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1.
Molecules ; 22(5)2017 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-28509873

RESUMO

Several constituents of essential oils have been shown to be active against pathogens such as bacteria, fungi, and protozoa. This study demonstrated the in vitro action of ten compounds present in essential oils against Leishmania amazonensis promastigotes. With the exception of p-cymene, all evaluated compounds presented leishmanicidal activity, exhibiting IC50 between 25.4 and 568.1 µg mL-1. Compounds with the best leishmanicidal activity presented a phenolic moiety (IC50 between 25.4 and 82.9 µg mL-1). Alicyclic alcohols ((-)-menthol and isoborneol) and ketones ((-)-carvone) promoted similar activity against the parasite (IC50 between 190.2 and 198.9 µg mL-1). Most of the compounds showed low cytotoxicity in L929 fibroblasts. Analysis of the structure-activity relationship of these compounds showed the importance of the phenolic structure for the biological action against the promastigote forms of the parasite.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Antiprotozoários/química , Canfanos/química , Canfanos/farmacologia , Hidrocarbonetos Alicíclicos/química , Hidrocarbonetos Alicíclicos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Relação Estrutura-Atividade
2.
Mar Pollut Bull ; 115(1-2): 383-390, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28010882

RESUMO

In this study, the concentration and sources of aliphatic and petroleum markers were investigated in 105 samples of Anzali, Rezvanshahr and Astara cores from the southwest of Caspian Sea. Petroleum importation was diagnosed as a main source in most depths of cores by the results of unresolved complex mixture, carbon preference index and hopanes and steranes. From the chemical diagnostic parameters, petroleum inputs in sediment of cores were determined to be different during years and the sources of hydrocarbons in some sections differed than Anzali and Turkmenistan and Azerbaijan oils. Diagenic ratios in most sediments of upper and middle sections in Astara core were determined to be highly similar to those of Azerbaijan oil, while the presence of Turkmenistan and Anzali oils were detected in a few sections of Anzali and Rezvanshahr cores and only five layers of downer section in Anzali core, respectively.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos/análise , Poluição por Petróleo/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Hidrocarbonetos Alicíclicos/análise , Oceanos e Mares , Petróleo
3.
Curr Med Chem ; 23(23): 2507-54, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27121188

RESUMO

The progesterone receptor (PR) is a ligand-activated steroid receptor in the nuclear receptor (NR) superfamily of transcription factor. Besides gynecological and obstetrical indications, the involvement/mechanism of PR in many other diseases, such as oncology, neurology, immunology, etc. has been revealed and studied in recent decades. Therapeutic agents that selectively activate or inhibit PR have been developed. PR agonists have generally been used in oral contraception and postmenopausal hormone replacement therapy (HRT), typically in combination with estrogens. PR antagonists and selective PR modulators (SPRMs) can be useful therapies for hormone dependent breast and prostate cancers, nonmalignant chronic conditions such as fibroids, and endometriosis. This review provides an overview and detailed discussions about the recent development of chemical structures of the PR ligands, their structural characteristics (particularly those contributing to their activity and selectivity), in vitro/in vivo studies and clinical trial outcomes, and the synthetic methodologies.


Assuntos
Ligantes , Receptores de Progesterona/metabolismo , Boranos/síntese química , Boranos/química , Boranos/metabolismo , Cumarínicos/síntese química , Cumarínicos/química , Cumarínicos/metabolismo , Compostos Heterocíclicos de Anéis Fundidos/síntese química , Compostos Heterocíclicos de Anéis Fundidos/química , Compostos Heterocíclicos de Anéis Fundidos/metabolismo , Terapia de Reposição Hormonal , Humanos , Hidrocarbonetos Alicíclicos/síntese química , Hidrocarbonetos Alicíclicos/química , Hidrocarbonetos Alicíclicos/metabolismo , Indóis/síntese química , Indóis/química , Indóis/metabolismo , Ligação Proteica , Receptores de Progesterona/agonistas , Receptores de Progesterona/antagonistas & inibidores , Esteroides/síntese química , Esteroides/química , Esteroides/metabolismo , Vitamina D/análogos & derivados , Vitamina D/síntese química , Vitamina D/metabolismo
4.
Chem Rev ; 116(5): 2937-81, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26854865

