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1.
Phytochemistry ; 203: 113415, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36049527

RESUMO

The chemical composition and the antioxidant potential of Ecuadorian propolis samples (n = 19) collected in different provinces were investigated. HPLC-DAD-ESI/MSn and GC-EI-MS analysis of the methanol extracts enabled us to define six types of Ecuadorian propolis based on their secondary metabolite composition. 68 compounds were identified, 59 of which are reported for the first time in Ecuadorian propolis. The detected compounds include flavonoids, diterpenes, triterpenes, organic acid derivatives, alkylresorcinol derivatives and nemorosone. Plants belonging to genera Populus, Mangifera and Clusia seemed to be vegetable sources employed by bees to produce Ecuadorian propolis. Total phenolic content and antioxidant activity of propolis extracts were determined by the Folin-Ciocalteu assay and 2,2-diphenyl-1-picrylhydrazyl and ferric reducing/antioxidant potential assays, respectively. As expected, the variable chemical composition affected the differences in terms of antioxidant potential.


Assuntos
Diterpenos , Própole , Triterpenos , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Diterpenos/química , Equador , Flavonoides/química , Metanol , Própole/química , Triterpenos/análise
2.
Molecules ; 25(9)2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32370149

RESUMO

Ageratina havanensis (Kunth) R. M. King & H. Robinson is a species of flowering shrub in the family Asteraceae, native to the Caribbean and Texas. The aim of this work was to compare the quantitative chemical composition of extracts obtained from Ageratina havanensis in its flowering and vegetative stages with the antioxidant potential and to determine the effects on P-glycoprotein (P-gp) function. The quantitative chemical composition of the extracts was determined quantifying their major flavonoids by UPLC-ESI-MS/MS and by PCA analysis. The effects of the extracts on P-gp activity was evaluated by Rhodamine 123 assay; antioxidant properties were determined by DPPH, FRAP and inhibition of lipid peroxidation methods. The obtained results show that major flavonoids were present in higher concentrations in vegetative stage than flowering stage. In particular, the extracts obtained in the flowering season showed a significantly higher ability to sequester free radicals compared to those of the vegetative season, meanwhile, the extracts obtained during the vegetative stage showed a significant inhibitory effect against brain lipid peroxidation and a strong reductive capacity. This study also showed the inhibitory effects of all ethanolic extracts on P-gp function in 4T1 cell line; these effects were unrelated to the phenological stage. This work shows, therefore, the first evidence on: the inhibition of P-gp function, the antioxidant effects and the content of major flavonoids of Ageratina havanensis. According to the obtained results, the species Ageratina havanensis (Kunth) R. M. King & H. Robinson could be a source of new potential inhibitors of drug efflux mediated by P-gp. A special focus on all these aspects must be taking into account for future studies.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Ageratina/química , Antioxidantes/química , Antioxidantes/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Estrutura Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
3.
Naturwissenschaften ; 106(5-6): 25, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31069518

RESUMO

The main chemical composition of Sonoran propolis (SP), as well as its antiproliferative activity on cancer cells through apoptosis induction, has been reported. The chemical constitution of SP remained qualitatively similar throughout the year, whereas the antiproliferative effect on cancer cells exhibited significant differences amongst seasonal samples. The main goal of this study was to provide phytochemical and pharmacological evidence for the botanical source of SP and its antiproliferative constituents. A chemical comparative analysis of SP and plant resins of species found in the surrounding areas of the beehives was carried out by HPLC-UV-DAD, as well as by 1H NMR experiments. The antiproliferative activity on cancerous (M12.C3.F6, HeLa, A549, PC-3) and normal cell lines (L-929; ARPE-19) was assessed through MTT assays. Here, the main polyphenolic profile of SP resulted to be qualitatively similar to Populus fremontii resins (PFR). However, the antiproliferative activity of PFR on cancer cells did not consistently match that exhibited by SP throughout the year. Additionally, SP induced morphological modifications on treated cells characterised by elongation, similar to those induced by colchicine, and different to those observed with PFR treatment. These results suggest that P. fremontii is the main botanical source of SP along the year. Nevertheless, the antiproliferative constituents of SP that induce that characteristic morphological elongation on treated cells are not obtained from PFR. Moreover, the presence of kaempferol-3-methyl-ether in SP could point Ambrosia ambrosioides as a secondary plant source. In conclusion, SP is a bioactive poplar-type propolis from semi-arid zones, in which chemical compounds derived from other semi-arid plant sources than poplar contribute to its antiproliferative activity.


