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1.
J Ethnopharmacol ; 265: 113248, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32805356

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Verbesina macrophylla (Cass.) S.F.Blake is a medicinal plant from South America, popularly known as "asa de peixe", "asa de peixe branco", "cambará branco" or "cambará guaçu", being used by traditional communities for its healing powers in the form of teas, infusions, liqueurs and extracts, for the treatment of bacterial and fungal infections of the urinary and respiratory tracts, such as kidney problems, bronchitis, inflammation and fever. However, none of the ethnopharmacological properties has been scientifically evaluated. AIM OF THE STUDY: Based on the ethnopharmacological use of the species, this study investigated the chemical composition, and for the first time acute toxicity, hemolytic, antimicrobial, anti-inflammatory and antipyretic activities of the essential oil from leaves of V. macrophylla. MATERIAL AND METHODS: The essential oil was obtained from the leaves by hydrodistillation (HD), being characterized by gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography coupled to flame ionization detection (GC-FID). The antimicrobial activity was evaluated by the broth microdilution technique in bacteria and fungi that cause infections of the respiratory and urinary tract, and toxicological safety regarding hemolytic activity on human red blood cells (hRBCs), and acute toxicity in mice. The anti-inflammatory activity was evaluated by the model carrageenan-induced peritonitis with quantification of the levels of TNF-α and IL-1ß in the intraperitoneal fluid, and ear edema induced by croton oil. The antipyretic activity evaluated in mice with pyrexia induced by yeast. RESULTS: The extraction of essential oil by hydrodistillation (HD) showed a yield of 0.33 ±â€¯0.04%, with its composition constituted mainly by sesquiterpenes of hydrocarbons (94.00%). The essential oil demonstrated antibacterial and antifungal activity, with a low rate of hemolysis in human red blood cells (hRBCs) and no clinical signs of toxicity were observed in animals after acute treatment, which suggested that the LD50 is greater than 5000 mg/kg; p.o. The essential oil demonstrated anti-inflammatory activity reducing levels of pro-inflammatory cytokines TNF-α (38.83%, 72.42% and 73.52%) and IL-1ß (37.70%, 75.92% and 87.71%), and ear edema by 49.53%, 85.04% and 94.39% at concentrations of 4, 40 and 400 mg/kg, respectively. The antipyretic activity presented by the essential oil is statistically similar to dipyrone. CONCLUSION: The set of results obtained, validates the main activities attributed to the traditional use of Verbesina macrophylla (Cass.) S.F.Blake. These data add industrial value to the species, considering that the antimicrobial, anti-inflammatory and antipyretic activities present results similar to the drugs already used also presenting safety. The results suggest that essential oil from V. macrophylla may be used by industry for the development of drugs with natural antimicrobial, anti-inflammatory and antipyretic effect.

2.
J Chem Ecol ; 46(10): 1010-1015, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32984924

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.

3.
Plant Biol (Stuttg) ; 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32757308

RESUMO

Several monoecious species of palms developed complex strategies to promote cross-pollination including the production of large quantities of floral resources and the emission of scent that are attractive to pollinators. Syagrus coronata constitutes an interesting model with which to understand the evolution of plant reproductive strategies in a monoecious species adapted to seasonally dry forests. We monitored blooming phenology over one year, during which we also collected and identified floral visitors and putative pollinators. We identified potential floral visitor attractants by characterizing the scent composition of inflorescences, as well as of peduncular bracts, during both male and female phases, and the potential for floral thermogenesis. Syagrus coronata produces floral resources throughout the year. Its inflorescences are predominantly visited by a diverse assortment of small-sized beetles, whose richness and abundance vary throughout the different phases of anthesis. We did not find evidence of floral thermogenesis. A total of 23 volatile compounds were identified in the scent emitted by the inflorescences, which did not differ between male and female phases; whereas the scent of the peduncular bracts was composed of only 4-methyl guaiacol, which was absent in inflorescences. The composition of floral scent chemistry indicates that palm has evolved strategies to be predominantly pollinated by small-sized weevils. Our study provides rare evidence of a non-floral scent emitting structure involved in pollinator attraction, only the second case specifically in palms. The peculiarities of the reproductive strategy of S. coronata might play an important role in the maintenance of pollination services and pollen dispersion.

