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1.
Exp Appl Acarol ; 80(3): 423-444, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31950299

RESUMO

The aim of this study was to test the effectiveness of essential oils form Piper aduncum, Melaleuca leucadendra and Schinus terebinthifolius and their blends by fumigation and residual contact on Tetranychus urticae and its natural enemy, Neoseiulus californicus. Bioassays were performed in a greenhouse with the best blend of the oils and compared to the individual oils and Vertimec® (positive control). The main constituents identified by GC-MS were dillapiole, (E)-nerolidol and limonene in the oils from P. aduncum (76.5%), M. leucadendra (87.3%) and S. terebinthifolius (unripe/ripe fruits, 42.5/34.1%). The P. aduncum and M. leucadendra oils were the most toxic to the pest. Among the blends, the greatest toxicity to T. urticae occurred by residual contact with the M. leucadendra + S. terebinthifolius ripe fruit blend (50/50). The evaluation of the effects on N. californicus showed the compatibility of the oils and blends with the predator mite for use in the integrated management of T. urticae. ß-Caryophyllene was the most toxic, independent of the method used. Based on toxicities of 11 oil constituents, the structure-activity relationship of these compounds is also discussed. This study showed that the acaricidal effect of the Piper, Melaleuca and Schinus oils can easily be increased by the binary combination of these oils. The binary blend between the oils of the Melaleuca leaves and ripe Schinus fruit in the greenhouse was effective at controlling the mite after 72 h, exhibiting the same level of toxicity as that found for the positive control (Vertimec 18 EC).


Assuntos
Acaricidas , Óleos Voláteis , Óleos Vegetais , Tetranychidae , Anacardiaceae/química , Animais , Melaleuca/química , Piper/química
2.
Planta Med ; 86(1): 32-44, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31689719

RESUMO

Gastric ulcer is a major health problem. Current treatment options of gastric ulcer, including antagonists of histamine H2 receptor and inhibitors of the proton pump, do not cure gastric ulcers, but only provide temporary relief of symptoms and can be associated with severe side effects. The lack of effective and safe medications for this global health problem urges for the discovery of novel classes of compounds with potent activity and an acceptable safety profile. Ethanol-induced ulceration in rats was used to evaluate the gastroprotective activity of casuarinin, an ellagitannin isolated from Melaleuca leucadendra. Casuarinin (25, 50, and 100 mg/kg) reduced the ulcer area by 45, 78, and 99%, respectively, compared with the ulcer group. Casuarinin (100 mg/kg) increased mucin content by 1.8-fold and reduced acidity by 42%. At the same dose, it also increased the levels of reduced glutathione by 194%, catalase by 586%, and prostaglandin E2 to its normal level. In contrast, it attenuated the ethanol-increased levels of malondialdehyde by 56%, TNF-α by 58%, and caspase-3 by 87%. Histological findings demonstrated that casuarinin exhibited a protective effect against tissue alterations in response to the ethanol-induced ulcer. Casuarinin suppressed the immunoexpression of nuclear factor-kappa B, cyclooxygenase-2, and inducible nitric oxide synthase to their normal values. It also induced the expression of heat shock protein-70, reaching up to 4.9-fold in comparison with the ulcer group. The potent gastroprotective effect of casuarinin was thus attributed to its anti-inflammatory, antioxidant, and antiapoptotic effects. Our results suggest the potential application of casuarinin as an antiulcer agent from natural sources.


Assuntos
Antiulcerosos/isolamento & purificação , Taninos Hidrolisáveis/uso terapêutico , Melaleuca/química , Extratos Vegetais/uso terapêutico , Úlcera Gástrica/prevenção & controle , Animais , Antiulcerosos/farmacologia , Ciclo-Oxigenase 2/metabolismo , Etanol , Proteínas de Choque Térmico HSP70/metabolismo , Taninos Hidrolisáveis/química , Taninos Hidrolisáveis/isolamento & purificação , Masculino , Estrutura Molecular , Mucinas/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia
3.
Braz Oral Res ; 33: e062, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31859706

