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PubMed1989

Studies of nucleotide sequence homology between naphthalene-utilizing strains of bacteria.

The ability of P. putida, strain NCIB 9816, to grow with naphthalene (Nah+) and salicylate (Sal+) is correlated with the presence of an 83 kilobase (kb) conjugative plasmid (pDTG1). The genes encoding the upper pathway (Nah--greater than Sal) for naphthalene degradation are located on a 15 kb EcoRI fragment which was cloned into pKT230. The resulting recombinant, pDTG113, was nick-translated and used as a radioactive probe to investigate nucleotide sequence homology between the naphthalene-utilizing organisms, P. putida G7, P. putida NP, and strain PL6. Each of these bacterial strains were isolated from different locations at different times. The results show that all of these organisms contain closely related genes that are involved in naphthalene metabolism.

Enzymes↗
PubMed1980

Effect of decreased glucuronidation and sulfation on covalent binding of naphthalene in isolated rat hepatocytes.

Isolated hepatocytes metabolize naphthalene to water soluble compounds. During metabolism, reactive intermediates are formed which bind irreversibly to cellular macromolecules. When naphthalene concentrations in the incubation were raised from 400 to 1200 microM the formation of water soluble metabolites of the aromatic hydrocarbon increased about twice from 16 to 37 nmol/mg cellular protein X h, whereas covalent binding increased up to 10 times. This suggests a qualitative shift in the metabolic pattern of naphthalene probably due to the exhaustion of inactivating pathways. Inhibition of glucuronidation and sulfation -- 2 reactions involved in the metabolism of naphthalene -- did not change the amount of water soluble metabolites but dramatically increased binding.

Animals↗
PubMed1986

Naphthalene metabolism by human lung microsomal enzymes.

In the presence of glutathione and glutathione transferases, microsomal fractions prepared from fresh samples of human lung tissue obtained at resection metabolized naphthalene to naphthalene dihydrodiol and 3 glutathione conjugates at easily measurable rates. Addition of varying amounts of human lung microsomal protein markedly inhibited mouse liver microsome-catalyzed naphthalene metabolism in one sample but not the other. These data show that naphthalene is a good substrate for human pulmonary microsomal monooxygenases. In addition, these studies suggest that there may be an inhibitor, potentially released during tissue homogenization, that makes measurement of human lung xenobiotic metabolism difficult.

Cytochrome P-450 Enzyme System↗
PubMed2004

Sorption of naphthalene derivatives to soils from a long-term field experiment.

The influence of long-term farming practices on the soil's behaviour to adsorb hydrophobic organic compounds (HOCs) over long times was investigated. Adsorption of five naphthalene derivatives (naphthalene, 1-naphthol, 1-naphthylamine, 1-hydroxy-2-naphthoic acid, 1,4-naphthoquinone) was examined on soils with varying amounts and origins of soil organic matter obtained after amendment with different organic materials over more than 40 years. Soil organic matter, pore sizes and aggregate stability were significantly altered influencing the adsorption behaviour of the soils. Samples of soil amended with peat having an organic carbon content of 3.4% sorbed naphthalene derivatives stronger than the soil treated with sewage sludge (2.6% C(org)). All other treatments, calcium nitrate, plots without nitrogen fertilizers, grassland, animal manure, green manure and the fallowed soil sorbed less and no significant difference was found between them although the organic carbon content ranged from 1.0% to 2.6%. Thus, a decrease of the carbon content of a soil does not necessarily imply a reduction of sorption capacities for hydrophobic compounds such as naphthalene derivatives. Furthermore, the importance of protonation of HOCs for the adsorption on soil surfaces was shown. Different polarities of electronic structures of HOCs distinctly influence their adsorption behaviour.

Adsorption↗
PubMed2005

Determination of 1,2-dibromoethane, 1,4-dichlorobenzene and naphthalene residues in honey by gas chromatography--mass spectrometry using purge and trap thermal desorption extraction.

