989 resultados para carotene


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PURPOSE: We investigated risk factors for colorectal cancer in early-onset cancers, to provide quantitative estimates for major selected risk factors. METHODS: We analyzed data from three Italian and Swiss case-control studies conducted between 1985 and 2009, including 329 colorectal cancer cases and 1,361 controls aged ≤45 years. We computed odds ratios (ORs) from unconditional logistic regression models, adjusted for major confounding factors. RESULTS: The OR of young-onset colorectal cancer was 4.50 for family history of colorectal cancer in first-degree relatives, the association being higher in subjects with affected siblings (OR 11.68) than parents (OR 3.75). The ORs of young-onset colorectal cancer were 1.56 for ≥14 drinks/week of alcohol, 1.56 for the highest tertile of processed meat, 0.40 for vegetables, 0.75 for fruit, and 0.78 for fish intake. Among micronutrients, the ORs were 0.52 for β-carotene, 0.68 for vitamin C, 0.38 for vitamin E, and 0.59 for folate. No significant associations emerged for physical activity, overweight, and diabetes. CONCLUSIONS: This study-the largest on young-onset colorectal cancer-confirms that several recognized risk factors for colorectal cancer are also relevant determinants of young-onset colorectal cancer. Family history of colorectal cancer in particular is a stronger risk factor in young subjects, as compared to middle age and elderly ones.

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An experiment was conducted to determine the fruit size, mineral composition and quality of trickle-irrigated tomatoes as affected by potassium fertilizer rates. Six potassium (K) rates were applied as KCl, corresponding to 0, 48.4, 118.6, 188.8, 259.0 and 399.4 kg ha-1, with four replicates, following a randomized block design. Quadratic responses to K rates were observed for double extra large (diameter > 60 mm), extra large (56 to 60 mm) and large (52 to 56 mm) fruit yields. Maximum yields of these classes were achieved with K rates of 116, 190 and 233 kg ha-1, respectively. Fruit dry matter, phosphorus, sulfur and magnesium contents were not affected by K rates, but nitrate and K contents showed significant increments as K rates were increased. Vitamin C, total soluble solids, lycopene and beta-carotene contents in the fruits were not affected by K rates. Increments in the K rate lowered the fruit pH and increased total acids content.

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Background:Besides tobacco and alcohol, dietary habits may have a relevant role in oral cavity and pharyngeal (OCP) cancer.Methods:We analysed the role of selected food groups and nutrients on OCP cancer in a case-control study carried out between 1997 and 2009 in Italy and Switzerland. This included 768 incident, histologically confirmed squamous cell carcinoma cases and 2078 hospital controls. Odds ratios (ORs) were estimated using logistic regression models including terms for tobacco, alcohol and other relevant covariates.Results:Significant inverse trends in risk were observed for all vegetables (OR=0.19, for the highest vs the lowest consumption) and all fruits (OR=0.39), whereas significant direct associations were found for milk and dairy products (OR=1.50), eggs (OR=1.71), red meat (OR=1.55), potatoes (OR=1.85) and desserts (OR=1.68), although trends in risk were significant only for potatoes and desserts. With reference to nutrients, significant inverse relations were observed for vegetable protein (OR=0.45, for the highest vs the lowest quintile), vegetable fat (OR=0.54), polyunsaturated fatty acids (OR=0.53), α-carotene (OR=0.51), β-carotene (OR=0.28), β-cryptoxanthin (OR=0.37), lutein and zeazanthin (OR=0.34), vitamin E (OR=0.26), vitamin C (OR=0.40) and total folate (OR=0.34), whereas direct ones were observed for animal protein (OR=1.57), animal fat (OR=2.47), saturated fatty acids (OR=2.18), cholesterol (OR=2.29) and retinol (OR=1.88). Combinations of low consumption of fruits and vegetables, and high consumption of meat with high tobacco and alcohol, led to 10- to over 20-fold excess risk of OCP cancer.Conclusion:Our study confirms and further quantifies that a diet rich in fruits and vegetables and poor in meat and products of animal origin has a favourable role against OCP cancer.

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OBJECTIVE: To assess nutrition trends of the Geneva population for the period 1999-2009. DESIGN: Bus Santé Geneva study, which conducts annual health surveys in random samples of the Geneva population. Dietary intake was assessed using a validated FFQ and trends were assessed by linear regression. SETTING: Population-based survey. SUBJECTS: Data from 9283 participants (50% women, mean age 51·5 (sd 10·8) years) were analysed. RESULTS: In both genders total energy intake decreased from 1999 to 2009, by 2·9% in men and by 6·3% in women (both trends P < 0·005). Vegetable protein and total carbohydrate intakes, expressed as a percentage of total energy intake, increased in women. MUFA intake increased while SFA, PUFA and alcohol intakes decreased in both genders. Intakes of Ca, Fe and carotene decreased in both genders. No changes in fibre, vitamin D and vitamin A intakes were found. Similar findings were obtained after excluding participants with extreme dietary intakes, except that the decreases in SFA, vegetable protein and carbohydrate were no longer significant in women. CONCLUSIONS: Between 1999 and 2009, a small decrease in total energy intake was noted in the Geneva population. Although the decrease in alcohol and SFA intakes is of interest, the decrease in Ca and Fe intakes may have adverse health effects in the future.

