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1.
Pestic Biochem Physiol ; 158: 156-165, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378352

RESUMO

Culex pipiens is a main vector for Bancroftian filariasis, Rift Valley Fever and diseases caused by other viruses, leaving several peoples with disabilities. In recent years, plant derived compounds have received much attention as potential alternatives to synthetic chemicals due to their low toxicity to mammals and environmental persistence. Twenty-one monoterpenes from different chemical groups (hydrocarbons and oxygenated products) were evaluated against Culex pipiens larvae. In addition, in vivo biochemical studies including effects on acetylcholine esterase (AChE), acid and alkaline phosphatases (ACP and ALP), total adenosine triphosphatase (ATPase) and gamma-aminobutyric acid transaminase (GABA-T) were investigated. Furthermore, in silico studies including pharmacophore elucidation, ADMET analysis and molecular docking of these compounds were performed. Among all tested monoterpenes, hydrocarbons [p-cymene, (R)-(+)-limonene and (+)-α-pinene], acetates (cinnamyl acetate, citronellyl acetate, eugenyl acetate and terpinyl acetate), alcohols [(±)-ß-citronellol and terpineol], aldehydes [citral and (1R)-(-)-myrtenal] and ketone [(R)-(+)-pulegone] exhibited the highest larval toxicity with LC50 = 14.88, 27.97, 26.13, 2.62, 3.81, 2.74, 21.65, 1.64, 21.70, 21.76, 1.68 and 1.90 mg/L after 48 h of exposure, respectively. The compounds proved a significant inhibition of all tested enzymes except total ATPase. The biochemical and molecular docking studies proved that AChE and GABA-T were the main targets for the tested monoterpenes.


Assuntos
Culex/virologia , Inseticidas/farmacologia , Monoterpenos/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Culex/patogenicidade , Filariose Linfática/transmissão , Ativação Enzimática/efeitos dos fármacos , Esterases/metabolismo , Simulação de Acoplamento Molecular , Transaminases/metabolismo
2.
Pestic Biochem Physiol ; 158: 185-200, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378356

RESUMO

The present work describes the antimicrobial action of 25 monoterpenes (six hydrocarbons, five ketones, two aldehydes, six alcohols and six acetate analogues) against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus and antifungal activity against Aspergillus flavus. The antibacterial activity was evaluated by broth microdilution technique as a minimum inhibitory concentration (MIC) and the antifungal activity was performed by mycelia radial growth technique as the effective concentration causing 50% inhibition of the mycelial growth (EC50). The results showed that thymol and α-terpineol were the most potent against E. coli (MIC = 45 and 55 mg/L, respectively) and S. aureus (MIC = 135 and 225 mg/L, respectively). The results also showed that thymol displayed the maximum antifungal action against A. flavus with EC50 20 mg/L. Furthermore, the antioxidant activity was determined using N,N-dimethyl-1,4-phenylenediamine (DMPD) and the results showed that geraniol were the most potent compound (IC50 = 19 mg/L). Molecular docking studies indicated that the compounds displayed different binding interactions with the amino acid residues at the catalytic sites of N5-carboxyaminoimidazole synthetase and oxysterol binding protein Osh4 enzymes. Non-covalent interactions including van der Waals, hydrogen bonding as well as hydrophobic were observed between the compounds and the enzymes. A significant relationship was found between the docking score and the biological activity of the tested monoterpenes compared to the ceftriaxone and carbendazim as standard bactericide and fungicide, respectively. In silico ADMET properties were also performed and displayed potential for the development of promising antimicrobial agents. For these reasons, these compounds may be considered as potential ecofriendly alternatives in food preservation to delay or prevent the microbial infection and prolong the shelf life of food products.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Monoterpenos/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Cicloexenos/química , Cicloexenos/farmacologia , Escherichia coli/efeitos dos fármacos , Hidrocarbonetos/química , Hidrocarbonetos/farmacologia , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos
3.
J Chem Ecol ; 45(8): 715-724, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31385154

