133 resultados para pigmentos carotenóides


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Química - IQ

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Pós-graduação em Ciências Biológicas (Botânica) - IBB

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Pós-graduação em Ciências Cartográficas - FCT

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Agronomia (Horticultura) - FCA

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The aim of this work was to study the physiological responses of three contrasting cultivars of sugar cane subject to water stress and rewatering, The experiment was carried out in a greenhouse, where the cultivars SP83-2847, SP80-1842 and SP81-3250 were grown in pots. The first assessment was done after 85 days of planting, then two treatments were implemented, i.e. without water stress (-D) and with water stress (+D) by withholding water for 15 days and rewatering imposed for 12 days after the stress period. Cultivars SP81-3250 and SP80-1842 showed a higher decline in the F-v/F-m ratio, leaf relative water content (RWC), leaf water potential (Psi(w)), SPAD index and photosynthetic pigments due to water deficit. Drought caused less damage in the physiology of the variety SP83-2847, and it still showed rapid recovery during rewatering, including for the stomatal conductance (gs), so this variety had better adaptation under this condition. The traits F-v/F-m, Psi(w), RWC, SPAD index and photosynthetic pigments present as potential physiological indicators in order to select tolerant sugar cane cultivars to water deficit. The trait gs is more effective in differentiating the tolerant cultivars during rewatering.

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This paper was prepared a polymorphic from of curcumin a natural bioactive compound widely used in Indian medicine in the treatment of a range of illnesses. The preparation was the polymorphic crystallization process and solvent mixtures of organic solvents in order to change the dielectric constant of the solution to obtain crystals. The crystal of curcumin has been studied and characterized by absorption spectroscopic in the infrared, X-ray diffraction powder method and by thermo analytical techniques: thermogravimetry and differential therma analysis (TG-DTA) and differential scanning calorimetry (DSC). The DSC of the pure compound (MP=180,19ºC) showed some differences compared the compound crystallized (MP=176.63ºC) in a mixture of solvents thus indicating the phenomenon of polymorphism, and TG-DTA curve of the compound crystallized showed that this was not a solvatomorphic. Finnally the techniques of X-ray diffraction technique FTIR and powder showed a structural change in the compound crystallized, profile-based graphics when compared to the pure compound, which proves that the compound crystallized it is a polymorph

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Supermarket plastic bags are produced by high density polyethylene (HDPE) and low density polyethylene (LDPE) resins. In Brazil, are produced annually around 150 plastic bags per capita. Disposed in landfills, the supermarket plastic bags prevent the passage of water by slowing the breakdown of biodegradable materials and hindering compaction of waste, according to their low degradability. This work investigated the biodegradation of PE bags containing additive oxo-biodegradable and bags without additives: buried in soil columns, exposed in a controlled environment and exposed to air. The analysis methods used to assess the changes brought in the bags with respect to microbial action and exposure time were weight loss, thickness measurement, infrared (FTIR), scanning electron microscopy (SEM) and contact angle. The results showed that the use of prodegradant agents such as oxobiodegradable additives in polyethylene bags, buried in soil for 270 days, was not efficient to accelerate the biodegradation by microorganisms. It seems that these additives have been more efficient to degrade the colored pigmentation of printed bags, under the influence of light and heat.

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Atualmente, os compostos bioativos presentes em alimentos in natura vem sendo amplamente estudados, já que cada vez mais fica comprovado sua importância para saúde do homem devido suas funções e ações biológicas. Hoje já associa-se a ingestão de frutas e vegetais e a diminuição do risco de diversas doenças, tais como câncer, inflamações, doenças cardiovasculares, degeneração macular e outras, sendo os carotenóides e compostos fenólicos alguns dos grupos de compostos bioativos aos quais são atribuídas tais ações.1As pimentas têm significativa importância nesse cenário, uma vez que desde a época do Brasil colônia, até hoje, são muito utilizadas na culinária, nas crenças, na medicina e inclusive com arma de defesa. Os compostos presentes na pimenta são utilizados como remédios para artrites (pomadas a base de capsaicina), dores musculares (emplastro ‘Sabiá’), má digestão, dor de cabeça e gastrite. O presente estudo teve como objetivo quantificar os teores de ácido ascórbico, acidez, flavonóides totais, fenólicos totais, carotenóides totais e atividade antioxidante de duas variedades mais comuns da espécie C. Baccatum: pimenta “Dedo-de-Moça” e pimenta “Cambuci”. Além disso, fez-se um estudo para analisar o efeito do cozimento versus compostos bioativos, a fim de avaliar possíveis perdas de atividade devido ao processamento das amostras. Em todos os ensaios, a pimenta Dedo-de-Moça apresentou valores maiores de todos os compostos bioativos, quando comparados aos da pimenta Cambuci. Após o cozimento em água fervente, a maioria dos compostos sofreu redução, exceto nos testes de quantificação de Flavonóides e Carotenóides, os quais demonstraram aumento na concentração após o processamento.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The determination of foliar chlorophyll content is a characteristic that interests ecophysiologists and rural producers. With consideration for practical uses as well as scientific publications, our present work aims to establish equations, for rubber tree leaves, that can convert arbitrary units of expressing chlorophyll content to the international system. Chlorophyll a (Chla), chlorophyll b (Chlb), and total chlorophyll (Chltot) were obtained from intact leaves using a portable chlorophyll detecting instrument. Leaves from different positions on the plant, at various stages of maturity, and representing a large spectrum of pigment concentrations, were collected and analyzed in the field using the Clorofil OG Falkner ® instrument, through four evaluations in forty-five medium leaflets. At the laboratory, leaflets underwent a process of pigment extraction. They were incubated in a water-bath with dimethylsulfoxide (DMSO), dosed in molecular absorption spectrophotometer, and converted into pigment content per unit of fresh weight using conventional equations. The data were evaluated according to the Pearson correlation coefficient and tested with different regression models. For all variables, the linear fit is the most adequate, with correlation coefficients (r) 0.74 for Chlb and 0.88 for Chla and Chltott.

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The determination of foliar chlorophyll content is a characteristic that interests ecophysiologists and rural producers. With consideration for practical uses as well as scientific publications, our present work aims to establish equations, for rubber tree leaves, that can convert arbitrary units of expressing chlorophyll content to the international system. Chlorophyll a (Chla), chlorophyll b (Chlb), and total chlorophyll (Chltot) were obtained from intact leaves using a portable chlorophyll detecting instrument. Leaves from different positions on the plant, at various stages of maturity, and representing a large spectrum of pigment concentrations, were collected and analyzed in the field using the Clorofil OG Falkner ® instrument, through four evaluations in forty-five medium leaflets. At the laboratory, leaflets underwent a process of pigment extraction. They were incubated in a water-bath with dimethylsulfoxide (DMSO), dosed in molecular absorption spectrophotometer, and converted into pigment content per unit of fresh weight using conventional equations. The data were evaluated according to the Pearson correlation coefficient and tested with different regression models. For all variables, the linear fit is the most adequate, with correlation coefficients (r) 0.74 for Chlb and 0.88 for Chla and Chltott .

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)