RESUMO

This review covers the addition of diazo compounds to ketones to afford homologated ketones, either in the presence or in the absence of promoters or catalysts. Reactions with diazoalkanes, aryldiazomethanes, trimethylsilyldiazomethane, α-diazo esters, and disubstituted diazo compounds are covered, commenting on the complex regiochemistry of the reaction and the nature of the catalysts and promoters. The recent reports on the enantioselective version of ketone homologation reactions are gathered in one section, followed by reports on the use of cyclic ketones ring expansion in total synthesis. Although the first reports of this reaction appeared in the literature almost one century ago, the recent achievements, in particular, for the asymmetric version, forecast the development of new breakthroughs in the synthetically valuable field of diazo chemistry.


Assuntos
Compostos de Diazônio/química , Cetonas/química , Técnicas de Química Sintética , Compostos Heterocíclicos/síntese química , Hidrocarbonetos Alicíclicos/síntese química
5.
Arch Pharm (Weinheim) ; 349(4): 252-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26892182

RESUMO

Preclinical studies for neurodegenerative diseases have shown a multi-targeted approach to be successful in the treatment of these complex disorders with several pathoetiological pathways. Polycyclic compounds, such as NGP1-01 (7a), have demonstrated the ability to target multiple mechanisms of the complex etiology and are referred to as multifunctional compounds. These compounds have served as scaffolds with the ability to attenuate Ca(2+) overload and excitotoxicity through several pathways. In this study, our focus was on mitigating Ca(2+) overload through the L-type calcium channels (LTCC). Here, we report the synthesis and biological evaluation of several novel polycyclic compounds. We determined the IC50 values for both the pentacycloundecylamines and the triquinylamines by means of a high-throughput fluorescence calcium flux assay utilizing Fura-2/AM. The potential of these compounds to offer protection against hydrogen peroxide-induced cell death was also evaluated. Overall, 8-benzylamino-8,11-oxapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (NGP1-01, 7a) had the most favorable pharmacological profile with an IC50 value of 86 µM for LTCC inhibition and significant reduction of hydrogen peroxide-induced cell death. In general, the triquinylamines were more active as LTCC blockers than the oxa-pentacycloundecylamines. The aza-pentacycloundecylamines were potent LTCC inhibitors, with 8-hydroxy-N-phenylethyl-8,11-azapentacyclo[5.4.0.0(2,6) .0(3,10) .0(5,9) ]undecane (8b) also able to offer significant protection in the cell viability assays.


Assuntos
Aminas/química , Bloqueadores dos Canais de Cálcio/química , Canais de Cálcio Tipo L/metabolismo , Cálcio/metabolismo , Hidrocarbonetos Alicíclicos/química , Quinonas/química , Aminas/síntese química , Aminas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/síntese química , Bloqueadores dos Canais de Cálcio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Hidrocarbonetos Alicíclicos/síntese química , Hidrocarbonetos Alicíclicos/farmacologia , Peróxido de Hidrogênio/farmacologia , L-Lactato Desidrogenase/metabolismo , Células PC12 , Quinonas/síntese química , Quinonas/farmacologia , Ratos , Relação Estrutura-Atividade
6.
Plant Physiol ; 170(2): 921-34, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26644508

RESUMO

Plant cuticular waxes play a crucial role in limiting nonstomatal water loss. The goal of this study was to localize the transpiration barrier within the layered structure of cuticles of eight selected plant species and to put its physiological function into context with the chemical composition of the intracuticular and epicuticular wax layers. Four plant species (Tetrastigma voinierianum, Oreopanax guatemalensis, Monstera deliciosa, and Schefflera elegantissima) contained only very-long-chain fatty acid (VLCFA) derivatives such as alcohols, alkyl esters, aldehydes, and alkanes in their waxes. Even though the epicuticular and intracuticular waxes of these species had very similar compositions, only the intracuticular wax was important for the transpiration barrier. In contrast, four other species (Citrus aurantium, Euonymus japonica, Clusia flava, and Garcinia spicata) had waxes containing VLCFA derivatives, together with high percentages of alicyclic compounds (triterpenoids, steroids, or tocopherols) largely restricted to the intracuticular wax layer. In these species, both the epicuticular and intracuticular waxes contributed equally to the cuticular transpiration barrier. We conclude that the cuticular transpiration barrier is primarily formed by the intracuticular wax but that the epicuticular wax layer may also contribute to it, depending on species-specific cuticle composition. The barrier is associated mainly with VLCFA derivatives and less (if at all) with alicyclic wax constituents. The sealing properties of the epicuticular and intracuticular layers were not correlated with other characteristics, such as the absolute wax amounts and thicknesses of these layers.