RESUMO

Plants emit a specific blend of volatiles in response to herbivory and these volatiles, which often attract predators and parasitoids function as an indirect plant defense. The impact of plant volatiles in shaping herbivore defenses is unclear. Here, we report that specific plant volatiles induce immune responses in the polyphagous herbivore, Spodoptera litura. We characterized the hemocyte profile and established their functional significance with respect to ontogeny and exposure to specific plant volatiles. Fifth instar larvae showed the highest number and hemocytes diversity. We characterized seven different types of hemocytes, of which granulocytes performed phagocytosis, oenocytoids showed melanization activity, and plasmatocytes along with granulocytes and oenocytoids were found to be involved in encapsulation. Among the six volatiles tested, exposure to (E)-ß-ocimene caused the highest increase in total hemocytes number (THC) followed by linalool and (Z)-3-hexenyl acetate exposure. Although THC did not differ between these three volatile treatments, circulating hemocytes diversity varied significantly. (E)-ß-ocimene exposure showed higher number of plasmatocytes and phenol oxidase activity. The interaction of the parasitic wasp Bracon brevicornis with (E)-ß-ocimene exposed larvae was poor in terms of delayed paralysis and lower egg deposition. In choice assays, the wasp showed clear preference towards control larvae indicating (E)-ß-ocimene treatment renders the host unattractive. Hemocyte profiles post-parasitoid exposure and (E)-ß-ocimene treatment were similar indicating cue-based priming. When challenged with Bacillus thuringiensis, linalool exposure resulted in the highest survival as compared to other volatiles. Our results show that specific HIPVs can modulate cellular immunity of S. litura, revealing a new role for HIPVs in tri-trophic interactions.


Assuntos
Compostos Orgânicos Voláteis/farmacologia , Vespas/fisiologia , Alcenos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Hemócitos/citologia , Hemócitos/efeitos dos fármacos , Hemócitos/metabolismo , Herbivoria , Interações Hospedeiro-Parasita , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/metabolismo , Larva/fisiologia , Monofenol Mono-Oxigenase/metabolismo , Monoterpenos/farmacologia , Oviposição/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Plantas/química , Plantas/metabolismo , Plantas/parasitologia , Compostos Orgânicos Voláteis/química , Vespas/imunologia
4.
J Chem Ecol ; 45(8): 657-666, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31407199

RESUMO

The box tree moth, Cydalima perspectalis, is an invasive pest in Europe causing damage on Buxus species. In this study, we aimed to develop a "bisexual" lure to attract both female and male moths. Based on a previous screening bioassay we tested methyl salicylate, phenylacetaldehyde and eugenol as potential attractants in different combinations. The trapping results showed that both binary and ternary blends attracted male and female moths. Catches with these blends were comparable to catches with the synthetic pheromone. Subsequently we carried out single sensillum recordings, which proved the peripheral detection of the above-mentioned compounds on male and female antennae. To identify synergistic flower volatiles, which can be also attractive and can increase the trap capture, we collected flower headspace volatiles from 12 different flowering plant species. Several components of the floral scents evoked good responses from antennae of both females and males in gas chromatography-electroantennographic detection. The most active components were tentatively identified by gas chromatography coupled mass spectrometry as benzaldehyde, cis-ß-ocimene, (±)-linalool and phenethyl alcohol. These selected compounds in combination did not increase significantly the trap capture compared to the methyl salicylate- phenyacetaldehyde blend. Based on these results we discovered the first attractive blend, which was able to attract both adult male and female C. perspectalis in field conditions. These results will yield a good basis for the optimization and development of a practically usable bisexual lure against this invasive pest.


Assuntos
Comportamento Animal/efeitos dos fármacos , Mariposas/fisiologia , Feromônios/farmacologia , Animais , Eugenol/química , Eugenol/farmacologia , Feminino , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Controle de Insetos , Masculino , Monoterpenos/química , Monoterpenos/farmacologia , Feromônios/análise , Robinia/química , Robinia/metabolismo , Rosa/química , Rosa/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia
5.
Chem Pharm Bull (Tokyo) ; 67(7): 675-689, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257323

RESUMO

An Orobanchaceae plant Cistanche tubulosa (SCHENK) WIGHT (Kanka-nikujuyou in Japanese), which is one of the authorized plant resources as Cistanches Herba in both Japanese and Chinese Pharmacopoeias, is a perennial parasitic plant growing on roots of sand-fixing plants. The stems of C. tubulosa have traditionally been used for treatment of impotence, sterility, lumbago, and body weakness as well as a promoting agent of blood circulation. In recent years, Cistanches Herba has also been widely used as a health food supplement in Japan, China, and Southeast Asian countries. Here we review our recent studies on chemical constituents from the stems of C. tubulosa as well as their bioactivities such as vasorelaxtant, hepatoprotective, and glucose tolerance improving effects.


