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1.
Molecules ; 26(24)2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-34946747

RESUMEN

The increase in antibiotic resistance and the emergence of new bacterial infections have intensified the research for natural products from plants with associated therapy. This study aimed to verify the antibacterial and antioxidant activity of crude extracts of the genus Plectranthus species, being the first report on the modulation of aminoglycosides antibiotic activity by Plectranthus amboinicus extracts. The chemical composition was obtained by chemical prospecting and High-Performance Liquid Chromatography with diode arrangement detector (HPLC/DAD). The antibacterial activities of the extracts alone or in association with aminoglycosides were analyzed using the microdilution test. The antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. The phytochemical prospection allowed the flavonoids, saponins, tannins and triterpenoids to be identified. Quercetin, rutin, gallic acid, chlorogenic acid, caffeic acid, catechin, kaempferol, glycosylated kaempferol, quercitrin, and isoquercitrin were identified and quantified. The principal component analysis (PCA) observed the influence of flavonoids and phenolic acids from Plectranthus species on studied activities. Phytochemical tests with the extracts indicated, especially, the presence of flavonoids, confirmed by quantitative analysis by HPLC. The results revealed antibacterial activities, and synergistic effects combined with aminoglycosides, as well as antioxidant potential, especially for P. ornatus species, with IC50 of 32.21 µg/mL. Multivariate analyzes show that the inclusion of data from the antioxidant and antibacterial activity suggests that the antioxidant effect of these species presents a significant contribution to the synergistic effect of phytoconstituents, especially based on the flavonoid contents. The results of this study suggest the antibacterial activity of Plectranthus extracts, as well as their potential in modifying the resistance of the analyzed aminoglycosides.


Asunto(s)
Antibacterianos/química , Antioxidantes/química , Quimiometría , Extractos Vegetales/química , Plectranthus/química
2.
Curr Pharm Des ; 26(33): 4056-4091, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32209036

RESUMEN

Species from the Annona (Anonaceae) genus are used in traditional medicine for the treatment of various diseases. Ethnobotanical studies provide information regarding the plant part and the preparation method being used, while scientific studies such as in vitro, in vivo, and clinical tests can provide evidence supporting ethnopharmacological reports, directing studies towards the isolation of compounds which may be active for specific pathologies. Annona muricata and Annona squamosa were the most commonly reported species from those studied, with Annona cherimola and Annona classiflora also standing out. Acetogenins were the most commonly isolated metabolite class due to their cytotoxic properties, with flavonoids, alkaloids, steroids, and peptides also being reported. Many species from the Annona genus have proven biological activities, such as antitumor, antioxidant, antimicrobial and antifungal. The present review had as its objective to facilitate access to ethnobotanical, chemical and biological information in order to direct future researches.


Asunto(s)
Annona , Etnobotánica , Etnofarmacología , Humanos , Medicina Tradicional , Fitoterapia , Extractos Vegetales/farmacología
3.
Nat Prod Res ; 34(22): 3239-3243, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30663376

RESUMEN

In this study the physicochemical characterization of the pulp and almond fixed oil was carried out; their antibacterial activity and aminoglycoside antibiotic modifying action against standard and multiresistant Gram-positive and -negative bacteria were investigated using the broth microdilution assay. Physical properties such as moisture, pH, acidity, peroxide index, relative density and refractive index indicate stability and chemical quality of the oils. In the GC/MS chemical composition analysis, a high unsaturated fatty acid content and the presence of oleic and palmitic acids were observed in the oils. In the antibacterial assay, more significant results were obtained for Escherichia coli, while other standard and multi-resistant strains presented MIC values ≥ 1024 µg/mL. Furthermore, the fixed oils in association with antibiotics were able to significantly improve antibacterial activity against S. aureus with a reduction in MICs.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Malpighiales/química , Aceites de Plantas/farmacología , Aminoglicósidos/farmacología , Escherichia coli/efectos de los fármacos , Ácidos Grasos/análisis , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Aceites de Plantas/química , Staphylococcus aureus/efectos de los fármacos
4.
Chem Biodivers ; 16(12): e1900313, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31545879

