916 resultados para Erva mate


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No presente estudo foi verificado o efeito da temperatura de consumo na equivalência de doçura e no poder edulcorante de diferentes agentes adoçantes em bebida de chá-mate em pó solúvel. Foram avaliados: aspartame, sucralose, mistura ciclamato/sacarina 2:1, Stevia e acessulfame-K, tendo como referência a sacarose. Todos os estudos foram realizados a 6±2ºC e a 45±2ºC. Primeiramente foi determinada a doçura ideal, utillizando-se escala do ideal com 30 provadores consumidores da bebida. Em seguida, foi determinada a doçura equivalente à sacarose (na doçura considerada ideal) para cada edulcorante estudado, e seu poder edulcorante nas duas temperaturas de estudo. Para tal foi aplicado o método de estimação de magnitude, utilizando-se uma equipe de 10 provadores selecionados e treinados. A doçura ideal de sacarose foi de 8,3% para a bebida de chá-mate solúvel, sem diferença significativa entre as temperaturas de estudo. Ocorreram diferenças sensoriais importantes em função da temperatura, pois, enquanto para alguns edulcorantes o aumento de temperatura provocou diminuição na potência edulcorante, para outros foi observado aumento do poder edulcorante. Portanto, não se deve generalizar as alterações no poder edulcorante em função da temperatura, pois ela pode variar em função da classe química envolvida e do meio de dispersão em que se encontra.

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Os estudos do chá verde brasileiro (Camellia sinensis var assamica) ainda são escassos quando comparados aos realizados com chás verdes produzidos em outros países. Os objetivos deste trabalho foram avaliar os efeitos do tempo de infusão, forma de acondicionamento da erva (a granel ou em sachês) e forma de preparo da bebida na extração dos biativos do chá verde brasileiro e na estabilidade da bebida obtida. Foram avaliados os parâmetros sólidos solúveis e compostos fenólicos extraídos, bem como as propriedades antioxidantes da bebida pelo método DPPH (radicais 2,2-difenil-1-picrilhidrazil). Os dados obtidos evidenciam que o uso da erva a granel sob agitação e tempo de infusão de 5 minutos foi a condição mais propícia para a extração dos bioativos do chá verde. Aumentando-se o volume de preparação da bebida sem alteração da razão erva:água, aumentou-se a eficiência da extração dos bioativos, devido ao fato de que o resfriamento de volumes maiores é mais demorado que o resfriamento de volumes menores. As bebidas obtidas foram estáveis por 24 horas em temperatura ambiente e em geladeira, visto não terem sido detectadas redução das propriedades antioxidantes e variações significativas dos seus principais bioativos epigalocatequina galato, epicatequina, catequina e cafeína.

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O presente trabalho teve por objetivo estudar a metodologia do teste de envelhecimento acelerado para avaliação do potencial fisiológico de sementes de erva-doce, bem como avaliar a eficiência do uso de solução saturada de sal no controle da absorção de água pelas sementes durante a realização do teste. Para tanto, quatro lotes de sementes de erva-doce foram submetidos aos testes de germinação, emergência das plântulas em casa de vegetação e envelhecimento acelerado (41ºC; 48, 72 e 96h); conduzindo-se o procedimento tradicional e a alternativa com o uso de solução saturada de NaCl. Diante dos resultados obtidos, verificou-se que as sementes de erva-doce expostas a solução saturada de NaCl durante o teste de envelhecimento acelerado captam menor quantidade de água, verificando-se taxa de deterioração menos acentuada, resultados menos drásticos e mais uniformes que os obtidos com o procedimento tradicional. A exposição no teste de envelhecimento acelerado durante 72h, a 41ºC, com o uso de solução saturada de NaCl, constitui opção promissora para avaliação do potencial fisiológico das sementes dessa espécie.

