RESUMO
Defensive secretions of millipedes are remarkable for containing toxic quinones known to efficiently repell hematophagous arthropods. Here we show that Endangered blonde capuchin monkeys make use of such secretions. We (i) describe the anointing behavior performed by the monkeys (ii) identify the millipede species used in the process (iii) describe the volatile chemical composition of its secretion. The blonde capuchin monkeys selectively searched for millipedes hidden under the ground. We observed three bouts of anointing behavior, performed by 13 individuals of all age classes (from adults to independent infants), both solitarily (1 event) and socially (10 events). The only millipede species used by the monkeys is an undescribed species of the genus Poecilocricus (Spirobolida, Rhinocricidae). The volatile chemical composition of the secretions was predominantly comprised of a mixture of benzoquinones and hydroquinones. The social nature of the behavior and time of the observations (mosquito season), suggest that social bonding and mosquito avoidance is linked to the anointing behavior of the monkeys.
Assuntos
Artrópodes/metabolismo , Comportamento Animal/efeitos dos fármacos , Benzoquinonas/farmacologia , Cebus/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Hidroquinonas/farmacologia , Animais , Artrópodes/química , Benzoquinonas/isolamento & purificação , Hidroquinonas/isolamento & purificação , Comportamento SocialRESUMO
As a part of an ongoing bioprospective project, searching for potential medicinal plants from the Brazilian Atlantic Forest, Miconia willdenowii was selected for its potential leishmanicidal and antimicrobial activities. The crude ethanolic extract of M. willdenowii showed an inhibition of 99.7% of the promastigote forms of Leishmania amazonensis at the concentration of 80⯵g/mL. Further investigation of its antimicrobial activity against pathogenic fungi and Gram positive and negative bacteria, revealed a significant antimicrobial activity. A bioguided study with its liquid-liquid partition fractions revealed the hexane fraction (Hex) as the most active against Leishmania, inhibiting 99.2% and 46.9% of the protozoan at concentrations of 40 and 20⯵g/mL, respectively. Hex also showed significant antimicrobial activity against Staphylococcus aureus and Candida krusei with IC50 of 15.6 and 62.5⯵g/mL, respectively. Purification of Hex led to the isolation of 2-methoxy-6-pentyl-benzoquinone (1, also known as primin) as the active metabolite, probably responsible for the observed antimicrobial and anti-leishmania effects. Primin (1) disclosed leishmanicidal activity (IC50â¯=â¯1.25⯵M), showing higher potency than the standard drug amphotericin B (IC50â¯=â¯5.08⯵M), with additional antifungal effects against all tested fungi species. Compound 1 also showed significant activity against S. aureus (IC50â¯=â¯8.94⯵M), showing a comparable potency with the reference drug chloramphenicol (IC50â¯=â¯6.19⯵M), but with a potential cytotoxicity towards peripheral human blood mononuclear cells (CC50â¯=â¯255.15⯵M). Here in, the antimicrobial and anti-L. amazonensis effects of M. willdenowii are reported for the first time, as well as Primin (1) as its probable bioactive metabolite.
