713 resultados para dietary polyphenols


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Antioxidant activity and hepatoprotective properties of the aqueous extract and tetrahydrofuran-extracted phenolic fractions of Halimeda opuntia (Linnaeus) Lamouroux were investigated in rats with chemically induced liver injury. Total polyphenols were determined by using the Folin-Ciocalteau reagent. Liver damage was induced by CCl4 and assessed by a histological technique. Reverse transcription/polymerase chain reaction (RT/PCR) analysis showed increased superoxide dismutase (SOD) and catalase (CAT) gene expression and activities in the group treated with free phenolic acid (FPA) fractions of H. opuntia, suggesting inducing effects on both enzymes. In addition, rats treated with FPA fractions displayed lower liver thiobarbituric acid reactive substance (TBARS) levels than those observed for rats in the CCl4-treated group. These data suggest that the phenolic fractions from H. opuntia may protect the liver against oxidative stress-inducing effects of chemicals by modulating its antioxidant enzymes and oxidative status.

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Attempts to improve beef tenderness through supplementation with dietary vitamin D-3 have been challenged by null results and negative impacts on animal performance and carcass traits. Because vitamin D-3 is also synthesised by the animal via ultraviolet radiation from sunlight, the effectiveness of supplementation with dietary vitamin D-3 may be modulated by the degree of exposure of the animal to sunlight. Hence, this work aimed to verify whether dietary vitamin D-3 modifies meat quality without negatively affecting animal performance and carcass traits in B. indicus beef cattle that were either exposed to or protected from natural sunlight. Forty-two (411 +/- 38 kg) Nellore-type castrated males were fed a high-concentrate diet for 45 days after assignment to a treatment group. The treatments comprised combinations of three levels of vitamin D3 [ViTD - none (V0) or 2 x 10(6) IU of vitamin D-3 administered for either 2 (V2) or 8 (V8) consecutive days pre-slaughter] and two shading conditions (SHADE - unshaded or shaded). The post-mortem (pm) measurements were taken in the Longissimus thoracis et lumborum muscle. The animal performance and carcass traits were unaffected by ViTD or SHADE The V2 treatment increased the Myofibrillar Fragmentation Index in shaded animals compared to unshaded ones. Animals under shade had higher muscle calcium concentration. There was no effect of either ViTD or SHADE on the shear force. The L* values were higher at 24 h pm than at 0 and 1 h pm, with no differences among the animals in the ViTD or SHADE groups. Higher a* values were observed among animals in the V8 group than in the V0 group, and higher b* values were observed among animals in the V8 group than in the V2 or V0 groups, which were not different. In conclusion, ViTD and SHADE did not affect animal performance, carcass traits or shear force, whereas animals receiving a lower ViTD dosage and SHADE exhibited altered myofibrillar fragmentation. ViTD affected the colour parameters, and changes in the lightness of the beef related to the time pm were found in meat from animals under SHADE. (c) 2012 Elsevier B.V. All rights reserved.

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Several epidemiological and experimental studies has been reported that lutein (LT) presents antioxidant properties. Aim of the present study was to investigate the protective effects of LT against oxidative stress and DNA damage induced by cisplatin (cDDP) in a human derived liver cell line (HepG2). Cell viability and DNA-damage was monitored by MU and comet assays. Moreover, different biochemical parameters related to redox status (glutathione, cytochrome-c and intracellular ROS) were also evaluated. A clear DNA-damage was seen with cDDP (1.0 mu M) treatment. In combination with the carotenoid, reduction of DNA damage was observed after pre- and simultaneous treatment of the cells, but not when the carotenoid was added to the cells after the exposure to cDDP. Exposure of the cells to cDDP also caused significant changes of all biochemical parameters and in co-treatment of the cells with LT, the carotenoid reverted these alterations. The results indicate that cDDP induces pronounced oxidative stress in HepG2 cells that is related to DNA damage and that the supplementation with the antioxidant LT may protect these adverse effects caused by the exposure of the cells to platinum compound, which can be a good predict for chemoprevention. (C) 2011 Elsevier Ltd. All rights reserved.

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The market for cosmeceuticals continues with significant annual growth, but today consumers are more aware of nutritional products that contribute to both skin health and disease prevention. In the last 10 years, pharmacists, chemists, nutritionists, and physicians have been working together to develop new nutritional applications to satisfy peoples needs and demands. As a recent result of convergence phenomenon between cosmetics and food industries, nutricosmetics is a blurry area unfamiliar to many consumers and sometimes even to foods and cosmetics experts. Characterized by oral supplementation of nutrients, nutricosmetics are also known as beauty pills,beauty from within, and even oral cosmetics. The major claim is the antiaging effect, reducing wrinkles by fighting free radicals generated by solar radiation. Among the ingredients used in nutricosmetics, antioxidants represent the most crucial. The best-known antioxidants are carotenoids (beta-carotene, lycopene, lutein, zeaxanthin, and astaxanthin) and polyphenols (anthocyanidins, catechins, flavonoids, tannins, and procyanidins). This study presents an overview about the concept of nutricosmetics and gives us information about the difference between nutricosmetics, nutraceuticals, and cosmeceuticals. The article also discusses about carotenoids and polyphenols, two classes of ingredients often employed in such products.