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Matings systems using signals for sexual communication have been studied extensively and results commonly suggest that females use these signals for locating males, species-identification, and mate choice. Although numerous mating systems employ multiple signals, research has generally focused on long-range signals perhaps due to their prominence and ease of study. This study focused on the short-range acoustic courtship song of crickets. The results presented here suggest this signal is under selection by female choice. Females mated preferentially with males having shorter silences between the two types of ticks within the song. The length of these silences (Gap 1) was correlated with male condition such that males having long silences were significantly lower in mass with respect to body size when compared to males having short silences. Both Gap 1 length and male condition were significantly repeatable within males over time suggesting the possibility these traits have a genetic basis. This study is the first empirical study to test female preferences within the natural variation of the courtship song. It now appears, at least in crickets, that both the longand short-range signals of a multi-signal mating system may contribute to male mating success.

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Cualquier hecho hist??rico es dif??cil de comprender por los alumnos debido a la abstracci??n que deben hacer y por imaginar una forma de vida, en este caso, la Prehistoria, muy diferente a la que llevamos actualmente. Para una mejor comprensi??n y un conocimiento de los antepasados que poblaron la zona, los alumnos se convertir??n en personajes de la ??poca tratada y realizar??n las mismas vivencias que los hombres prehist??ricos. Los escenarios de grabaci??n ser??n la playa de Cuevas de Mar y alrededores, las cuevas de la zona y los bosques. El resultado es un v??deo cuyos autores son el grupo de teatro del C.P. de Nueva, los di??logos son de Arsenio Gonz??lez y Fernando Bada.

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The populations of many species are structured such that mating is not random and occurs between members of local patches. When patches are founded by a single female and all matings occur between siblings, brothers may compete with each other for matings with their sisters. This local mate competition (LMC) selects for a female-biased sex ratio, especially in species where females have control over offspring sex, as in the parasitic Hymenoptera. Two factors are predicted to decrease the degree of female bias: (1) an increase in the number of foundress females in the patch and (2) an increase in the fraction of individuals mating after dispersal from the natal patch. Pollinating fig wasps are well known as classic examples of species where all matings occur in the local patch. We studied non-pollinating fig wasps, which are more diverse than the pollinating fig wasps and also provide natural experimental groups of species with different male morphologies that are linked to different mating structures. In this group of wasps, species with wingless males mate in the local patch (i.e. the fig fruit) while winged male species mate after dispersal. Species with both kinds of male have a mixture of local and non-local mating. Data from 44 species show that sex ratios (defined as the proportion of males) are in accordance with theoretical predictions: wingless male species < wing-dimorphic male species < winged male species. These results are also supported by a formal comparative analysis that controls for phylogeny. The foundress number is difficult to estimate directly for non-pollinating fig wasps but a robust indirect method leads to the prediction that foundress number, and hence sex ratio, should increase with the proportion of patches occupied in a crop. This result is supported strongly across 19 species with wingless males, but not across 8 species with winged males. The mean sex ratios for species with winged males are not significantly different from 0.5, and the absence of the correlation observed across species with wingless males may reflect weak selection to adjust the sex ratio in species whose population mating structure tends not to be subdivided. The same relationship is also predicted to occur within species if individual females adjust their sex ratios facultatively. This final prediction was not supported by data from a wingless male species, a male wing-dimorphic species or a winged male species.

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The most popular endgame tables (EGTs) documenting ‘DTM’ Depth to Mate in chess endgames are those of Eugene Nalimov but these do not recognise the FIDE 50-move rule ‘50mr’. This paper marks the creation by the first author of EGTs for sub-6-man (s6m) chess and beyond which give DTM as affected by the ply count pc. The results are put into the context of previous work recognising the 50mr and are compared with the original unmoderated DTM results. The work is also notable for being the first EGT generation work to use the functional programming language HASKELL.