4.
J Chem Ecol ; 45(2): 204-213, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30229355

RESUMO

Nocturnal flowering plants often release strong scents to attract their pollinators. Among night active flower visitors are cyclocephaline scarab beetles, which have been demonstrated to respond to uncommon volatile organic compounds released in high amounts by their host plants. In Araceae, the molecular structure of several such compounds is yet to be unveiled. We investigated headspace floral scent samples of Philodendron squamiferum, Thaumatophyllum mello-baretoanum, and Xanthosoma hylaeae by a variety of approaches, leading to the identification of novel compounds. Dehydrojasmone, (Z)-4-methylene-5-(pent-2-en-1-yl)cyclopent-2-en-1-one (1), (Z)-3-methylene-2-(pent-2-en-1-yl)cyclopentyl acetate (isojasmyl acetate, 3), and (E)-4,8-dimethylnona-1,3,7-trien-5-yl acetate (4) had not been previously reported, while full analytical data of the recently described (Z)-3-methylene-2-(pent-2-en-1-yl)cyclopentan-1-ol (isojasmol, 2) are presented here. All these compounds are derived from more common precursors, (Z)-jasmone and (E)-4,8-dimethyl-1,3,7-nonatriene, likely through biosynthetic "post-processing".


Assuntos
Araceae/química , Besouros/fisiologia , Compostos Orgânicos Voláteis/química , Animais , Araceae/metabolismo , Ciclopentanos/química , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Oxilipinas/química , Polinização/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia
5.
J Chem Ecol ; 45(2): 214-215, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30334116

RESUMO

The original version of this article unfortunately contained a mistake. The description of subheadings of Figs. 4c and d have to be interchanged.

6.
Biomed Pharmacother ; 96: 1055-1064, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29217159

RESUMO

Essential/volatile oils (EOs) from plants used in the traditional medicine are known as a rich source of chemically diverse compounds with relevant biological activities. In this work we analysed the chemical composition and the in vitro effects of EOs from leaves of Eugenia brejoensis (EBEO), Hyptis pectinata (HPEO), Hypenia salzmannii (HSEO), Lippia macrophylla (LMEO) and seeds of Syagrus coronata (SCEO) on Trypanosoma cruzi, the etiological agent of Chagas disease. The EOs were extracted through hydrodistillation and its chemical composition analysed by GC/MS. The trypanocidal activity against epi- and trypomastigotes was evaluated by optical microscopy and the cytotoxicity to mammalian cells by MTT. The effects of EOs on parasite infection in macrophages were estimated by determining the survival index and the percentage of infection inhibition. The cytotoxicity against mammalian cells was compared to those of parasite by determining the Selectivity Index (SI). Overall, 114 compounds were identified: The main constituents of EOS were: δ-cadinene (15.88%), trans-caryophyllene (9.77%) e α-Muurolol (9.42%) for EBEO; trans-caryophyllene (15.24%), bicyclogermacrene (7.33%) e cis-calamenene (7.15%) for HFEO; trans-caryophyllene (30.91%), caryophyllene oxide (13.19%) and spathulenol (5.68%) for HPEO; Xanthoxylin (17.20%) trans-caryophyllene (14.34%) and methyl-eugenol (5.60%) for HSEO; Thymol (49.81%), carvacrol (31.6%) and σ-cimene (10.27%) for LMEO and octanoic acid (38.83%) dodecanoic acid (38.45%) and decanoic acid (20.51%) for SCEO. All the tested oils showed an inhibitory effect on the growth and survival of all forms of T. cruzi and moderate cytotoxicity towards the mammalian cells (100 < CC50 < 500 µg/mL). The EO of E. brejoensis was the most effective against the parasite presenting higher Selectivity Index for trypo- (SI = 14.45) and amastigote forms (SI = 20.11). Except for SCEO, which was the most cytotoxic for both parasite and mammalian cells, all the oils demonstrated to be more selective for the parasite than the reference drug benznidazole. Taken together our results point the essential oils from Caatinga plants, especially Eugenia brejoensis, as promissory agents for the development of new drugs against Chagas disease.


Assuntos
Óleos Voláteis/química , Óleos Voláteis/farmacologia , Plantas Medicinais , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Brasil , Células Cultivadas , Eugenia , Lippia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óleos Voláteis/isolamento & purificação , Folhas de Planta , Óleos Vegetais/química , Óleos Vegetais/isolamento & purificação , Óleos Vegetais/farmacologia , Sementes , Tripanossomicidas/isolamento & purificação , Trypanosoma cruzi/fisiologia
7.
Biomed Pharmacother ; 94: 865-872, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28810516