Assuntos
Antibacterianos/farmacologia , Antiprotozoários/farmacologia , Benzoquinonas/farmacologia , Melastomataceae/química , Extratos Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Antiprotozoários/isolamento & purificação , Benzoquinonas/isolamento & purificação , Brasil , Humanos , Leishmania/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Folhas de Planta/química , Plantas Medicinais/química , Staphylococcus aureus/efeitos dos fármacosRESUMO
The bioassay-guided fractionation of the ethyl acetate extract of the fungus Cochliobolus sp. highlighted leishmanicidal activity and allowed for anhydrocochlioquinone A (ANDC-A) isolation. MS, 1D and 2D NMR spectra of this compound were in agreement with those published in the literature. ANDC-A exhibited leishmanicidal activity with EC 50 value of 22.4 microgram/mL (44 mu M) and, when submitted to the microdilution assay against Gram-ositive and Gram-negative bacteria, showed a minimal inhibitory concentration against Staphylococcus aureus ATCC 25295 of 128 microgram/mL (248.7 mu M). It was also active against five human cancer cell lines, showing IC50 values from 5.4 to 20.3 mu M. ANDC-A demonstrated a differential selectivity for HL-60 (SI 5.5) and THP-1 (SI 4.3) cell lines in comparison with Vero cells and was more selective than cisplatin and doxorubicin against MCF-7 cell line in comparison with human peripheral blood mononuclear cells. ANDC-A was able to eradicate clonogenic tumour cells at concentrations of 20 and 50 mu M and induced apoptosis in all tumour cell lines at 20 mu M. These results suggest that ANDC-A might be used as a biochemical tool in the study of tumour cells biochemistry as well as an anticancer agent with durable effects on tumours.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antiprotozoários/farmacologia , Ascomicetos/química , Benzoquinonas/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Ascomicetos/metabolismo , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Células HCT116 , Células HL-60 , Humanos , Células Jurkat , Klebsiella oxytoca/efeitos dos fármacos , Klebsiella oxytoca/crescimento & desenvolvimento , Leishmania mexicana/efeitos dos fármacos , Leishmania mexicana/crescimento & desenvolvimento , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Células MCF-7 , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Células THP-1 , Células VeroRESUMO
Five new meroterpenoid compounds designed as rel-10ß,11ß-epoxy-2,11-dimethoxy-8α-hydroxy-8aß-methyl-5α,6,7,8,8a,9,10,10aß-octahydro-1,4-anthracendione (1), rel-10ß,11ß-epoxy-8α,5-dihydroxy-2-methoxy-8aß-methyl-5,6,7,8,8a,9,10,10aß-octahydro -1.4-anthracendione (2), rel-1,4,8α-trihydroxy-5-furanyl-2-methoxy-8aß-methyl-6,7,8, 8a,9,10-hexahydro-10-anthracenone (3), rel-10α,11α-epoxy-8α,11ß-dihydroxy-8aß-methyl-5ß,6,7,8,8a,9,10,10aß-octahydro-1,4-anthracenediol (4) and rel-1,4,8α-trihydroxy-5-carboxyethyl-2-methoxy-8aß-methyl-6,7,8,8a,9,10-hexahydro-10-anthra-cenone (5), besides seven (6-12) known compounds were isolated from the heartwood and sapwood ethanol extracts of Cordia oncocalyx. Moreover, the main isolated compounds were screened using the electrically driven mice vas deferens bioassay, which has a rich pharmacological receptors diversity.
Assuntos
Benzoquinonas/química , Cordia/química , Hidroquinonas/química , Contração Muscular/efeitos dos fármacos , Terpenos/química , Animais , Benzoquinonas/isolamento & purificação , Hidroquinonas/isolamento & purificação , Técnicas In Vitro , Masculino , Camundongos , Estrutura Molecular , Terpenos/isolamento & purificação , Ducto Deferente/efeitos dos fármacosRESUMO
Jacaranda oxyphylla Cham. is popularly known as 'caroba-de-São-Paulo' and it is used in traditional medicine for microbial infections. A new phytoquinoid (α/ß-glucoside-4-phenylacetate-6-(1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate) (1) was isolated from J. oxyphylla leaves, together with three known compounds: quercetin-3-O-ß-d-galactoside (2), verbascoside (3) and polystyrene (4). Their chemical structures were elucidated using spectroscopic techniques and by comparison with the related known compounds. In addition, it was found a pronounced acetylcholinesterase inhibitory activity for the quinoid 1 (100.0 ± 0.8%) and phenolic compounds 2 and 3 (99.9 ± 0.7 and 99.3 ± 0.5%, respectively), if compared to the standard eserine (92.7 ± 0.4%), that was analysed by a microplate spectrophotometer.