RESUMO

Laboratory evidence has demonstrated the antimicrobial effect of Melaleuca alternifolia (MEL) against oral microorganisms. This randomized, double-blind, crossover clinical trial, compared the anti-biofilm and anti-inflammatory effects of MEL nanoparticles with 0.12% chlorhexidine gluconate (CHX) on biofilm-free (BF) and biofilm-covered (BC) surfaces. Before each experimental period, the participants refrained from all oral hygiene practices for 72 hours. The 60 participants were randomly assigned to professional prophylaxis in two quadrants (Q1-Q3 or Q2-Q4), and rinsed with MEL or CHX for four days. The Quigley & Hein plaque index (QHPI), gingival crevicular fluid (GCF) volume, and participants' perceptions were assessed. CHX showed significantly lower mean QHPI on BF (2.65 ± 0.34 vs. 3.34 ± 0.33, p < 0.05) and BC surfaces (2.84 ± 0.37 vs. 3.37 ± 0.33, p < 0.05). Intragroup comparisons indicated reductions in GCF in all the groups, with significant differences only for CHX on BF surfaces (p < 0.05). Intergroup comparisons revealed no significant differences (p > 0.05). Based on individual perceptions, CHX had better taste and biofilm control, but resulted in a greater change in taste. Nevertheless, MEL demonstrated anti-inflammatory effects similar to those of CHX. Further clinical trials testing different protocols, concentrations and follow-up periods are required to establish its clinical application.


Assuntos
Anti-Inflamatórios/farmacologia , Biofilmes/efeitos dos fármacos , Clorexidina/análogos & derivados , Placa Dentária/tratamento farmacológico , Melaleuca/química , Antissépticos Bucais/farmacologia , Nanopartículas/química , Adolescente , Adulto , Clorexidina/farmacologia , Estudos Cross-Over , Índice de Placa Dentária , Método Duplo-Cego , Feminino , Líquido do Sulco Gengival/efeitos dos fármacos , Humanos , Masculino , Higiene Bucal/métodos , Doenças Periodontais/microbiologia , Doenças Periodontais/prevenção & controle , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos dos fármacos , Inquéritos e Questionários , Escala Visual Analógica , Adulto Jovem
4.
Molecules ; 24(6)2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893764

RESUMO

The growing interest towards essential oils stems from their biological capabilities that include antibacterial and antioxidant effects. Such properties may be extremely useful in the reproductive field; nonetheless essential oils show toxic effects that can lead to cell disruption. The present study aimed to evaluate and compare the effects of tea tree oil (TTO) and its principal component terpinen-4-ol (TER) on the morpho-functional parameters of swine spermatozoa. Experimental samples were prepared by suspending 15 × 107 spermatozoa in 5 mL of medium with different concentrations of the above-mentioned compounds: from 0.2 to 2 mg/mL at an interval of 0.2 for TTO, while TER concentrations were adjusted according to its presence in TTO (41.5%). After 3 h incubation at 16 °C, samples were analyzed for pH, viability, acrosome status, and objective motility. The results highlighted a concentration-dependent effect of TTO with total motility as the most sensitive parameter. TER was better tolerated, and the most sensitive parameters were related to membrane integrity, suggesting a different pattern of interaction. The study confirms the importance of evaluating the effects of natural compounds on spermatozoa before exploiting their beneficial effects. Spermatozoa seem to be good candidates for preliminary toxicological screenings in the light of their peculiar properties.


Assuntos
Melaleuca/química , Espermatozoides/efeitos dos fármacos , Óleo de Melaleuca/farmacologia , Terpenos/farmacologia , Animais , Masculino , Suínos , Terpenos/química
5.
Int J Food Microbiol ; 293: 79-86, 2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30665066

RESUMO

The food industry has been valuing the quest for natural substances for use in food preservation aiming to meet consumer demand for safer, more natural foods with preserved nutrients. This study aimed to assess the antimicrobial potential of essential oil of Melaleuca alternifolia (EOMA) in the inhibition of Listeria monocytogenes (ATCC 7644) (L. monocytogenes) in ground beef. An in vitro screening in solid phase was performed and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined through microdilution test. The time of action of EOMA was assessed through the death-time curve at 2 × MIC and MBC. The effects of MBC on bacterial morphology were verified under scanning electron microscopy (SEM). The meat samples were inoculated with four different suspensions of L. monocytogenes (1.5 × 108 CFU/mL, 4.6 × 104 CFU/mL, 9.2 × 103 CFU/mL, and 1.2 × 102 CFU/mL) and stored at 4 ±â€¯1 °C for up to 14 days. The test samples were added with 1.5% v/w EOMA. The test of diffusion in solid medium showed L. monocytogenes ATCC 7644 was extremely sensitive to EOMA. MIC and MBC values were 0.10 µL/g and 0.15 µL/mL, respectively. The death-time curve revealed a reduction of viable cells after 1 h of contact with the oil. SEM showed that the treated cells had wrinkled surface and some cells had lower size and diameter when compared to control ones. The food matrix test indicated EOMA had antimicrobial activity in all samples except for the one inoculated with the suspension at 1.5 × 108 CFU/mL. Thus, the use of essential oil of Melaleuca alternifolia as a potential natural antimicrobial agent to preserve ground beef was promising as it was effective at low concentration. The data lay bases for new tests to be carried out in other food matrices.


