988 resultados para BRAZILIAN GREEN PROPOLIS


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Propolis is a hive product containing chiefly beeswax and plant-derived substances such as resin and volatile compounds. Propolis has been used in various parts of the world as an antiseptic and wound healer since ancient times, and interest in the product has recently increased. Considering the lack of data concerning the in vivo mutagenicity of green propolis, the capacity of this natural product to cause damage to the DNA was evaluated, using the alkaline single-cell gel electrophoresis (SCGE) and micronucleus test, in the peripheral blood cells of mice. The doses tested by gavage were 1000, 1500 and 2000 mg/kg. Micronucleus and SCGE assays showed that green propolis caused an increase in the damage to DNA in the peripheral blood cells of mice. The polychromatic: normochromatic erythrocytes ratio was not statistically different from the negative control. Considering the doses and the results obtained in this study, the acute consumption of green propolis produced some mutagenic effects on the blood cells of mice. (C) 2008 Elsevier Ltd. All rights reserved.

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Aim of the study: In a previous study, our group described the gastric protective effect of the hydroalcoholic extract of Brazilian green propolis. The main compounds found in Brazilian green propolis include phenolic acids, such as: caffeic, ferulic, p-coumaric and cinnamic acids. This study was therefore carried out to evaluate the antiulcerogenic property of the main phenolic acids found in Brazilian Green Propolis.Material and methods: The anti-ulcer assays were performed using the following protocols: nonsteroidal-antinflammatory drug (NSAID)-induced ulcer, ethanol-induced ulcer, and stress-induced ulcer. The effects of the phenolic acids on gastric content volume, pH and total acidity, using the pylorus ligated model, were also evaluated.Results: It was observed that treatment using doses of 50 and 250 mg/kg of caffeic, ferulic, p-coumaric and cinnamic acids and positive controls (omeprazol or cimetidine) significantly diminished the lesion index, the total area of the lesion and the percentage of lesion in comparison with the negative control groups. In addition, the percentage of ulcer inhibition was significantly higher in the groups treated with the different phenolic acids, cimetidine or omeprazol, in all the protocols used, compared with the negative control groups. In the model to determine gastric secretion, using ligated pylorus, treatment with phenolic acids and cimetidine reduced the volume of gastricjuice and total acidity and significantly increased the gastric pH (p < 0.05), compared with the control group, with the exception of the group treated with 50 mg/kg of p-coumaric acid, in which no significant difference was observed, compared with the control. In relation to the acute toxicity, none sign of toxicity was observed when phenolic acids, used in this study, were administered for rats in dose of 2000 mg/kg.Conclusions: In conclusion, the results of this study show that caffeic, ferulic, p-coumaric and cinnamic acids display antiulcer activity. (c) 2008 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Propolis effect on the growth and apoptosis of human lung adenocarcinoma (A549 cells) was investigated as well as its mechanisms. Cells were incubated with propolis for 72 h, and 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays were employed to assess cell viability and the inhibitory concentration (IC). Apoptosis was detected by Acridine Orange/Ethidium Bromide and 4',6-diamidino-2-phenylindole staining after 24 and 48 h of incubation with ¼ IC50 of propolis by testing the mitochondrial membrane potential (ΔΨm) and the expression of apoptosis-related genes (p53, Caspase-3, Bax, Bcl-2, Bcl-XL , Noxa, Puma and p21) by reverse transcription polymerase chain reaction. Propolis displayed antiproliferative and cytotoxic effects on A549 cells in a dose- and time-dependent manner, but it did not suppress the growth of normal Vero cells. An enhanced apoptosis was seen in A549 propolis-treated cells after 48 h compared with the control cells. Propolis decreased mitochondrial membrane potential by overexpression of pro-apoptotic genes (Bax and Noxa) and reduction of the antiapoptotic gene Bcl-XL . The expression level of other genes remained unchanged (p53, Caspse-3 and Bax), whereas p21 expression was increased. Propolis induced caspase-independent apoptosis through a p53-independent mitochondrial pathway, and cell cycle arrest by upregulation of p21. Although propolis induces apoptosis mainly by p53-independent manner, it may be induced by another pathway, and new insights may arise for preventing or treating lung cancer.