Assuntos
Ácidos Graxos/metabolismo , Hidrocarbonetos Alicíclicos/metabolismo , Epiderme Vegetal/fisiologia , Transpiração Vegetal/fisiologia , Água/metabolismo , Ceras/metabolismo , Transporte Biológico , Cromatografia Gasosa , Epiderme Vegetal/ultraestrutura , Polímeros/metabolismo , Especificidade da Espécie
7.
Magn Reson Chem ; 53(9): 754-68, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26275226

RESUMO

High-field NMR spectra of Murchison meteorite methanolic extracts revealed primarily aliphatic extraterrestrial organic matter (EOM) with near statistical branching of commonly C(3-5) units separated by heteroatoms and aromatic units. The ratios of CCH, OCH and C(sp2)H units were 89 : 8 : 3, whereas carbon-based aliphatic chain termination was in the order methyl > -COOH > -CH(CH3)COOH. Aliphatic methine carbon was abundant, but its weak NMR signatures were primarily deduced from JRES (J-resolved) NMR spectra. Carbon NMR spectra were dominated by methylene and methyl carbon; strong apodization revealed methine carbon, of which about 20% was aromatic. Extrapolation provided 5-7% aromatic carbon present in Murchison soluble EOM. Compositional heterogeneity in Murchison methanolic extracts was visible in NMR and Fourier transform ion cyclotron (FTICR) mass spectra obtained from a few cubic millimeters of solid Murchison meteorite; increasing sample size enhanced uniformity of NMR spectra. Intrinsic chemical diversity and pH-dependent chemical shift variance contributed to the disparity of NMR spectra. FTICR mass spectra provided distinct clustering of CHO/CHOS and CHNO/CHNOS molecular series and confirmed the prevalence of aliphatic/alicyclic (73%) over single aromatic (21%) and polyaromatic (6%) molecular compositions, suggesting extensive aliphatic substitution of aromatic units as proposed by NMR. Murchison soluble EOM molecules feature a center with enhanced aromatic and heteroatom content, which provides rather diffuse and weak NMR signatures resulting from a huge overall chemical diversity. The periphery of Murchison EOM molecules comprises flexible branched aliphatic chains and aliphatic carboxylic acids. These project on narrow ranges of chemical shift, facilitating observation in one-dimensional and two-dimensional NMR spectra. The conformational entropy provided by these flexible surface moieties facilitates the solubility of EOM.


Assuntos
Carbono/análise , Ácidos Carboxílicos/isolamento & purificação , Meio Ambiente Extraterreno/química , Hidrocarbonetos Alicíclicos/isolamento & purificação , Hidrocarbonetos Aromáticos/isolamento & purificação , Meteoroides , Ciclotrons , Entropia , Análise de Fourier , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Metanol/química , Solventes/química
8.
Macromol Rapid Commun ; 36(8): 733-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25721263

RESUMO

Propylene polymerization is carried out with a C 2 -symmetric metallocene catalyst of rac-Et(Ind)2 ZrCl2 /MAO at 40 °C in the presence of a cyclo-triene of trans,trans,cis-1,5,9-cyclododecatriene ((E,E,Z)-CDT). Comonomer incorporations are rather low (<0.10 mol%). However, it is shown for the first time that the comonomer causes a noticeable increase in poly-propylene -isotacticity (>7% in [mmmm]). (E,E,Z)-CDT is speculated to coordinate to the metal center forming comonomer-complexed active sites in charge of the entire polymerization reaction with decreased activity however increased propylene -enantiomorphic selectivity.