Assuntos
Contaminação de Alimentos/prevenção & controle , Listeria monocytogenes/efeitos dos fármacos , Melaleuca/química , Óleos Voláteis/farmacologia , Carne Vermelha/microbiologia , Animais , Anti-Infecciosos/farmacologia , Bovinos , Microbiologia de Alimentos , Conservação de Alimentos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Chá/química
6.
Curr Med Chem ; 26(29): 5501-5541, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30182844

RESUMO

A number of papers reporting antimicrobial properties of extracts, essential oils, resins and various classes of compounds isolated from higher plants have been published in recent years; however, a comprehensive analysis of plant-derived antimicrobial agents currently applied in practice for the improvement of human health is still lacking. This review summarizes data on clinical efficacy, antimicrobial effects and the chemistry of commercially available antibacterial and antifungal agents of plant origin currently used in the prevention and treatment of gastrointestinal, oral, respiratory, skin, and urinary infections. As a result of an analysis of the literature, more than 40 plant-derived over-the-counter pharmaceuticals, dietary supplements, cosmetics, herbal medicines, and functional foods containing complex mixtures (e.g. Glycyrrhiza glabra extract, Melaleuca alternifolia essential oil, and Pistacia lentiscus resin), pure compounds (e.g. benzoic acid, berberine, eucalyptol, salicylic acid and thymol) as well as their derivatives and complexes (e.g. bismuth subsalicylate and zinc pyrithione) have been identified. The effectiveness of many of these products is illustrated by results of clinical trials and supported by data on there in vitro antimicrobial activity. A broad spectrum of various commercial products currently available on the market and their welldocumented clinical efficacy suggests that plants are prospective sources for the identification of new types of antimicrobial agents in future. Innovative approaches and methodologies for effective proof-of-concept research and the development of new types of plant-derived products effective against recently emerging problems related to human microbial diseases (e.g. antimicrobial resistance) are also proposed in this review.


Assuntos
Antibacterianos/uso terapêutico , Antifúngicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Extratos Vegetais/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Glycyrrhiza/química , Humanos , Melaleuca/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pistacia/química
7.
Curr Microbiol ; 76(1): 108-116, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30421144

RESUMO

Melaleuca alternifolia tea tree oil (TTO) is largely used in cutaneous infections. Clinical observations reported antibacterial, antifungal, and antiviral activities, whereas in vitro experiments ascribed most of biological properties to terpinen-4-ol. Since different plant chemotypes and storage conditions result in variations of chemical composition of commercially available TTO, in this study we investigated the antimicrobial activity and the chemical profile of ten commercially available TTO products. The antimicrobial activity was assessed against Candida glabrata, Herpes simplex virus type 1 (HSV-1), methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa grown in planktonic mode or biofilms. Only five out of ten TTO batches reported significant antimicrobial activity. The identified TTO products reduced bacterial survival in biofilms, generated oxidative damage in C. glabrata, and diminished HSV-1 infectivity. GC-MS analysis revealed that all the analyzed TTO batches fitted into the terpinen-4-ol chemotype even if we reported great variability in composition of nine major ISO-specified TTO components. Overall, we were not able to ascribe the antimicrobial activity to the content in terpinen-4-ol. We therefore conclude that the antimicrobial activity of TTO results from complex interaction among different components.


Assuntos
Anti-Infecciosos/farmacologia , Candida glabrata/crescimento & desenvolvimento , Herpesvirus Humano 1/crescimento & desenvolvimento , Melaleuca/química , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Pseudomonas aeruginosa/crescimento & desenvolvimento , Óleo de Melaleuca/farmacologia , Biofilmes/efeitos dos fármacos , Candida glabrata/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Terpenos/farmacologia
8.
Phytother Res ; 33(2): 461-470, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30506741

RESUMO

The hepatoprotective activity of praecoxin A, an ellagitannin from Melaleuca ericifolia, was determined against CCl4 -induced toxicity in mice. Praecoxin A was administered (25, 50, and 100 mg/kg) for 5 days followed by CCl4 . Praecoxin A markedly ameliorated the CCl4 -induced increase in AST (by 19, 52, and 56%), ALP (22, 45, and 48%), ALT (11, 47, and 54%), total bilirubin (14, 27, and 28%), and MDA (26, 44, and 51%) at the tested doses, respectively, as compared with CCl4 group. It was evident that praecoxin A significantly (p < 0.001) increased the antioxidant parameters GSH (45, 99, and 137%) and SOD (61, 129, and 159%). Histological findings revealed a marked amelioration of hepatocyte degeneration, necrosis, inflammatory cell infiltration, and hemorrhage in the groups treated with praecoxin A. COX-2 and caspase-3 hepatic expressions were significantly downregulated (p < 0.001) in praecoxin A-treated groups (up to 57, 83, and 93% for COX-2 and by 30, 82, and 99% for caspase-3). These findings suggest that praecoxin A exerts a beneficial effect against oxidative stress by reducing lipid peroxidation, enhancing the antioxidant defense status, and protecting against the histopathological changes induced by CCl4 . This study highlights a promising natural hepatoprotective candidate derived from M. ericifolia that might be an alternative to silymarin.


