1000 resultados para Sousa


Relevância:

10.00% 10.00%

Publicador:

Resumo:

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 Ireland Ltd. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Brazilian green propolis, which is used in food and beverages to improve health and to prevent diseases, demostrates antioxidant, antimutagenic, and antimicrobial activities. Most biological activities are thought to be related to the high levels of drupanin, artepillin C, and baccharin, which are compounds also present in Baccharis dracunculifolia D.C. (Asteraceae). Since propolis chemical composition depends on the region and the period of collection, as well as its plant origin, the effect of seasonal variation on the both content of prenylated p-coumaric acids and in vitro antimicrobial activity of Brazilian propolis from four different sites, was performed. The results showed that MIC values ranged from 100 to 300 mu g/mL against both Staphylococcus aureus and Kocuria rhizophila, while none of the propolis samples was active against Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. HPLC analysis showed that the content of drupanin, artepillin C, and baccharin varied throughout the year, as well as among the different study sites. Also, it is suggested that Baccharis dracunculifolia is the main botanical source of Brazilian propolis in sites I and 2, while in sites 3 and 4, other plant species are also used by bees to produce propolis. All the evaluated propolis samples exhibited similar antibacterial activity, but different contents of prenylated p-coumaric acids throughout the year.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Baccharis dracunculifolia De Candole (Asteraceae), a native plant from the Brazilian ""cerrado"", is widely used in folk medicine as an anti-inflammatory agent and for the treatment of gastrointestinal diseases. B. dracunculifolia has been described as the most important plant source of propolis in southeastern Brazil, which is called green propolis due to its color. The aim of the present study was to evaluate the mutagenic and antimutagenic effects of the ethyl acetate extract of B. dracunculifolia leaves (Bd-EAE) on Chinese hamster ovary cells. On one hand, the results showed a significant increase in the frequencies of chromosome aberrations at the highest Bd-EAE concentration tested (100 mu g/mL). On the other hand, the lowest Bd-EAE concentration tested (12.5 mu/mL) significantly reduced the chromosome damage induced by the chemotherapeutic agent doxorubicin. The present results indicate that Bd-EAE has the characteristics of a so-called Janus compound, that is, Bd-EAE is mutagenic at higher concentrations, whereas it displays a chemopreventive effect on doxorubicin-induced mutagenicity at lower concentrations. The constituents of B. dracunculifolia responsible for its mutagenic and antimutagenic effects are probably flavonoids and phenylpropanoids, since these compounds can act either as pro-oxidants or as free radical scavengers depending on their concentration.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study aimed to evaluate the chemical composition of Baccharis dracunculifolia essential oil and the water soluble oil obtained by steam distillation that were analyzed by GC and GUMS. in the first hour of distillation, B. dracunculifolia aerial parts yielded 0.08% oil and in the second hour, 0.27%. The oil recovered from the distillate water yielded 0.18 g/L in the first hour and 0.44 g/L in the second hour of distillation. The main volatile compounds identified in the distillate water were aromatic compounds and sesquiterpene alcohols.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Baccharis dracunculifolia D. C. (Asteraceae) is the most important plant source of the Brazilian green propolis. Since propolis is known for its antimicrobial activity, the aim of this work was to evaluate the showed that the leaves extract of B. dracunculifolia (BdE) presents antifungal and antibacterial activities, especially against Candida krusei and Cryptococcus neoformans, for which the BdE showed IC50 values of 65 mu g mL(-1) and 40 mu g mL(-1), respectively In comparison to the BdE, it was observed that the green propolis extract (GPE) showed better antimicrobial activity, displaying an IC50 value of 9 mu g mL(-1) against C krusei. Also, a phytochemical study of the BdE was carried out, affording the isolation of ursolic acid (1), 2 alpha-hydroxy-ursolic acid (2), isosakuranetin (3), aromadendrin-4`-methylether (4), baccharin (5), viscidone (6), hautriwaic acid lactone (7), and the clerodane diterpene 8. This is the first time that the presence of compounds 1, 2, and 8 in B. dracunculifolia has been reported. Among the isolated compounds, 1 and 2 showed antibacterial activity against methicillin-resistant Staphylococcus aureus, displaying IC50 values of 65 mu g mL(-1) and 40 mu g mL(-1), respectively. 