RESUMEN

Cissampelos sympodialis Eichler is well studied and investigated for its antiasthmatic properties, but there are no data in the literature describing antibacterial properties of alkaloids isolated from this botanical species. This work reports the isolation and characterization of phanostenine obtained from roots of C. sympodialis and describes for the first time its antimicrobial and antibiotic modulatory properties. Phanostenine was first isolated from Cissampelos sympodialis and its antibacterial activities were determined. Chemical structures of the alkaloid isolate were determined using spectroscopic and chemical analyses. Phanostenine was also tested for its antibacterial activity against standard strains and clinical isolates of Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentration (MIC) was determined in a microdilution assay and for the evaluation of antibiotic resistance-modifying activity. MIC of the antibiotics was determined in the presence or absence of phanostenine at sub-inhibitory concentrations. The evaluation of antibacterial activity by microdilution assay showed activity for all strains with better values against S. aureus ATCC 12692 and E. coli 27 (787.69 mm). The evaluation of aminoglycoside antibiotic resistance-modifying activity showed reduction in the MIC of the aminoglycosides (amikacin, gentamicin and neomycin) when associated with phanostenine, MIC reduction of antibiotics ranging from 21 % to 80 %. The data demonstrated that phanostenine possesses a relevant ability to modify the antibiotic activity in vitro. We can suggest that phanostenine presents itself as a promising tool as an adjuvant for novel antibiotics formulations against bacterial resistance.


Asunto(s)
Alcaloides/química , Antibacterianos/química , Derivados del Benceno/química , Cissampelos/química , Compuestos Heterocíclicos de 4 o más Anillos/química , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Derivados del Benceno/aislamiento & purificación , Derivados del Benceno/farmacología , Cissampelos/metabolismo , Farmacorresistencia Bacteriana/efectos de los fármacos , Compuestos de Anillos Fusionados , Compuestos Heterocíclicos de 4 o más Anillos/aislamiento & purificación , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Staphylococcus aureus/efectos de los fármacos
5.
Ecotoxicol Environ Saf ; 170: 461-467, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30553924

RESUMEN

The objective of this work was to evaluate the antioxidant, metal chelating and cytoprotective activity of the Eugenia jambolana Lam. extract, as well as of its flavonoid and tannic fractions, against the action of Mercury Chloride (HgCl2). Flavonoids were quantified and an LC-MS chromatographic analysis was performed to identify secondary metabolites. Fe2+ and Fe3+ chelation tests and antioxidant activity were carried out using the FRAP method. Microbiological tests were performed by microdilution to determine the Minimum Inhibitory Concentration (MIC). From these results the Minimum Bactericidal (MBC) and Minimum Fungicide Concentration (MFC) were evaluated. The allelopathy and cytoprotection assays were performed using eukaryotic and prokaryotic models. The results revealed the presence of phenolic acids and flavonoids in the E. jambolana extract and fractions. The sub-allelopathic concentration (64 µg/mL) was used and the results demonstrated the E. jambolana potential cytoprotective effect against mercury chloride.


Asunto(s)
Productos Biológicos/química , Cloruro de Mercurio/toxicidad , Syzygium/química , Alelopatía , Antiinfecciosos/química , Antioxidantes/química , Citoprotección , Flavonoides/química , Lactuca/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química
6.
J Hazard Mater ; 370: 54-62, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29602643

RESUMEN

This study aimed to verify the chelating, antioxidant and cytoprotective activities of Psidium brownianum Mart. Ex DC against mercury and aluminum. The ethanolic extract, as well as the tannic and flavonoid fractions, were prepared and subjected to liquid chromatography-mass spectrometry analysis. Ferric ion reduction and antioxidant activity measurement using the FRAP method were performed with P. brownianum. After determining the sub-allelopathic doses, germination tests using Lactuca sativa (lettuce) seeds were performed. The main compounds identified in the extract and fractions were: quercetin and its derivatives; myricetin and its derivatives; gallic acid; ellagic acid; quinic acid and gallocatechin. The Minimum Inhibitory Concentration (MIC) for all samples were ≥ 1024 µg/mL. The flavonoid fraction in association with mercury chloride demonstrated cytoprotection (p < 0.001). The sub-allelopathic concentration used was 64 µg/mL. The extract and fractions were cytoprotective for radicles and caulicles when assayed in association with mercury and against aluminum for radicles. This suggests that the P. brownianum extract and its fractions present cytoprotective activity, possibly related to the antioxidant effect of secondary metabolites, especially flavonoids.