Assuntos
Taninos Hidrolisáveis/farmacologia , Hepatopatias/prevenção & controle , Melaleuca/química , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Inflamação/tratamento farmacológico , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Necrose/tratamento farmacológico , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia
9.
Nat Prod Res ; 33(17): 2545-2548, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29537894

RESUMO

To identify the natural antifungal agents, the antifungal activities of Melaleuca leucadendra (L.) L. essential oil (ML-EO) from Fujian Province of China were assayed. Treatment of ML-EO in combination with the front-line using antibiotics against Candida led to synergistic effects. Electron microscopy analysis on the oil treated C. albicans cells revealed the formation of mesosome-like structures, suggesting well the membrane damage caused by the essential oil. The Griess assay by monitoring NO production in LPS-stimulated RAW264.7 cells indicated the potent anti-inflammatory activity of ML-EO. In comparison with the marked essential oil of Melaleuca alternifolia EO, ML-EO had almost the same chemical components. In general, the antifungal activity of ML-EO and its synergistic interactions with conventional antibiotics were able to lead the development of new treatment strategies on Candida infection.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/isolamento & purificação , Candida/efeitos dos fármacos , Melaleuca/química , Óleos Voláteis/química , Anti-Inflamatórios/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , China , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana
10.
J Environ Qual ; 47(6): 1487-1495, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30512059

RESUMO

Biochar has been heralded for improving soil quality, sequestering C, and converting organic residues into value-added amendments. Biochar research in agricultural settings has been primarily conducted on acidic soils, with few studies evaluating biochar effects on alkaline soils. Given the rise of small-scale, sustainable farmers experimenting with biochar in South Florida's alkaline, carbonaceous soil, this study sought to assess biochar use in South Florida using an invasive plant species as a feedstock. (Cav.) S.T. Blake biomass was converted into biochar to measure how application at two rates, 2 and 5% (w/w), affects plant growth, soil macro- and micronutrients, and microbial gas flux (CO) in a potted greenhouse experiment using L. Plant growth was inhibited with biochar addition at the 2 and 5% rates. Dry shoot, pod weight, and pod length decreased significantly between treatments ( < 0.001). Significant reductions in plant-available P, Ca, Mg, Cu, and Zn were observed in the 5% biochar soil postharvest ( < 0.05). Compared with the control, addition of biochar at 2 and 5% rates significantly reduced CO flux during the growing season, but not at harvest ( < 0.01). Our results indicate that those considering biochar application in South Florida's alkaline soil should be cautious in selecting feedstock and temperature for biochar production. Biochar can be produced at lower temperatures to decrease pH, but the concomitant increase in volatile matter (VM) is of concern. Although CO flux may have decreased, the deleterious impacts of biochar (pH = 8.12, VM = 26.5%) on production should not be dismissed.


Assuntos
Agricultura/métodos , Poluentes Atmosféricos/análise , Carvão Vegetal/química , Fertilizantes , Dióxido de Carbono/análise , Florida , Melaleuca/química , Nitrogênio/análise , Óxido Nitroso/análise , Phaseolus , Fósforo/análise , Solo , Microbiologia do Solo
11.
Molecules ; 23(10)2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30304862

RESUMO

PURPOSE: Herein, an extended investigation of Tea tree oil (TTO) against a number of multi-drug resistant (MDR) microorganisms in liquid and vapor phases is reported. METHODS: The activity of TTO was tested against methicillin-sensitive Staphylococcus aureus (MSSA), Escherichia coli, and clinical strains of methicillin-resistant S. aureus (MRSA), extended-spectrum beta lactamases producer carbapenem-sensitive Klebsiella pneumoniae (ESBL-CS-Kp), carbapenem-resistant K. pneumoniae (CR-Kp), Acinetobacter baumannii (CR-Ab), and Pseudomonas aeruginosa (CR-Pa). Minimal inhibitory/bactericidal concentrations (MIC/MBCs) and synergistic activity between TTO and different antimicrobials were determined. In the vapor assay (VP), TTO-impregnated discs were placed on the lid of a petri dish and incubated for 24 h at 37 °C. RESULTS: TTO showed a potent bactericidal activity against all the tested microorganisms. TTO in combination with each reference antimicrobial showed a high level of synergism at sub-inhibitory concentrations, particularly with oxacillin (OXA) against MRSA. The VP assay showed high activity of TTO against CR-Ab. CONCLUSION: Evaluation of in-vitro activity clearly indicated TTO as a potential effective antimicrobial treatment either alone or in association with known drugs against MDR. Therefore, TTO could represent the basis for a possible role in non-conventional regimens against S. aureus and Gram-negative MDR. TTO in VP might represent a promising option for local therapy of pneumonia caused by CR-Ab.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Bactérias Gram-Negativas/efeitos dos fármacos , Melaleuca/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleo de Melaleuca/farmacologia , Antibacterianos/química , Sinergismo Farmacológico , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Óleo de Melaleuca/química
12.
Molecules ; 23(10)2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30336602

