989 resultados para Green Technology


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BACKGROUND: There has been growing interest in sodium copper chlorophyllin (Cu-Chl) as a food colourant and supplement owing to its beneficial biological activities. Studies have revealed that this green pigment inhibits experimental carcinogenesis and interacts with proteins and genotoxic agents. Health-related activities have also been associated with the prevention of lipid peroxidation. However, intestinal absorption of this pigment has been considered insignificant, raising questions of whether eventual biological properties are related to pre- or post-absorptive actions. In this study, intestinal absorption of Cu-Chl and its appearance in serum and organs were estimated by high-performance liquid chromatography analysis in rat feeding experiments. The effect of ingested Cu-Chl on lipid peroxidation was analysed by measuring thiobarbituric acid-reactive substances and antioxidant enzyme activities in hepatic and brain tissues of oxidative stress-induced rats. RESULTS: The two main components of commercial Cu-Chl, namely Cu-chlorin e(6) and Cu-chlorin e(4), showed different digestive behaviours, and only Cu-chlorin e4 was found in serum, liver and kidneys. Antioxidant activity in vivo could be observed in brain and seemed to be related to in situ protection but not to antioxidant enzyme modulation. CONCLUSION: As at least one of the major components of Cu-Chl is effectively absorbed, further pharmacolkinetic studies are encouraged to access absorption rates and the role of ingested copper chlorophyllins in mammals. (C) 2009 Society of Chemical Industry

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Green tea (Camellia sinensis) and Ginkgo biloba extracts in cosmetic formulations have been suggested to protect the skin against UV-induced damage and skin ageing. Thus, it is very important to assess the human skin penetration of their major flavonoids to verify if they penetrate and remain in the skin to exert their proposed effects. The aim of this study was to evaluate the human skin penetration of epigallocatechin-3-gallate (EGCG) and quercetin from green tea and G. biloba extracts vehiculated in cosmetic formulations. This study was conducted with fresh dermatomed human Caucasian skin from abdominal surgery mounted on static Franz diffusion cells. Skin samples were mounted between two diffusion half-cells and 10 mg/cm(2) of formulations supplemented with 6% of green tea or G. biloba extract were applied on the skin surface. The receptor fluid was removed after 6 and 24 h and analyzed by high-performance liquid chromatography for the quantification of the flavonoids. The stratum corneum was removed by tape stripping and immersed in methanol and the epidermis was mechanically separated from the dermis and triturated in methanol to extract EGCG and quercetin. The results showed that the flavonoids under study penetrated into the skin, without reaching the receptor fluid. The majority of EGCG was quantified in the stratum corneum (0.87 mu g/cm(2)), which was statistically higher than the EGCG concentrations found in viable epidermis (0.54 mu g/cm(2)) and in the dermis (0.38 mu g/cm(2)). The majority of quercetin was quantified in the viable epidermis (0.23 mu g/cm(2)), which was statistically higher than the EGCG concentration found in the stratum corneum layer (0.17 mu g/cm(2)). Finally, it can be concluded that EGCG and quercetin from green tea and G. biloba extracts vehiculated in cosmetic formulations presented good skin penetration and retention, which can favor their skin effects. Copyright (C) 2009 S. Karger AG, Basel

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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 Ireland Ltd. All rights reserved.

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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.

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The in vitro antileishmanial activity of Brazilian green propolis hydroalcoholic extract (BPE) were carried out on Leishmania (Viannia) braziliensis against both promastigote (doses ranging from 1 to 750 mu g mL(-1)) and amastigote (10, 100, and 250 mu g mL(-1)) assays in comparison with the positive (amphotericin B) and negative (dimethyl sulfoxide at 1% in physiologic solution) control groups. BPE displayed in vitro antileishmanial activities against promastigote forms of the parasite (p<0.05). However, it was inactive against its amastigote ones. In the in vitro cytotoxicity assay against Vero cells, BPE showed no cytotoxicity in the maximum doses tested. The high-performance liquid chromatography analysis allowed the identification of caffeic acid, p-coumaric acid, aromadendrine-4`-methyl-ether, 3-prenyl-p-coumaric acid (drupanin), and 3,5-diprenil-p-cumarico acid (artepillin C) as major compounds of BPE. In the in vivo assay, using a Balb/C lineage of Mus musculus male mice, groups of ten animals each were treated (1.5 mg kg day(-1)) with BPE orally (group 1), BPE topically (group 2), BPE orally and topically (group 3), and glucantime (group 4), using NaCl 0.9% (group 5) as the negative control group. Groups 1, 2, and 3 displayed a decrease on lesion development, after 90 days of treatment, by 78.6%, 84.3%, and 90.0%, respectively, while the glucantime-treated group showed 57.7% of decrease, all in comparison with the negative control group. It is the first time that the in vivo antileishmanial activity has been reported for Brazilian green propolis.