Asunto(s)
Cloruro de Aluminio/toxicidad , Antioxidantes/farmacología , Quelantes/farmacología , Cloruro de Mercurio/toxicidad , Extractos Vegetales/farmacología , Psidium , Alelopatía , Antioxidantes/química , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Quelantes/química , Cromatografía Liquida , Citoprotección , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Flavonoides/análisis , Flavonoides/farmacología , Germinación/efectos de los fármacos , Hierro/química , Lactuca/efectos de los fármacos , Lactuca/crecimiento & desarrollo , Espectrometría de Masas , Extractos Vegetales/química
7.
Biomed Res Int ; 2017: 1928171, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28951867

RESUMEN

The Protium heptaphyllum species, also known as Almécega, produces an oily resin, used in folk medicine as an analgesic and anti-inflammatory agent, in healing, and as an expectorant, which is rich in pentacyclic triterpenes and essential oils. In this study, the essential oil obtained by hydrodistillation of Almécega's resin was analyzed by gas chromatography-triple quadrupole mass spectrometry and evaluated for chemical composition and vasorelaxant activity in rat superior mesenteric artery. The main constituents determined by gas chromatography-triple quadrupole mass spectrometry were limonene, p-cineole, and o-cymene. In intact rings precontracted with phenylephrine (Phe 1 µM), EOPh (3-750 µg/mL) induced relaxation, and the essential oil had a concentration-dependent vasorelaxant effect, without involvement of endothelial mediators.


Asunto(s)
Burseraceae/química , Aceites Volátiles/química , Analgésicos/química , Analgésicos/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Ciclohexenos/química , Ciclohexenos/farmacología , Células Endoteliales/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas/métodos , Limoneno , Masculino , Aceites Volátiles/farmacología , Fenilefrina/química , Fenilefrina/farmacología , Ratas , Ratas Wistar , Resinas de Plantas/química , Terpenos/química , Terpenos/farmacología , Vasodilatadores/química , Vasodilatadores/farmacología
8.
Saudi J Biol Sci ; 24(2): 355-361, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28149173

RESUMEN

Evaluations of the therapeutic potential of medicinal plants and their components have been the subject of many studies. Furthermore, the biological activities of various plant species have been reported in various pieces of literature. Hyptis martiusii Benth (Lamiaceae), popularly known as "mad balm" is commonly found in the North, Southeast, and Northeast of Brazil. Its leaves are used ethnobiologically as antiulcerogenic, antimicrobial, antitumor and as insecticide. This study aimed to analyze the chemical composition of the essential oil of H. martiusii Benth (OEHM) by GC/MS as well as its possible topical activity as an antiedematogenic. This is verified by the models of ear edema induced by single (acute edema) and multiple (chronic edema) applications of croton oil topically, and systemically verified through the model of paw edema induced by carrageenan 1%. Doses of 50, 75 and 100 mg/kg OEHM were used in all tests. Chemical analysis of the oil revealed the 1,8-cineole (34.58%) and δ-carene (21:58%) as major components present in the essential oil. On the model of ear edema, acute and chronic OEHM in all the tested doses showed no significant antiedematogenic activity (p < 0.05). The systemic model of paw edema induced by carrageenin showed that a dose of 100 mg/kg effectively reduced swelling by 55.37% in the second hour evaluation when compared to the saline group. The anti-inflammatory systemic effect can give greater bioavailability of the components present in the essential oil and your interference in cytokines and leukotriene, thromboxane and prostaglandin biosynthesis. It is therefore concluded that OEHM presents systemic antiedematogenic activity but not topical activity at these doses.

9.
Microb Pathog ; 95: 200-207, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27085299

RESUMEN

The therapeutic combinations have been increasingly used against fungal resistance. Natural products have been evaluated in combination with pharmaceutical drugs in the search for new components able to work together in order to neutralize the multiple resistance mechanisms found in yeasts from the genus Candida. The aqueous and hydroethanolic extracts from Psidium brownianum Mart ex DC. and Psidium guajava L. species were evaluated for their potential to change the effect of commercial pharmaceutical drugs against Candida albicans and Candida tropicalis strains. The tests were performed according to the broth microdilution method. Plate readings were carried out by spectrophotometry, and the data generated the cell viability curve and IC50 of the extracts against the yeasts. A chemical analysis of all the extracts was performed for detection and characterization of the secondary metabolites. The total phenols were quantified in gallic acid eq/g of extract (GAE/g) and the phenolic composition of the extracts was determined by HPLC. Fluconazole and all extracts presented high Minimum Inhibitories Concentrations (MICs). However, when associated with the extracts at sub-inhibitory concentrations (MIC/16), fluconazole had its effect potentiated. A synergistic effect was observed in the combination of fluconazole with Psidium brownianum extracts against all Candida strains. However, for Psidium guajava extracts the synergistic effect was produced mainly against the Candida albicans LM77 and Candida tropicalis INCQS 400042 strains. The IC50 values of fluconazole ranged from 19.22 to 68.1 µg/mL when it was used alone, but from 2.2 to 45.4 µg/mL in the presence of the extracts. The qualitative chemical characterization demonstrated the presence of phenols, flavonoids and tannins among the secondary metabolites. The concentration of total phenols ranged from 49.25 to 80.77 GAE/g in the P. brownianum extracts and from 68.06 to 82.18 GAE/g in the P. guajava extracts. Our results indicated that both P. brownianum and P. guajava extracts are effective on potentiating the effect of fluconazole, and therefore, these plants have the potential for development of new effective drugs for treating fungal infections.