RESUMO

The problem of antibiotic resistance among pathogens encourages searching for novel active molecules. The aim of the research was to assay the anti-quorum sensing (anti-QS) and antibiofilm potential of Melaleuca alternifolia essential oil and its main constituent, terpinen-4-ol, to prevent the infections due to methicillin-resistant Staphylococcus aureus strains as an alternate to antibiotics. The tea tree oil (TTO) was evaluated for its potential in inhibiting QS-dependent phenomena such as violacein production in Chromobacterium violaceum, swarming motility of Pseudomonas aeruginosa PAO1, and biofilm formation in MRSA strains on glass. The results showed that terpinen-4-ol was able to inhibit MRSA strain biofilm formation on the glass strips by 73.70%. TTO inhibited the violacein production at a mean inhibitory concentration (MIC) value of 0.048 mg/mL by 69.3%. At 100 µg/mL TTO and terpinen-4-ol exhibited inhibition in swarming motility of PAO1 by 33.33% and 25%, respectively. TTO revealed anti-QS and anti-biofilm activities at very low concentrations, but it could be further investigated for new molecules useful for the treatment of MRSA infections.


Assuntos
Chromobacterium/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Terpenos/farmacologia , Biofilmes/efeitos dos fármacos , Chromobacterium/patogenicidade , Humanos , Melaleuca/química , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Percepção de Quorum/efeitos dos fármacos , Infecções Estafilocócicas/microbiologia , Óleo de Melaleuca/farmacologia , Terpenos/química
13.
Molecules ; 23(10)2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30279388

RESUMO

Melaleuca styphelioides, known as the prickly-leaf tea tree, contains a variety of bioactive compounds. The purposes of this study were to characterize the polyphenols extracted from Melaleuca styphelioides leaves and assess their potential antioxidant and anti-inflammatory effects. The polyphenol extracts were prepared by maceration with solvents of increasing polarity. The LC/MS-MS technique was used to identify and quantify the phenolic compounds. An assessment of the radical scavenging activity of all extracts was performed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonate) (ABTS⁺), and ferric reducing antioxidant power (FRAP) assays. The anti-inflammatory activity was determined on interferon gamma (IFN-γ)/histamine (H)-stimulated human NCTC 2544 keratinocytes by Western blot and RT-PCR. Compared to other solvents, methanolic extract presented the highest level of phenolic contents. The most frequent phenolic compounds were quercetin, followed by gallic acid and ellagic acid. DPPH, ABTS⁺, and FRAP assays showed that methanolic extract exhibits strong concentration-dependent antioxidant activity. IFN-γ/H treatment of human NCTC 2544 keratinocytes induced the secretion of high levels of the pro-inflammatory mediator inter-cellular adhesion molecule-1 (ICAM-1), nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa B (NF-κB), which were inhibited by extract. In conclusion, the extract of Melaleuca styphelioides leaves is rich in flavonoids, and presents antioxidant and anti-inflammatory proprieties. It can be proposed as a useful compound to treat inflammatory skin diseases.


Assuntos
Inflamação/tratamento farmacológico , Queratinócitos/efeitos dos fármacos , Melaleuca/química , Polifenóis/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Linhagem Celular , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Histamina/toxicidade , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Interferon gama/toxicidade , Queratinócitos/patologia , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/isolamento & purificação , Polifenóis/farmacologia
14.
Pesqui. vet. bras ; 38(8): 1597-1607, Aug. 2018. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-976469

