions. was postulated to be an important CH degrader in the culture on the basis of its high relative abundance as determined by 16S rRNA gene sequencing. An identified gene (known to encode the α subunit of alkylsuccinate synthase) aligned most closely with those from other organisms. Quantitative PCR (qPCR) and reverse transcription qPCR assays for demonstrated significant increases in the abundance and expression of this gene in CH-degrading cultures compared with that in controls, suggesting -octacosane activation by fumarate addition. A metabolite analysis revealed the presence of several long-chain α,ω-dicarboxylic acids only in the CH-degrading cultures, a novel observation providing clues as to how methanogenic consortia access waxy hydrocarbons. The results of this study broaden our understanding of how waxy paraffins can be biodegraded in anoxic environments with an application toward bioremediation and improved oil recovery. Understanding the methanogenic biodegradation of different classes of hydrocarbons has important applications for effective fuel-contaminated site remediation and for improved recovery from oil reservoirs. Previous studies have clearly demonstrated that short-chain alkanes (
C) that comprise many fuel mixtures. Using an enrichment culture derived from a freshwater fuel-contaminated site, we demonstrate that the model waxy alkane -octacosane can be biodegraded under methanogenic conditions by a presumed phylotype. Compared with that of controls, we show an increased abundance and expression of the gene, which is known to be important for anaerobic -alkane metabolism. Metabolite analyses revealed the presence of a range of α,ω-dicarboxylic acids found only in -octacosane-degrading cultures, a novel finding that lends insight as to how anaerobic communities may access waxes as growth substrates in anoxic environments. Topics: Bacterial Proteins; Biodegradation, Environmental; Deltaproteobacteria; Paraffin; Petroleum Pollution; Phylogeny; RNA, Bacterial; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 29030441
DOI: 10.1128/AEM.01773-17 -
Physical Therapy Aug 1967
Topics: Baths; Paraffin
PubMed: 6076110
DOI: 10.1093/ptj/47.8.714 -
IARC Monographs on the Evaluation of... 1990
Review
Topics: Animals; Carcinogens; Carcinogens, Environmental; Chemical Phenomena; Chemistry; Female; Humans; Hydrocarbons, Chlorinated; Male; Mice; Paraffin; Rats
PubMed: 2197463
DOI: No ID Found -
Chemosphere Mar 2022Chlorinated paraffins (CPs) are industrial chemicals that have been primarily used in applications involving metalworking fluids. Among CPs, short-chain chlorinated...
Chlorinated paraffins (CPs) are industrial chemicals that have been primarily used in applications involving metalworking fluids. Among CPs, short-chain chlorinated paraffins (SCCPs) are a well-known environmental pollutant and are listed under Annex A of the Stockholm Convention on Persistent Organic Pollutants. CPs are alkanes substituted with chlorine atoms, and SCCPs are comprised of 10-13 carbon atoms. Reliable quantification of SCCPs is a critical issue because of the large number of SCCP isomers that are in use across multiple industries. Some interlaboratory comparisons of SCCP analyses have been conducted, and the reliability of these results was overwhelmingly determined as inferior to that of comparable PCB and dioxin analyses because of variations in the quality of commercial reagents that were employed as quantification standards. In order to address such inconsistencies, this study endeavored to prepare and evaluate a novel SCCP formulation as a candidate reference material for use as a reliable quantification standard. A subject trial study was hence performed to evaluate methods such as gas- and liquid-chromatography mass spectrometry (GC/MS and LC/MS) on sample matrices (without a clean-up process), and to subsequently elucidate the interpreted specifications for their candidacy as a reliable quantification standard. Results ultimately showed that the SCCP concentrations obtained from GC and LC were comparable. When the homologs reported by a subset of 14 separate laboratories were unified (excluding all results for Cl homologs), the carbon chain length profiles obtained from GC and LC were found to be similar; however, the overall chlorine homolog profiles did exhibit slight differences. Moreover, the results from high-resolution MS showed less variation than those from low-resolution MS. Thus, it was overarchingly determined that the deployment of this candidate reference material would serve as an effective mechanism for estimating the comparability of SCCP quantifications/evaluations of standard materials.