A highly sensitive method for the determination of 1,2-dibromoethane, 1,2-dichlorobenzene and naphthalene residues in honey was developed, using gas chromatography-mass spectrometry combined with a purge and trap thermal desorption system as the extraction technique. Optimal conditions for isolation and separation were established and calibration curves were constructed. Linearity was held between 2.4 and 300 microg kg(-1) honey for 1,2-dibromoethane, 0.5 and 300 microg kg(-1) for 1,4-dichlorobenzene and 0.125 and 3000 microg kg(-1) for naphthalene. The detection limits were found to be 0.8, 0.15 and 0.05 microg kg(-1) honey for 1,2-dibromoethane, 1,4-dichlorobenzene and naphthalene, respectively. The method was applied to the analysis of 25 Greek honey samples. 1,2-Dibromoethane was not found in the majority of the samples, while only one sample was found to contain both 1,4-dichlorobenzene and naphthalene residues at concentrations exceeding 10 microg kg(-1).

Chlorobenzenes↗
PubMed2006

Naphthalene treatment alters liver intermediary metabolism and levels of steroid hormones in plasma of rainbow trout (Oncorhynchus mykiss).

To assess the effects of naphthalene on liver intermediary metabolism and plasma steroid hormones, immature female rainbow trout (Oncorhynchus mykiss), in a first experiment, were intraperitoneally injected (2 microLg(-1)) with vegetable oil alone (control) or containing naphthalene (10 and 50 mgkg(-1)) and returned to their tanks. At 1, 3, and 6h after injection, eight fish were sampled from each group. A second experiment was similarly designed but used fish intraperitoneally implanted (10 microLg(-1)) with slow-release coconut oil implants alone (control) or containing naphthalene at doses of 10 and 50 mgkg(-1) body weight that were sampled 1, 3, and 5 days after injection. At each sampling time, plasma hormone levels (cortisol and 17beta-estradiol) and metabolic parameters in plasma (glucose and lactate) and liver (glucose, lactate, and glycogen levels and HK, GK, GPase, GDH, FBPase, and PK activities) were assessed. Changes described for both hormonal systems resulted in a decrease in plasma levels of cortisol and 17beta-estradiol. Changes observed in intermediary metabolism described effects in several pathways of liver energy metabolism due to naphthalene. These changes can be summarized as increased glycogenolysis, use of exogenous glucose, and glycolysis and decreased gluconeogenesis. The increased energy production in liver suggested by these changes can be related to the increased detoxification activity known to occur in liver after PAH exposure, and can be also related directly or indirectly to the changes observed in the levels of plasma steroids.

Animals↗
PubMed2004

Adsorption of naphthalene on zeolite from aqueous solution.

Polynuclear aromatic hydrocarbons (PAHs), which are environmental hormones and carcinogens, are viewed as the priority pollutants to deal with by many countries. Most PAHs are hydrophobic with high boiling and melting points and high electrochemical stability, but with low water solubility. Compared with other PAH species, naphthalene has less toxicity and is easily found in the environment. Thus, naphthalene is usually adopted as a model compound to examine the environmental and health aspects of PAHs. This study attempted to use an adsorption process to remove naphthalene from a water environment. The adsorption equilibrium of naphthalene on zeolite from water-butanol solution, which is a surfactant-enriched scrubbing liquid, was successfully evaluated by Langmuir, Freundlich, and linear isotherms. Among the tested kinetics models in this study (e.g., pseudo-first-order, pseudo-second-order, and Elovich rate equations), the pseudo-second-order equation successfully predicted the adsorption.

Adsorption↗
PubMed2004

The role of interfacial films in the mass transfer of naphthalene from creosotes to water.

Viscous, semi-rigid interfacial films that are formed at the interface of certain multi-component non-aqueous phase liquid (NAPLs) and water can significantly reduce the rates of mass transfer of solutes. Creosote-water systems were investigated for their ability to form interfacial films. The effects of these films on the creosote-water partition and on mass transfer of a representative solute, naphthalene, were investigated in a series of experiments. The area-independent mass transfer coefficient of naphthalene contained in creosote decreased by 30% over a 1-week period in systems containing creosote and water. Further aging for up to 21 days did not result in significant additional decreases in the mass transfer coefficient. The creosote-water partition coefficient, however, did not change with extended contact. The presence of viscous interfacial films in creosote-water systems was demonstrated in pendant drop tests. These interfacial films most likely caused the reduction in solute mass transfer coefficients by providing significant resistance to the diffusion of solutes through the interfacial film. Results from mass transfer experiments conducted under different system conditions suggested that hindered diffusion of naphthalene through the bulk creosote phase, changes in composition of creosote as a result of extended dissolution, or changes in creosote-water interfacial area did not contribute to the decrease in naphthalene mass transfer coefficient.