RESUMO

Otitis externa is a common complaint in dogs. Bacteria and yeasts are commonly involved and may perpetuate inflammatory reactions inside the ear canal. Otoscopy, cytological examination of secretion and microbiological culture embody forms of diagnosis. Cytology also has great use in accessing treatment evolution. Therapy usually consists of cleaning ear canals and subsequent use of antibiotics or antifungal products. As some of them may cause hypersensitivity and even ototoxicity, searching for new pharmacological bases is currently necessary and justifies this study, which aimed to evaluate in vitro and in vivo efficacy of tea tree essential oil for bacterial and yeast ear infections in dogs. Twenty-eight dogs from a particular shelter in Cuiabá (Mato Grosso, Brazil), presenting clinical signs of otitis externa, were enrolled in this clinical trial. In all of them, clinical and cytological evaluations, as well as culture and susceptibility testing of the affected ears were carried out. From each dog, one ear was treated with 5% tea tree essential oil lotion and the other with standard otic formulation, according to the type of infection (bacterial, yeast or both). In vitro susceptibility testings of all ear cultures, to the same drugs used in treatment, were also carried out. Culture results showed 62.5% bacterial and fungal infection, 33.9% bacterial infection and 3.6% fungal infection, from the 56 ear samples collected. The most common microorganisms isolated were Staphylococcus intermedius, Staphylococcus aureus, Proteus mirabilis and Malassezia pachydermatis. Gram-positive bacteria were susceptible to gentamycin in 60.5% and resistant in 16.3% of the samples. Five percent tea tree essential oil formulation produced a 5mm clear zone of inhibition around the disks in one of the 63 samples evaluated. Pure (100%) tea tree essential oil formulation produced a 10mm clear zone of inhibition around the disks in four of the 63 samples evaluated, a 9mm zone in three samples, an 8mm zone in 16 samples, a 7mm zone in seven samples, a 6mm zone in two samples and there was no clear zone in 31 samples. Inhibition zones were produced by strains of Staphylococcus intermedius, Staphylococcus hyicus, Corynebacterium sp., Proteus mirabilis and Enterobacter sp. tea tree essential oil ear solution significantly induced remission of clinical signs both in bacterial and yeast ear infections. It also reduced as much Malassezia pachydermatis ear infection as the nystatin solution used in this study, while gentamycin solution showed better antibacterial effect. More studies should be conducted to evaluate in vitro diffusion properties of tea tree essential oil. Good antimicrobial spectrum and the absence of adverse reactions confirm the importance of developing a tea tree formulation as an alternative therapy for ear infections in dogs.(AU)


Otite externa é queixa frequente em cães. Bactérias e leveduras estão comumente envolvidas e podem perpetuar as reações inflamatórias dentro do canal auditivo. Dentre as formas de diagnóstico, encontram-se a otoscopia, o exame citológico da secreção e a cultura microbiológica. Citologia também tem grande utilidade no acesso à evolução do tratamento. A terapia consiste de limpeza dos canais auditivos e posterior utilização de antibióticos ou produtos antifúngicos. Como alguns antimicrobianos utilizados no tratamento podem causar hipersensibilidade e até mesmo ototoxicidade, a busca por novas bases farmacológicas justifica a existência deste estudo, que teve como objetivo avaliar in vitro e in vivo a eficiência do óleo de Melaleuca alternifolia em otites bacterianas e fúngicas de cães. Vinte e oito cães, de um abrigo particular, apresentando sinais clínicos de otite externa, foram incluídos neste estudo clínico. Todos passaram por avaliação clínica, citologia e cultura de material das orelhas afetadas. De cada animal, uma orelha foi tratada com óleo de Melaleuca 5% e a outra com formulação ótica padrão, de acordo com a afecção (bacteriana, fúngica ou mista). As culturas também foram submetidas a testes de susceptibilidade in vitro aos mesmos agentes utilizados no tratamento in vivo. Os resultados da cultura mostraram 62,5% de infecção mista (bacteriana e fúngica), 33,9% de infecção bacteriana e 3,6%, de infecção fúngica a partir das 56 orelhas. Os micro-organismos mais isolados foram Staphylococcus intermedius, Staphylococcus aureus, Proteus mirabilis e Malassezia pachydermatis. As bactérias GRAM-positivas foram sensíveis à gentamicina em 60,5% e resistentes em 16,3% das amostras. A formulação com 5% de óleo essencial de Melaleuca produziu uma zona de inibição de 5mm em torno dos discos em uma das 63 amostras avaliadas. A formulação pura (100%) do mesmo produto produziu uma zona de 10mm de inibição em quatro das 63 amostras analisadas, uma zona de 9 mm em três amostras, uma zona de 8mm em 16 amostras, uma zona de 7mm em sete amostras, uma zona de 6mm em duas amostras e não havia nenhuma zona clara em 31 amostras. Zonas de inibição foram produzidas por estirpes de Staphylococcus intermedius, Staphylococcus hyicus, Corynebacterium sp., Proteus mirabilis e Enterobacter sp. Clinicamente, a formulação com o óleo essencial de melaleuca induziu significativamente uma melhora nas manifestações, tanto nas otites bacterianas quanto nas causadas por leveduras, sendo estatisticamente semelhante ao tratamento com nistatina (nas otites por levedura), mas menos eficaz que a solução de gentamicina nas otites bacterianas. Mais estudos devem ser realizados para avaliar as propriedades de difusão in vitro do óleo essencial de melaleuca. O bom espectro antimicrobiano, a boa resposta clínica e a ausência de reações adversas confirmam a possibilidade de desenvolvimento de formulação ótica com o óleo essencial de melaleuca, como uma alternativa para a terapia de infecções do ouvido em cães.(AU)


