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1.
Biochim Biophys Acta ; 1081(3): 274-8, 1991 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-1847833

RESUMO

A monoclonal antibody (1A-LDR1) against sulfidopeptide leukotrienes (LT) is described. The mAb shows a nearly identical detection limit of about 0.04 ng for LTC4, LTD4, LTE4 and NacLTE4 in standard fluid phase RIA. Steric modifications, however, diminish the sensitivity, as determined for the examples 5-epi-LTC4, 6-epi-LTC4, 5,6-epi-LTC4 and 11-trans-LTC4. No crossreactivity could be observed for LTB4. Crossreactions with components of the LT peptide chain such as L-cysteine or glutathione, as well as with arachidonic acid, were not detectable. In assessing the accuracy of the LT-RIA, recovery experiments with supernatants of mouse peritoneal macrophages and incubates of gastric mucosa showed a good correlation of r = 0.993 and 0.990, respectively. Results of an inhibition experiment with mouse peritoneal macrophages, incubated with several concentrations of indomethacin and nordihydroguaiaretic acid (NDGA), support the reliability of RIA and ELISA. The new LT-mAB allows an almost complete detection of peptide leukotrienes in one assay.


Assuntos
Anticorpos Monoclonais , SRS-A/análogos & derivados , SRS-A/imunologia , Animais , Calcimicina/farmacologia , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Hibridomas , Indometacina/farmacologia , Leucotrieno E4 , Macrófagos/efeitos dos fármacos , Masoprocol/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Radioimunoensaio
2.
Phytochemistry ; 46(7): 1169-72, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9423289

RESUMO

The flower scents of 11 bat-pollinated plant species have been investigated using the 'closed-loop-stripping'-adsorption technique. GC and GC/MS analyses of the headspace samples resulted in the identification of 49 compounds, comprising amongst others sulphur compounds, terpenoids and aliphatic compounds.


Assuntos
Quirópteros , Odorantes , Pólen/química , Animais , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Reprodução , Enxofre/análise , Terpenos/análise
3.
Physiol Behav ; 61(6): 957-61, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9177572

RESUMO

Human urine samples were fractionated to examine the contribution of volatiles to the individual body odor. The samples were obtained from 4 male donors and fractionated using a vacuum technique. The volatiles from the chemical fractions were analyzed using the CLSA technique and gas chromatography. Thereafter, these fractions were tested in a computer-controlled olfactometer by trained rats. Although the rats were able to discriminate the distillation residue, they could not recognize the urine odor in the distilled fraction. The results of gas chromatography indicate a continuous release of volatile constituents in the distillation residue.


Assuntos
Odorantes , Urina/química , Adulto , Bioensaio , Fracionamento Químico , Humanos , Masculino
4.
Z Naturforsch C J Biosci ; 51(11-12): 849-52, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9081288

RESUMO

Different techniques like "closed loop stripping" [CLSA], "purge and trap" [PTI], and continuous steam distillation extraction [SDE] were used to establish GC profiles of major histocompatibility complex-associated volatile constituents of human urine and statistically evaluated for reliability. Of the three methods investigated, PTI appeared to be superior for the detection of very volatile substances, whereas SDE was the most efficient one with respect to yield. A number of short to medium-chain ketones, 4-hydroxy-3-methoxy-styrene, menthol and nicotine were identified in preliminary analyses.


Assuntos
Urinálise/instrumentação , Urinálise/métodos , Cromatografia Gasosa/métodos , Guaiacol/análogos & derivados , Guaiacol/urina , Humanos , Cetonas/urina , Mentol/urina , Nicotina/urina , Volatilização
5.
Z Naturforsch C J Biosci ; 56(7-8): 575-80, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11531092

RESUMO

The repellence of Aristolochia aff. orbicularis root, a native of Xochipala, Guerrero, Mexico, to the corn borer Sitophilus zeamais (Coleoptera) was investigated. The essential oil was isolated from the aromatic root and its repellent effect was assessed. About 40 components of the oil were identified using gas chromatography-mass spectrometry and other spectroscopic methods. The repellence of the roots, the oil and the chromatography fractions were also evaluated. Some fractions had a higher repellence than the total oil.