Assuntos
Benzoquinonas/isolamento & purificação , Bignoniaceae/química , Glucosídeos/isolamento & purificação , Anti-Infecciosos/farmacologia , Benzoquinonas/química , Benzoquinonas/farmacologia , Inibidores da Colinesterase/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Folhas de Planta/químicaRESUMO
Lung cancer is the leading cause of cancer deaths in the world. Disease stage is the most relevant factor influencing mortality. Unfortunately, most patients are still diagnosed at an advanced stage and their five-year survival rate is only 4%. Thus, it is relevant to identify novel drugs that can improve the treatment options for lung cancer. Natural products have been an important source for the discovery of new compounds with pharmacological potential including antineoplastic agents. We have previously isolated a prenylated benzophenone (7-epiclusianone) from Garcinia brasiliensis (Clusiaceae) that has several biological properties including antiproliferative activity against cancer cell lines. In continuation with our studies, the present work aimed to investigate the mechanisms involved with antiproliferative activity of 7-epiclusianone in A549 cells. Our data showed that 7-epiclusianone reduced the viability of A549 cells in a concentration-dependent manner (IC50 of 16.13 ± 1.12 µM). Cells were arrested in G1/S transition and apoptosis was induced. In addition, we observed morphological changes with cytoskeleton disorganization in consequence of the treatment. Taken together, the results showed that cell cycle arrest in G1/S transition is the main mechanism involved with antiproliferative activity of 7-epiclusianone. Our results are promising and open up the prospect of using this compound in further anticancer in vivo studies.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzofenonas/farmacologia , Benzoquinonas/farmacologia , Células Epiteliais/efeitos dos fármacos , Frutas/química , Garcinia/química , Mucosa Respiratória/efeitos dos fármacos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Benzofenonas/química , Benzofenonas/isolamento & purificação , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/ultraestrutura , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Extratos Vegetais/química , Mucosa Respiratória/metabolismo , Mucosa Respiratória/ultraestruturaRESUMO
Praziquantel is the drug of choice for the treatment of schistosomiasis. However, several strains of Schistosoma mansoni are resistant to praziquantel, making it necessary to discover new drugs that might be used for its treatment. With this in mind, the properties of a schistosomicidal ethanolic extract of Garcinia brasiliensis Mart. epicarp, the fractions obtained by partitioning this extract, including the hexane fractions, ethyl acetate fraction, and the aqueous fraction, and the isolated compounds 7-epiclusianone, a major component from these fractions, and fukugetin were tested in vitro on adult worms of S. mansoni. Mortality, damage to membranes, and excretory system activity were observed at 100.0, 50.0, 75.0, and 14.0 µg/mL for the ethanolic extract of G. brasiliensis Mart. epicarp, its hexane fractions, the ethyl acetate fraction, and 7-epiclusianone, respectively. For 7-epiclusianone, these data were confirmed by fluorescent probe Hoechst 33â258 and resorufin. Additionally, the biocidal effect of 7-epiclusianone was even higher than the hexane fractions. Moreover, an inhibitory effect of 7-epiclusianone on the egg laying of female adult S. mansoni worms was observed in cercariae and schistossomula. Thus, 7-epiclusianone is a promising schistosomicidal compound; however, more studies are needed to elucidate its mechanism of toxicity and to evaluate the in vivo activity of this compound.
Assuntos
Benzofenonas/farmacologia , Benzoquinonas/farmacologia , Garcinia/química , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose/tratamento farmacológico , Esquistossomicidas/farmacologia , Animais , Benzofenonas/química , Benzofenonas/isolamento & purificação , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Biflavonoides/farmacologia , Feminino , Masculino , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Esquistossomicidas/química , Esquistossomicidas/isolamento & purificaçãoRESUMO
Human African trypanosomiasis is a neglected tropical disease in sub Saharan Africa that is fatal if left untreated. In a search for new natural products with antitrypanosomal activity, we recently identified abruquinones B and I from Abrus precatorius as potent in vitro trypanocidal compounds with high selectivity indices. To obtain sufficient compound for in vivo efficacy tests in mice, a second batch of plant material was re-collected and extracted. However, the chemical profiles of the two batches differed, and additional abruquinones were isolated and identified by HR-ESI-MS, and 1D and 2D NMR ((1)H, (13)C, COSY, HMBC, HSQC, and NOESY) spectroscopy. Abruquinones J (1), K (2), and L (3) were new, while abruquinones A (4) and D (5) were known from the first batch of plant material. The absolute configuration of compounds 1 to 3 was determined by comparison of electronic circular dichroism (ECD) spectra with calculated ECD data. Compounds 2 to 5 showed high in vitro activity against T. b. rhodesiense (IC50 of 0.01, 0.02, 0.02 and 0.01 µM, respectively), and remarkable SIs of 508, 374, 1379, and 668, respectively.