Assuntos
Otite/microbiologia , Óleos Voláteis/síntese química , Melaleuca/química , Fitoterapia/estatística & dados numéricos
15.
Microb Pathog ; 123: 47-51, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29959037

RESUMO

Some evidence has demonstrated that Ichthyophthirius multifiliis, etiologic agent of "white spot disease", causes severe bioenergetics dysfunction in the spleen of naturally infected silver catfish (Rhamdia quelen), which contributes directly to disease pathogenesis. Recently, several studies have demonstrated the efficacy of Melaleuca alternifolia essential oil, popularly known as tea tree oil (TTO), in the treatment of freshwater fish naturally or experimentally infected with I. multifiliis. In this sense, the aim of this study was to evaluate whether TTO is capable of preventing or reducing splenic bioenergetics dysfunction in silver catfish naturally infected with I. multifiliis. Splenic cytosolic and mitochondrial creatine kinase (CK) and pyruvate kinase (PK) activities decreased in infected animals compared to uninfected animals, while adenylate kinase (AK) activity increased. Treatment with TTO was able to prevent the inhibition on splenic CK and PK activities but was not able to prevent the stimulation of AK activity. Based on this evidence, treatment with TTO prevents the impairment on energetic metabolism via improvement of enzymes belonging to the phosphotransfer network, such as CK and PK. In summary, this treatment can be considered an interesting approach to prevent the bioenergetics imbalance in spleen of silver catfish naturally infected with I. multifiliis.


Assuntos
Infecções por Cilióforos/tratamento farmacológico , Metabolismo Energético/efeitos dos fármacos , Doenças dos Peixes/tratamento farmacológico , Hymenostomatida/efeitos dos fármacos , Melaleuca/química , Óleo de Melaleuca/uso terapêutico , Adenilato Quinase/metabolismo , Animais , Peixes-Gato , Creatina Quinase/metabolismo , Doenças dos Peixes/parasitologia , Mitocôndrias/metabolismo , Piruvato Quinase/metabolismo , Baço/metabolismo
16.
Biomed Res Int ; 2018: 2396109, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854733

RESUMO

The in vitro antioxidant and antimicrobial activity of the essential oil from Melaleuca alternifolia (M. alternifolia) was evaluated in this report. The antioxidant potential of the essential oil from M. alternifolia was evaluated by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, thiobarbituric acid reactive species (TBARS) assay, and the hydroxyl radical scavenging activity method. The essential oil from M. alternifolia was able to reduce DPPH with an EC50 (concentration for 50% of maximal effect) of 48.35 µg/ml, inhibit the lipid peroxidation with an IC50 (50% inhibitory concentration) of 135.9 µg/ml, and eliminate hydroxyl radicals with an EC50 of 43.71 µg/ml. Antimicrobial screening, minimum inhibitory concentration, and minimum bactericidal concentration assays showed that the essential oil from M. alternifolia inhibited strongly the growth of different types of microorganisms, including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Penicillium italicum Wehmer, and Penicillium digitatum Sacc. Thus, the essential oil of M. alternifolia possesses antioxidant and antimicrobial activity and could be suitable for use as a natural preservative ingredient in food, agriculture, and pharmaceutical industries.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Melaleuca/química , Óleos Voláteis/farmacologia , Bactérias/efeitos dos fármacos , Compostos de Bifenilo/química , Depuradores de Radicais Livres/química , Fungos/efeitos dos fármacos , Radical Hidroxila/química , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Picratos/química
17.
Braz. j. microbiol ; 49(2): 212-219, Apr.-June 2018. tab
Artigo em Inglês | LILACS | ID: biblio-889241

RESUMO

Abstract The evolution of microorganisms resistant to many medicines has become a major challenge for the scientific community around the world. Motivated by the gravity of such a situation, the World Health Organization released a report in 2014 with the aim of providing updated information on this critical scenario. Among the most worrying microorganisms, species from the genus Candida have exhibited a high rate of resistance to antifungal drugs. Therefore, the objective of this review is to show that the use of natural products (extracts or isolated biomolecules), along with conventional antifungal therapy, can be a very promising strategy to overcome microbial multiresistance. Some promising alternatives are essential oils of Melaleuca alternifolia (mainly composed of terpinen-4-ol, a type of monoterpene), lactoferrin (a peptide isolated from milk) and chitosan (a copolymer from chitin). Such products have great potential to increase antifungal therapy efficacy, mitigate side effects and provide a wide range of action in antifungal therapy.


