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991.
Lillian Barros Paula Baptista Daniela M. Correia Susana Casal Beatriz Oliveira Isabel C.F.R. Ferreira 《Food chemistry》2007,105(1):140-145
The chemical composition and nutritional value of five wild edible mushroom species (Agaricus arvensis, Lactarius deliciosus, Leucopaxillus giganteus, Sarcodon imbricatus, Tricholoma portentosum) commonly consumed in the Trás-os-Montes region of Northeast Portugal was determined. Chemical composition evaluation included moisture, total oil content, crude protein, ash, carbohydrates, and nutritional value determination. The macronutrient profile in general revealed that the wild mushrooms were rich sources of protein and carbohydrates, and had low amounts of fat. On the basis of the proximate analysis, it can be calculated that an edible portion of 100 g of these mushrooms provides, on average, 28 kcal (118 kJ). The analysis of fatty acid composition, performed by gas–liquid chromatography coupled to a flame ionization detector, allowed the quantification of fifteen fatty acids. Unsaturated fatty acids and, in particular, oleic and linoleic acids, were predominant. The composition in individual sugars was also determined by high performance liquid chromatography coupled to a refraction index detector, mannitol and trehalose being the most abundant sugars. 相似文献
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994.
Luis Carlos Matos José A. Pereira Paula B. Andrade Rosa M. Seabra M. Beatriz P.P. Oliveira 《Food chemistry》2007,102(3):976-983
Three monovarietal virgin olive oils obtained from olives grown under biological agricultural system, in Portugal, with different ripening stages, were studied in what concerns the parameters usually related with oxidation status (total polyphenols, tocopherols, chlorophylls and carotenoids, peroxide values, oxidative stability, specific extinction coefficients K232 and K270 and titratable acidity). A total of 18 samples were analyzed: seven from Cv. Cobrançosa (maturation indices 1–7), five from Cv. Madural (maturation indices 3–7) and six from Cv. Verdeal Transmontana (maturation indices 1–6). Oxidative stability and polyphenols profile presented high correlation coefficients. Given this high correlation, a numerical method was developed and evaluated to predict total polyphenols contents in olive oil. The method is based on the kinetic equation of the oxidation process in the presence of antioxidants and on Rancimat profiles. Total polyphenols contents obtained with this method were similar to those obtained by the Folin-Ciocalteau method. 相似文献
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996.
Jucélia Pizzetti Benincá Ana Beatriz Montanher Silvana Maria Zucolotto Eloir Paulo Schenkel Tania Silvia Fröde 《Food chemistry》2007,104(3):1097-1105
The aim of this study was to investigate the anti-inflammatory effect of the aqueous extract of Passiflora edulis forma flavicarpa Degenerer leaves in the air pouch inflammation model induced by carrageenan, histamine or substance P, in mice. An aqueous extract was prepared by infusion and lyophilized. Part of the extract was fractionated with n-butanol, resulting in the butanolic and aqueous residual fractions. The anti-inflammatory activities of the lyophilized extract and these two derived fractions were evaluated. In the inflammation induced by carrageenan, aqueous extract (100 mg/kg, i.p.), butanolic fraction (50 mg/kg, i.p.), aqueous residual fraction (100 mg/kg, i.p.) and dexamethasone (0.5 mg/kg, i.p.) inhibited the leukocyte, neutrophil, myeloperoxidase, nitric oxide, and interleukin-1 beta (IL-1β) levels (p < 0.05). The aqueous extract and butanolic and aqueous residual fractions, but not dexamethasone, decreased macrophage inflammatory protein-2 (MIP-2) levels (p < 0.05). Only dexamethasone inhibited mononuclear cells (p < 0.01). In the inflammation induced by histamine, the aqueous extract, butanolic and aqueous residual fractions, and dexamethasone inhibited total and differential leukocytes (p < 0.01). In the inflammation induced by substance P, the aqueous extract, butanolic and aqueous residual fractions, and dexamethasone also inhibited total leukocytes and mononuclears (p < 0.01). Neutrophils were only inhibited by aqueous extract, butanolic fraction, and dexamethasone (p < 0.05). In conclusion, the active principle(s) present in the P. edulis aqueous extract and its two fractions showed pronounced anti-inflammatory properties, inhibiting cell migration, proinflammatory cytokines, enzymes and mediators. 相似文献
997.
Beatriz Arizaga Andrea de Leon Natalia Burgueño Alejandro López Daniel Paz Natalia Martínez Daniel Lorenzo Eduardo Dellacassa Juan Bussi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(6):532-538
The production of several oxygenated derivatives of limonene was carried out by using orange oil and molecular oxygen as the sole initial reactants under solvent‐free conditions. Palladium–copper supported on carbon and hydrotalcite‐like compounds displayed good catalytic properties to accelerate autoxidation reactions of limonene yielding a mixture of the different oxygenated derivatives, mainly 1,2‐ and 8,9‐epoxylimonene, 1,2,8,9‐diepoxylimonene, carveol and carvone. Palladium supported on copper–magnesium–aluminium hydrotalcite displayed the best properties due to its higher catalytic activity and lifetime. The pelletized form of these catalysts can be easily recovered and reused. A reactor design combining recirculation and oxygen bubbling through a catalytic bed of the pelletized catalyst produced the highest reaction rate. Vacuum distillation of the final product mixture allowed easy separation of the 1,2/8,9‐limonene epoxides. The other required compounds, mainly carveol and carvone, were not completely separated and remained together with the other oxygenated products, such as the di‐epoxylimonene isomers. Copyright © 2007 Society of Chemical Industry 相似文献
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999.