3 was active against C neoformans, showing an IC50 value of 15 mu g mL(-1) and a MIC value of 40 mu g mL(-1), while compounds 4-8 were inactive against all tested microorganisms. The results showed that the BdE, similar to the GPE, displays antimicrobial activity, which may be related to the effect of several compounds present in the crude extract.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Copaifera species (Leguminoseae) are popularly known as ""copaiba"" or ""copaiva"". The oleoresins obtained from the trunk of these species have been extensively used in folk medicine and are commercialized in Brazil as crude oil and in several pharmaceutical and cosmetic products. This work reports a complete validated method for the quantification of beta-caryophyllene, alpha-copaene, and alpha-humulene in distinct copaiba oleoresins available commercially. Thus, essential oil samples (100 mu L) were dissolved in 20 mL of hexanes containing internal standard (1,2,4,5-tetramethylbenzene, 3.0 mM) in a 25 mL glass flask. A 1 mu L aliquot was injected into the GC-FID system. A fused-silica capillary column HP-5, coated with 5% phenylmethylsiloxane was used for this study. The developed method gave a good detection response with linearity in the range of 0.10-18.74 mM. Limits of detection and quantitation variety ranged between 0.003 and 0.091 mM. beta-Caryophyllene, alpha-copaene, and alpha-humulene were recovered in a range from 74.71% to 88.31%, displaying RSD lower than 10% and relative errors between -11.69% and -25.30%. Therefore, this method could be considered as an analytical tool for the quality control of different Copaifera oil samples and its products in both cosmetic and pharmaceutical companies. (C) 2010 Elsevier B.V. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In the present work, the anticariogenic activities of nine labdane type-diterpenes and four sesquiterpenes were investigated. Among these metabolites, (-)-copalic acid (CA) was the most active compound displaying MIC values very promising (ranging from 2.0 to 6.0 mu g/mL) against the main microorganisms responsible for dental caries: Streptococcus salivarius, S. sobrinus, S. mutans, S. mitis, S. sanguinis and Lactobacillus casei. Time kill assays performed with CA against the primary causative agent (S. mutans) revealed that, in the first 12 h, this compound only inhibits the growth of the inoculum (bacteriostatic effect). However, its bactericidal effect is clearly noted thereafter (between 12 and 24 h). Also, CA did not show a synergistic effect when combined with the anticariogenic gold standard (chlorhexidine, CHD) in the checkerboard assays against S. mutans. In conclusion, the results points out CA as an important metabolite in the search for new effective anticariogenic agents. Copyright (C) 2010 John Wiley & Sons, Ltd.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The reactive oxygen species (ROS) produced by neutrophils are involved in the pathogenesis of several diseases, for which the intake of antioxidants could benefit patients either as a prophylactic or therapeutic treatment. Propolis is among the known antioxidants, and its chemical composition may vary under the influence of seasonality, which may interfere in its biological properties. This work evaluates the role of seasonality on the production of some important compounds of propolis samples produced monthly from November 2001 through October 2002 as well as the effect of these samples on the oxidative metabolism of stimulated neutrophils, by using both luminol and lucigenin to produce chemiluminescence (CLlum and CLluc, respectively). The cytotoxicity of the most active extracts to neutrophils was also investigated. The inhibitory effect of the propolis samples varied significantly during the studied period for both assays (3.4 +/- 1.1 to 16.0 +/- 1.1 mu g/mL for CLlum and 6.2 +/- 2.0 to 30.0 +/- 5.0 mu g/mL for CLluc), which was also observed in the quantitative profile of the main analyzed compounds (aromadendrin-4`-methyl ether, artepillin C, and baccharin). This effect started to become more prominent during the fall and, among all the studied extracts, the one obtained in May displayed the highest inhibitory effect on CL production (3.4 +/- 1.1 mu g/mL for alum and 6.2 +/- 2.0 mu g/mL for CLluc). The HPLC qualitative profiles of the extracts of propolis samples were quite similar, but there was a huge variation in terms of quantitative profile. It seems that aromadendrin-4`-methyl ether and baccharin play an essential role in the antioxidant activity, while artepillin C is not very important for this effect. The extracts presenting the highest antioxidant activity were produced in May, June, and August, and they did not display cytotoxicity at 25 mu g/mL; quercetin, used as control, was not toxic to neutrophils at 8.5 mu g/mL (C) 2010 Elsevier B.V. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Aim of the study: The aerial parts of Baccharis dracunculifolia D.C., popularly known as ""alecrim do campo"" are used in folk medicine as anti-inflammatory. The aim of the present study was to evaluate the anti-inflammatory and antinociceptive activities of the crude hydroalcoholic extract obtained from leaves of Baccharis dracunculifolia (BdE), which have not been reported. Matetials and methods: BdE was analyzed by HPLC and in vivo evaluated (doses ranging from 50 to 400 mg/kg, p.o.) by using the acetic acid-induced abdominal constrictions, paw oedema induced by carrageenan or histamine, overt nociception models using capsaicin, glutamate or phorbol myristate acetate (PMA), formalin-induced nociception and mechanical hypernociception induced by carrageenan or complete Freund adjuvant (CFA). As positive controls it was used paracetamol in both acetic acid and formalin tests; dipyrone in capsaicin, glutamate and PMA-induced nociception; indomethacin in CFA and carrageenan-induced hypernociception models. In addition, the in vitro effects of BdE on COX-2 activity and on the activation of NF-kappa B were also evaluated. Results: BdE (50-400 mg/kg, p.o.) significantly diminished the abdominal constrictions induced by acetic acid, glutamate and CFA. Furthermore, BdE also inhibited the nociceptive responses in both phases of formalin-induced nociception. BdE, administered orally, also produced a long-lasting anti-hypernociceptive effect in the acute model of inflammatory pain induced by carrageenan. It was also observed the inhibition of COX-2 activity by BdE. Conclusion: In summary, the data reported in this work confirmed the traditional anti-inflammatory indications of Baccharis dracunculifolia leaves and provided biological evidences that Baccharis dracunculifolia, like Brazilian green propolis, possess antinociceptive and anti-inflammatory activities. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Baccharis dracunculifolia DC. (Asteraceae), popularly known as alecrim do campo, is a native plant from Brazil used in folk medicine as febrifuge, anti-inflammatory, antiseptic, and to treat skin sores. Also, B. dracanculifolia is the most important plant source of the Brazilian green propolis. which is recognized for its antiseptic and antiprotozoal activities. This study aimed at investigating the in vitro antiprotozoal. schistosomicidal, and antimicrobial activities of the essential oil from the leaves of R. dracunculifolia. The essential oil was obtained by hydrodistillation and analyzed by CC and GC/MS, which allowed the identification of 14 compounds, mainly oxygenated sesquiterpenes, such as ( E)nerolidol (33.51%) and spathulenol (16.24%). The essential oil showed activity against promzistigote forms of Leishmania donovani, with IC(50), values of 42 mu g/ml. The essential oil displayed high activity in the schistosomicidal assay, since all pairs of Schistosoma mansoni adult worms were dead after incubation with the essential oil (10, 50, and 100 fig/m1). B. dracunculifolia essential oil was neither cytotoxic against Vero cells, nor active in the antimicrobial and antiplasmodial assays.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Baccharis dracunculifolia is the most important vegetal source of propolis in southeast Brazil, and researchers have been investigating its biological properties. Propolis is a complex resinous hive product collected by bees from several plants, showing a very complex chemical composition. It has been employed since ancient times due to its therapeutic properties, such as antimicrobial, anti-inflammatory, antioxidant, immunomodulatory and antitumour activities, among others. The goal of this work was to compare the cytotoxic action of B. dracunculifolia, propolis and two isolated compounds (caffeic and cinnamic acids) on human laryngeal epidermoid carcinoma (HEp-2) cells in vitro. These cells were incubated with different concentrations of each variable, and cell viability was assessed by the crystal violet method. Lower concentrations of B. dracunculifolia (extract and essential oil), propolis, as well as caffeic and cinnamic acids, showed no cytotoxic activity against HEp-2 cells. On the other hand, elevated concentrations (50 and 100 mu g per 100 mu L) exerted a cytotoxic action, and propolis showed a more efficient action than its vegetal source and isolated compounds. Further investigation is still needed in order to explore the potential of these variables as antitumour agents and to understand their mechanisms of action.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Baccharis dracunculifolia DC (Asteraceae), a native plant from Brazil, commonly known as `Alecrim-do-campo` is widely used in folk medicine to treat inflammation, hepatic disorders and stomach ulcers, and it is the most important botanical source of Southeastern Brazilian propolis, known as green propolis. Its essential oil is composed of non-oxygenated and oxygenated terpenes. In this work, the effects of the essential oil obtained from the aerial parts of R dracunculifolia on gastric ulcers were evaluated. The antiulcer assays were undertaken using the following protocols in rats: nonsteroidal antiinflammatory drug (NSAID)-induced ulcer, ethanol-induced ulcer, stress-induced ulcer, and determination of gastric secretion using ligated pylorus. The treatment in the doses of 50, 250 and 500 mg/kg of R dracunculifolia essential oil significantly diminished the lesion index, the total lesion area and the percentage of lesions in comparison with both positive and negative control groups. With regard to the model of gastric secretion a reduction of gastric juice volume and total acidity was observed, as well as an increase in the gastric pH. No sign of toxicity was observed in the acute toxicity study. Considering the results, it is suggested that the essential oil of B. dracunculifolia could probably be a good therapeutic agent for the development of new phytotherapeutic medicine for the treatment of gastric ulcer. Copyright (C) 2009 John Wiley & Sons, Ltd.