Assuntos
Produtos Biológicos/química , Cistanche/química , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Cistanche/metabolismo , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Monoterpenos/química , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Caules de Planta/química , Caules de Planta/metabolismo , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Vasodilatadores/química , Vasodilatadores/isolamento & purificação , Vasodilatadores/farmacologia
6.
Cell Physiol Biochem ; 53(2): 285-300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31334617

RESUMO

BACKGROUND/AIMS: Although naturally-derived antifungals have been investigated for their ability to inactivate Candida albicans, which is a major cause of candidiasis, they have shown a less than 3 log reduction in C. albicans or required treatment times of longer than 3 h. Thus, the naturally-derived antifungals used in previous studies could not substantially eradicate C. albicans within a short period of time. METHODS: To improve the fungicidal effects of naturallyderived antifungals against C. albicans within short time periods, we developed composites showing antifungal synergism using caprylic acid (CA), carvacrol (CAR) and thymol (THM) for 1-10 min at 22/37°C. Using flow cytometry, we examined the mode of action for the synergism of these compounds on membrane integrity and efflux pump activity. RESULTS: Whereas the maximum reduction by individual treatments was 0.6 log CFU/ml, CA + CAR/THM (all 1.5 mM) eliminated all pathogens (> 6.8 log reduction) after 1 min at 37°C and after 10 min at 22°C. The flow cytometry results showed that exposure to CA damaged the membranes in 15.7-36.5% of cells and inhibited efflux pumps in 15.4-31.3% of cells. Treatments with CAR/THM slightly affected cell membranes (in 1.8-6.9% of cells) but damaged efflux pumps in 14.4-29.6% of cells. However, the combined treatments clearly disrupted membranes (> 83.1% of cells) and pumps (> 95.0% of cells). The mechanism of this synergism may involve membrane damage by CA, which facilitates the entry of antifungals into the cytoplasm, and the inhibition of efflux pumps by CA, CAR or THM, causing their accumulation within cells and, leading to cell death. CONCLUSION: Antifungal composites (CA + CAR/THM) showing synergism (i.e., an additional 6 log reduction) within minutes at room/body temperature can be used to treat candidiasis and improve the microbiological safety of facilities contaminated with fungi as a novel alternative to synthetic antifungals.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Caprilatos/farmacologia , Proteínas Fúngicas/metabolismo , Monoterpenos/farmacologia , Timol/farmacologia , Candida albicans/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Sinergismo Farmacológico , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Temperatura Ambiente
7.
J Agric Food Chem ; 67(33): 9265-9276, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31361479

RESUMO

Fungal infections significantly alter the emissions of volatile organic compounds (VOCs) by plants, but the mechanisms for VOCs affecting fungal infections of plants remain largely unknown. Here, we found that infection by Botrytis cinerea upregulated linalool production by strawberries and fumigation with linalool was able to inhibit the infection of fruits by the fungus. Linalool treatment downregulated the expression of rate-limiting enzymes in the ergosterol biosynthesis pathway, and this reduced the ergosterol content in the fungi cell membrane and impaired membrane integrity. Linalool treatment also caused damage to mitochondrial membranes by collapsing mitochondrial membrane potential and also downregulated genes involved in adenosine triphosphate (ATP) production, resulting in a significant decrease in the ATP content. Linalool treatment increased the levels of reactive oxygen species (ROS), in response to which the treated fungal cells produced more of the ROS scavenger pyruvate. RNA-Seq and proteomic analysis data showed that linalool treatment slowed the rates of transcription and translation.


Assuntos
Botrytis/efeitos dos fármacos , Fragaria/metabolismo , Frutas/microbiologia , Monoterpenos/metabolismo , Doenças das Plantas/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Trifosfato de Adenosina/metabolismo , Botrytis/crescimento & desenvolvimento , Fragaria/química , Fragaria/microbiologia , Frutas/química , Frutas/metabolismo , Interações Hospedeiro-Patógeno , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Monoterpenos/farmacologia , Doenças das Plantas/prevenção & controle , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Compostos Orgânicos Voláteis/farmacologia
8.
Phytochemistry ; 164: 236-242, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31185420

RESUMO

Mangiterpenes A-C and 2',3'-seco-manginoid C, four undescribed sesquiterpene/monoterpene-shikimate-conjugated meroterpenoids with spiro ring systems, were isolated from Guignardia mangiferae. The structures and absolute configurations of these compounds were established by comprehensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Mangiterpenes A-C represent the first examples of sesquiterpene-shikimate-conjugated spirocyclic meroterpenoids, and 2',3'-seco-manginoid C features an unexpected 2',3'-seco-manginoids skeleton. Mangiterpene C strongly inhibited the production of NO inducted by LPS, with an IC50 value of 5.97 µM. It showed an anti-inflammatory effect by means of blocking in the NF-κB signaling pathway and decreasing the expression of inflammatory mediators.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Monoterpenos/farmacologia , Ácido Chiquímico/farmacologia , Compostos de Espiro/farmacologia , Terpenos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Relação Dose-Resposta a Droga , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Monoterpenos/química , Monoterpenos/isolamento & purificação , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Células RAW 264.7 , Ácido Chiquímico/química , Ácido Chiquímico/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Compostos de Espiro/química , Compostos de Espiro/isolamento & purificação , Relação Estrutura-Atividade , Terpenos/química , Terpenos/isolamento & purificação
9.
Planta Med ; 85(11-12): 941-946, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31163460