Assuntos
Própole/química , Própole/farmacologia , Células A549 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Clima Desértico , Células HeLa , Humanos , Populus/química
4.
J Agric Food Chem ; 66(33): 8703-8713, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30048138

RESUMO

Solanum paniculatum L. is widely used in Brazilian folk medicine for the treatment of liver and gastrointestinal disorders as well as for culinary purposes and beverage production. Fractionation of hydroalcoholic [ethanol (EtOH) 70%] tincture from S. paniculatum leaves led to the isolation of six new spirostanic saponins which included 6- O-α-l-rhamnopyranosyl-(1''→3')-ß-d-quinovopyranosyl-(22 S,23 R,25 S)-3ß,6α,23-trihydroxy-5α-spirostane (1), 6- O-ß-d-xylopyranosyl-(1''→3')-ß-d-quinovopyranosyl-(22 S,23 R,25 R)-3ß,6α,23-trihydroxy-5α-spirostane (4), 3- O-α-l-rhamnopyranosyl-(1''→3')-ß-d-quinovopyranosyl-(22 S,23 S,25 R)-3ß,6α,23-trihydroxy-5α-spirostane (5), 3- O-ß-d-xylopyranosyl-(1''→3')-ß-d-quinovopyranosyl-(22 S,23 S,25 R)-3ß,6α,23-trihydroxy-5α-spirostane (6), 6- O-α-l-rhamnopyranosyl-(1''→3')-ß-d-quinovopyranosyl-(22 S,25 S)-1ß,3ß,6α-trihydroxy-5α-spirostane (7), and 6- O-ß-d-xylopyranosyl-(1''→3')-ß-d-quinovopyranosyl-(22 S,25 S)-3ß,4ß,6α-trihydroxy-5α-spirostane (8) together with two known spirostanic saponins (2, 3). The structures of these compounds were determined by one-dimensional (1D) and two-dimensional (2D) NMR experiments in addition to high-resolution electrospray ionization mass spectrometry (HRESIMS) analyses. The 70% alcohol tincture, used as phytomedicine, exhibited promising activities against oral pathogens, including, Steptococcus sanguinis, St. oralis, St. mutans, St. mitis, and Lactobacillus casei with minimal inhibitory concentration (MIC) values ranging from 6.25 to 50 µg/mL. The saponin fraction, nonetheless, showed lower activity against all the strains tested (from 100 to >400 µg/mL).


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Doenças da Boca/microbiologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Solanum/química , Antibacterianos/isolamento & purificação , Brasil , Humanos , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Saponinas , Streptococcus/efeitos dos fármacos , Streptococcus/crescimento & desenvolvimento
5.
J Chromatogr A ; 1520: 83-90, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-28939231

RESUMO

Lippia origanoides (Verbenaceae) is an important Brazilian medicinal plant, also used for culinary purposes. Most chemical studies with this plant have been focused on its volatile composition. In this work, we combined High-Speed Counter-current Chromatography (HSCCC) and High Performance Liquid Chromatography coupled to Ultra Violet detection and High Resolution Mass Spectrometry (HPLC-UV-HRMSn) methodologies to access the non-volatile chemical composition of L. origanoides. The crude ethanol extract of L. origanoides (LOEF) was first analyzed by HPLC-UV-HRMSn and allowed the identification of 7 major compounds. Among them, eriodictyol, naringenin and pinocembrin, were determined and are phytochemical markers of this plant. However, owing to the complexity of this plant matrix, LOEF was fractionated by HSCCC (hexane-ethanol-water, 4:3:1) as a tool for preparative pre-purification, affording a flavonoid-rich fraction. A column screening with the chromatographic stationary phases ZIC-HILIC, monolithic and particulate RP18 was performed. The best column separation was achieved with a Purospher STAR RP18e, which was used for HPLC-DAD-HRMSn studies. By this approach 12 compounds were further identified in addition to the major ones identified in the raw extract. Two of them, 6,8-di-C-hexosyl-luteolin and 6,8-di-C-glucosyl-apigenin, are being reported for the first time in the family Verbenaceae. This work shows the integration of HSCCC as a preparative tool for the fractionation and purification of natural products from a complex plant extract with other analytical techniques, with the purpose of showing each technique's potential.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Lippia/química , Espectrometria de Massas , Fenóis/análise , Brasil , Fracionamento Químico , Extratos Vegetais/química , Plantas Medicinais/química
6.
Fitoterapia ; 120: 177-183, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28642199