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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.

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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.

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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.

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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).

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Modern lifestyle markedly changed eating habits worldwide, with an increasing demand for ready-to-eat foods, such as minimally processed fruits and leafy greens. Packaging and storage conditions of those products may favor the growth of psychrotrophic bacteria, including the pathogen Listeria monocytogenes. In this work, minimally processed leafy vegetables samples (n = 162) from retail market from Ribeirao Preto, Sao Paulo, Brazil, were tested for the presence or absence of Listeria spp. by the immunoassay Listeria Rapid Test, Oxoid. Two L. monocytogenes positive and six artificially contaminated samples of minimally processed leafy vegetables were evaluated by the Most Probable Number (MPN) with detection by classical culture method and also culture method combined with real-time PCR (RTi-PCR) for 16S rRNA genes of L monocytogenes. Positive MPN enrichment tubes were analyzed by RTi-PCR with primers specific for L. monocytogenes using the commercial preparation ABSOLUTET (TM) QPCR SYBR (R) Green Mix (ABgene, UK). Real-time PCR assay presented good exclusivity and inclusivity results and no statistical significant difference was found in comparison with the conventional culture method (p < 0.05). Moreover, RTi-PCR was fist and easy to perform, with MPN results obtained in ca. 48 h for RTi-PCR in comparison to 7 days for conventional method. (C) 2009 Elsevier Ltd. All rights reserved.

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The results presented in this report form a part of a larger global study on the major issues in BPM. Only one part of the larger study is reported here, viz. interviews with BPM experts. Interviews of BPM tool vendors together with focus groups involving user organizations, are continuing in parallel and will set the groundwork for the identification of BPM issues on a global scale via a survey (including a Delphi study). Through this multi-method approach, we identify four distinct sets of outcomes. First, as is the focus of this report, we identify the BPM issues as perceived by BPM experts. Second, the research design allows us to gain insight into the opinions of organisations deploying BPM solutions. Third, an understanding of organizations’ misconceptions of BPM technologies, as confronted by BPM tool vendors is obtained. Last, we seek to gain an understanding of BPM issues on a global scale, together with knowledge of matters of concern. This final outcome is aimed to produce an industry driven research agenda which will inform practitioners and in particular, the research community world-wide on issues and challenges that are prevalent or emerging in BPM and related areas.

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The demand for more pixels is beginning to be met as manufacturers increase the native resolution of projector chips. Tiling several projectors still offers a solution to augment the pixel capacity of a display. However, problems of color and illumination uniformity across projectors need to be addressed as well as the computer software required to drive such devices. We present the results obtained on a desktop-size tiled projector array of three D-ILA projectors sharing a common illumination source. A short throw lens (0.8:1) on each projector yields a 21-in. diagonal for each image tile; the composite image on a 3×1 array is 3840×1024 pixels with a resolution of about 80 dpi. The system preserves desktop resolution, is compact, and can fit in a normal room or laboratory. The projectors are mounted on precision six-axis positioners, which allow pixel level alignment. A fiber optic beamsplitting system and a single set of red, green, and blue dichroic filters are the key to color and illumination uniformity. The D-ILA chips inside each projector can be adjusted separately to set or change characteristics such as contrast, brightness, or gamma curves. The projectors were then matched carefully: photometric variations were corrected, leading to a seamless image. Photometric measurements were performed to characterize the display and are reported here. This system is driven by a small PC cluster fitted with graphics cards and running Linux. It can be scaled to accommodate an array of 2×3 or 3×3 projectors, thus increasing the number of pixels of the final image. Finally, we present current uses of the display in fields such as astrophysics and archaeology (remote sensing).

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