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The scope of this study was to estimate calibrated values for dietary data obtained by the Food Frequency Questionnaire for Adolescents (FFQA) and illustrate the effect of this approach on food consumption data. The adolescents were assessed on two occasions, with an average interval of twelve months. In 2004, 393 adolescents participated, and 289 were then reassessed in 2005. Dietary data obtained by the FFQA were calibrated using the regression coefficients estimated from the average of two 24-hour recalls (24HR) of the subsample. The calibrated values were similar to the the 24HR reference measurement in the subsample. In 2004 and 2005 a significant difference was observed between the average consumption levels of the FFQA before and after calibration for all nutrients. With the use of calibrated data the proportion of schoolchildren who had fiber intake below the recommended level increased. Therefore, it is seen that calibrated data can be used to obtain adjusted associations due to reclassification of subjects within the predetermined categories.

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Background: Given the importance of both calcium and vitamin D for bone health and the high prevalence of vitamin D from around the world, the present study aimed to evaluate calcium and vitamin D intake in a group of healthy Brazilian adolescents and young adults and to examine the influence of breakfast and dairy products in the total intake of these nutrients. Methods: One hundred and sixty adolescents and young adults, aged 1620 years old, from a public school, participated in the present study. Three-day dietary records were used to assess calcium and vitamin D intakes. Serum 25(OH) D levels were measured using a radioimmunoassay kit. The results were expressed as the mean (SD). Results: Only 3.8% of the subjects met the daily adequate intake recommendation for calcium, and none for vitamin D [682.2 (132.2) mg day(-1) and 124.0 (28.0) IU day(-1), respectively]. 25(OH) D serum levels were insufficient in 51.5% and deficient in 9.7% of the individuals [72.5 (22.3) nmol L(-1)]. There was a significant positive correlation between dairy product intake with both calcium and vitamin D (r = 0.597 and r = 0.561, respectively; P = 0.000). Adolescents who ate breakfast had a significant higher mean calcium, vitamin D and dairy product intake than adolescents who did not report this meal. Conclusions: The majority of adolescents and young adults did not consume recommended intakes of calcium and vitamin D and also presented 25(OH) D insufficiency. The results indicate that a regular breakfast and the consumption of dairy products represent important strategies in improving calcium and vitamin D intake in the diet.

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We investigated dietary intake patterns (DIP) in adolescents (14-18 year-olds) and the association with demographic and socioeconomic characteristics and lifestyle variables. This school-based survey was carried out among high school students from the city of Maringa in the state of Parana (PR), Brazil (2007). The sample included 991 students (54.5% girls) from high schools. DIPs were investigated by the frequency of weekly consumption of each food group: vegetables, fruit, rice, beans, fried food, sweet food, milk, soda, meat, eggs, alcoholic drinks. Independent variables were: demographic and socioeconomic characteristics and lifestyle variables. DIPS were identified using principal component analysis with orthogonal rotation (varimax). Three components were extracted. Component 1 (fried foods, sweets and soft drinks) was positively associated with not having breakfast for girls and dinner for boys. Moreover, component 2 (consumption of fruit and vegetables) was positively associated with having breakfast at home for boys and number of meals for girls. Component 3 (beans, eggs and meat) was positively associated with having lunch, employment and sedentary behavior level for girls. However, it was negatively associated with having lunch and dinner for boys. Adolescents who have healthier eating patterns also had other healthier behaviors regardless of gender. However, factors associated with dietary patterns differ between boys and girls. (C) 2012 Elsevier Ltd. All rights reserved.

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BACKGROUND: The objectives of this study were (1) to evaluate the content of ellagic acid in fruits consumed by the Brazilian population, including native ones; (2) to further characterize rich sources in relation to ascorbic acid, phenolics contents and in vitro antioxidant capacity; and (3) to study the distribution and effect of ripening stage on ellagitannins content of jabuticaba (Myrciaria jaboticaba). The content of free ellagic acid and ellagic acid derivatives such as ellagitannins was analyzed using high-performance liquid chromatography (HPLC). RESULTS: Ellagic acid was detected in 10 out of a total of 35 fruits analyzed. The content of free ellagic acid in fruits varied from 0.0028 to 0.085 g kg(-1) (FW) and total ellagic acid varied from 0.215 to 3.11 g kg(-1) (FW). All the seven fruits belonging to the Myrtaceae family evaluated in this study presented high contents of ellagitannins in their composition, with jabuticaba, grumixama and cambuci (all native from Brazil) showing the highest total ellagic acid contents. Jabuticaba, the most consumed in Brazilamongthose and already adapted to commercial plantations, contained concentrated phenolics compounds, including ellagitannins, in the peel. Anthocyanins (cyanidin derivatives) increased significantly through ripening of jabuticaba and were not present in the pulp or seeds. Samples collected from three different locations during summer, winter and spring had total ellagic contents varying from 1.88 to 3.31 g kg(-1) (FW). The decrease in ellagic acid content with ripening was more accentuated for pulp (eight times) compared to seeds (2.3 times) and peel (2.0 times). CONCLUSION: These results showed the potential of jabuticaba as dietary source of ellagic acid and reinforced consumption of the whole fruit by the population. (C) 2011 Society of Chemical Industry