Assuntos
Abrus/química , Tripanossomicidas/isolamento & purificação , Animais , Benzopiranos/isolamento & purificação , Benzopiranos/toxicidade , Benzoquinonas/isolamento & purificação , Benzoquinonas/toxicidade , Testes de Sensibilidade Microbiana , RatosRESUMO
Leishmaniasis, Chagas disease, and malaria affect the poorest population around the world, with an elevated mortality and morbidity. In addition, the therapeutic alternatives are usually toxic or ineffective drugs especially those against the trypanosomatids. In the course of selection of new anti-protozoal compounds from Brazilian flora, the CH(2)C(l2) phase from MeOH extract obtained from the leaves of Pentacalia desiderabilis (Vell.) Cuatrec. (Asteraceae) showed in vitro anti-leishmanial, anti-malarial, and anti-trypanosomal activities. The chromatographic fractionation of the CH(2)Cl(2) phase led to the isolation of the bioactive compound, which was characterized as jacaranone [methyl (1-hydroxy-4-oxo-2,5-cyclohexandienyl)acetate], by spectroscopic methods. This compound showed activity against promastigotes of Leishmania (L.) chagasi, Leishmania (V.) braziliensis, and Leishmania (L.). amazonensis showing an IC(50) of 17.22, 12.93, and 11.86 µg/mL, respectively. Jacaranone was also tested in vitro against the Trypanosoma cruzi trypomastigotes and Plasmodium falciparum chloroquine-resistant parasites (K1 strain) showing an IC(50) of 13 and 7.82 µg/mL, respectively, and was 3.5-fold more effective than benznidazole in anti-Trypanosoma cruzi assay. However, despite of the potential against promatigotes forms, this compound was not effective against amastigotes of L. (L.) chagasi and T. cruzi. The cytotoxicity study using Kidney Rhesus monkey cells, demonstrated that jacaranone showed selectivity against P. falciparum (21.75 µg/mL) and a selectivity index of 3. The obtained results suggested that jacaranone, as other similar secondary metabolites or synthetic analogs, might be useful tolls for drug design for in vivo studies against protozoan diseases.
Assuntos
Antiprotozoários/farmacologia , Asteraceae/química , Benzoquinonas/farmacologia , Leishmania/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiprotozoários/isolamento & purificação , Antiprotozoários/toxicidade , Benzoquinonas/isolamento & purificação , Benzoquinonas/toxicidade , Brasil , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia , Concentração Inibidora 50 , Macaca mulatta , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Folhas de Planta/química , Análise EspectralRESUMO
The aim of this study was to evaluate the effects of 7-epiclusianone (7-epi) on specific virulence attributes of Streptococcus mutans in vitro and on development of dental caries in vivo. 7-Epi was obtained and purified from fruits of Rheedia brasiliensis. We investigated its influence on surface-adsorbed glucosyltransferase (Gtf) B activity, acid production, and viability of S. MUTANS in biofilms, as well as on caries development using a rodent model. 7-Epi (100 µg/mL) significantly reduced the activity of surface-adsorbed GtfB (up to 48.0 ± 1.8 of inhibition at 100 µg/mL) and glycolytic pH-drop by S. mutans in biofilms (125 and 250 µg/mL) (vs. vehicle control, p < 0.05). In contrast, the test compound did not significantly affect the bacterial viability when compared to vehicle control (15 % ethanol, p > 0.05). Wistar rats treated topically with 7-epi (twice daily, 60-s exposure) showed significantly smaller number of and less severe smooth- and sulcal-surface carious lesions (p < 0.05), without reducing the S. mutans viable population from the animals' dental biofilms. In conclusion, the natural compound 7-epiclusianone may be a potentially novel pharmacological agent to prevent and control dental caries disease.