Assuntos
Besouros , Cycadopsida/química , Óleos Voláteis/farmacologia , Controle Biológico de Vetores , Raízes de Plantas/química , Animais , Bioensaio , Feminino , Masculino , México , Odorantes , Óleos Voláteis/isolamento & purificação , Zea mays/parasitologia
8.
Eicosanoids ; 5 Suppl: S1-3, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1333249

RESUMO

Some general synthetic routes for the synthesis of cysteinyl-leukotriene derivatives derived from stable building blocks are described. D6-LTE4, a metabolically stable isotopically labelled mass spectrometric internal standard, 20-hydroxy-LTE4, the unnatural 6-epi-LTE4; LTE3, a LT-derivative with 2-amino-thiophenol as a modified "amino-acid" and 14,15-dehydro-LTA4 were prepared. The compounds were tested in a LT-inhibition assay using a monoclonal antibody.


Assuntos
Leucotrienos/síntese química , Deutério , Leucotrieno A4 , Leucotrieno E4 , Leucotrienos/química , Conformação Molecular , Estrutura Molecular , SRS-A/análogos & derivados , SRS-A/síntese química , SRS-A/química
9.
Experientia ; 33(7): 874-5, 1977 Jul 15.
Artigo em Alemão | MEDLINE | ID: mdl-891760

RESUMO

By gaschromatographic-mass spectrometric methods 2-phenylethyl alcohol, benzylalcohol, phenylacetaldehyde and benzaldehyde were identified from scent brushes of male Noctuidae species (Lepidoptera).


Assuntos
Lepidópteros/análise , Feromônios/análise , Animais , Cromatografia Gasosa , Masculino , Espectrometria de Massas
10.
Planta Med ; 60(4): 318-22, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7938265

RESUMO

Extracts from Petasites hybridus were found to inhibit peptido-leukotriene biosynthesis in isolated peritoneal macrophages. Chemical analysis by gas chromatography coupled with mass and infrared spectroscopy facilitated the identification of three isomeric oxopetasan esters, petasin, and isopetasin as the main compounds of these extracts. Fractionations obtained by column chromatography of the most effective extract indicated a correlation between peptido-leukotriene biosynthesis inhibition and the content of isopetasin, a sesquiterpene ester of isopetasol and angelic acid, as well as the isomeric oxopetasan esters. Petasin, a structural isomer of isopetasin, however, was found to be inactive. It may even reduce the peptido-leukotrine inhibitory effect of isopetasin. It is concluded that isopetasin and the oxopetasan esters in Petasites hybridus inhibit the biosynthesis of the vasoconstrictive peptido-leukotrienes. This effect may contribute to some of the medicinal properties of Petasites hybridus extracts such as, e.g., gastroprotection and spasmolytic activity.


Assuntos
Leucotrienos/biossíntese , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Células Cultivadas , Cromatografia Gasosa-Espectrometria de Massas , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Extratos Vegetais/isolamento & purificação
11.
Z Naturforsch C Biosci ; 30(2): 283-93, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-125976

RESUMO

Electroantennogram (EAG) data reflecting response spectra of male pheromone receptors have been analyzed for 16 species of Noctuidae (Lepidoptera). The test compounds included 100 pheromone analogues, altered in chain length, in position and configuration of double bond(s), and in the functional end groups. On comparison of amounts of substance required to elicit an equivalent EAG response, a single compound was determined to be most effective on a given species: these structures, either known or proposed as the natural sex pheromones of the species, were cis-7-dodecen-1-y1 acetate, cis-7-tetradecen-1-y1 acetate, cis-9-tetradecen-1-yu acetate, trans-9-tetradecen-1-y1 acetate, cis-11-hexadecen-1-y1 acetate, cis-9, trans-12-tetradecadien-1-y1 acetate, cis-9-tetradecen-1-y1 formate, and cis-9-tetradecen-1-ol, respectively. Elongation (shortening) of the chain by 1 or 2 methylene groups, the movement of a double bond 1 carbon from the optimum, a change to the opposite geometrical isomer, or the introduction of a second double bond invariably reduced EAG responses to 1.8 to 56 times below that observed with the most stimulating compound, in all 16 species. Further alterations in chain length or in double bond position caused even greater reduction in activity, as did certain in end group (Tables I and II). A set of distinct rules could be derived from these structure-response relationships; one of these rules concerns the optimum position of the double bond(s) in relation to chain length, and another one the ratios in activity values produced by end group variations, irrespective of chain length. The same rules described here for 16 noctuid species held also for the structure-response relationships observed within various additional groups of Lepidoptera. From EAG values determined in this study, an attempt has been made to calculate physicochemical propteries of underlying acceptor structures.