RESUMO

Three propolis samples were collected from different regions of Ecuador (Quito, Guayaquil and Cotacachi) and their methanolic extracts were prepared. Preliminary information supplied by TLC and NMR data, allowed us to define two main types of propolis: Cotacachi propoli sample (CPS), rich in flavonoids and Quito and Guayaquil samples (QPS and GPS) containing triterpenic alcohols and acetyl triterpenes as the main constituents. Two different approaches based on RP-HPLC preparative procedure and NMR structural determination (CPS) and GC-MS analysis (QPS and GPS) were successfully used for the chemical characterization of their major compounds. All three propolis extracts were able to inhibit Leishmania amazonensis growth but propolis sample rich in flavonoids was the most active (IC50=17.1±1.7µg/mL). In the literature this is the first study on propolis from Ecuador.


Assuntos
Antiprotozoários/química , Flavonoides/química , Própole/química , Triterpenos/química , Animais , Antiprotozoários/isolamento & purificação , Células Cultivadas , Equador , Flavonoides/isolamento & purificação , Leishmania/efeitos dos fármacos , Macrófagos/parasitologia , Camundongos Endogâmicos BALB C , Triterpenos/isolamento & purificação
7.
J Chromatogr A ; 1481: 92-100, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-28027839

RESUMO

Ampelozizyphus amazonicus Ducke (Rhamnaceae), a medicinal plant used to prevent malaria, is a climbing shrub, native to the Amazonian region, with jujubogenin glycoside saponins as main compounds. The crude extract of this plant is too complex for any kind of structural identification, and HPLC separation was not sufficient to resolve this issue. Therefore, the aim of this work was to obtain saponin enriched fractions from the bark ethanol extract by countercurrent chromatography (CCC) for further isolation and identification/characterisation of the major saponins by HPLC and MS. The butanol extract was fractionated by CCC with hexane - ethyl acetate - butanol - ethanol - water (1:6:1:1:6; v/v) solvent system yielding 4 group fractions. The collected fractions were analysed by UHPLC-HRMS (ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry) and MSn. Group 1 presented mainly oleane type saponins, and group 3 showed mainly jujubogenin glycosides, keto-dammarane type triterpene saponins and saponins with C31 skeleton. Thus, CCC separated saponins from the butanol-rich extract by skeleton type. A further purification of group 3 by CCC (ethyl acetate - ethanol - water (1:0.2:1; v/v)) and HPLC-RI was performed in order to obtain these unusual aglycones in pure form.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Espectrometria de Massas/métodos , Rhamnaceae/química , Saponinas/química , Saponinas/isolamento & purificação , Butanóis/química , Glicosídeos/química , Hexanos/química , Extratos Vegetais/química , Plantas Medicinais/química , Saponinas/análise , Solventes/química , Triterpenos/química , Triterpenos/isolamento & purificação , Damaranos
8.
Biofactors ; 42(5): 475-491, 2016 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-27219221