Assuntos
Compostos Organometálicos/química , Polimerização , Polipropilenos/síntese química , Alcenos/síntese química , Alcenos/química , Catálise , Hidrocarbonetos Alicíclicos/química , Estrutura Molecular , Compostos Organometálicos/síntese química , Polipropilenos/química , Estereoisomerismo , Zircônio/química
9.
Talanta ; 131: 315-24, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25281108

RESUMO

This work proposes an analytical procedure for measuring aliphatic and aromatic hydrocarbons fractions present in groundwater. In this method, hydrocarbons are solid phase extracted (SPE) twice from the groundwater and the resulting fractions are analyzed by gas chromatography with flame ionization detection. The first SPE disposes the hydrocarbons present in groundwater in organic solvents and the second SPE divides them into aliphatic and aromatic hydrocarbons. The validation study is carried out and its uncertainties are discussed. Identifying the main sources of uncertainty is evaluated through applying the bottom-up approach. Limits of detection for hydrocarbons ranges are below 5 µg L(-1), precision is not above of 30%, and acceptable recoveries are reached for aliphatic and aromatic fractions studied. The uncertainty due to volume of the sample, factor of calibration and recovery are the highest contributions. The expanded uncertainty range from 13% to 26% for the aliphatic hydrocarbons ranges and from 14% to 23% for the aromatic hydrocarbons ranges. As application, the proposed method is satisfactorily applied to a set of groundwater samples collected in a polluted area where there is evidence to present a high degree of hydrocarbons. The results have shown the range of aliphatic hydrocarbons >C21-C35 is the most abundant, with values ranging from 215 µg L(-1) to 354 µg L(-1), which it is associated to a contamination due to diesel.


Assuntos
Cromatografia Gasosa/métodos , Água Subterrânea/análise , Hidrocarbonetos Alicíclicos/análise , Hidrocarbonetos Aromáticos/análise , Petróleo/análise , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Ionização de Chama/métodos
10.
Chem Biodivers ; 11(10): 1567-96, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25329785

RESUMO

This review, including some new experimental results, is the summary of a talk at the 'flavors & fragrances 2013' conference in Leipzig, organized jointly by the GDCh, the Liebig-Vereinigung, and the EuCheMS. After times of searching for natural odor principles and serendipitous discoveries by chemical inspiration, directed odorant design today offers the highest hit rates for the discovery of new odorants, although serendipity still plays a role. Keeping intact the electronic shape required for a certain olfactophore-binding geometry, one can add or subtract structural elements, rigidify molecular structures, or introduce more structural flexibility. To find out which structural features are critical, the 'seco-approach', in which different fragments are removed by cutting strategic bonds, is the most analytical. Following this approach, such ingredients as Serenolide, Sylkolide, and Pomarose were designed. Transferring this design principle from the family of damascones to that of the theaspiranes led to the discovery of Cassyrane, though completely different structural features turned out to be relevant. Application of the seco-concept to a 3,7a-substituted 2,6,7,7a-tetrahydro-1H-inden-5-yl musk lead structure derived from carotol resulted in the discovery of a new family of dienone musks with novel structure-odor correlations. However, cutting the C(2)-O bond of Cassyrane and oxidizing the resulting seco-structure to the 1,2,5,1″-tetradehydro derivative links the family of dienone musks with that of blackcurrant odorants, but the resulting target structures turned out to be potent orris odorants. (3E,5E)-5-(tert-Butyl)octadeca-3,5-dien-2-one even possesses the lowest odor threshold in the whole ionone family (0.036 ng/l air), which could be rationalized by a superposition analysis on (-)-cis-γ-irone. In the course of the synthesis of these high-impact orris odorants, we discovered that, depending on the reaction conditions, the dehydration step of the intermediate 5-hydroxyalk-3-yn-2-ones was accompanied by a carbenium-ion rearrangement. Depending on the substitution pattern, these rearrangement products and their derivatives possessed interesting musky-woody olfactory properties reminiscent of Cashmeran, demonstrating that the same structural elements can code for completely different odors, i.e., cassis, musk, orris, violet, and Cashmeran-type, depending only on their spatial arrangement.