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1. To maximize the probability of rapid contact with a female’s pheromone plume, the trajectories of male foraging flights might be expected to be directed with respect to wind flow and also to be energetically efficient. 2. Flights directed either upwind, downwind, or crosswind have been proposed as optimal strategies for rapid and/or energetically efficient plume contact. Other possible strategies are random and Lévy walks, which have trajectories and turn frequencies that are not dictated by the direction of wind flow. 3. The planar flight paths of males of the day-active moth Virbia lamae were recorded during the customary time of its sexual activity. 4. We found no directional preference in these foraging flights with respect to the direction of contemporaneous wind flow, but, because crosswind encompasses twice the possible orientations of either upwind or downwind, a random orientation is in effect a de facto crosswind strategy. 5. A crosswind preference should be favoured when the plume extends farther downwind than crosswind, and this strategy is realized by V. lamae males by a random orientation of their trajectories with respect to current wind direction

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The inhibitory effects of mate tea (MT), a beverage produced with leaves from Ilex paraguariensis, in vitro lipase activity and on obesity in obese mice models were examined. For the in vitro experiment, porcine and human pancreatic lipase (PL) activities were determined by measuring the rate of release of oleic acid from hydrolysis of olive oil emulsified with taurocholate, phospholipids, gum arabic, or polyvinyl alcohol. For the in vivo experiments, animals were fed with a standard diet (SD, n = 10) or high-fat diet (HFD, n = 30) for 16 weeks. After the first 8 weeks on the HFD, the animals were treated with 1 and 2 g/kg of body weight of MT. The time course of the body weight and obesity-related biochemical parameters were evaluated. The results showed that MT inhibited both porcine and human PL (half-maximal inhibitory concentration = 1.5 mg MT/ml) and induced a strong inhibition of the porcine lipase activity in the hydrolysis of substrate emulsified with taurocholate + phosphatidylcholine (PC) (83 +/- 3.8%) or PC alone (62 +/- 4.3%). MT suppressed the increases in body weight (P < 0.05) and decreased the serum triglycerides and low-density lipoprotein (LDL)-cholesterol concentrations at both doses (from 190.3 +/- 5.7 to 135.0 +/- 8.9 mg/dl, from 189.1 +/- 7.3 to 129.3 +/- 17.6 mg/dl; P < 0.05, respectively) after they had been increased by the HFD. The liver lipid content was also decreased by the diet containing MT (from 132.6 +/- 3.9 to 95.6 +/- 6.1 mg/g of tissue; P < 0.05). These results suggest that MT could be a potentially therapeutic alternative in the treatment of obesity caused by a HFD.

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Because the potential of yerba mate (Ilex paraguariensis) has been suggested in the management of obesity, the aim of the present study was to evaluate the effects of yerba mate extract on weight loss, obesity-related biochemical parameters, and the regulation of adipose tissue gene expression in high-fat diet-induced obesity in mice. Thirty animals were randomly assigned to three groups. The mice were introduced to standard or high-fat diets. After 12 weeks on a high-fat diet, mice were randomly assigned according to the treatment (water or yerba mate extract 1.0 g/-kg). After treatment intervention, plasma concentrations of total cholesterol, high-density lipoprotein cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, and glucose were evaluated. Adipose tissue was examined to determine the mRNA levels of several genes such as tumor necrosis factor-alpha (TNF-alpha), leptin, interleukin-6 (IL-6), C-C motif chemokine ligand-2 (CCL2), CCL receptor-2 (CCR2), angiotensinogen, plasminogen activator inhibitor-1 (PAI-1), adiponectin, resistin, peroxisome proliferator-activated receptor-gamma(2) (PPAR-gamma(2)), uncoupling protein-1 (UCP1), and PPAR-gamma coactivator-1 alpha (PGC-1 alpha). The F4/80 levels were determined by immunoblotting. We found that obese mice treated with yerba mate exhibited marked attenuation of weight gain, adiposity, a decrease in epididymal fat-pad weight, and restoration of the serum levels of cholesterol, triglycerides, LDL cholesterol, and glucose. The gene and protein expression levels were directly regulated by the high-fat diet. After treatment with yerba mate extract, we observed a recovery of the expression levels. In conclusion, our data show that yerba mate extract has potent antiobesity activity in vivo. Additionally, we observed that the treatment had a modulatory effect on the expression of several genes related to obesity.