Computer Simulation↗
PubMed2003

Effect of additional carbon source on naphthalene biodegradation by Pseudomonas putida G7.

Addition of a carbon source as a nutrient into soil is believed to enhance in situ bioremediation by stimulating the growth of microorganisms that are indigenous to the subsurface and are capable of degrading contaminants. However, it may inhibit the biodegradation of organic contaminants and result in diauxic growth. The objective of this work is to study the effect of pyruvate as another carbon source on the biodegradation of polynuclear aromatic hydrocarbons (PAHs). In this study, naphthalene was used as a model PAH, ammonium sulfate as a nitrogen source, and oxygen as an electron acceptor. Pseudomonas putida G7 was used as a model naphthalene-degrading microorganism. From a chemostat culture, the growth kinetics of P. putida G7 on pyruvate was determined. At concentrations of naphthalene and pyruvate giving similar growth rates of P. putida G7, diauxic growth of P. putida G7 was not observed. It is suggested that pyruvate does not inhibit naphthalene biodegradation and can be used as an additional carbon source to stimulate the growth of P. putida G7 that can degrade polynuclear aromatic hydrocarbons.

Biodegradation, Environmental↗
PubMed2004

Enhanced solubilization and removal of naphthalene and phenanthrene by cyclodextrins from two contaminated soils.

The development of innovative methods for cleaning contaminated soils has emerged as a significant environmental priority. Herein, are investigated the effectiveness of cyclodextrin (CD) to solubilize and to extract organic pollutants from soils. The interactions in the cyclodextrin/pollutant/soil system have been studied "step by step" using two kinds of polycyclic aromatic hydrocarbons (PAH), naphthalene (Nap) and phenanthrene (Phe), cyclodextrins and soils. Inclusion complex formation of PAH with beta-cyclodextrin (beta-CD) and hydroxypropyl-beta-cyclodextrin (HPCD) has been investigated and was proposed as a way to facilitate the pollutant removal from soil. Little effect of ionic strength was observed on CD complex formation for both compounds. The solubility of PAH in 50 g L(-1) of HPCD was enhanced 20- and 90-fold for naphthalene and phenanthrene, respectively. Batch experiments were performed to study the adsorption-desorption of two PAH on two soils and the influence of CDs over these processes. These experiments were also conducted with a mixture of two PAH. The batch desorption results indicate that removal capacity of HPCD was higher than that of beta-CD. Phenanthrene was strongly sorbed on soils, this led to low desorption rates compared to that of naphthalene, whatever the extracting agent used. When HPCD solution was used as a flushing agent, 80% of naphthalene and 64% of phenanthrene recovery from soil were observed. For both compounds, the slowest desorption rate was found for the soil that had the greatest content of organic matter. CD sorption on soils, was relatively low and depended on soil type. The soil organic matter (SOM) could favor the retention of both CD and pollutant involving the extraction rate to be decreased. A competitive hydrophobic interactions of pollutant between SOM and CD molecules, and co-sorption were expected to be the mechanism for the inhibited desorption.

Adsorption↗
PubMed2004

Steric-controlled excimer formation in naphthalene analogues of chalcone.

Naphthalene analogues of chalcone (typical vinylarenes) are well known for their intramolecular charge transfer (CT) process. The all four possible isomers NC1, NC2, NC3 and NC4 were observed to give structure-less broad CT bands, whereas, excimer formation at higher concentration was reported only for NC4 [Res. Chem. Intermed. 25 (1999) 903]. However, conventional GMMX calculation data reveals that the naphthalene portion of all the isomers are planar, hence, excimer emission is expected from all of them, i.e., if NC4 can form an excimer, then the rests are also capable of doing it. In this paper we have actually succeeded in resolving the excimer peaks for all these four isomers by optimization of concentration, though the extent of excimer formation was observed to be the maximum for NC4. These differential tendencies of excimer formation can be explained by the change in extent of intermolecular stacking interaction of the naphthalene moieties. Variation occurs here due to steric perturbation arising from the specific orientation of the near resident non-planar aroyl component with respect to the naphthalene moiety.