Assuntos
Furanos/química , Hidrocarbonetos Alicíclicos/química , Indanos/química , Odorantes/análise , Estrutura Molecular
11.
J Org Chem ; 79(21): 10013-29, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25260123

RESUMO

The synthesis of donor- (D) and/or acceptor (A)-expanded [4]radialenes has been developed on the basis of readily available dibromoolefin (7), tetraethynylethene (10 and 20), and vinyl triflate (12) building blocks. The successful formation of D/A radialenes relies especially on (1) effective use of a series alkynyl protecting groups, (2) Sonogashira cross-coupling reactions, and (3) the development of ring closing reactions to form the desired macrocyclic products. The expanded [4]radialene products have been investigated by spectroscopic (UV-vis absorption and emission) and quantum chemical computational methods (density functional theory and time dependent DFT). The combined use of theory and experiment provides a basis to evaluate the extent of D/A interactions via the cross-conjugated radialene framework as well as an interpretation of the origin of D/A interactions at an orbital level.


Assuntos
Alquinos/química , Hidrocarbonetos Alicíclicos/química , Hidrocarbonetos Alicíclicos/síntese química , Hidrocarbonetos Bromados/química , Compostos Macrocíclicos/síntese química , Compostos Macrocíclicos/química , Estrutura Molecular , Teoria Quântica , Espectrofotometria Ultravioleta
12.
ACS Comb Sci ; 16(3): 146-53, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24479637

RESUMO

One-pot variation of Castagnoli condensation, that is, reaction of cyclic anhydrides, amines, and aldehydes, has been developed as a combinatorial approach to 1,2-disubstituted 5-oxopyrrolidine- and 6-oxopiperidine-3-carboxylic acids, as well as their benzo-analogues. Utility of the method to multigram preparation of building blocks and synthetic intermediates was also demonstrated. The final products are obtained in high yields and diastereoselectivity. The method fits well in the concept of lead-oriented synthesis; in particular, it can be used for the design of lead-like compound libraries, even if the strictest cut-offs are applied to the physicochemical properties of their members.


Assuntos
Anidridos/síntese química , Técnicas de Química Combinatória , Hidrocarbonetos Alicíclicos/síntese química , Aldeídos/química , Aminas/química , Anidridos/química , Hidrocarbonetos Alicíclicos/química , Estrutura Molecular , Estereoisomerismo
13.
PLoS One ; 8(6): e66971, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23825601

RESUMO

The genomes of the Betaproteobacteria Alicycliphilus denitrificans strains BC and K601(T) have been sequenced to get insight into the physiology of the two strains. Strain BC degrades benzene with chlorate as electron acceptor. The cyclohexanol-degrading denitrifying strain K601(T) is not able to use chlorate as electron acceptor, while strain BC cannot degrade cyclohexanol. The 16S rRNA sequences of strains BC and K601(T) are identical and the fatty acid methyl ester patterns of the strains are similar. Basic Local Alignment Search Tool (BLAST) analysis of predicted open reading frames of both strains showed most hits with Acidovorax sp. JS42, a bacterium that degrades nitro-aromatics. The genomes include strain-specific plasmids (pAlide201 in strain K601(T) and pAlide01 and pAlide02 in strain BC). Key genes of chlorate reduction in strain BC were located on a 120 kb megaplasmid (pAlide01), which was absent in strain K601(T). Genes involved in cyclohexanol degradation were only found in strain K601(T). Benzene and toluene are degraded via oxygenase-mediated pathways in both strains. Genes involved in the meta-cleavage pathway of catechol are present in the genomes of both strains. Strain BC also contains all genes of the ortho-cleavage pathway. The large number of mono- and dioxygenase genes in the genomes suggests that the two strains have a broader substrate range than known thus far.


Assuntos
Comamonadaceae/genética , Comamonadaceae/fisiologia , Genômica , Sequência de Bases , Cloratos/metabolismo , Comamonadaceae/metabolismo , Genoma Bacteriano/genética , Hidrocarbonetos Alicíclicos/metabolismo , Nitratos/metabolismo , Oxigênio/metabolismo , Especificidade da Espécie
14.
Org Biomol Chem ; 11(8): 1306-17, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23188211

