Biblioteca do Café

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1

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Resultados da Pesquisa

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    Protein profile in arabica coffee seeds in electrophoresis gel: importance of freeze-drying
    (Associação Brasileira de Tecnologia de Sementes - ABRATES, 2022-05-13) Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Figueiredo, Madeleine Alves de; Coelho, Stefânia Vilas Boas; Vilela, Ana Luiza de Oliveira; Padilha, Lilian
    Coffee seeds are sensitive to desiccation and are used or stored with different moisture content values, which may affect the results of quality assessment. The aim of this study was to evaluate the changes in protein profile in electrophoresis gel in coffee seeds with different moisture content values under freeze-drying and without freeze-drying. Two lots of arabica coffee seeds were used, one of newly-harvested seeds and another of stored seeds. The seeds were dried to the moisture content values of 12, 15, 20, 25, 30, 35, and 40%. The physiological quality of the seeds was assessed through the germination test, electrical conductivity, and the profiles of the enzymes SOD, CAT, PO, GOT, MDH, and EST and of heat-resistant proteins. In general, there is an effect on expression of these enzymes in accordance with the presence of free water in the seeds. Moist seeds have little to no enzyme expression. The freeze-drying process allows preservation of coffee seed quality and does not change the functionality of the enzymes studied. The isoenzyme profiles of the antioxidant process in arabica coffee seeds are affected by the initial moisture content of the seeds. The freeze-drying process of the seeds ensures greater sensitivity in detection of the expression of these isoenzymes.
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    Endo-β-mannanase enzyme activity in the structures of Coffea arabica L. seeds under different types of processing and drying
    (Universidade Federal de Santa Maria, 2018) Ferreira, Valquíria Fátima; Ricaldoni, Marcela Andreotti; Rosa, Sttela Dellyzete Veiga Franco da; Figueiredo, Madeleine Alves de; Coelho, Stefânia Vilas Boas; Fantazzini, Tatiana Botelho
    Enzymes play a fundamental role in degradation of molecules during seed germination, development, and deterioration. Endo- β-mannanase is one of the main enzymes responsible for hydrolysis of mannans in the endosperm during germination of coffee seeds through its action in hydrolytic degradation of cell walls and in weakening the structures of the endosperm that surround the embryo, allowing radicle emergence. The aim of this study was to determine the activity of the endo-β-mannanase enzyme in the structures of coffee seeds for the purpose of assessing the relationship between this activity and the physiological quality of the seeds under different processing and drying methods. Coffea arabica L. fruit in the cherry maturity stage was subjected to three different types of processing: natural (seeds maintained in the fruit itself), fully washed (fruit pulped mechanically and the seeds demucilaged by fermentation in water), and semi-washed or demucilaged (both fruit pulp and mucilage removed mechanically); and two methods of drying: slow drying (suspended screen) in the shade, and rapid drying in mechanical dryer at 35°C to a moisture content of 11±1%. After processing and drying, the physiological quality of the seeds was evaluated through the germination test, and endo-β-mannanase enzyme activity was quantified. Coffee seeds submitted to natural processing have lower physiological performance, as well as greater deterioration and greater activity of the endo-ß-mannanase enzyme. Removal of mucilage during fully washed and semi-washed processing of coffee seeds reduces the activity of the endo-ß-mannanase enzyme and lowers deterioration, especially after faster drying. The enzyme endo-ß-mannanase is efficient in studying of the effects of processing and drying on coffee seeds, and can be evaluated in whole seeds, endosperms or embryos.