RESUMO

Targeted isolation based on a combination of NMR and HPLC-PDA-MS of a dichloromethane extract of Thymus vulgaris Varico 3 aerial parts afforded one new p-cymene dimer, 6,3',4'-trihydroxy-5,5'-diisopropyl-2,2'-dimethylbiphenyl (1: ), together with two known p-cymene derivatives (2: and 3: ), as well as five known compounds, namely, thymol (4: ), oleanolic acid (5: ), ursolic acid (6: ), cirsimaritin (7: ), and xanthomicrol (8: ). The structural elucidation of all compounds was performed by spectroscopic analyses, including 1D and 2D NMR, and HRESIMS experiments. The biphenyls were assayed for their inhibitory activity on tyrosinase. Compounds 2: and 3: showed negligible activity on tyrosinase, while compound 1: effectively inhibited the enzyme with 35% (± 0.3) inhibitory activity, higher than the inhibition of the reference compound kojic acid (18.6 ± 0.02).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monoterpenos/isolamento & purificação , Extratos Vegetais/química , Thymus (Planta)/química , Flavonas/farmacologia , Monoterpenos/farmacologia , Ácido Oleanólico/farmacologia , Timol/farmacologia , Triterpenos/farmacologia
10.
Planta Med ; 85(9-10): 745-754, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31167299

RESUMO

ELOM-080, also known as Myrtol, represents a distillate of a mixture of 4 rectified essential oils: eucalyptus oil, sweet orange oil, myrtle oil, and lemon oil. ELOM-080 is an approved herbal medicinal product for the secretolytic therapy and facilitation of expectoration in acute and chronic bronchitis and for the secretolytic therapy of sinusitis. Its clinical efficacy has been reported by several randomized control trials. Interestingly, in the recent past, a considerable number of clinical studies on the use of ELOM-080 as add-on treatment of different respiratory tract diseases has been conducted and published in China. As these publications were only available in Chinese, the international attention in the literature was limited. Based on the translation of these studies into English, this review aims to provide a brief overview of the studies' major results, which contribute to the knowledge on the efficacy of ELOM-080 in the treatment of respiratory tract diseases: ELOM-080 was shown to be of great value as add-on treatment not only for the well-established indications bronchitis and sinusitis, but also for pharyngitis, asthma, chronic obstructive pulmonary disease, and, most importantly, otitis media. Besides this clinical evidence, this review also summarizes the great progress in deciphering the mode of action of ELOM-080 that has been made by Chinese publications.


Assuntos
Monoterpenos/uso terapêutico , Doenças Respiratórias/tratamento farmacológico , Asma/tratamento farmacológico , Bronquite/tratamento farmacológico , China , Combinação de Medicamentos , Humanos , Monoterpenos/farmacologia , Otite Média/tratamento farmacológico , Faringite/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Sinusite/tratamento farmacológico
11.
Eur J Med Chem ; 178: 515-529, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207463

RESUMO

Carvacrol (CAR), a natural monoterpene particularly abundant in plants belonging to the Lamiaceae family, has recently attracted much attention for its many biological properties (antioxidant, anti-inflammatory, neuroprotective, antitumour, antibacterial, and several others). However, CAR has poor chemical-physical properties (low water solubility and high volatility), which hamper its potential pharmacological uses. In this paper, the synthesis and antimicrobial evaluation of 23 carvacrol derivatives (WSCP1-23) against a panel of selected gram-positive and gram-negative bacteria are reported. Using the prodrug approach, CAR hydrophilic (WSCP1-17) and lipophilic prodrugs (WSCP18-23) were prepared. Notably, CAR water solubility was increased by using polar neutral groups (such as natural amino acids) with the aim of improving oral drug delivery. On the other hand, CAR lipophilic prodrugs, obtained by prenylation of CAR hydroxyl group, were designed to promote membrane permeation and oral absorption. Our results revealed that WSCP1-3, showing the highest water solubility (>1700-fold compared to that of CAR), possessed good antibacterial activity against gram-negative bacteria with MIC values comparable to those of CAR and antifungal properties against different species of Candida. WSCP18-19 were the most promising prodrugs, showing good antibacterial profiles against gram-positive bacteria by interfering with the biofilm formation of Staphylococcus aureus and Staphylococcus epidermidis. Moreover, WSCP18-19 resulted more stable in simulated fluids and human plasma than WSCP1-3. Toxicity studies performed on human erythrocytes and HaCaT cells revealed that all WSCPs were not toxic at the tested concentrations.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Monoterpenos/farmacologia , Pró-Fármacos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Candida/efeitos dos fármacos , Relação Dose-Resposta a Droga , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monoterpenos/síntese química , Monoterpenos/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Solubilidade , Relação Estrutura-Atividade
12.
Life Sci ; 232: 116608, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254583