RESUMO

Bullvalene is an organic molecule that spontaneously undergoes Cope rearrangements, resulting in a reconfiguration of its carbon framework. During our study of oligosubstituted bullvalenes, which are structurally dynamic shapeshifting molecules, we found that we could isolate one metastable isomer from the interconverting population of 1680 constitutional isomers (852 structures if enantiomeric pairs are counted once). The preferential formation and unexpected stability of this isomer led to many questions, which we have addressed in this report. (1) What is its structure? (2) How many rearrangements are required to form this isomer from the initial bullvalene structure? (3) Why is it the preferred isomer? (4) What is the role of the substituents in its energetic preference? Our answers required synthesis, HPLC isolation, NMR characterizations, network construction and analysis, and computational (DFT) studies. The results of these efforts revealed the remarkable interconversion network of bullvalene rearrangements. The formation of this metastable isomer is preferred by both thermodynamic and kinetic factors and the ester substituent amplifies the energy difference between various structural isomers of oligosubstituted bullvalenes. The shapeshifting nature of oligosubstituted bullvalene is a useful and unusual property that has many potential applications. Insights into their rearrangements, energy landscape and substituent effect will be important knowledge for the development of these molecules towards materials, sensors and biologically active compounds.


Assuntos
Hidrocarbonetos Alicíclicos/química , Teoria Quântica , Cromatografia Líquida de Alta Pressão , Hidrocarbonetos Alicíclicos/síntese química , Cinética , Estrutura Molecular , Estereoisomerismo , Termodinâmica
15.
J Org Chem ; 77(2): 1202-7, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22208771

RESUMO

The alkylation of dienolates generated from 3-methoxycycloalk-2-enones having a 3'-hydroxyl alkenyl chain provides the corresponding quaternized cycloalkenones in a highly diastereoselective manner. The high degree of stereocontrol in the α-quaternization possibly implies intervention of a rigid chelating transition state that allows an efficient 1,4-asymmetric induction to take place.


Assuntos
Técnicas de Química Sintética/métodos , Hidrocarbonetos Alicíclicos/química , Alquilação , Hidrocarbonetos Alicíclicos/síntese química , Estrutura Molecular , Estereoisomerismo
16.
Ecotoxicology ; 21(3): 730-49, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22143384

RESUMO

Mussels Mytilus galloprovincialis were cross-transplanted at South Portugal from a reference site (site 1) to a site more contaminated with hydrocarbon compounds (site 2), and vice versa, in an active biomonitoring (ABM) concept, to assess the biotransformation capacity catalyzed by the mixed function oxygenase (MFO) system. Total alkanes (TAlk), the unresolved complex mixture (UCM), and total polycyclic aromatic hydrocarbons (TPAHs) concentration increased respectively 6, 4.4 and 4.2 fold relatively to control, in mussels transplanted from site 1 to 2. In the cross-transplant, a 48, 57 and 62% depuration of TAlk, UCM and TPAHs concentrations occurred by the end of the 3-4th week. Petrogenic and biogenic (marine and terrigenous) sources of AHs, and petrogenic and pyrolitic (biomass and oil/fuel incomplete combustion) sources of PAHs were detected at both sites. CYP450, CYT b (5) and NADPH-RED in mussels transplanted from site 1 to 2 were induced from day 0 to 28, with a total increase of 35, 32 and 35%, respectively, while biochemical equilibrium to lesser environmental contamination occurs in mussels transplanted from site 2 to 1. A significant relationship between CYP450 and NADPH-RED was found with TPAH, with distinctive behavior at the two sites. MFO system components increase with exposure time at one site and decreases in the other, reflecting an adaptation to distinct environmental hydrocarbon loads. The ABM strategy proved to be useful to understand the environment real impact on the biochemical responses in mussels' local populations. In this study, CYP450 and NADPH-RED are a useful biomarker for hydrocarbon exposure.


Assuntos
Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Hidrocarbonetos Alicíclicos/toxicidade , Mytilus/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Biotransformação , Carga Corporal (Radioterapia) , Sistema Enzimático do Citocromo P-450/metabolismo , Citocromos b5/efeitos dos fármacos , Citocromos b5/metabolismo , Monitoramento Ambiental , Hidrocarbonetos Alicíclicos/farmacocinética , NADPH Oxidases/efeitos dos fármacos , NADPH Oxidases/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/farmacocinética , Portugal , Água do Mar , Poluentes Químicos da Água/farmacocinética
17.
Appl Environ Microbiol ; 77(23): 8280-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21965391