Topics: China; Environmental Monitoring; Environmental Pollutants; Hydrocarbons, Chlorinated; Paraffin; Reproducibility of Results
PubMed: 34752840
DOI: 10.1016/j.chemosphere.2021.132783 -
Chemosphere Dec 2022A new simple method for chlorine percentage calculations (method C), from proton nuclear magnetic resonance (H NMR) spectroscopy, has been established and applied to an...
A new simple method for chlorine percentage calculations (method C), from proton nuclear magnetic resonance (H NMR) spectroscopy, has been established and applied to an industrial chlorinated paraffin (CP) mixture and 13 single-chain CPs of known carbon chain lengths. Two modified methods (method A and B), originating from the work of Sprengel et al., have been utilized on the same single-chain mixtures. All samples were analysed by H NMR and two-dimensional heteronuclear quantum coherence (HSQC) for this purpose. All three methods worked well for medium chlorinated (45-55% Cl) single-chain mixtures of known carbon chain lengths. Method A yielded the best result for mixtures of lower chlorine content (<45% Cl), method C gave better estimations for higher chlorine contents (>55% Cl). Compared to Mohr's titration, method A showed a deviation of 0.7-7.8% (3.6% average), method B 4.1-11.3% (7.0% average) and method C 0.6-11.6% (5.2% average), for all 13 single-chain mixtures. The new method C is the only method that could be applied for determining the chlorine percentage of industrial mixtures of multiple, unknown chain lengths.
Topics: Carbon; China; Chlorine; Environmental Monitoring; Hydrocarbons, Chlorinated; Magnetic Resonance Spectroscopy; Paraffin; Protons
PubMed: 36096309
DOI: 10.1016/j.chemosphere.2022.136312 -
Journal of Cutaneous Medicine and... 2019
Topics: Adult; Foreign-Body Reaction; Granuloma; Humans; Injections; Male; Paraffin; Penile Diseases
PubMed: 31070098
DOI: 10.1177/1203475419826971 -
Environmental Science & Technology Jul 2022In this work, a typical congener of short-chain chlorinated paraffins (SCCPs) with six chlorine atoms (CP-4, 1,2,5,6,9,10-CHCl, 250 ng/mL) was selected to elaborate the...
In this work, a typical congener of short-chain chlorinated paraffins (SCCPs) with six chlorine atoms (CP-4, 1,2,5,6,9,10-CHCl, 250 ng/mL) was selected to elaborate the comprehensive environmental transformation of SCCPs in rice seedling exposure system. CP-4 was quickly absorbed, translocated, and phytovolatilized by seedlings with a small quality of CP-4 (5.81-36.5 ng) being detected in the gas phase. Only 21.4 ± 1.6% of an initial amount (10,000 ng) of CP-4 remained in the exposure system at the end of exposure. Among the transformed CP-4, some were attributed to the degradation of the rhizosphere microorganism (9.1 ± 5.8%), root exudates (2.2 ± 4.2%), and abiotic transformation (3.0 ± 2.8%) that were proved by several transformation products found in the root exudate exposure groups and unplanted controls, and a majority was phytotransformed by rice seedlings. Here, 61 products were determined through complex transformation pathways, including multihydroxylation, -HCl elimination, dechlorination, acetylation, sulfation, glycosylation, and amide acid conjugation. The acetylated and amide acid conjugates of CPs were first observed. Phase I and Phase II phytometabolic reactions of CPs were found intertwining. These findings demonstrate that multiactive transformation reactions contribute to the overlook of CPs accumulated in plants and are helpful for the environmental and health risk assessments of SCCPs in agricultural plants.
Topics: Amides; China; Environmental Monitoring; Hydrocarbons, Chlorinated; Hydroponics; Oryza; Paraffin; Seedlings
PubMed: 35622943
DOI: 10.1021/acs.est.2c01119