RESUMO

Preventing vascular damage is considered an effective strategy in patients who suffer from chronic obstructive pulmonary disease (COPD) with hypertension. Here, we investigated vascular damage in COPD-like and hypertensive rats, which demonstrated the presence of the three related factors of COPD with hypertension. These include elevated systolic blood pressure (SBP), serum malondialdehyde (MDA) and serum lactate dehydrogenase (LDH), which are positively correlated with vascular damage in patients. In addition to increases in these three related factors, COPD-like and hypertensive rats exhibited increased levels of pro-inflammatory mediators, such as tumor necrosis factor-α, interleukin-6, and matrix metallopeptidase-9 in bronchoalveolar lavage fluid, and enlargement of alveolar airspaces, recapitulating clinical findings in previous studies of patients. Moreover, the appearance of these related factors was prevented by linalyl acetate. Our results provide novel insight into the potential of LA to prevent vascular damage and elevated SBP, serum MDA and serum LDH in COPD with hypertension, and could lead to an alternative strategy for preventing vascular damage for patients who suffered from COPD with hypertension in a clinical setting.


Assuntos
Hipertensão/tratamento farmacológico , Monoterpenos/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Animais , Pressão Sanguínea/fisiologia , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Hipertensão/patologia , Hipertensão/fisiopatologia , L-Lactato Desidrogenase/análise , L-Lactato Desidrogenase/sangue , Pulmão/patologia , Masculino , Malondialdeído/análise , Malondialdeído/sangue , Doença Pulmonar Obstrutiva Crônica/patologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Ratos , Ratos Sprague-Dawley
13.
J Chem Ecol ; 45(5-6): 464-473, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31111291

RESUMO

Different enantiomers of chiral compounds within floral perfumes usually trigger distinct responses in insects; however, this has frequently been neglected in studies investigating semiochemicals in plant-pollinator interactions. Approximately 1000 neotropical plants produce floral perfumes as the only reward for pollinators, i.e. male euglossine bees. The chiral compound carvone epoxide is a key component of the scent bouquet of many perfume-rewarding plants that are pollinated by males of Eulaema. Here, we tested the biological activity of the four carvone epoxide stereoisomers to four Eulaema species occurring in the Atlantic Rainforest of NE-Brazil. We determined the stereochemistry of carvone epoxide in the floral scent of several Catasetum species, tested whether the antennae of bees respond differentially to these stereoisomers and investigated if there is a behavioural preference for any of the stereoisomers. We found that 1) Catasetum species emit only the (-)-trans-stereoisomer of carvone epoxide, 2) for E. atleticana and E. niveofasciata antennal responses to the (-)-trans-carvone epoxide were significantly stronger than those to (-)-cis-carvone epoxide, 3) the strength and pattern of antennal responses to all 4 stereoisomers (separately tested) did not differ among Eulaema species, and 4) there were significant differences in attractiveness of the four stereoisomers to the bees species with the (-)-trans-stereoisomer being particularly attractive. We assume (-)-trans-carvone epoxide to be the dominant isomer in perfume-rewarding plants pollinated by Eulaema. The universal occurrence of carvone epoxide in Catasetum species pollinated by Eulaema, suggests that this compound has evolved in perfume-rewarding as a specific attractant for Eulaema bees as pollinators.