RESUMO

The metabolically versatile Rhodococcus sp. strain DK17 is able to grow on tetralin and indan but cannot use their respective desaturated counterparts, 1,2-dihydronaphthalene and indene, as sole carbon and energy sources. Metabolite analyses by gas chromatography-mass spectrometry and nuclear magnetic resonance spectrometry clearly show that (i) the meta-cleavage dioxygenase mutant strain DK180 accumulates 5,6,7,8-tetrahydro-1,2-naphthalene diol, 1,2-indene diol, and 3,4-dihydro-naphthalene-1,2-diol from tetralin, indene, and 1,2-dihydronaphthalene, respectively, and (ii) when expressed in Escherichia coli, the DK17 o-xylene dioxygenase transforms tetralin, indene, and 1,2-dihydronaphthalene into tetralin cis-dihydrodiol, indan-1,2-diol, and cis-1,2-dihydroxy-1,2,3,4-tetrahydronaphthalene, respectively. Tetralin, which is activated by aromatic hydroxylation, is degraded successfully via the ring cleavage pathway to support growth of DK17. Indene and 1,2-dihydronaphthalene do not serve as growth substrates because DK17 hydroxylates them on the alicyclic ring and further metabolism results in a dead-end metabolite. This study reveals that aromatic hydroxylation is a prerequisite for proper degradation of bicyclics with aromatic and alicyclic rings by DK17 and confirms the unique ability of the DK17 o-xylene dioxygenase to perform distinct regioselective hydroxylations.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Hidrocarbonetos Alicíclicos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Rhodococcus/metabolismo , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Expressão Gênica , Espectroscopia de Ressonância Magnética , Rhodococcus/química , Rhodococcus/enzimologia , Rhodococcus/genética
18.
Aquat Toxicol ; 105(3-4): 652-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21963596

RESUMO

Understanding the toxic mechanisms by which organisms cope to environmental stressful conditions is a fundamental question for ecotoxicology. In this study, we evaluated biochemical responses and hydrocarbons bioaccumulation of the mangrove oyster Crassostrea brasiliana exposed for 96 h to four sublethal concentrations of diesel fuel water-accommodated fraction (WAF). For that purpose, enzymatic activities (SOD, CAT, GPx, GR, G6PDH, GST and GGT), HSP60 and HSP90 immunocontent and lipid peroxidation (LPO) levels were determined in the gill and digestive gland of oysters and related to the hydrocarbons accumulated in the whole soft tissues. The results of this study revealed clear biochemical responses to diesel fuel WAF exposure in both tissues of the oyster. The capacity of C. brasiliana to bioaccumulate aliphatic and aromatic hydrocarbons in a dose-dependent manner is a strong indication of its suitability as a model in biomonitoring programs along the Brazilian coast, which was also validated by the response of the antioxidant defenses, phase II biotransformation and chaperones. HSP60 levels and GGT activity were the most promising biomarkers in the gill, while GST and GR activities stood out as suitable biomarkers for the detection of diesel toxicity in the digestive gland. The decrease of SOD activity and HSP90 levels may also reflect a negative effect of diesel exposure regardless the tissue. The present results provide a sound preliminary report on the biochemical responses of C. brasiliana challenged with a petroleum by-product and should be carefully considered for use in the monitoring of oil and gas activities in Brazil.


Assuntos
Crassostrea/metabolismo , Gasolina/toxicidade , Hidrocarbonetos Alicíclicos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Relação Dose-Resposta a Droga , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Hidrocarbonetos Alicíclicos/farmacocinética , Peroxidação de Lipídeos/efeitos dos fármacos , Desintoxicação Metabólica Fase II , Estresse Oxidativo , Hidrocarbonetos Policíclicos Aromáticos/farmacocinética , Análise de Componente Principal , Poluentes Químicos da Água/farmacocinética
20.
Chem Commun (Camb) ; 47(17): 4968-70, 2011 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-21423990

RESUMO

A super-paddlewheel (comprised of two paddlewheels) metal-organic polyhedron (MOP) containing surface hydroxyl groups was synthesized and characterized. Condensation reactions with linear alkyl anhydrides lead to new MOPs with enhanced solubility. As a result, the surface-modified MOP 4 was demonstrated as a homogeneous Lewis-acid catalyst.


Assuntos
Hidrocarbonetos Alicíclicos/síntese química , Metais/química , Alquilação , Anidridos/química , Catálise , Cobre/química , Ciclopropanos , Hidrocarbonetos Alicíclicos/análise , Hidroxilação , Conformação Molecular , Solubilidade , Propriedades de Superfície
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