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The radiation food processing has been demonstrating great effectiveness in the attack of pathogenic agents, while little compromising nutritional value and sensorial properties of foods. The mate (Ilex paraguariensis), widely consumed product in South America, generally in the form of infusions with hot or cold water, calls of chimarrao or terere, it is cited in literature as one of the best sources phenolic compounds. The antioxidants action of these constituent has been related to the protection of the organism against the free radicals, generated in alive, currently responsible for the sprouting of some degenerative illness as cancer, arteriosclerosis, rheumatic arthritis and cardiovascular clutters among others. The objective of that work was to evaluate the action of the processing for gamma radiation in phenolic compounds of terere beverage in the doses of 0, 3, 5, 7 and 10 kGy. The observed results do not demonstrate significant alterations in phenolic compounds of terere beverage processed by gamma radiation. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

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The antioxidant activity of mate tea, the roasted product derived from yerba mate (Ilex paraguarienis), was observed in vitro and in animal models, but studies in humans are lacking. The aim of this study was to investigate the effects of mate tea supplementation on plasma susceptibility to oxidation and on antioxidant enzyme gene expression in healthy nonsmoking women, after acute or prolonged ingestion. We evaluated plasma total antioxidant status (TAS), the kinetics of diene conjugate generation, and thiobarbituric acid reactive substance (TBARS) contents in plasma, as well as mRNA levels of antioxidant gluthatione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). After the supplementation period with mate tea, lipid peroxidation was acutely lowered, an effect that was maintained after prolonged administration. Total antioxidant status and the level of antioxidant enzyme gene expression were also demonstrated after prolonged consumption. These results suggest that regular consumption of mate tea may increase antioxidant defense of the body by multiple mechanisms.

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Mate (Ilex paraguariensis) is rich in polyphenolic compounds, which are thought to contribute to the health benefits of tea. Mate tea was administered orally to mice at a dose of 0.5, 1.0 or 2.0 g/kg for 60 d, and changes both in serum lipid concentration and fatty acid composition of liver and kidney were examined. The effects of mate tea on serum and tissue lipid peroxidation were assessed by the evaluation of thiobarbituric acid-reactive substances (TBARS). In tea-consuming mice, both MUFA (18: 1n-9) and PUFA (18: 2n-6 and 20: 4n-6) were increased (P<0.05) in the liver lipid (approximately 90 and 60%, respectively), whereas only MUFA (approximately 20%) were increased in the kidney lipid. The most altered PUFA class was n-6 PUFA, which increased by approximately 60-75 % (P<0.05). This difference in the fatty acid profile in the liver is reflected in the increased PUFA:SFA ratio. Consistent with these results, mice fed with mate tea had much lower TBARS in the liver. No differences (P>0.05) were found in the levels of serum cholesterol, HDL-cholesterol and TAG under the conditions of the present study. These results suggest that treatment with mate tea was able to protect unsaturated fatty acids from oxidation and may have selective protective effects within the body, especially on the liver.

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Yerba mate (Ilex paraguariensis) is rich in polyphenols, especially chlorogenic acids. Evidence suggests that dietary polyphenols could play a role in glucose absorption and metabolism. The aim of this study was to evaluate the antidiabetic properties of yerba mate extract in alloxan-induced diabetic Wistar rats. Animals (n = 41) were divided in four groups: nondiabetic control (NDC, n = 10), nondiabetic yerba mate (NDY, n = 10), diabetic control (DC, n = 11), and diabetic yerba mate (NDY, n = 10). The intervention consisted in the administration of yerba mate extract in a 1 g extract/kg body weight dose for 28 days; controls received saline solution only. There were no significant differences in serum glucose, insulin, and hepatic glucose-6-phosphatase activity between the groups that ingested yerba mate extract (NDY and DY) and the controls (NDC and DC). However, the intestinal SGLT1 gene expression was significantly lower in animals that received yerba mate both in upper (p = 0.007) and middle (p < 0.001) small intestine. These results indicate that bioactive compounds present in yerba mate might be capable of interfering in glucose absorption, by decreasing SGLT1 expression.