Assuntos
Abelhas/fisiologia , Monoterpenos/química , Animais , Comportamento Animal/efeitos dos fármacos , Cromatografia Gasosa , Compostos de Epóxi/química , Flores/química , Flores/metabolismo , Masculino , Monoterpenos/farmacologia , Orchidaceae/química , Orchidaceae/metabolismo , Estereoisomerismo
14.
J Chem Ecol ; 45(5-6): 455-463, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31140030

RESUMO

The spherical mealybug Nipaecoccus viridis is a pest of several major crops including soybeans, grapes and citrus varieties. Sessile virgin females of N. viridis release two volatiles, 2,2,3,4-tetramethyl-3-cyclopentene-1-methanol (γ-necrodol) and γ-necrodyl isobutyrate, on a circadian rhythm with peak at 17:00 (11 hr of photophase) as determined by automated, sequential solid phase micro extraction with gas chromatography-mass spectrometry analysis. The females increased the released amounts with age by about seven-fold from 5 to 6 d to 10-12 d of age. trans-3,4,5,5-Tetramethyl-2-cyclopentene-1-methanol (trans-α-necrodol) and trans-α-necrodyl acetate, found in essential oil of Spanish lavender, Lavandula luisieri, were rearranged to γ-necrodol and then used to synthesize γ-necrodyl isobutyrate. GC-MS and NMR data confirmed the identifications. In a petri dish bioassay, N. viridis males were significantly attracted to filter paper discs impregnated with γ-necrodyl isobutyrate but not to γ-necrodol or controls. A mixture of the two compounds was not more attractive than γ-necrodyl isobutyrate alone. Similar results were obtained with trapping flying adults, suggesting that the sex pheromone consists only of γ-necrodyl isobutyrate. This compound has not been reported previously in insects. Conversion of α-necrodol in lavender essential oil simplifies the synthesis of the sex pheromone and should allow its use in management of this cosmopolitan invasive pest.


Assuntos
Hemípteros/química , Atrativos Sexuais/química , Animais , Ciclopentanos/química , Ciclopentanos/isolamento & purificação , Ciclopentanos/farmacologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hemípteros/fisiologia , Isomerismo , Espectroscopia de Ressonância Magnética , Masculino , Monoterpenos/química , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Atrativos Sexuais/isolamento & purificação , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Microextração em Fase Sólida
15.
J Chem Ecol ; 45(5-6): 474-489, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31053976

RESUMO

Bark beetles kill apparently vigorous conifers during epidemics by means of pheromone-mediated aggregation. During non-endemic conditions the beetles are limited to use trees with poor defense, like wind-thrown. To find olfactory cues that help beetles to distinguish between trees with strong or weak defense, we collected volatiles from the bark surface of healthy felled or standing Picea abies trees. Furthermore, living trees were treated with methyl jasmonate in order to induce defense responses. Volatiles were analyzed by combined gas chromatography and electroantennographic detection (GC-EAD) on Ips typographus antennae. Compounds eliciting antennal responses were characterized by single sensillum recording for identification of specific olfactory sensory neurons (OSN). Release of monoterpene hydrocarbons decreased, while oxygenated compounds increased, from spring to early summer in felled trees. In both beetle sexes particular strong EAD activity was elicited by trace amounts of terpene alcohols and ketones. 4-Thujanol gave a very strong response and the absolute configuration of the tested natural product was assigned to be (+)-trans-(1R,4S,5S)-thujanol by stereoselective synthesis and enantioselective gas chromatography. One type of OSN responded to all ketones and five other OSN were characterized by the type of compounds that elicited responses. Three new OSN classes were found. Of the eight EAD-active compounds found in methyl jasmonate-treated bark, the known anti-attractant 1,8-cineole was the one most strongly induced. Our data support the hypothesis that highly active oxygenated host volatiles could serve as positive or negative cues for host selection in I. typographus and in other bark beetles.


Assuntos
Besouros/fisiologia , Monoterpenos/química , Estireno/química , Acetatos/farmacologia , Animais , Ciclopentanos/farmacologia , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos/síntese química , Monoterpenos/farmacologia , Oxilipinas/farmacologia , Picea/química , Picea/metabolismo , Casca de Planta/química , Casca de Planta/efeitos dos fármacos , Casca de Planta/metabolismo , Estereoisomerismo , Estireno/farmacologia
16.
Life Sci ; 229: 139-148, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31085246