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Baccharis dracunculifolia DC (Asteraceae) is the main botanical source used by honeybees to produce Brazilian green propolis whose hepatoprotective properties have been already described. In this work we investigated the protective effects of the glycolic extract of B. dracunculifolia (GEBd) against oxidative stress in isolated rat liver mitochondria (RLM). The GEBd was prepared by fractionated percolation using propylene glycol as solvent. The total phenols and flavonoids, which are substances with recognized antioxidant action, were quantified in GEBd and the phytochemical analysis was carried out by HPLC. GEBd exhibited significant scavenger activity towards DPPH radicals and superoxide anions in a concentration-dependent manner, and also a Fe 2+ chelating activity. GEBd decreased the basal H 2O 2 generation and the Fe 2+- or t-BuOOH-induced ROS production in isolated mitochondria. Lipid oxidation of mitochondrial membranes, protein thiol groups and GSH oxidation were also prevented by GEBd. This shows that B. dracunculifolia exhibit potent antioxidant activity protecting liver mitochondria against oxidative damage and such action probably contribute to the antioxidant and hepatoprotective effects of green propolis. © 2011 Elsevier Ltd.

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BACKGROUND: Chloroform, ethyl acetate and methanol extracts of a sample of red propolis from the state of Alagoas (northeast Brazil) were analyzed by gas chromatography-mass spectrometry and high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Antimicrobial and antioxidant activities were also obtained. RESULTS: The propolis sample contained low content of narigenin-8-C-hexoside, this being the first report of a C-glycoside in propolis. The main constituent found was characterized as 3,4,2`,3`-tetrahydroxychalcone. Other important constituents were the chalcone isoliquiritigenin, the isoflavans (3S)-vestitol, (3S)-7-O-methylvestitol, the pterocarpan medicarpin, the phenylpropenes trans-anethol, methyl eugenol, elimicin, methoxyeugenol and cis-asarone, and the triterpenic alcohols lupeol and alpha- and beta- amyrins. The methanol extract exhibited high antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl and beta-carotene/linoleic acid assay methods, and antimicrobial activity toward Gram-positive and Gram-negative bacteria. CONCLUSION: Structures are suggested for new substances never before seen in any kind of propolis. This is the first report of 3,4,2`,3`-tetrahydroxychalcone and a flavone C-glycoside in a propolis sample. (C) 2011 Society of Chemical Industry

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Tetradifon, a potentially carcinogenic and mutagenic pesticide, can contribute to environmental and human contamination when applied to green bell pepper crops. In this context, in this work, a reliable and sensitive method for determination of tetradifon in Brazilian green bell pepper samples involving a differential pulse voltammetry (DPV) technique on a glassy carbon electrode is proposed. The electrochemical behavior of tetradifon as followed by cyclic voltammetry (CV) suggests that its reduction occurs via an irreversible five–electron transfer vs. Ag|AgCl, KCl 3 M reference electrode. Very well–resolved diffusion controlled voltammetric peaks have been obtained in a supporting electrolyte solution composed of a mixture of 40% dimethylformamide (DMF), 30% methanol, and 30% NaOH 0.3 mol L−1 at −1.43, −1.57, −1.73, −1.88, and −2.05 V. The proposed DPV method has a good linear response in the 3.00 – 10.0 μmol L−1 range, with a limit of detection (L.O.D) of 0.756 μmol L−1 and 0.831 μmol L−1 in the absence and in the presence of the matrix, respectively. Moreover, improved L.O.D results (0.607 μmol L−1) have been achieved in the absence of DMF from the supporting electrolyte solution. Recovery has been evaluated in five commercial green bell pepper samples, and recovery percentages ranging from 91.0 to 109 have been obtained for tetradifon determinations. The proposed voltammetric method has also been tested for reproducibility, repeatability, and potential interferents, and the results obtained for these three analytical parameters are satisfactory for electroanalytical purposes.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Tetradifon, a potentially carcinogenic and mutagenic pesticide, can contribute to environmental and human contamination when applied to green bell pepper crops. In this context, in this work, a reliable and sensitive method for determination of tetradifon in Brazilian green bell pepper samples involving a differential pulse voltammetry (DPV) technique on a glassy carbon electrode is proposed. The electrochemical behavior of tetradifon as followed by cyclic voltammetry (CV) suggests that its reduction occurs via an irreversible five-electron transfer vs. Ag vertical bar AgCl, KCl 3 M reference electrode. Very well-resolved diffusion controlled voltammetric peaks have been obtained in a supporting electrolyte solution composed of a mixture of 40% dimethylformamide (DMF), 30% methanol, and 30% NaOH 0.3 mol L-1 at -1.43, -1.57, -1.73, -1.88, and -2.05 V. The proposed DPV method has a good linear response in the 3.00 - 10.0 mu mol L-1 range, with a limit of detection (L.O.D) of 0.756 mu mol L-1 and 0.831 mu mol L-1 in the absence and in the presence of the matrix, respectively. Moreover, improved L.O.D results (0.607 mu mol L-1) have been achieved in the absence of DMF from the supporting electrolyte solution. Recovery has been evaluated in five commercial green bell pepper samples, and recovery percentages ranging from 91.0 to 109 have been obtained for tetradifon determinations. The proposed voltammetric method has also been tested for reproducibility, repeatability, and potential interferents, and the results obtained for these three analytical parameters are satisfactory for electroanalytical purposes. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.024207jes] All rights reserved.