Assuntos
Benzofenonas/farmacologia , Benzoquinonas/farmacologia , Cárie Dentária/prevenção & controle , Streptococcus mutans/efeitos dos fármacos , Animais , Benzofenonas/química , Benzofenonas/isolamento & purificação , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Biofilmes/efeitos dos fármacos , Clusiaceae/química , Cárie Dentária/microbiologia , Glucanos/biossíntese , Glucosiltransferases/metabolismo , Concentração de Íons de Hidrogênio , Ratos , Streptococcus mutans/metabolismo , Streptococcus mutans/fisiologiaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Ternstroemia pringlei represents one of the most widely employed and commercially exploited medicinal plant in Mexico, used popularly as a tranquilizer and for the treatment of insomnia. AIM OF THE STUDY: To investigate the sedative constituents of the plant through a bio-guided fractionation of extracts derived from calyx and fruits. MATERIALS AND METHODS: Crude extracts with different polarities (CHCl(3), AcOEt, MeOH, aqueous) were prepared and subjected to chromatographic fractionation, leading to the isolation of the sedative compound (1) from the MeOH crude extract. The identity of 1 was unequivocally established by means of 1D and 2D NMR spectroscopic analysis. The sleeping time induced by sodium pentobarbital and the elevated plus-maze models were performed on mice to determine the sedative and anxiolytic activities, respectively. Bioactivity was also investigated though in vitro GABA release experiments using mice brain slices. RESULTS: The sedative compound was established as jacaranone (1), and its effect was clearly demonstrated through a dose-dependent response analysis (ED(50) = 25 mg/kg mouse weight). When tested in the elevated plus-maze model, none of the extracts from Ternstroemia pringlei displayed anxiolytic activity. GABA release experiments showed that the MeOH and aqueous crude extracts released this neurotransmitter at a ratio of 217 and 179 pmol/g protein, respectively, evidencing the presence of other bioactive constituents in the extracts apart of 1, whose activity was absent in this model. CONCLUSIONS: Although 1 has been isolated and identified in a number of plant species, this is the first time that its sedative effect has been demonstrated. No previous record exists of other sedative compounds having been isolated from Ternstroemia pringlei.
Assuntos
Benzoquinonas/isolamento & purificação , Benzoquinonas/uso terapêutico , Brassicaceae , Flores , Hipnóticos e Sedativos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Theaceae , Árvores , Animais , Ansiedade/tratamento farmacológico , Ansiedade/psicologia , Benzoquinonas/farmacologia , Relação Dose-Resposta a Droga , Hipnóticos e Sedativos/farmacologia , Hipnóticos e Sedativos/uso terapêutico , Masculino , México , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/farmacologiaRESUMO
The pericarp and seeds from fruits of Garcinia brasiliensis were subjected to extraction with hexane and ethanol. The pericarp hexane extract (PHE) and seed ethanol extract (SEE) were purified by silica gel column chromatography, which permitted isolation of the prenylated benzophenones 7-epiclusianone (1) and guttiferone-A (2), respectively. The antimicrobial activity of PHE, SEE, and compounds 1 and 2 were evaluated against Candida albicans, Staphylococcus aureus, Escherichia coli, and Bacillus cereus cultures. The minimum inhibitory concentration and minimum bactericidal concentration were established. The substances presented activity against S. aureus and B. cereus as follows: PHE, 4.0 microg/mL and 2.4 microg/mL; SEE, 10.0 microg/mL and 12.6 microg/mL; 7-epiclusianone, 1.2 microg/mL and 0.6 microg/mL; and guttiferone-A, 2.4 microg/mL and 2.4 microg/mL, respectively. The direct relationship between the lipophilic character of the structure and activity in Gram-positive bacteria was specifically observed. Therefore these extracts and prenylated benzophenones represent an interesting topic for further studies and open possibilities for an alternative control of diseases associated with Gram-positive bacteria.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Benzofenonas/farmacologia , Benzoquinonas/farmacologia , Garcinia , Floroglucinol/farmacologia , Extratos Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Bactérias/efeitos dos fármacos , Benzofenonas/isolamento & purificação , Benzoquinonas/isolamento & purificação , Candida albicans/efeitos dos fármacos , Frutas , Garcinia/química , Testes de Sensibilidade Microbiana , Floroglucinol/análogos & derivados , Floroglucinol/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , SementesRESUMO