RESUMO

Mangiferin (1,3,6,7-tetrahydroxyxanthone-C2-ß-D-glucoside) is a natural bioactive xanthonoid that can be found in many plant species, among which the mango tree (Mangifera indica L), a plant widely used in the traditional medicinal, is one of its primary sources. The use of mangiferin for cancer treatment has attracted the attention of research groups around the World. Single administration of mangiferin or in combination with known anticancer chemicals has shown the potential benefits of this molecule in lung, brain, breast, cervix, and prostate cancers, and leukemia. Mangiferin mechanisms of action against cancer cells through in vitro, ex vivo, or in vivo models are discussed besides its antioxidant and anti-inflammatory properties. Nevertheless, pharmaceutical development and, therefore, clinical trials on cancer targets are still lacking. © 2016 BioFactors, 42(5):475-491, 2016.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias/tratamento farmacológico , Xantonas/farmacologia , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apoptose , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Xantonas/uso terapêutico
9.
Food Res Int ; 90: 100-110, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29195862

RESUMO

Ampelozizyphus amazonicus Ducke is a medicinal plant used in the Amazon region to prepare a drink with tonic, immunomodulatory and adaptogenic properties. Due to the growing interest in dietary supplements with these properties and, to provide a new functional ingredient, barks from A. amazonicus were extracted. The extract was spray dried without drying adjuvants, resulting in a powder (SARF), which was characterized by its physico-chemical properties and proximate, mineral and saponin contents. The SARF saponins were characterized by ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry (HPLC-HRMSn) analysis. The SARF particles tended to have a spherical shape and a unimodal size distribution. The particles also had good rehydration characteristics and high saponin content (33%). The effect of SARF on antibody production was investigated, and we found that SARF increased the basal levels of anti-ovalbumin, anti-LPS and anti-dextran IgM antibodies, and the anti-dextran IgG antibodies in unimmunized mice. No increase in antibody titers was observed after SARF treatment in immunized mice. These results suggest that SARF could be an interesting new functional ingredient for food applications or pharmaceutical products.

10.
Chem Biol Interact ; 242: 35-44, 2015 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-26367700

RESUMO

Propolis is a resinous substance produced by honeybees (Apis mellifera) from the selective collection of exudates and bud secretions from several plants. In previous works, we reported the antiproliferative activity of Sonoran propolis (SP) on cancer cells; in addition we suggested the induction of apoptosis after treatment with SP due to the presence of morphological changes and a characteristic DNA fragmentation pattern. Herein, in this study we demonstrated that the antiproliferative effect of SP is induced through apoptosis in a B-cell lymphoma cancer cell line, M12.C3.F6, by an annexin V-FITC/Propidium iodide double labeling. This apoptotic effect of SP resulted to be mediated by modulations in the loss of mitochondrial membrane potential (ΔΨm) and through activation of caspases signaling pathway (3, 8 and 9). Afterward, in order to characterize the chemical constituents of SP that induce apoptosis in cancer cells, an HPLC-PDA-ESI-MS/MS method followed by a preparative isolation procedure and NMR spectroscopy analysis have been used. Eighteen flavonoids, commonly described in propolis from temperate regions, were characterized. Chrysin, pinocembrin, pinobanksin and its ester derivatives are the main constituents of SP and some of them have never been reported in SP. In addition, two esters of pinobanksin (8 and 13) are described by first time in propolis samples in general. The antiproliferative activity on M12.C3.F6 cells through apoptosis induction was exhibited by pinobanksin (4), pinobanksin-3-O-propanoate (14), pinobanksin-3-O-butyrate (16), pinobanksin-3-O-pentanoate (17), and the already reported galangin (11), chrysin (9) and CAPE. To our knowledge this is the first report of bioactivity of pinobanksin and some of its ester derivatives as apoptosis inducers. Further studies are needed to advance in the understanding of the molecular basis of apoptosis induction by SP and its constituents, as well as the structure-activity relationship of them.


Assuntos
Apoptose/efeitos dos fármacos , Flavanonas/farmacologia , Linfoma de Células B/tratamento farmacológico , Própole/química , Animais , Caspases/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ésteres/química , Flavanonas/química , Linfoma de Células B/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Estrutura Molecular , Própole/análise , Espectrometria de Massas por Ionização por Electrospray
11.
Nat Prod Commun ; 8(9): 1237-40, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24273855