RESUMO

Citral (CIT) is a monoterpene formed by the geranial and neral stereoisomers. CIT is the major compound of Cymbopogon citratus essential oil, commonly known as "lemongrass", and has demonstrated potential antihyperalgesic, anti-nociceptive and anti-inflammatory effects. However, CIT shows high volatility, low solubility in water and consequent low bioavailability, which limits its use. Therefore, the aim of this study was to evaluate cell viability, anti-hyperalgesic and anti-inflammatory effects of inclusion complexes of CIT on ß-cyclodextrin (ß-CD) and hydroxypropyl-ß-cyclodextrin (HP-ß-CD). Initially, physical mixture (PM) and freeze-dried inclusion (FD) complexes of CIT/ß-CD and CIT/HP-ß-CD were obtained in the molar ratio (1:1). The samples were characterized by DSC, TG/DTG, FT-IR, XRD, SEM and the complexation efficiency were performed by HPLC. Cell viability assay was performed by rezasurin reduction technique in J774 macrophages cell line. The motor activity through rota rod apparatus, mechanical hyperalgesia and pleurisy induced by carrageenan were evaluated in mice. The complexation of CIT was evidenced with ß-CD and HP-ß-CD by the characterization techniques analyzed. The complexation efficiency of CIT/ß-CD and CIT/HP-ß-CD were 78.6% and 71.7%, respectively. The CIT, CIT/ß-CD and CIT/HP-ß-CD showed cell viability in macrophages and did not interfere in the motor activity of mice. Besides that, the samples demonstrated antihyperalgesic and anti-inflammatory activity due to the reduction in total leukocytes and TNF-α levels. However, CIT/ß-CD has better pharmacological effects among the three samples evaluated. Therefore, CIT/ß-CD has potential for the development of products to treat inflammatory and pain reactions.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/farmacologia , Anti-Inflamatórios/farmacologia , Modelos Animais de Doenças , Hiperalgesia/tratamento farmacológico , Inflamação/tratamento farmacológico , Monoterpenos/farmacologia , beta-Ciclodextrinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Carragenina/toxicidade , Quimioterapia Combinada , Hiperalgesia/induzido quimicamente , Hiperalgesia/patologia , Inflamação/induzido quimicamente , Inflamação/patologia , Masculino , Camundongos
17.
Biofouling ; 35(3): 361-375, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31088182

RESUMO

The aim of the present study was to determine the bioactive compounds in four essential oils (EO's) from Origanum heracleoticum, Origanum vulgare, Thymus vulgaris and Thymus serpyllum and to assess their antimicrobial and anti-biofilm activity against Salmonella Enteritidis. Strains were previously characterized depending on the expression of the extracellular matrix components cellulose and curli fimbriae as rdar (red, dry and rough) and bdar morphotype (brown, dry and rough). This study revealed that the EO's and EOC's (carvacrol and thymol) investigated showed inhibition of biofilm formation at sub-minimum inhibitory concentration. Comparing the efficacy of EO's and EOC's in the inhibition of biofilm formation between the strains with different morphotype (rdar and bdar) did not show a statistically significant difference. Results related to the effectiveness of EO's and EOC's (the essential oil components, carvacrol and thymol) on eradication of preformed 48 h old biofilms indicated that biofilm reduction occurred in a dose-dependent manner over time.


Assuntos
Biofilmes/efeitos dos fármacos , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Salmonella enteritidis/efeitos dos fármacos , Timol/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Salmonella enteritidis/fisiologia
18.
Mol Med Rep ; 19(6): 5185-5194, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059080

RESUMO

Sphincter of Oddi dysfunction (SOD) is a benign obstructive disorder predominantly resulting from spasms of the SO. Pharmacological therapies aim to induce SO relaxation; the hypercholesterolemic (HC) rabbit is the only SOD model available for study. In the present study, SO muscle strips, intracellular calcium ion concentrations and the mRNA expression levels of the α1C subunit of the L­type calcium channel in the SO muscle cells of HC rabbits were employed to investigate the effects of paeoniflorin (PF). Alterations in L­type calcium channel α subunit 1C mRNA and protein expression in SO cells with HC following the application of different concentrations of PF were determined by reverse transcription­quantitative polymerase chain reaction and western blotting. The whole cell patch clamp technique was used to observe the effects of different concentrations of paeoniflorin on L­type calcium channel current. The results of the present study demonstrated that PF induced the relaxation of SO muscle strips and reduced the intracellular calcium concentration in the SO muscle cells of HC rabbits. In addition, PF decreased the mRNA expression levels of the α1C subunit of the L­type calcium channel and reduced the L­type calcium channel current in SO cells. These results suggested that the mechanism underlying the relaxation of the SO muscle by PF may be associated with the reduction of calcium ion influx via L­type calcium channels.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Canais de Cálcio Tipo L/metabolismo , Glucosídeos/farmacologia , Hipercolesterolemia/patologia , Monoterpenos/farmacologia , Músculos/efeitos dos fármacos , Esfíncter da Ampola Hepatopancreática/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Colesterol/sangue , Modelos Animais de Doenças , Feminino , Glucosídeos/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/metabolismo , Masculino , Monoterpenos/uso terapêutico , Tono Muscular/efeitos dos fármacos , Músculos/fisiologia , Técnicas de Patch-Clamp , Coelhos
19.
Microbiol Immunol ; 63(6): 213-222, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31106894