Chalcone↗
PubMed2006

Removal of naphthalene from aqueous solution on chemically modified activated carbons.

The aim of this work was to correlate the textural and chemical features of carbonaceous adsorbents with the adsorption capacity of naphthalene from aqueous phase, at the concentration in which this compound is usually found in wastewater from coke ovens. The study reveals that the adsorption capacity in different carbon materials depends not only on the textural characteristics of the material but also on the functionalities of the activated carbons. The micropores of the adsorbents, particularly those of narrower diameter, were found to be active sites for the retention of naphthalene. In contrast, the modification of the surface chemistry of the carbon materials led to a decrease in the adsorption capacities. Dispersive forces play an important role, and adsorbents with a higher non-polar character have proven to be more efficient for the naphthalene adsorption. This behaviour has been linked to the presence of specific interactions between the basal planes and the polyaromatic structure of the naphthalene molecule.

Adsorption↗
PubMed2000

Alteration of pulmonary neuroendocrine cells during epithelial repair of naphthalene-induced airway injury.

Whole-mount airway preparations isolated from the lungs of mice treated by intraperitoneal injection of naphthalene and allowed to recover for 5 days were examined for the distribution and abundance of solitary pulmonary neuroendocrine cells (PNECs) and neuroepithelial bodies (NEBs) along the main axial pathway of the right middle lobe. Sham mice treated with corn oil vehicle were examined in a similar manner. An antibody to calcitonin gene-related peptide, a neuroendocrine cell marker, was used to identify the location, size, and number of PNECs and NEBs in the airways. After naphthalene treatment and epithelial repair, NEBs were significantly increased along the walls of the airways as well as on branch point ridges. The surface area covered by NEBs composed of 20 or fewer PNECs was significantly enlarged after naphthalene treatment compared with control NEBs of an equivalent cell number. The PNEC number per square millimeter was also increased more than threefold above control values after naphthalene treatment. These findings provide further support for a key role of neuroendocrine cells in the reparative process of airway epithelial cell renewal after injury.

Animals↗
PubMed2000

Use of substrate responsive-direct viable counts to visualize naphthalene degrading bacteria in a coal tar-contaminated groundwater microbial community.

A microscopy-based method was developed to distinguish naphthalene-degrading bacteria within the microbial community of a coal tar-contaminated groundwater system. Pure cultures of Pseudomonas putida NCIB 9816-4 were used to develop the substrate responsive-direct viable count (SR-DVC) method. Cells were concentrated on membrane filters, placed on agar plates of Stanier's minimal basal salts media containing antibiotics (nalidixic acid, piromidic acid, pipemidic acid, and cephalexin), and exposed to vapors of naphthalene. Following brief incubation, samples were fixed in 2% formaldehyde and examined by epifluorescent microscopy. Pure cultures displayed the expected cell elongation response to the SR-DVC assay and required a minimum incubation time of 9 h for differentiation of elongated cells. When applied to groundwater samples from the study site, naphthalene responsive cells in the groundwater community were easily distinguished from unresponsive cells and debris (350+/-180 substrate responsive cells/ml, relative to negative controls with no added growth substrate). In an attempt to reduce background counts of elongated bacteria and fungi, the SR-DVC procedure was modified by adding a wash step prior to incubation and a fungal inhibitor, cyclohexamide, to the plates. When groundwater samples were subjected to the modified procedure, only cells in washed samples showed a significant response to naphthalene (150+/-25 cells/ml), indicating the presence of inhibitory substances in the groundwater. Variations in response of the groundwater microbial community to the two SR-DVC procedures suggest that subsurface conditions (microbial and chemical composition) vary temporally. SR-DVC allows the phenotypes of individual naturally occurring cells to be assessed.

Bacteria↗
PubMed1985

Mothball differentiation: naphthalene from paradichlorobenzene.

In order to develop a rapid, simple test to differentiate toxic naphthalene from the less toxic mothball ingredient paradichlorobenzene, both types of mothballs were dissolved in isopropyl alcohol, ethanol, methanol, and turpentine. Twenty-five naphthalene and 25 paradichlorobenzene mothballs were weighed, randomly grouped, and then dissolved in the solvents. After 30 minutes, the mothballs were reweighed. Isopropyl alcohol, ethanol, and methanol did not differentially dissolve the mothballs fast enough to provide a useful test. Turpentine, however, dissolved paradichlorobenzene at a much more rapid rate than naphthalene (P less than .001). After 60 minutes, all of the paradichlorobenzene mothballs had dissolved, while at least 25% of the naphthalene remained. Thus, when confronted with an ingestion of unlabeled mothballs, the physician could gain preliminary information regarding possible toxicity by dissolving a remaining mothball in turpentine for 60 minutes.