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Mauritia vinifera (buriti) is a palm tree that grows wild in different areas of Brazil, particularly in the Amazonian region. The buriti oil is rich in carotenoids, especially in β-carotene. The growing interest in other natural sources of β-carotene has stimulated the industrial use of buriti as a raw material for pulp oil extraction. Most processes are based on the conventional technologies, involving drying and pressing the pulp for oil recovery and further separation of carotenoids in a liquid phase using organics solvents. In the present work, the ethanol-based process was evaluated for simultaneous carotenoids recovering and fractionating from buriti pulp. The raw material and ethanol, 1:4 ratio, were placed in an erlenmeyer flask and maintained at 30rpm for 1 hour in a temperature-controlled bath at 65ºC. The mixture was filtered under vacuum and cooling at 10ºC to allow for the separation of the solvent in two phases. Carotenoids composition, determined by HPLC, has indicated a β-carotene concentration about 12 times greater in the lower phase than in the upper phase. The profile of the carotenoids in the denser phase is quite similar to that of raw buriti oil, and the concentration of total carotenoids is 40% higher than that of the original raw oil, making the ethanol-based process particularly attractive for industrial applications.

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Pereskia aculeata Mill. (Ora-pro-nóbis) is a native cactaceae from tropical America, whose leaves have high protein content. In Brazil it is found in all territorial extension between the states of Bahia and Rio Grande do Sul. Most studies have focused on chemical characterization of the leaves of this specie. The objective was to assess the carotenoids profile and the total polyphenols present in the fruits of P. aculeate. Carotenoids were determined by HPLC-PAD (high performance liquid chromatography - photodiode array detector), total polyphenols were determined by Folin-Ciocalteu and vanillin methods. Trans-β-carotene was the main carotenoid, followed by α-carotene, lutein and other minor carotenoids. It was found 64.9 ± 1.1 mg.100g-1 of gallic acid equivalent, 14.8 ± 0.2 mg.100g-1 of catechin equivalent. Carotenoid identification of P. aculeate fruits are presented here by the first time and indicate that these fruits can be researched as source of bioactive substances, especially antioxidant and provitamin A carotenoids.

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We assessed trends in dietary intake according to gender and education using repeated cross-sectional, population-based surveys conducted between 1993 and 2012 in Geneva, Switzerland (17,263 participants, 52.0 ± 10.6 years, 48% male). In 1993-1999, higher educated men had higher monounsaturated fatty acids (MUFA), carotene and vitamin D intakes than lower educated men, and the differences decreased in 2006-2012. In 1993-1999, higher educated women had higher fiber, iron, carotene, vitamin D and alcohol intakes than lower educated women, and the differences decreased in 2006-2012. Total energy, polyunsaturated fatty acids, retinol and alcohol intakes decreased, while mono/disaccharides, MUFA and carotene intake increased in both genders. Lower educated men had stronger decreases in saturated fatty acid (SFA) and calcium intakes than higher educated men: multivariate-adjusted slope and 95% confidence interval -0.11 (-0.15; -0.06) vs. -0.03 (-0.08; 0.02) g/day/year for SFA and -5.2 (-7.8; -2.7) vs. -1.03 (-3.8; 1.8) mg/day/year for calcium, p for interaction <0.05. Higher educated women had a greater decrease in iron intake than lower educated women: -0.03 (-0.04; -0.02) vs. -0.01 (-0.02; 0.00) mg/day/year, p for interaction = 0.002. We conclude that, in Switzerland, dietary intake evolved similarly between 1993 and 2012 in both educational groups. Educational differences present in 1993 persisted in 2012.

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Carotenoid polyenes play a wide role in nature and their photophysical properties make of these pigments a focus of research in photochemistry, photobiology and photomedicine. Some aspects of the singlet and triplet states and, their interaction with molecular and singlet oxygen and free radicals are briefly reviewed in this article.