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Propolis is a polyphenol-rich resinous substance extensively used to improve health and prevent diseases. The effects of polyphenols from different sources of propolis on atherosclerotic lesions and inflammatory and angiogenic factors were investigated in LDL receptor gene (LDLr-/-) knockout mice. The animals received a cholesterol-enriched diet to induce the initial atherosclerotic lesions (IALs) or advanced atherosclerotic lesions (AALs). The IAL or AAL animals were divided into three groups, each receiving polyphenols from either the green, red or brown propolis (250 mg/kg per day) by gavage. After 4 weeks of polyphenol treatment, the animals were sacrificed and their blood was collected for lipid profile analysis. The atheromatous lesions at the aortic root were also analyzed for gene expression of inflammatory and angiogenic factors by quantitative real-time polymerase chain reaction and immunohistochemistry. All three polyphenol extracts improved the lipid profile and decreased the atherosclerotic lesion area in IAL animals. However, only polyphenols from the red propolis induced favorable changes in the lipid profiles and reduced the lesion areas in AAL mice. In IAL groups. VCAM, MCP-1, FGF, PDGF, VEGF, PECAM and MMP-9 gene expression was down-regulated, while the metalloproteinase inhibitor TIMP-1 gene was up-regulated by all polyphenol extracts. In contrast, for advanced lesions, only the polyphenols from red propolis induced the down-regulation of CD36 and the up-regulation of HO-1 and TIMP-1 when compared to polyphenols from the other two types of propolis. In conclusion, polyphenols from propolis, particularly red propolis, are able to reduce atherosclerotic lesions through mechanisms including the modulation of inflammatory and angiogenic factors. (C) 2012 Elsevier Inc. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Baccharis dracunculifolia D.C. (Asteraceae), a shrub which grows wild in Brazil, is the main botanical source of Brazilian green propolis. Since Brazilian propolis shows an immunomodulatory activity, the goal of this work was to evaluate the action of B. dracunculifolia extracts and some of its isolated compounds on reactive oxygen intermediate (H2O2) production by macrophages obtained from male BALB/c mice. The results showed that the leaf (Bd-L) (25, 50, and 100 mu g mL(-1)), leaf rinse (Bd-LR) (25 mu g mL(-1)), and the root (Bd-R) (25 mu g mL(-1)) extracts enhanced H2O2 release by macrophages. A phytochemical study of the root and leaves of B. dracunculifolia was carried out. The chromatographic fractionation of Bd-R, using several techniques, afforded the isolation of baccharis oxide (1), friedelanol (2), viscidone (11), 11-hydroxy-10,11-dihydro-euparin (12), and 6-hydroxy-tremetona (13), while Bd-LR gave the following isolated compounds: baccharis oxide (1), friedelanol (2), isosakuranetin (3), aromadendrin-4'-methyl ether (4), dihydrocumaric acid (5), baccharin (6), hautriwaic acid lactone (7), hautriwaic acid acetate (8), drupanin (9), and cumaric acid (10). Among the isolated compounds, baccharis oxide (1) and friedelanol (2) increased H2O2 production at a concentration of 1001,M. This is the first time that the presence of compounds 7, 8, 12, and 13 in B. dracunculifolia has been reported. Based on these results it is suggested that the crude extracts and some isolated compounds from B. dracunculifolia display an immunomodulatory action.