Assuntos
Lepidópteros/fisiologia , Mariposas/fisiologia , Nervo Olfatório/fisiologia , Feromônios/fisiologia , Células Receptoras Sensoriais/fisiologia , Animais , Masculino , Relação Estrutura-Atividade
12.
Naturwissenschaften ; 87(7): 320-2, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11013881

RESUMO

The myrmicine ant Mayriella overbecki lays recruitment trails during foraging and nest emigrations. The trail pheromone originates from the poison gland. From ten identified components of the poison gland secretions only methyl 6-methylsalicylate 1 elicited trail following behavior.


Assuntos
Formigas/fisiologia , Comportamento Animal/fisiologia , Feromônios/fisiologia , Salicilatos/isolamento & purificação , Animais , Comportamento Animal/efeitos dos fármacos , Glândulas Exócrinas/metabolismo , Comportamento Alimentar , Feromônios/isolamento & purificação , Feromônios/farmacologia , Salicilatos/farmacologia
13.
Naturwissenschaften ; 87(8): 377-80, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11013893

RESUMO

The ant Eutetramorium mocquerysi (Myrmicinae) is endemic to the island of Madagascar. During foraging and nest emigration the ants lay recruitment trails with secretions from the poison gland. We identified three pyrazine compounds in the poison gland secretion: 2,3-dimethyl-5-(2-methylpropyl)pyrazine 1, 2,3-dimethyl-5-(3-methylbutyl)pyrazine 3, 2,3-dimethyl-5-(2-methylbutyl)pyrazine 4. Only the first component elicited trail-following behavior in the ants. We were unable to investigate whether the other pyrazine components have a synergistic function.


Assuntos
Formigas/fisiologia , Feromônios/química , Pirazinas/metabolismo , Comportamento Social , Animais , Glândulas Exócrinas/metabolismo , Comportamento Alimentar/fisiologia , Locomoção/fisiologia , Madagáscar , Feromônios/metabolismo , Pirazinas/análise , Pirazinas/química
14.
J Chem Ecol ; 21(12): 1947-55, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24233898

RESUMO

By means of gas chromatographic, mass spectrometric, and micro-preparative methodsN,N-dimethyluracil and actinidine were identified as two ethologically active compounds in the ponerine antMegaponera foetens. The synthesized poison gland compoundN,N-dimethyluracil released trail-following behavior, whereas actinidine, found in the pygidial gland, stimulated ants to leave the nest, possibly in an alarm reaction. Biological activity of the synthetic samples were confirmed by behavioral experiments and electroantennogram responses with worker antennae.

15.
J Comp Physiol A ; 186(2): 143-53, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10707312

RESUMO

We tested the attractiveness of individual scent compounds of bat-pollinated flowers to their pollinators, small flower-visiting bats of the genus Glossophaga (Phyllostomidae). Twenty compounds belonging to four different chemical substance classes were tested, both in the laboratory and in the field. In the laboratory, the bats (Glossophaga soricina) approached odour sources spontaneously and without preceding experience. Without ever receiving any reward they preferred the scent of a sulphur-containing compound, dimethyl disulphide, to several other odour components emitted by bat-pollinated flowers, and to scentless controls. In the field, at La Selva station in the tropical lowland rain forest of Costa Rica, G. commissarisi were attracted by two sulphur-containing compounds, dimethyl disulphide and 2,4-dithiapentane, to visit artificial flowers filled with sugar water. Thus, in nectarivorous bats the sense of smell obviously plays an important role in searching for and localising food sources, and even single components of the scent bouquets of bat-pollinated flowers are attractive. The preference for sulphur-containing odours seems to be innate.