Assuntos
Anti-Infecciosos/farmacologia , Produtos Biológicos/farmacologia , Candida/efeitos dos fármacos , Quitosana/farmacologia , Lactoferrina/farmacologia , Melaleuca/química , Anti-Infecciosos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Candidíase/tratamento farmacológico , Quitosana/isolamento & purificação , Lactoferrina/isolamento & purificação
18.
Parasitology ; 145(12): 1510-1520, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29667560

RESUMO

Australian tea tree oil (TTO) and its extract terpinen-4-ol (T4O) are found to be effective in moderating demodex-related diseases. Their possible effects are lowering the mite counts, relieving the demodex-related symptoms and modulating the immune system especially the inflammatory response. This review summarizes the topical treatments of TTO and T4O in human demodicosis, their possible mechanism of actions, side-effects and potential resistance in treating this condition. Although current treatments other than TTO and T4O are relatively effective in controlling the demodex mite population and the related symptoms, more research on the efficacy and drug delivery technology is needed in order to assess its potential as an alternative treatment with minimal side-effect profile, low toxicity and low risk of demodex resistance.


Assuntos
Melaleuca/química , Infestações por Ácaros/tratamento farmacológico , Ácaros/fisiologia , Óleo de Melaleuca/farmacologia , Terpenos/farmacologia , Animais , Humanos , Infestações por Ácaros/parasitologia , Pele/parasitologia , Óleo de Melaleuca/química , Óleo de Melaleuca/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação
19.
Pharmazie ; 73(1): 61-64, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29441953

RESUMO

Leaves of Melaleuca leucadendra contain the novel flavonol glycoside, myricetin 3-O-ß-4C1-galactopyranuronoid. In addition, known fifteen phenolics were identified. All isolates are characterized for the first time from this plant. Structures were established by conventional methods and confirmed by spectral methods of analysis, including one and two-dimensional nuclear magnetic resonance spectroscopy (1D and 2D-NMR) and high resolution electro-spray ionization mass spectrometry (HRESIMS), as well. Assessment of some immunological and biological efficacy, of the extract in combination with a parallel cytotoxicity evaluation, using the method of cellular reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) technique was carried out. Besides, evaluation of the antioxidant effectiveness, using the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the oxygen radical absorption capacity (ORAC) methods was performed. In addition, the cytotoxicity against liver (Huh-7), breast (MCF-7) and prostate (PC-3) cancers using the neutral red assay (NRU) technique for the extract and the new flavonol glycoside also, was assessed.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Melaleuca/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Flavonóis/isolamento & purificação , Flavonóis/farmacologia , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Células MCF-7 , Espectroscopia de Ressonância Magnética , Masculino , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Espectrometria de Massas por Ionização por Electrospray
20.
Phytother Res ; 32(2): 230-242, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29235165

RESUMO

This is a systematic review of clinical and laboratory studies evaluating the effect of Melaleuca alternifolia on periodontopathogens, dental plaque, gingivitis, periodontitis, and inflammatory responses. The PubMed, Cochrane, Web of science, Bireme, Lilacs, Prospero, Open Grey, and Clinical Trials databases were searched to identify potentially eligible studies through October 2016. Of 1,654 potentially eligible studies, 25 were included in the systematic review. Their methodology was evaluated through the Cochrane Handbook for clinical studies and the GRADE system for in vivo/in vitro studies. Although clinical studies must be interpreted with caution due to methodological limitations, laboratory studies have found promising results. In vitro evidences showed that M. alternifolia has bactericidal and bacteriostatic effects against the most prevalent periodontopathogens. Clinical studies found comparable effects to chlorhexidine 0.12% in reducing gingival inflammation, although the antiplaque effect was lower. M. alternifolia also showed antioxidant properties, which are beneficial to the host, allied to the reduction on immune-inflammatory responses to pathogens. This systematic review suggests that the M. alternifolia has potential anti-inflammatory and antimicrobial properties, which can be easily applied to the periodontal tissues. However, further clinical trials are needed to elucidate the clinical relevance of its application.


Assuntos
Antibacterianos/uso terapêutico , Placa Dentária/tratamento farmacológico , Melaleuca/química , Doenças Periodontais/tratamento farmacológico , Antibacterianos/farmacologia , Humanos
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