RESUMO

The genus Garcinia is a source of a large variety of organic compounds including biflavonoids, acylphloroglucinols and xanthones mainly, but few data are available about the chemical composition of Cuban species. The aim of this investigation was to identify the main constituents of G. bakeriana Urb., a rare Cuban endemic plant. A new biflavonoid, 4'''-O-methyl-I3,II8-biapigenin (1), together with 9 known compounds, namely, the biflavonoids amentoflavone (2), 4'''-O-methylamentoflavone (3), 4'-O-methylcupressuflavone (4), GB-2a (5), volkensiflavone (6), 6"-(2-hydroxy-3-methyl-3-butenyl)-amentoflavone (7), I3,II8-biapigenin (8), and GB-1a (9), and the xanthone norathyriol (10), were isolated from the leaves of this species. All the structures were elucidated by spectroscopic methods including 1D and 2D NMR experiments, as well as ESIMS analysis. These results showed that the isolated biflavonoids possess a C-C interflavonoid linkage between the apigenin units or its derivatives.


Assuntos
Biflavonoides/isolamento & purificação , Flavonoides/isolamento & purificação , Garcinia/química , Biflavonoides/química , Flavonoides/química , Estrutura Molecular , Folhas de Planta/química
12.
Biomed Res Int ; 2013: 451679, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555087

RESUMO

Ampelozizyphus amazonicus is used in the treatment and prevention of malaria. The effect of an aqueous extract from this plant (SART) on the immune response was investigated by measuring immunoglobulin production induced by immunization with the antigen TNP-Ficoll in Plasmodium chabaudi-infected mice. SART treatment increased antigen-specific IgM and IgG levels in TNP-Ficoll-immunized mice. The B cell response during malarial infection was also modified by SART. There was an increase in total serum IgM and IgG and a decrease in the percentage of splenic plasma cells (CD138+ cells) in P. chabaudi-infected, SART-treated animals. SART (1, 3 or 10 mg/kg, p.o.) and the reference drug dexamethasone (5 mg/kg) were also tested in carrageenan-induced leukocyte migration to the subcutaneous air pouch (SAP). All SART doses significantly reduced leukocyte migration into the SAP. The protein concentration resulting from extravasation into the peritoneum was also significantly reduced. Our data indicate that SART possesses immunomodulatory properties, inducing an in vivo modification of the B lymphocyte response and anti-inflammatory properties, which are partly due to a reduction in cell migration and are most likely due to an inhibition of the production of inflammatory mediators. Preliminary HPLC-ESI-MS/MS analysis of SART shows a complex saponin profile with deprotonated molecule [M-H](-) ions in the range of m/z 800-1000.


Assuntos
Imunidade Inata/efeitos dos fármacos , Malária/tratamento farmacológico , Extratos Vegetais/farmacologia , Plasmodium chabaudi/imunologia , Rhamnaceae/química , Animais , Antígenos/imunologia , Linfócitos B/efeitos dos fármacos , Humanos , Imunização , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Malária/imunologia , Malária/parasitologia , Camundongos , Casca de Planta/química , Extratos Vegetais/química , Plasmodium chabaudi/patogenicidade
13.
J Pharm Biomed Anal ; 76: 157-63, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23333683

RESUMO

Pyranochromanone acids isolated from Calophyllum species have shown a variety of biological potentialities including antioxidant, antiulcer, anticancer and anti-Helicobacter pylori activities. These compounds seem to be the main constituents of Cuban Calophyllum species together xanthones and biflavonoids. Recently, the pyranochromanone acids calophyllic acid, isocalophyllic acid, apetalic acid, calolongic acid, isoapetalic acid, pinetoric acid I, pinetoric acid II, were isolated from Calophyllum pinetorum, a Cuban endemic species. The objective of the present work was the development of a rapid and efficient HPLC-DAD-MS method for fast screening of pyranochromanones in the leaves and resins of different endemic Calophyllum spp of Cuba, without clean-up procedures. For this purpose, a generalized fragmentation pathway was proposed and used to characterize, by HPLC-DAD-MS, the pyranochromanone acids in leaves and resins of different Calophyllum species. The developed method enables to detect also minor compounds in Calophyllum spp. The structures proposed by MS data for these compounds were unambiguous confirmed by 1D and 2D-NMR analysis and three new pyranochromanone acids, isocalolongic acid, pinetoric acid III and isopinetoric acid III, were reported here for the first time.