Asunto(s)
Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candida tropicalis/efectos de los fármacos , Sinergismo Farmacológico , Fluconazol/farmacología , Extractos Vegetales/farmacología , Psidium/química , Antifúngicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Concentración 50 Inhibidora , Pruebas de Sensibilidad Microbiana , Fitoquímicos/análisis , Extractos Vegetales/aislamiento & purificación , Espectrofotometría
10.
Microb Pathog ; 95: 111-116, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27033000

RESUMEN

Medicinal plants are often the only therapeutic resource for many communities and ethnic groups. Cordia verbenacea DC., "Erva-baleeira," is one of the species of plants currently used to produce a phytotherapeutic product extracted from its leaves. The present study aimed to establish its chemical profile, antibacterial activity and resistance-modulating potential. The C. verbenacea extracts were prepared from fresh leaves using solvents as methanol and hexane. Ethyl Acetate was used for the preparation of the fraction. Phytochemical screening was carried out using HPLC-DAD for determination and quantification of the secondary metabolites present in the fractions. Antibacterial and resistance-modulation assays were performed to determine minimum inhibitory concentration (MIC) using a microdilution assay. The data were subjected to statistical analysis with two-way ANOVA and Bonferroni posttests. Results of phytochemical prospecting and HPLC analysis of the fractions were in agreement with the literature. The natural products presented moderate antibacterial activity when considering the clinical relevance of a MIC of 256 µg/mL against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, and 512 µg/mL against P. aeruginosa. However, when the fractions were combined with antibiotics we observed a synergic effect, as natural products enhanced the antibacterial effect of aminoglycosides, significantly decreasing the MIC of antibiotics at 12.5%-98.4%. We believe that the data obtained from phytochemical analysis and from antibacterial and resistance modulation assays of C. verbenacea extracts new can open perspectives in the search for new alternatives for the treatment of bacterial infections and stimulate the renewed use of antibiotics with reduced effectiveness due to resistance.


Asunto(s)
Aminoglicósidos/farmacología , Antibacterianos/farmacología , Productos Biológicos/farmacología , Cordia/química , Sinergismo Farmacológico , Fitoquímicos/farmacología , Antibacterianos/aislamiento & purificación , Productos Biológicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Fitoquímicos/análisis , Fitoquímicos/aislamiento & purificación , Hojas de la Planta/química , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
11.
Nat Prod Res ; 30(16): 1851-3, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26284428

RESUMEN

The aim of this work was to evaluate the interactions between gentamicin and the ethanol extract of the fern Lygodium venustum SW (EELV). The ethanol extract of L. venustum was obtained, the phytocompounds were identified and the EELV was assayed by the checkerboard method with gentamicin against two bacterial strains multiresistant to antibiotics. The antibiotic activity of gentamicin, when associated with the extract, was enhanced in an additive manner against both strains. The results indicated that L. venustum can be a source of secondary metabolites to be used in association with antibiotics as aminoglycosides in the antibiotic chemotherapy against resistant bacteria.