Protozoan parasites belonging to genera Leishmania and Trypanosoma are the etiological agents of severe neglected tropical diseases (NTDs) that cause enormous social and economic impact in many countries of tropical and sub-tropical areas of the world. In our screening program for new drug leads from natural sources, we found that the crude extract of the endophytic fungus Cochliobolus sp. (UFMGCB-555) could kill 90% of the amastigote-like forms of Leishmania amazonensis and inhibit by 100% Ellman's reagent reduction in the trypanothione reductase (TryR) assay, when tested at 20 microg mL(-1). UFMGCB-555 was isolated from the plant Piptadenia adiantoides J.F. Macbr (Fabaceae) and identified based on the sequence of the internally transcribed spacer (ITS) regions of its ribosomal DNA. The chromatographic fractionation of the extract was guided by the TryR assay and resulted in the isolation of cochlioquinone A and isocochlioquinone A. Both compounds were active in the assay with L. amazonensis, disclosing EC(50) values (effective concentrations required to kill 50% of the parasite) of 1.7 microM (95% confidence interval = 1.6 to 1.9 microM) and 4.1 microM (95% confidence interval = 3.6 to 4.7 microM), respectively. These compounds were not active against three human cancer cell lines (MCF-7, TK-10, and UACC-62), indicating some degree of selectivity towards the parasites. These results suggest that cochlioquinones are attractive lead compounds that deserve further investigation aiming at developing new drugs to treat leishmaniasis. The findings also reinforce the role of endophytic fungi as an important source of compounds with potential to enter the pipeline for drug development against NTDs.
Assuntos
Ascomicetos , Fabaceae/microbiologia , Fabaceae/parasitologia , Leishmania mexicana/isolamento & purificação , Trypanosoma/isolamento & purificação , África Subsaariana , Animais , Ascomicetos/genética , Benzoquinonas/isolamento & purificação , Neoplasias da Mama/parasitologia , Linhagem Celular Tumoral , América Central , Primers do DNA , DNA Fúngico/genética , DNA Ribossômico/genética , Feminino , Humanos , Neoplasias Renais/parasitologia , Melanoma/parasitologia , NADH NADPH Oxirredutases/metabolismo , Proteínas Recombinantes/metabolismo , América do Sul , Esterol O-Aciltransferase/antagonistas & inibidores , Clima Tropical , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/isolamento & purificação , Organização Mundial da SaúdeRESUMO
Two alkylated 1,4-benzoquinones were identified from the defensive secretion produced by the neotropical harvestman Goniosoma longipes (Gonyleptidae). They were characterized as 2,3-dimethyl-1,4-benzoquinone and 2-ethyl-3-methyl-1,4-benzoquinone. We tested the effectiveness of these benzoquinone secretions against several predator types, including invertebrates and vertebrates. Different predators were exposed to the harvestmen's gland secretion or to distilled water in laboratory bioassays. Our results indicate that secretions containing the 1,4-benzoquinones released by G. longipes can be an effective defense against predation, and that the effectiveness of the secretion is dependent on the predator type. The scent gland secretion repelled seven ant species, two species of large wandering spiders, and one frog species, but was not an effective defense against an opossum. Our study also demonstrates that the scent gland secretion of G. longipes can work as a chemical shield preventing the approach of three large predatory ants for at least 10 min. The chemical shield may protect the harvestman against successive attacks of the same ant worker and also allow the harvestman to flee before massive ant recruitment. Our data support the suggestion that chemical defenses may increase survival with some but not all potential predators. This variation in defense effectiveness may result from many interacting factors, including the attack strategy, size, learning ability, and physiology of the predators, as well as the chemical nature of the defensive compounds, type of emission, and amount of effluent released by the prey.