Chlorobenzenes↗
PubMed1999

Genetic characterization and evolutionary implications of a chromosomally encoded naphthalene-degradation upper pathway from Pseudomonas stutzeri AN10.

Pseudomonas stutzeri strain AN10 is a naphthalene-degrading strain whose dissimilatory genes are chromosomally encoded. We sequenced a total of 11514bp including the entire naphthalene-degradation upper pathway (nah) of P. stutzeri AN10. Nine open reading frames, nahAaAbAcAdBFCED, encoding the enzymes for the degradation of naphthalene to salicylate, were identified. The nah genes of P. stutzeri AN10 have been compared with genes encoding isofunctional proteins from other Pseudomonas naphthalene-degradation upper pathways. The implications of the sequence homologies to the evolution of aromatic catabolic pathways are discussed. Our findings indicate that this entire catabolic module of P. stutzeri AN10 was recruited from other microorganisms and a short period of time has elapsed after its incorporation within the P. stutzeri AN10 genome. Comparisons also suggest the coexistence of two entire nah upper pathways in a host strain, and further recombination between them. These events could accelerate the evolution of modern catabolic pathways.

Amino Acid Sequence↗
PubMed1975

Initial reactions in the oxidation of naphthalene by Pseudomonas putida.

A strain of Pseudomonas putida that can utilize naphthalene as its sole source of carbon and energy was isolated from soil. A mutant strain of this organism, P. putida 119, when grown on glucose in the presence of naphthalene, accumulates optically pure (+)-cis-1(R),2(S)-dihydroxy-1,2-dihydronaphthalene in the culture medium. The cis relative stereochemistry in this molecule was established by nuclear magnetic resonance spectrometry. Radiochemical trapping experiments established that this cis dihydrodiol is an intermediate in the metabolism of naphthalene by P. Fluorescens (formerly ATCC, 17483), P. putida (ATCC, 17484), and a Pseudomonas species (NCIB 9816), as well as the parent strain of P. putida described in this report. Formation of the cis dihydrodiol is catalyzed by a dioxygenase which requires either NADH or NADPH as an electron donor. A double label procedure is described for determining the origin of oxygen in the cis dihydrodiol under conditions where this metabolite would not normally accumulate. Several aromatic hydrocarbons are oxidized by cell extracts prepared from naphthalene-grown cells of P. putida. The cis dihydrodiol is converted to 1,2-dihydroxynaphthalene by an NAD+-dependent dehydrogenase. This enzyme is specific for the (+) isomer of the dihydrodiol and shows a primary isotope effect when the dihydrodiol is substituted at C-2 with deuterium.

Culture Media↗
PubMed2002

Leaching and primary biodegradation of sulfonated naphthalenes and their formaldehyde condensates from concrete superplasticizers in groundwater affected by tunnel construction.

Sulfonated naphthalenes and their formaldehyde condensates (SNFC) are used as concrete superplasticizers fortunnel construction through aquifers.This paperdiscusses their primary biodegradation in groundwater affected by construction activities. The analyses of groundwater samples collected 5 m away from a construction site clearly indicated that components of the applied SNFC product leached into the groundwater. A maximum total concentration of these compounds of 233 microg/L was found, and it was shown that only the monomeric sulfonated naphthalenes andthe condensates uptothetetramerleached in substantial amounts. The decrease in concentration of several monomeric components could not be explained by mere dispersion but rather indicates a biological transformation in the aquifer. This was confirmed at a second field site and by laboratory degradation experiments with piezometer material as inoculum. Lag phases for the individually degradable sulfonated naphthalenes ranged from 0 to 96 d. Naphthalene-1,5-disulfonate and the oligomeric components were neither degraded in the aquifer nor in the laboratory experiments within an observation time of up to 195 d. This clearly indicates their persistence in subsurface waters.

Disinfectants↗