Assuntos
Calophyllum/química , Cromatografia Líquida de Alta Pressão/métodos , Cromonas/isolamento & purificação , Espectrometria de Massas/métodos , Cuba , Folhas de Planta , Resinas Vegetais , Fatores de Tempo
14.
J Agric Food Chem ; 60(42): 10540-5, 2012 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23004023

RESUMO

Chemical investigation of a propolis sample collected in Honduras has led to the isolation of the new (E,Z)-cinnamyl cinnamate (2) together with 14 known compounds: 6 cinnamic ester derivatives, 2 flavanones, 1 chalcone, 2 triterpenes, and 3 aromatic acids. Structural determination was accomplished by spectroscopic analysis, particularly two-dimensional (2D) nuclear magnetic resonance (NMR) and electrospray ionization-tandem mass spectrometry (ESI-MS/MS) techniques. Futhermore, we checked the ability of the propolis extract and the most representative compounds of each class (1, 5, 8, and 10) to inhibit the activity of Pdr5p, a protein responsible for a multidrug resistance phenotype in yeast. The present study appears to be the first report on Honduras propolis. Isolated cinnamic ester derivatives indicated the possible relation between Honduras propolis and the genus Liquidambar .


Assuntos
Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Própole/química , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Saccharomyces cerevisiae/metabolismo , Honduras , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
16.
Rev. bras. farmacogn ; 21(5): 901-907, Sept.-Oct. 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-600966

RESUMO

Multidrug resistance of cancer cells and pathogenic microorganisms leading to the treatment failure of some forms of cancer or life-threatening bacterial or fungal infections is often caused by the overexpression of multidrug efflux pumps belonging to the ATP-binding cassette transporters superfamily. The multidrug resistance of fungal cells often involves the overexpression of efflux pumps belonging to the pleiotropic drug resistance (PDR) family of ABC transporters. Possibly the best-studied fungal PDR transporter is the multidrug resistance transporter Pdr5p of Saccharomyces cerevisiae. Some research groups have been searching for new inhibitors of these efflux pumps in order to alleviate resistance. Natural products are a great source for the discovery of new compounds with biological activity. Propolis is a complex resinous material collected by honeybees from exudates and buds of certain plant sources and this material is thought to serve as a defense substance for bee hives. Propolis is widely used in traditional medicine and is reported to have a broad spectrum of pharmacological properties. Literature reported some biological functionalities of propolis, such as antibacterial, antiviral, fungicidal, anti-inflammatory and anti-carcinogenic activities. The chemical composition of propolis is qualitatively and quantitatively variable. Components isolated from methanolic extract of red Brazilian propolis (Alagoas, Northeast of Brazil) are isoflavonoids (including pterocarpans, isoflavans, isoflavones), flavanones and polyprenylated benzophenones. In this work we demonstrated the effects of five different isolated compounds on the ATPase activity of Pdr5p. Out of all five substances tested, only BRP-1 was able to completely abolish the enzymatic activity while others worked as positive modulators of the enzyme activity. BRP-1also inhibited the efflux of Rhodamine 6G from yeast cells overexpressing Pdr5p. Taken together, these results demonstrate that Brazilian propolis could be a source of promising compounds that can alleviate the MDR phenomenon, particularly in some fungi, where it could be used as an adjuvant for the treatment with azoles.

17.
Rev. bras. farmacogn ; 21(5): 884-888, Sept.-Oct. 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-600980

RESUMO

Wendtia calycina (Griseb.) Griseb., Vivianiaceae, is a Paraguayan herbaceous plant commonly known as burrito. Our previous study indicated that burrito leaves are a very good source of phenylpropanoid glycosides, principally verbascoside. From W. calycina leaves, a standardized, water-soluble extract rich in phenylpropanoid glycosides (WSE) has been developed on an industrial scale to be used as a food supplement, cosmetic, phytomedicine, and ingredient of different formulations. In this study, we investigated the effect of the WSE on human platelet aggregation in vitro induced by adenosine diphosphate (ADP), epinephrine (EPN), collagen (COL) or arachidonic acid (AA). WSE, concentration-dependently, inhibited ADP and EP-induced human platelet aggregation (IC50 were 0.82±0.15 mg/mL and 0.41±0.02 mg/mL, respectively). It did not inhibit collagen-induced platelet aggregation, thus suggesting a selectivity for the ADP-induced platelet activation pathways.