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In this work the effects of topic use of Brazilian green propolis gel in the contraction of wounds performed in rat`s skin was evaluated. In ten female Wistar rats were done four wounds in dorsal region. Two wounds in each rat were treated daily with Brazilian green propolis gel during 10 days. The wounds were photographed daily, and the images were analyzed with ImageJ software, in order to measure wound areas and evaluate wound contraction. In the graphic analysis, treated group and control group had similar behavior, and both evolved for complete closure in 10th experimentation day. The wound clots fell down before in treated wounds. Green propolis in the gel formulation at 5% in topical use had not effect in the process of wound contraction. The macroscopic visualization of the contraction of wounds, by itself, does not seem to be a good indicator of the process of tissue repair.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Initially, the seeds of Baccharis dracunculifolia were collected from populations of 10 different regions, and the cultivation experiment was carried out in an experimental area of 1,800 m(2) by cultivating 100 individuals of each population. The essential oil analyses were performed on both GC-FID and GUMS, which allowed the identification of 14 compounds. The oil yield varied from 0.31% to 0.70% among populations and season. The major oxygenated sesquiterpenes in the cultivated experiment were (E)-nerolidol (32%) and spathulenol (17%). The mean concentration in the plant of (E)-nerolidol was five times higher in March (136.53 mg/100 g of plant) than it was in July (25.03 mg/100 g of plant). The mean concentration of spathulenol increased about three fold from July (16.25 mg/100 g of plant) to April (47.50 mg/100 g of plant).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Lead (Pb) is recognized as one of the most toxic metals. Sources of Pb exposure have been widely documented in North America, and the removal of Pb additives from gasoline was reflected in a dramatic lowering of blood Pb concentration. In Latin America, the removal of Pb from gasoline resulted in decreased exposure, but Pb levels in many areas remain high due to occupational and environmental sources of exposure. While many of the Pb sources have been identified (mining, industries, battery recycling, lead-based paint, ceramics), new ones occasionally crop up. Here we report on blood Pb (B-Pb) levels in remote riverside communities of the Brazilian Amazon. Blood Pb (B-Pb) levels were determined in 448 persons from 12 villages of the Lower Tapajos River Basin, Par, Brazil. Socio-demographic and dietary information, as well as occupational, residential and medical history was collected using an interview-administered questionnaire. B-Pb, measured by ICP-MS, showed elevated concentrations. Mean B-Pb was 13.1 mu g/dL +/- 8.5, median B-Pb was 11.2 mu g/dL and ranged from 0.59 to 48.3 mu g/dL. Men had higher B-Pb compared to women (median: 15.3 mu g/dL vs 7.9 mu g/dL respectively). B-Pb increased with age for women, while it decreased for men. For both genders, B-Pb decreased with education. There were significant differences between villages. Exploratory analyses, using linear partition models, showed that for men B-Pb was lower among those who were involved in cattle-raising, and higher among those who hunted, farmed and fished. The distribution profile of B-Pb directed us towards artisanal transformation of manioc to flour (farinha), which requires heating in a large metal pan, with stirring primarily done by young men. In the village with the highest B-Pb, analysis of Pb concentrations (dry weight) of manioc (prior to transformation) and farinha (following transformation) from 6 houses showed a tenfold increase in Pb concentration (mean: 0.017 +/- 0.016 to 0.19 +/- 0.10 mu g/g). This was confirmed in one of these villages where we sampled manioc paste Oust before roasting) and the roasted farinha (0.05 mu g/g vs 0.20 mu g/g). While there may be other sources (ammunition, sinkers for fishing nets), the high concentrations in farinha, a dietary staple, assuredly makes an important contribution. Further action needs to reduce Pb sources in this region. (C) 2009 Elsevier Inc. All rights reserved.