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The relationship between lifestyle factors, past medical conditions, daily meal frequency, diet and the risk of 'familial' colorectal cancer has been analysed using data from a case-control study conducted in northern Italy. A total of 1584 colorectal cancer patients and 2879 control subjects were admitted to a network of hospitals in the Greater Milan area and the Pordenone province. The subjects included for analysis were the 112 cases and the 108 control subjects who reported a family history of colorectal cancer in first-degree relatives. Colorectal cancer cases and control subjects with family history were similarly distributed according to sex, age, marital status, years of schooling and social class. Familial colorectal cancer was associated with meal frequency, medical history of diabetes (relative risk, RR = 4.6) and cholelithiasis (RR = 5.2). Significant positive trends of increasing risk with more frequent consumption were observed for pasta (RR = 2.5, for the highest vs the lowest intake tertile), pastries (RR = 2.4), red meat (RR = 2.9), canned meat (RR = 1.9), cheese (RR = 3.5) and butter (RR = 1.9). Significant inverse associations and trends in risk were observed for consumption of poultry (RR = 0.4), tomatoes (RR = 0.2), peppers (RR = 0.3) and lettuce (RR = 0.3). Significant inverse trends in risk with increasing consumption for beta-carotene and ascorbic acid were observed (RR = 0.5 and 0.4 respectively, highest vs lowest intake tertile). These results suggest that risk factors for subjects with a family history of colorectal cancer in first-degree relatives are not appreciably different from recognized risk factors of the disease in the general population.

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This paper reports on the development of a simple and fast procedure for β-carotene extraction from carrots and its quantification by UV/Vis spectroscopy. Carotenoids extracted from carrots may also be used as alternative reagents for TLC (thin layer chromatography) detection of natural compounds with antioxidant properties, replacing the commercial p.a. grade β-carotene. Although this reagent had around 10% b-carotene, it proved to be as efficient for TLC analysis as the commercial p.a. grade β-carotene. This practice is a useful alternative for teaching undergraduate organic chemistry laboratory classes.

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Decoction of roots of the Amazonian palm açaí (Euterpe precatoria Mart.) is widely used by Brazilian and Peruvian people as an anti-inflammatory, to heal kidney and liver diseases and against snake bites. In this study, the antioxidant activity of extracts and flavonoids (quercetin, catechin, epicatechin, rutin and astilbin) isolated from roots and leaf stalks of E. precatoria was investigated using β-carotene in TLC plates and DPPH radical scavenging in a spectrophotometric bioassay. All extracts and flavonoids showed activity. Also, the cytotoxic activity of these extracts was evaluated by the brine shrimp (Artemia salina) larvicide bioassay and was lower than that of lapachol, used as control. The presence of flavonoids and sitosterol-3-O-β-D-glucopyranoside in the extracts can justify the use of the plant in traditional medicine.

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Yeast cell wall contains polymers glucan and mannan-protein that have received much attention with respect to their biological activities. Conventional isolation process involving treatments with hot alkali and acids cause degradation of these polymers. The aim of this paper was to study a low-degrading process for the isolation of glucan and mannan-protein from S. cerevisiae cell wall comprising physic and enzymatic treatments. Yeast cell glucan was obtained in a purity of 87.4% and a yield of 33.7%. The isolated mannan-protein presented antioxidant activity that was increased after thirty minutes of protease treatment. Antioxidant activity was determined by β-carotene/linoleate model system.

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This study quantified vitamin C, E and β-carotene in samples of fresh bee-collected pollen and correlating them with the botanical origin. Vitamin content varied between 13.5 and 42.5 µg/g for vitamin E; 56.3 and 198.9 µg/g for β-carotene and 273.9 and 560.3 µg/g for vitamin C. It was concluded that the botanical origin and collecting season influenced the vitamin contents. There is a relationship between the vitamins and its botanical origin: Raphanus sp and Macroptilium sp, Mimosa caesalpineafolia with β-carotene; Raphanus sp, Eucalyptus sp, Macroptilium sp, Mimosa caesalpineafolia with vitamin E and Anadenanthera sp, Arecaceae type and Philodendron sp with vitamin C.

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Six known alkaloids iboga type and the triterpen α- and β-amyrin acetate were isolated from the roots and stems of Peschiera affinis. Their structures were characterized on the basis of spectral data mainly NMR and mass spectra. 1D and 2D NMR spectra were also used to unequivocal ¹H and 13C chemical shift assignments of alkaloids. The ethanolic extract of roots, alkaloidic and no-alkaloidic fractions and iso-voacristine hydroxyindolenine and voacangine were evaluated for their antioxidative properties using an autographic assay based on β-carotene bleaching on TLC plates, and also spectrophotometric detection by reduction of the stable DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical.

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This study evaluated the stability of vitamins C, E and β-carotene in six samples of bee pollen after their process, and in a one-year period of storage. After the pollen's process, there was a 67.1% increase for vitamin C (p <0.05), an 18.7% loss for vitamin E and 15.6% for β-carotene. Storage in freezer was the most efficient condition for the vitamins conservation; the loss in storage at room temperature (exposed or protected from light) was similar. Vitamin E appears to be better preserved during storage when compared to vitamin C and β-carotene.