RESUMO

Alpinia purpurata is an ornamental crop known as a source of bioactive molecules. This is the first study to report isolation of a lectin (carbohydrate-binding protein) from A. purpurata inflorescences (ApuL). The immunomodulatory potential of ApuL was evaluated by investigating its effects on the production of cytokines and release of nitric oxide by human peripheral blood mononuclear cells (PBMCs). In addition, the differentiation and activation of lymphocytes treated with ApuL was evaluated by immunophenotyping assays. ApuL is an acidic and oligomeric protein with native molecular mass of 34kDa. The hemagglutinating activity (HA) of ApuL was inhibited by the glycoproteins fetuin and ovalbumin, was resistant to heating at 100°C and stimulated in the presence of calcium and magnesium ions. ApuL showed highest HA at pH 7.5 but failed to agglutinate erythrocytes at pH 8.0 and 9.0. ApuL induced the release of cytokines belonging to Th1 (IFN-γ, TNF-α, and IL-6) and Th17 (IL-17A) profiles as well as of nitric oxide, stimulating a pro-inflammatory environment. Moreover, ApuL also stimulated the production of IL-10, an anti-inflammatory cytokine with regulatory role. Incubation with lectin resulted in differentiation and activation of both T CD8+ and CD4+ subsets of lymphocytes, as evident from the expression of the CD28 costimulatory molecule. In conclusion, A. purpurata inflorescence is a source of an immunomodulatory lectin with potential immunoregulatory application, thereby adding biotechnological value to this ornamental crop.


Assuntos
Alpinia/química , Citocinas/imunologia , Óxido Nítrico/metabolismo , Lectinas de Plantas/farmacologia , Citocinas/efeitos dos fármacos , Fetuínas/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Imunofenotipagem , Inflorescência , Leucócitos Mononucleares/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Ovalbumina/farmacologia , Lectinas de Plantas/isolamento & purificação , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Fator de Necrose Tumoral alfa/imunologia
8.
Parasitol Res ; 113(2): 727-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24271154

RESUMO

Moringa oleifera flower extract, with trypsin inhibitor activity, is a larvicidal agent on Aedes aegypti. This work reports the isolation of trypsin inhibitor (M. oleifera flower trypsin inhibitor (MoFTI)) and its effect on A. aegypti egg hatching, viability of newly hatched larvae, survival of pupae, and growth of inhabitant bacteria from midgut of fourth-instar larvae (L4). MoFTI (K i, 2.4 µM), isolated by affinity chromatography on trypsin-agarose column, was an 18.2 kDa polypeptide on sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Flower extract (at concentrations of 8.5-17.0 mg/mL) reduced egg hatchability while MoFTI (0.05-0.5 mg/mL) did not affect the hatching rate. Mortality of newly hatched larvae ranged from 3.5 to 19.1 % in the presence of the extract (4.0-17.0 mg/mL) and was also promoted by MoFTI (LC50, 0.3 mg/mL). After 72 h, larvae incubated with extract at 13.0 and 17.0 mg/mL were at stages L2 and L1, respectively, while in control they reached L3 instar. In the presence of MoFTI, at all concentrations tested, the larvae did not pass the first instar. Flower extract and MoFTI did not interfere on pupae survival. The extract and MoFTI inhibited the growth of L4 gut bacteria (minimum inhibitory concentrations of 3.47 and 0.031 mg/mL, respectively) but only the inhibitor showed bactericide effect (minimum bactericidal concentration of 1.0 mg/mL). The findings reported herein indicate that MoFTI constitutes a larvicidal principle from M. oleifera flowers against A. aegypti newly hatched larvae and is an antibacterial agent active against the microbiota from L4 gut.


Assuntos
Aedes/crescimento & desenvolvimento , Aedes/microbiologia , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Inseticidas/farmacologia , Moringa oleifera/química , Inibidores da Tripsina/farmacologia , Aedes/efeitos dos fármacos , Animais , Antibacterianos/isolamento & purificação , Sistema Digestório/microbiologia , Flores/química , Inseticidas/análise , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/microbiologia , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Tripsina/metabolismo , Inibidores da Tripsina/isolamento & purificação
9.
J Chem Ecol ; 38(9): 1072-80, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22918609

RESUMO

Cyclocephaline scarabs are specialised scent-driven pollinators, implicated with the reproductive success of several Neotropical plant taxa. Night-blooming flowers pollinated by these beetles are thermogenic and release intense fragrances synchronized to pollinator activity. However, data on floral scent composition within such mutualistic interactions are scarce, and the identity of behaviorally active compounds involved is largely unknown. We performed GC-MS analyses of floral scents of four species of Annona (magnoliids, Annonaceae) and Caladium bicolor (monocots, Araceae), and demonstrated the chemical basis for the attraction of their effective pollinators. 4-Methyl-5-vinylthiazole, a nitrogen and sulphur-containing heterocyclic compound previously unreported in flowers, was found as a prominent constituent in all studied species. Field biotests confirmed that it is highly attractive to both male and female beetles of three species of the genus Cyclocephala, pollinators of the studied plant taxa. The origin of 4-methyl-5-vinylthiazole in plants might be associated with the metabolism of thiamine (vitamin B1), and we hypothesize that the presence of this compound in unrelated lineages of angiosperms is either linked to selective expression of a plesiomorphic biosynthetic pathway or to parallel evolution.