18.
Nat Prod Commun ; 6(7): 957-60, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21834232

RESUMO

A new phenolic derivative, 4-methoxyphenol 1-O-beta-D-apiofuranosyl-(1 --> 6)-O-beta-D-glucopyranoside (1), has been identified together with uncommon 3,4-dimethoxyphenol 1-O-beta-D-apiofuranosyl-(1 --> 6)-O-beta-D-glucopyranoside (2) and 3-hydroxy, 4-methoxyphenol 1-O-beta-D-apiofuranosyl-(1 --> 6)-O-beta-D-glucopyranoside (3) from the leaves of Martinella obovata (Kunth) Bureau & K. Schum., an Honduran species used in folk medicine for the treatment of eyes diseases. Verbascoside, isoverbascoside, leucoceptoside A, vitexin, isovitexin, luteolin 8-C-beta-D-glucopiranoside and spireoside were also found. All structures were elucidated on the basis of mass spectrometry and 2D NMR techniques.


Assuntos
Bignoniaceae/química , Glucosídeos/isolamento & purificação , Glucosídeos/química , Honduras , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray
19.
Nat Prod Commun ; 6(7): 973-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21834236

RESUMO

In this paper we analyzed the antiprotozoal effects of eighteen Cuban propolis extracts (brown, red and yellow type) collected in different geographic areas, using Leishmania amazonensis (as a model of intracellular protozoa) and Trichomonas vaginalis (as a model of extracellular protozoa). All evaluated propolis extracts caused inhibitory effect on intracellular amastigotes of L. amazonensis. However, cytotoxicity on peritoneal macrophages from BALB/c mice was observed. Only five samples decreased the viability of T. vaginalis trophozoites at concentrations lower than 10 microg/mL. No correlation between the type of propolis and antiprotozoal activity was found. Cuban propolis extracts demonstrated activity against both intracellular and extracellular protozoa model, as well as the potentialities of propolis as a natural source to obtain new antiprotozoal agents.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Própole/farmacologia , Trichomonas vaginalis/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Cuba , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Parasitária , Própole/toxicidade
20.
J Agric Food Chem ; 59(12): 6484-91, 2011 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-21598949

RESUMO

Chemical composition of propolis depends on the specificity of the local flora at the site of collection and thus on the geographic and climatic characteristics of this place. This paper describes a comparative analysis of Cuban red propolis (CRP), Brazilian red propolis (BRP), and Dalbergia ecastophyllum exudates (DEE) by high-performance liquid chromatography with diode-array detection and tandem mass spectrometry. The aim of this study was to investigate the overall chemical profile and the botanical origin of red propolis and to suggest similarities and differences between samples collected in different tropical regions. Isoliquiritigenin (1), liquiritigenin and naringenin (2 and 17), isoflavones (3-4 and 16), isoflavans (5-7 and 18), and pterocarpans (8-13) were detected in CRP, BRP, and DEE, whereas polyisoprenylated benzophenones (PPBs) guttiferone E/xanthochymol (14a,b) and oblongifolin A (15) were detected only in BRP. Pigments responsible for the red color of DEE and red propolis were also identified as two C30 isoflavans, the new retusapurpurin B (19) and retusapurpurin A (20). PPBs and pigments were isolated and unambiguously characterized by 1D and 2D NMR analysis. These results show that red propolis samples from different tropical zones have a similar chemical composition. DEE is the main red propolis source, but the presence of PPBs in BRP suggests the contribution of different botanical sources for Brazilian samples. This chemical information is important for quality control of red propolis and its commercial products and for biological study.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/análise , Própole/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Brasil , Cromatografia Líquida de Alta Pressão/instrumentação , Cuba , Extratos Vegetais/normas , Própole/normas , Controle de Qualidade , Espectrometria de Massas em Tandem/métodos
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