RESUMO

Hinokitiol, a component of the essential oil isolated from Cupressaceae, possesses antibacterial and antifungal activities and has been used in oral care products. In this study, the antibacterial activities of hinokitiol toward various oral, nasal and nasopharyngeal pathogenic bacteria, including Streptococcus mutans, Streptococcus sobrinus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Fusobacterium nucleatum, methicillin-resistant and -susceptible Staphylococcus aureus, antibiotic-resistant and -susceptible Streptococcus pneumoniae, and Streptococcus pyogenes were examined. Growth of all these bacterial strains was significantly inhibited by hinokitiol, minimal inhibitory concentrations of hinokitiol against S. mutans, S. sobrinus, P. gingivalis, P. intermedia, A. actinomycetemcomitans, F. nucleatum, methicillin-resistant S. aureus, methicillin-susceptible S. aureus, antibiotic-resistant S. pneumoniae isolates, antibiotic-susceptible S. pneumoniae, and S. pyogenes being 0.3, 1.0, 1.0, 30, 0.5, 50, 50, 30, 0.3-1.0, 0.5, and 0.3 µg/mL, respectively. Additionally, with the exception of P. gingivalis, hinokitiol exerted bactericidal effects against all bacterial strains 1 hr after exposure. Hinokitiol did not display any significant cytotoxicity toward the human gingival epithelial cell line Ca9-22, pharyngeal epithelial cell line Detroit 562, human umbilical vein endothelial cells, or human gingival fibroblasts, with the exception of treatment with 500 µg/mL hinokitiol, which decreased numbers of viable Ca9-22 cells and gingival fibroblasts by 13% and 12%, respectively. These results suggest that hinokitiol exhibits antibacterial activity against a broad spectrum of pathogenic bacteria and has low cytotoxicity towards human epithelial cells.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Monoterpenos/farmacologia , Boca/microbiologia , Tropolona/análogos & derivados , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Bactérias/classificação , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fusobacterium nucleatum/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Porphyromonas gingivalis/efeitos dos fármacos , Prevotella intermedia/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus sobrinus/efeitos dos fármacos , Tropolona/farmacologia
20.
J Food Sci ; 84(6): 1513-1521, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31120593

RESUMO

Geotrichum citri-aurantii causes sour rot in citrus fruits and is responsible for important economic losses during storage. However, the availability of chemical fungicides for the control of this pathogen is limited. Thus, the aim of this research was to evaluate the antifungal efficacy of thymol and carvacrol encapsulated in 2-hydroxylpropyl-beta-cyclodextrin (HP-ß-CD) (prepared by the microwave irradiation method [MW] and solubility method [S]) for inhibition of G. citri-aurantii using in vitro bioassays broth (micro and macrodilutions methods) and inoculated food testing. Both encapsulated thymol and carvacrol were shown to be effective for inhibiting G. citri-aurantii growth in in vitro assays. Thymol was more effective in inhibiting G. citri-aurantii, while better encapsulation was provided by MW. HP-ß-CD-thymol encapsulated by MW (HP-ß-CD-thymol-MW) showed the lowest 50% effective dose (ED50 = 1.16 mM), minimum inhibitory concentration (MIC = 5.06 mM), and minimum fungicide concentration (MFC = 52.6 mM). HP-ß-CD-thymol-MW was found highly effective in reducing the growth rate and mycelial growth inhibition. Finally, HP-ß-CD-thymol-MW and HP-ß-CD-carvacrol-MW showed a higher persistent effect than thymol and carvacrol in their natural form in inhibiting this fungus. Therefore, HP-ß-CD-thymol-MW could be a promising alternative to synthetic fungicides for controlling G. citri-aurantii, the causal agent of citrus sour rot. PRACTICAL APPLICATION: Encapsulated thymol and carvacrol in HP-ß-Cyclodextrins are effective for controlling G. citri-aurantii in in vitro experiments. Encapsulation of thymol and carvacrol by microwave irradiation method (MW) was more effective than the solubility (S) method. Thymol was more effective than carvacrol, and the best results on G. citri-auriantii inhibition were achieved using the HP-ß-CD-thymol-MW method (which gave the lowest ED50 , MIC, and MFC).


Assuntos
Citrus/microbiologia , Composição de Medicamentos/métodos , Fungicidas Industriais/farmacologia , Geotrichum/efeitos dos fármacos , Monoterpenos/farmacologia , Timol/farmacologia , beta-Ciclodextrinas/química , Fungicidas Industriais/química , Geotrichum/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Monoterpenos/química , Doenças das Plantas/microbiologia , Timol/química
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