Assuntos
Aracnídeos/química , Benzoquinonas/farmacologia , Comportamento Predatório/efeitos dos fármacos , Glândulas Odoríferas/metabolismo , Adaptação Fisiológica , Comunicação Animal , Animais , Benzoquinonas/isolamento & purificação , Cicloexenos , Invertebrados/efeitos dos fármacos , Glândulas Odoríferas/química , Fatores de Tempo , VertebradosRESUMO
The production of antimicrobial compounds by fungi associated with Clusia spp. pollinating bees (Trigona sp., Trigonini) was investigated in order to approach natural mechanisms of microbial density control within nest environment. By using a bioassay-guided approach based on bioautography and minimal inhibitory concentration (MIC), known alpha,beta-dehydrocurvularin and curvularin were isolated from Curvularia eragrostidis (CCT 5634) and Curvularia pallescens (CCT 5654), and known cochlioquinone A and isocochlioquinone A were isolated from Drechslera dematioidea (CCT 5631).
Assuntos
Antifúngicos/química , Abelhas/fisiologia , Clusia/química , Fungos/isolamento & purificação , Extratos Vegetais/química , Pólen/fisiologia , Animais , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Abelhas/microbiologia , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Benzoquinonas/farmacologia , Fungos/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologiaRESUMO
The benzoquinone embelin and four alkyl phenols were isolated from an Argentinean collection of Oxalis erythrorhiza. 3-Heptadecyl-5-methoxy-phenol is reported for the first time. The structures were determined by spectroscopic methods. Embelin presented inhibitory effect on methicillin-resistant Staphylococcus aureus, Escherichia coli and the dermatophytic fungi Epidermophyton floccosum, Microsporum canis, Microsporum gypseum, Trichophyton mentagrophytes and Trichophyton rubrum with MICs ranging between 50 and 100 microg/ml. Furthermore, embelin was active against Trypanosoma cruzi trypomastigotes with 100% lysis at 100 microg/ml and cytotoxicity below the trypanocidal concentration. The new alkyl phenol 3-heptadecyl-5-methoxy-phenol was active towards Leishmania amazonensis and Leishmania donovani promastigotes with 100% lysis at 100 microg/ml. The cytotoxicity (IC50) of embelin and the new alkyl phenol on human lung fibroblasts were 739 and 366 microM, respectively. The plant is used to treat heart complains, a symptomatology related to Chagas' disease which is endemic in the San Juan Province, Argentine.
Assuntos
Anti-Infecciosos/farmacologia , Benzoquinonas/farmacologia , Fenóis/farmacologia , Plantas Medicinais/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/toxicidade , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Antiprotozoários/toxicidade , Benzoquinonas/isolamento & purificação , Benzoquinonas/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Testes de Sensibilidade Parasitária , Fenóis/isolamento & purificação , Fenóis/toxicidade , Extratos Vegetais/farmacologiaRESUMO
Bioactivity-directed fractionation of an EtOAc extract from the leaves of Miconia lepidota afforded the two benzoquinones 2-methoxy-6-heptyl-1,4-benzoquinone (1) and 2-methoxy-6-pentyl-1,4-benzoquinone (primin) (2). This is the first reported isolation of 1. Both quinones 1 and 2 exhibited activity toward mutant yeast strains based on Saccharomyces cerevisiae, indicative of their cytotoxicity and potential anticancer activity. A number of previously synthesized and new analogues were prepared and tested in the same strains. Compounds 1, 2, 2-methoxy-6-butyl-1,4-benzoquinone (5), and 2-methoxy-6-decyl-1,4-benzoquinone (6) were tested in two cytotoxicity assays. In the M109 tumor cell lines, quinones 1, 2, and 6 had an IC(50) value of 10 microg/mL. In the A2780 cell line, compounds 1, 2 and 5 had IC(50) values of 7.9, 2.9, and 3.2 microg/mL, respectively.
Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Benzoquinonas/química , Benzoquinonas/farmacologia , Plantas Medicinais/química , Antineoplásicos Fitogênicos/isolamento & purificação , Benzoquinonas/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , Suriname , Células Tumorais Cultivadas , Leveduras/efeitos dos fármacosRESUMO
7-Epiclusianone, isolated from Rheedia gardneriana, was tested in several biological assays. It was active in vitro against trypomastigotes of Trypanosoma cruzi but inactive in vivo in experimentally infected mice. It was also active against Artemia salina, but inactive against the fungus Cladosporium sphaerospermum and the snail Biomphalaria glabrata.