Asunto(s)
Antibacterianos/farmacología , Helechos/química , Gentamicinas/farmacología , Extractos Vegetales/farmacología , Antibacterianos/química , Evaluación Preclínica de Medicamentos/métodos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Sinergismo Farmacológico , Escherichia coli/efectos de los fármacos , Etanol/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Staphylococcus aureus/efectos de los fármacos
12.
Drug Des Devel Ther ; 9: 5965-72, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26604695

RESUMEN

BACKGROUND: The challenge of antibiotic resistance and the emergence of new infections have generated considerable interest in the exploration of natural products from plant origins as combination therapy. In this context, crude ethanolic extract (CEE), ethyl acetate fraction (EAF), and methanolic fraction (MF) from Anacardium microcarpum were tested alone or in combination with antibiotics (amikacin, gentamicin, ciprofloxacin, and imipenem) against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. METHODS: Antibiotic resistance-modifying activity was performed using the microdilution method by determining the minimal inhibitory concentration (MIC). In addition, phytochemical prospecting analyses of tested samples were carried out. RESULTS: Our results indicated that all the extracts showed low antibacterial activity against multidrug-resistant strains (MIC =512 µg/mL). However, addition of CEE, EAF, and MF to the growth medium at the subinhibitory concentration (MIC/8=64 µg/mL) significantly modulated amikacin- and gentamicin-resistant E. coli 06. CEE and EAF also demonstrated a significant (P<0.001) synergism with imipenem against S. aureus. In contrast, MF antagonized the antibacterial effect of ciprofloxacin and gentamicin against P. aeruginosa 03 and S. aureus 10, respectively. Qualitative phytochemical analysis of the extracts revealed the presence of secondary metabolites including phenols, flavonoids, xanthones, chalcones, and tannin pyrogallates. CONCLUSION: Taken together, our results suggest that A. microcarpum is a natural resource with resistance-modifying antibacterial activity that needs to be further investigated to overcome the present resistant-infection problem.


Asunto(s)
Anacardium/química , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Extractos Vegetales/farmacología , Antibacterianos/administración & dosificación , Sinergismo Farmacológico , Quimioterapia Combinada , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Pseudomonas aeruginosa/efectos de los fármacos , Metabolismo Secundario , Staphylococcus aureus/efectos de los fármacos
13.
Pharm Biol ; 53(2): 185-91, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25255929

RESUMEN

CONTEXT: Murraya paniculata (Linn) JACK (Rutaceae) is used in traditional medicine in the treatment of diabetes, inflammation, and microbial disorders. OBJECTIVE: This study determined the polyphenol composition and antimicrobial and acute toxicological activity of the hydroethanolic extract of M. paniculata leaves (EEMp). MATERIALS AND METHODS: Chemical composition was evaluated by the Folin-Ciocalteu and AlCl3 assays and by HPLC-DAD. Antibacterial and modulatory activity was determined by the microdilution method. Toxicity was assessed with a single dose of EEMp administered orally at doses of 2000 and 5000 mg/kg body weight/day in male and female Swiss mice. RESULTS: Total phenolic content of the EEMp samples varied from 66.5 to 396.8 mg gallic acid equivalent/g of extract and flavonoid content varied from 0.3 to 31.1 mg quercetin equivalent/g of extract. The principal component identified by HPLC-DAD assay was ellagic acid. The results of oral acute toxicity showed no mortality, changes in hematological parameters, or CNS and ANS toxicities in rats. Biochemical analysis showed a significant increase in glucose and glutamic oxaloacetic transaminase activity and reduction in triglycerides and cholesterol for 5000 and 2000 mg/kg doses, respectively, when compared with the control group. Histopathological evaluation showed no significant microscopic changes. EEMp showed essentially no antimicrobial activity, but when aminoglycosides were combined with EEMp their MIC was reduced. CONCLUSIONS: Significant effects were observed in the acute toxicity assay, but they had no clinical relevance. The results suggest that M. paniculata could be used as a source of natural products with antibacterial resistance-modifying activity, with lower toxicity.


Asunto(s)
Antibacterianos/aislamiento & purificación , Farmacorresistencia Bacteriana/efectos de los fármacos , Flavonoides/aislamiento & purificación , Murraya/química , Extractos Vegetales/química , Animales , Antibacterianos/farmacología , Antibacterianos/toxicidad , Brasil , Relación Dosis-Respuesta a Droga , Femenino , Flavonoides/farmacología , Flavonoides/toxicidad , Masculino , Medicina Tradicional , Pruebas de Sensibilidad Microbiana , Hojas de la Planta/química , Ratas Wistar
14.
Rev. cienc. salud (Bogotá) ; 12(3): 401-409, set.-dic. 2014. graf, tab
Artículo en Portugués | LILACS, COLNAL | ID: lil-729537