Assuntos
Annonaceae/química , Araceae/química , Besouros/efeitos dos fármacos , Flores/química , Percepção Olfatória/efeitos dos fármacos , Polinização , Tiazóis/farmacologia , Compostos de Vinila/farmacologia , Animais , Annonaceae/fisiologia , Araceae/fisiologia , Bioensaio , Besouros/fisiologia , Sinais (Psicologia) , Feminino , Flores/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Percepção Olfatória/fisiologia , Feromônios/análise , Feromônios/farmacologia , Polinização/efeitos dos fármacos , Tiazóis/análise , Compostos de Vinila/análise
10.
Parasitol Res ; 110(2): 609-16, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21735148

RESUMO

Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essential, since a vaccine for dengue has not as yet been made available. This work reports on the larvicidal activity of Myracrodruon urundeuva leaf lectin (MuLL) against A. aegypti fourth-stage larvae (L(4)). Also, the resistance of MuLL to digestion by L(4) gut proteases and the effects of MuLL on protease, trypsin-like and α-amylase activities from L(4) gut were evaluated to determine if lectin remains active in A. aegypti gut and if insect enzyme activities can be modulated by MuLL. MuLL promoted mortality of L(4) with LC(50) of 0.202 mg/ml. Haemagglutinating activity of MuLL was detected even after incubation for 96 h with L(4) gut preparation containing protease activity. MuLL affected the activity of gut enzymes, inhibiting protease and trypsin activities and stimulating α-amylase activity. The results suggest that MuLL may become a new biodegradable larvicidal agent for dengue control. Larvicidal activity of MuLL may be linked to its resistance to proteolysis by larval enzymes and interference in the activity of digestive larval enzymes.


Assuntos
Aedes/efeitos dos fármacos , Anacardiaceae/química , Inibidores Enzimáticos/farmacologia , Inseticidas/farmacologia , Lectinas/farmacologia , Extratos Vegetais/farmacologia , Aedes/enzimologia , Aedes/fisiologia , Animais , Inibidores Enzimáticos/isolamento & purificação , Enzimas/metabolismo , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Larva/enzimologia , Larva/fisiologia , Lectinas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Análise de Sobrevida
11.
Chem Pharm Bull (Tokyo) ; 57(8): 819-25, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19652406

RESUMO

The synthesis of 3-(3-aryl-1,2,4-oxadiazol-5-yl)propionic acids from arylamidoximes and succinic anhydride under focused microwave irradiation conditions is described. The new synthetic method furnished the desired products in 2-3 min and good yields. Furthermore, the previously complicated purification procedure has been simplified in a manner which is quick, eco-friendly and cost-effective. Larvicidal bioassay and fungal growth inhibitory tests were performed using several 3-(3-aryl-1,2,4-oxadiazol-5-yl)propionic acids. These acids presented strong larvicidal activity against L4 larvae of Aedes aegypti. The results suggest that larvicidal activity might be correlated with the presence of electron-withdrawing substituents in the para position of the phenyl ring except the fluorine atom. The alterations observed in the larvae spiracular valves of the siphon and anal papillae by 1,2,4-oxadiazoles in the larvicidal bioassay are responsible for larvae's death. Furthermore, all acids inhibited the fungal growth of five different types of fungi, viz., Fusarium solani, F. oxysporum, F. moniliforme, F. decemcellulare and F. lateritium in a preliminary evaluation. Both of these activities are being disclosed for the first time for 1,2,4-oxadiazole-5-yl ring linked at C-3 of propionic acid.


Assuntos
Antifúngicos/síntese química , Fusarium/efeitos dos fármacos , Inseticidas/síntese química , Micro-Ondas , Oxidiazóis/farmacologia , Propionatos/farmacologia , Aedes/efeitos dos fármacos , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Fusarium/crescimento & desenvolvimento , Inseticidas/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oxidiazóis/síntese química , Oxidiazóis/química , Propionatos/síntese química , Propionatos/química , Estereoisomerismo , Relação Estrutura-Atividade
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