Assuntos
Quirópteros/fisiologia , Dissulfetos , Comportamento Alimentar/fisiologia , Orientação/fisiologia , Olfato/fisiologia , Animais , Aprendizagem por Discriminação/fisiologia , Odorantes , Perfumes , Extratos Vegetais/química , Pólen , Compostos de Enxofre/química
16.
J Chem Ecol ; 13(5): 1299-311, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-24302150

RESUMO

The structure elucidation of sex pheromones of Lepidoptera by a solid-sample injection technique in conjunction with capillary gas chromatography is described. The applicability of this method in GC and GC-MS modes was demonstrated by reanalyzing the sex attractants of females ofOstrinia nubilalis andBombyx mori. The pheromone complex ofMamestra brassicae was reinvestigated and (Z)-9-hexadecenyl acetate and (Z)-11-hexadecenol were found in addition to already known pheromone components of this species. By using the solid-sample injection, the exact site of pheromone release could be determined inM. brassicae.

17.
J Chem Ecol ; 15(1): 317-28, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24271446

RESUMO

The secretion of the hypertrophied metapleural gland of the antCrematogaster deformis contains a mixture of phenols, consisting mainly of 3-propylphenol, 3-pentylphenol, 3,4-dihydro-8-hydroxy-3-methylisocoumarin (mellein), 5-propylresorcinol, and 5-pentylresorcinol. The secretion is released, as a repellent, when the highly vulnerable petiolar-postpetiolar region of the abdomen is attacked by enemy ants. In addition, small amounts of the secretion are released regularly to serve as an antiseptic, which is considered the original function of the gland. The secretion also has some insecticidal properties.

18.
J Chem Ecol ; 14(2): 683-90, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24276010

RESUMO

Moths belonging to the speciesSpodoptera sunia have been recognized as a new pest of cotton in Central America. By means of electro-physiologic investigations, solid sample injection gas chromatography, and combined gas chromatography-mass spectrometry, (Z)-9-tetradecenyl acetate, (9Z,12E)-9,12-tetradecadienyl acetate, (Z)-9-tetradecen-1-ol, and (Z)-11-hexadecenyl acetate, in a ratio of 100∶5∶31∶20, were identified in the pheromone gland of female insects. These substances should serve as a base for the development of a pheromone-monitoring system for this lepidopteran pest.

19.
Planta Med ; 63(1): 88-90, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17252334

RESUMO

The volatile constituents of the essential oil from Elsholtzia flava Benth. growing in higher elevations of Kumaon region (India) were characterized by combination of GC, GC-MS, GC-FT-IR and NMR. Twenty-two components were identified comprising 93% of the oil. Rose furan (45.0%) and estragol (40.5%) were the major constituents.

20.
Bioorg Med Chem ; 4(3): 473-7, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8733629

RESUMO

Conformational analyses of (Z)-5-decenylacetate, a sex pheromone component of the turnip moth, Agrotis segetum, and double unsaturated pheromone analogues 4 and 5 have been performed by ab initio calculations using Gaussian 92. Two minima were found for a cisoid and a transoid conformer, differing for 0.03 kcal/mol only. Conformational energies of diene analogues (5Z,7E)-5,7-decadienyl acetate (4) and (3E,5Z)-3,5,-decadienyl acetate (5) were determined for conformers required to mimic spatial relationships of the cisoid conformation of the natural pheromone 2. Finally, single sensillum recording studies were carried out with chain elongated C11- to C16-pheromone analogues 6.


Assuntos
Acetatos/química , Mariposas/química , Atrativos Sexuais/química , Potenciais de Ação , Animais , Eletrofisiologia , Modelos Moleculares , Relação Estrutura-Atividade
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