RESUMEN

Objetivo: Estudos recentes apontam a utilização de plantas na forma de sucos ou chás como fontes de agentes antioxidantes naturais que apresentam baixo risco podendo ser utilizado no auxílio do tratamento de várias doenças. Materiais e métodos: Neste contexto, avaliaram-se os potenciais antioxidantes, in vitro, dos extratos de Eugenia uniflora e Psidium sobraleanum, além de quantificar fenóis e flavonoides presentes nos extratos. Resultados: De acordo com os resultados obtidos, observou-se uma melhor atividade antioxidante para o extrato de Eugenia uniflora, para o teste de TBARS com fosfolipídio de ovo, os extratos reduziram os níveis basais no processo de peroxidação lipídica, e quando induzidos por Fe2+ o extrato de Psidium sobraleanum mostrouse mais eficiente. Conclusões: Portanto, através destes ensaios pode-se verificar que os extratos das folhas das espécies, Eugenia uniflora e Psidium sobraleanum, apresentam uma atividade antioxidante, diretamente relacionada com substâncias fenólicas produzidas a partir do seu metabolismo secundário.


Objetivo: Estudios recientes reportan la utilización de plantas en forma de zumos o té como fuente de agentes antioxidantes naturales que presentan bajo riesgo, pudiendo ser utilizados como complemento del tratamiento de diversas enfermedades. Materiales y métodos: En este contexto, se evaluarán in vitro, los potenciales antioxidantes, de los extractos de Eugenia uniflora y Psidium sobraleanum, además de cuantificar fenoles y flavonoides presentes en los extractos. Resultados: De acuerdo con los resultados obtenidos, se observó una mejor actividad antioxidante con el extracto de Eugenia uniflora, en el test de TBARS con fofolípidos de huevo, los extractos redujeron los niveles basales en el proceso de peroxidación lipídica; y cuando fue inducida con Fe+2, el extracto de Psidium sobraleanum se mostró más eficiente. Conclusiones: Por lo tanto, a través de estos ensayos se pudo comprobar que los extractos de las hojas de las especies Eugenia uniflora y Psidium sobraleanum presentan actividad antioxidante, directamente relacionada con sustancias fenólicas producidas a partir de sus metabolitos secundarios.


Objective: Evaluation of antioxidant activity has been an important issue considering its importance in human health. Recent studies show that the use of plants in the form of juices or teas as sources of natural antioxidants with low risk can be used as an aid to the treatment of various diseases. Material and Methods: Evaluation of the antioxidant potential in vitro, extracts of Eugenia uniflora and Psidium sobraleanum, as well as the quantification of phenols and flavonoids present in the extracts. Results: Findings showed a better antioxidant activity for the extract of Eugenia uniflora. In the TBARS test with egg phospholipids, extracts presented a reduction in the basal levels in the lipid peroxidation process; and when the Fe2 + extract was inducted, Psidium sobraleanum proved to be more efficient.. Conclusions: These tests proved that the extracts of leaves of the species Eugenia uniflora and Psidium sobraleanum present antioxidant activity which is directly related to phenolic substances produced in its secondary metabolism.


Asunto(s)
Humanos , Peroxidación de Lípido , Productos Biológicos , Extractos Vegetales , Psidium , Compuestos Fenólicos , Eugenia , Antioxidantes
15.
J Ethnopharmacol ; 153(2): 469-77, 2014 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-24625391

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Croton campestris A. St.-Hill., popularly known as "velame do campo", is a species native from savannah area of Northeast Brazil, which is used by traditional communities in folk medicine for a variety of health problems, especially detoxification, inflammation and gastritis. The present study investigates the possible gastric antiulcer activity of Croton campestris root extract (CCRE) and mechanisms of action underlying this effect. MATERIALS AND METHODS: Gastric lesions were induced in mice by ethanol, acidified ethanol and indomethacin. CCRE was previously administered orally in doses ranging from 50 to 750 mg/kg. Stomach lesions were measured. The involvement of Nitric Oxide (NO), prostaglandins (PGEs), ATP-dependent K+ channel and adrenergic receptor was investigated through specific inhibitors. RESULTS: CCRE produced significant antiulcer activity against absolute ethanol, acidified ethanol and indomethacin induced gastric lesions. The pretreatment with L-NAME (10 mg/kg, p.o.), an inhibitor of nitric oxide synthesis and indomethacin (10 mg/kg, s.c.), an inhibitor of prostaglandin production, reversed the antiulcer action of CCRE. CONCLUSION: Taking together, these results suggest that the antiulcer activity of CCRE is dependent of NO and prostaglandin pathways possibly due to its ability to stimulate the synthesis of NO, and activation of endogenous prostaglandin production. Therefore, the use of CCRE in traditional Brazilian medicine against gastric disorders has a scientific basis.


