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RESUMO -O experimento foi conduzido com o objetivo de obter informações sobre a influência do estádio de desenvolvimento do fruto (época de coleta) e do tipo de congelamento sobre os componentes nutricionais e de textura da polpa de pequi (Caryocar brasiliense Camb.). Os frutos foram coletados na árvore, antes da queda natural; no chão, após a queda natural, e após a queda natural, mantidos três dias em condição ambiente. Em cada época de coleta, após a retirada da casca dos frutos, um grupo de putamens foi congelado diretamente em freezer, e outro, congelado em nitrogênio líquido, antes do congelamento em freezer. Após seis meses, foi retirada a polpa dos putamens para a análise dos teores de carotenóides totais, ß -caroteno, licopeno, vitamina A, proteínas e lipídios; teor de celulose, hemicelulose, pectinas total, cálcio ligado à parede celular e total, atividade da pectinametilesterase e poligalacturonase. Os resultados indicaram que os teores de pigmentos, lipídios, proteínas e atividade da PG aumentaram com o avanço do estádio de maturação dos frutos. Por outro lado, houve diminuição no teor da celulose com avanço do estádio de maturação, enquanto os teores de hemicelulose e cálcio não foram influenciados pela idade do fruto. O tipo de congelamento interferiu nos teores de pigmentos, maiores na polpa congelada em nitrogênio líquido, e na atividade da PG, maior na polpa congelada apenas em freezer. Por último, os resultados mostraram que os frutos coletados na árvore são nutricionalmente inferiores aos coletados após a queda natural. Termos adicionais para indexação: época de colheita, carotenóides totais, ß -caroteno, licopeno, vitamina A, proteínas, lipídios, parede celular. MATURITY STAGE OF FRUITS AND FACTORS RELATED TO NUTRITIVE AND TEXTURE CHARACTERS OF PEQUI (Caryocar brasiliense Camb.) PULPABSTRACT -The experiment was carried out with the purpose to obtain information about changes in the constituents responsible for nutritive and texture traits of pequi pulp related with harvest time and types of freezing. Fruits were collected in the tree before natural fall, in the ground after natural fall and in the ground three days after natural fall. In each harvest time, while one batch of the putamens was frozen in liquid nitrogen and afterwards stored in a freezer, another batch was frozen directly in the freezer. After six months the following analyses were performed in the pulp: contents of proteins, total carotenoid, b-carotene, licopene, vitamin A and lipids (nutritive characters); content of cellulose, hemicelluloses, total pectin, total and bound calcium, activity of polygalacturonase (PG) and pectinmethilesterase (PME) of the cell wall. The contents of pigments, lipids, proteins and activity of PG were the highest in the most advanced stages of maturation of fruits. On the other hand the content of cellulose decreased with the advanced stages of maturation whiles the content of hemicelluloses, total and bound calcium were not affected at the stages of maturation of the fruits. The types of freezing...

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Acrocomia aculeata is an oil producing tropical palm tree with exceptional potential for producing biofuel.As the propagation of this species is often difficult because of its pronounced seed dormancy, the present work examined the morphology and the anatomy of zygotic embryos and seedlings during in vitro germination. Embryos were put in MS media supplemented with organic compounds and cultivated in the dark at 30°C for 20 days. The dry weights, lengths, and diameters of the cotyledonary petioles, haustoria, roots, ligules, and leaf sheaths of embryos obtained from mature seeds and seedlings removed from culture were measured every 2 days; anatomical and histochemical evaluations were performed on embryos and seedlings removed from culture after 2, 5, 8, 10, 12, and 15 days. Elongation of the embryo axis was observed to initiate after 2 days. Elongation of the cotyledonary petiole was observed starting on the fifth day; this is a morphological indication of germination that is associated with the formation of starch and raphides as well as the differentiation of tracheary elements. The growth of the cotyledon is due to increases in cell volumes as well as the development of a meristematic band peripheral to the haustorium. In spite of the fact that the radicle is less differentiated than the plumule, radicular development is precocious and the root emerges first, indicating the absence of morphological dormancy. Atrophy of the haustorium and the accumulation of phenolic compounds in subepidermal cell layers occur due to culturing conditions.