Asunto(s)
Croton , Modelos Animales de Enfermedad , Óxido Nítrico/metabolismo , Extractos Vegetales/uso terapéutico , Prostaglandinas/metabolismo , Úlcera Gástrica/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Ratones , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas , Sustancias Protectoras/aislamiento & purificación , Sustancias Protectoras/uso terapéutico , Úlcera Gástrica/prevención & control
16.
Pharm Biol ; 52(5): 560-5, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24251788

RESUMEN

CONTEXT: The combination of antibiotics with natural products has demonstrated promising synergistic effects in several therapeutic studies. OBJECTIVE: The aim of this study was to determine the effect of a combination of an ethanol extract of Myracrodruon urundeuva Fr. All. (Anacardiaceae) (aroeira plant) and its essential oil with six antimicrobial drugs against multiresistant strains of Staphylococcus aureus and Escherichia coli from clinical isolates. MATERIALS AND METHODS: After identification of the chemical components by GC-MS, the antibacterial activity of the natural products and antibiotics was assessed by determining the minimal inhibitory concentration (MIC) using the microdilution method and concentrations ranging 8-512 µg/mL and 0.0012-2.5 mg/mL, respectively. Assays were performed to test for a possible synergistic action between the plant products and the antimicrobials, using the extract and the oil at a sub-inhibitory concentration (128 µg/mL) and antibiotic at concentrations varying between 8 and 512 µg/mL. RESULTS: The GC-MS analysis identified the main compound as δ-carene (80.41%). The MIC of the natural products was >1024 µg/mL, except against S. aureus ATCC25923. Only the combinations of the natural products with gentamicin, amikacin and clindamycin were effective against S. aureus 358, enhancing the antibiotic activity by reducing the MIC. CONCLUSIONS: The extract from aroeira showed a higher antibacterial activity and the oil was more effective in potentiating the activity of conventional antibiotics.


Asunto(s)
Anacardiaceae/química , Antibacterianos/farmacología , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Aceites de Plantas/farmacología , Terpenos/farmacología , Antibacterianos/administración & dosificación , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Sinergismo Farmacológico , Escherichia coli/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/administración & dosificación , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Aceites de Plantas/administración & dosificación , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Terpenos/administración & dosificación , Terpenos/química , Terpenos/aislamiento & purificación
17.
Artículo en Inglés | MEDLINE | ID: mdl-23864894

RESUMEN

Croton campestris A. St.-Hill., popularly known as "velame do campo," is a species native to the savannah area of Northeast Brazil, which is used by traditional communities in folk medicine for variety of health problems, especially detoxification, inflammation, and gastritis. The hydroalcoholic extract of C. campestris leaves (HELCC) was assessed for its antiulcerogenic effect in gastric lesion models and effect on intestinal motility in mice, and possible mechanisms of action were examined. HELCC showed significant gastroprotective action in all models of gastric ulcer evaluated; the results suggest that this action probably involves the nitric oxide pathway. HELCC did not show alteration of intestinal motility in mice. It was also found that C. campestris represents a promising natural source with important biological potential, justifying some of its uses in folk medicine.

18.
J Med Food ; 16(7): 669-71, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23819641

RESUMEN

Candidiasis is the most frequent infection by opportunistic fungi such as Candida albicans, Candida tropicalis, and Candida krusei. Ethanol extract from Eugenia uniflora was assayed, for its antifungal activity, either alone or combined with four selected chemotherapeutic antimicrobial agents, including anphotericin B, mebendazole, nistatin, and metronidazole against these strains. The obtained results indicated that the association of the extract of E. uniflora to metronidazole showed a potential antifungal activity against C. tropicalis. However, no synergistic activity against the other strains was observed, as observed when the extract was associated with the other, not enhancing their antifungal activity.


Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Extractos Vegetales/farmacología , Syzygium/química , Candida/crecimiento & desarrollo , Candidiasis/microbiología , Combinación de Medicamentos , Sinergismo Farmacológico , Humanos , Pruebas de Sensibilidad Microbiana
19.
Acta toxicol. argent ; 21(1): 50-56, jun. 2013. tab
Artículo en Portugués | LILACS | ID: lil-694584

RESUMEN

. Doenças parasitárias infecciosas como leishmaniose e doença de Chagas tem se difundido nas últimas décadas a locais onde antes não se observava sua ocorrência. São consideradas negligenciadas por assolarem países pobres e serem marginalizadas farmacologicamente. O tratamento não apresenta muitas opções de fármacos e estes demonstram relevante toxicidade contribuindo para o aparecimento de diversos efeitos colaterais. A pesquisa com produtos naturais tem se mostrado uma interessante alternativa para a procura por novos fármacos. Lygodium venustum é uma samambaia cosmopolita de hábito lianescente encontrada na encosta na Chapada do Araripe, considerada por algumas populações americanas como planta medicinal para o tratamento de dermatoses, infecções, micoses e tricomoníases. Neste estudo foi avaliada sua atividade anti-parasitária contra Leishmania brasiliensis e Trypanosoma cruzi, bem como sua citotoxicidade através de ensaios n vitro. Foram testadas a fração hexânica e o extrato etanólico obtido das folhas de Lygodium venustum em diferentes concentrações. Para os testes in vitro de T. cruzi, foi utilizado o clone CL-B5 e para Leishmania brasiliensis foram utilizadas formas promastigotas. O ensaio de citotoxicidade foi realizado com linhagens de fbroblastos. L. venustum não apresentou atividade antiparasitária clinicamente relevante na forma de extrato etanólico bruto nem como fração hexânica contra Leishmania. A fração hexânica apresentou uma atividade intermediária contra T. cruzi, porém a concentração de efeito moderado possui citotoxicidade máxima tornando-se inviável para aplicação clínica. Entretanto, a citoxicicidade apresentada poderá ser útil em pesquisas sobre atividade antineoplásica em células tumorais.


Infectious and parasitic diseases like leishmaniasis and Chagas disease have spreading recent decades to places not observed before. They are considered neglected by desolating poor countries and marginalized pharmacologically. There are not many options for the treatment and these drugs have shown signifcant toxicity contributing to the appearance of several side effects. Research on natural products has been shown to be an interesting alternative to the search for new drugs. Lygodium venustum is a cosmopolitan fern with latescence habit found on the Chapada do Araripe, considered by some American popula-tions as a medicinal plant for the treatment of skin diseases, infections, fungal infections and trichomoniasis. This study evaluated its antiparasitic activity against Trypanosoma cruzi and Leishmania brasiliensis, as well as its cytotoxicity through trials in vitro. We tested the ethanolic extract and hexane fraction obtained from the leaves of L. venustum at different concentrations. For in vitro tests of T. cruzi, we used the clone CL-B5 and for L. brasiliensis we used promastigotes. The cytotoxicity assay was performed with strains of fbroblasts. L.venustum showed no antiparasitic activity clinically relevant in the form of crude ethanolic extractor as the hexane fraction against Leishmania. The hexane fraction showed an intermediate activity against T.cruzi, but the concentration of moderate effect has maximum cytotoxicity becoming unfeasible for clinical application. However, the cytotoxicity presented may be useful in research on antineoplastic activity in tumor cells.


Asunto(s)
Helechos/toxicidad , Leishmania braziliensis , Tripanocidas/análisis , Trypanosoma cruzi , Antiparasitarios/análisis
20.
Exp Parasitol ; 134(2): 178-82, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23541466

RESUMEN

The search for new therapeutic agents has been a constant for the treatment of diseases such as leishmaniasis and Chagas disease. Most drugs used have side effects, justifying the need to evaluate the cytotoxicity of the tested products for candidates to new drugs. In this study, the bioactivity of Lygodium venustum, a cosmopolitan fern of Lygodiaceae, was assessed about their leishmanicidal and trypanocidal potential. The better activity was observed using methanol fraction, with inhibition percentage of 63% and 68% for promastigotes and epimastigotes, respectively, at a concentration of 500 µg/mL. The ethyl acetate and methanol fractions demonstrated a higher cytotoxic potential. This was the first report of leishmanicidal, trypanocidal and cytotoxic activities to L. venustum.


Asunto(s)
Antiprotozoarios/farmacología , Helechos/química , Leishmania braziliensis/efectos de los fármacos , Extractos Vegetales/farmacología , Trypanosoma cruzi/efectos de los fármacos , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Fenoles/análisis , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Tripanocidas/química , Tripanocidas/aislamiento & purificación , Tripanocidas/farmacología
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