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Item Steps of cryopreservation of coffee seeds: physiological responses and antioxidant systems(Universidade Federal de Santa Maria, 2023-08-21) Souza, Ana Cristina de; Costa, Marina Chagas; Figueiredo, Madeleine Alves de; Pereira, Cristiane Carvalho; Coelho, Stefânia Vilas Boas; Vilela, Ana Luiza Oliveira; Pereira, Diego de Souza; Rosa, Sttela Dellyzete Veiga Franco daThe cryopreservation of plant germplasm at ultralow temperatures is an alternative technique for the long-term storage of seeds of the genus Coffea sp. However, for this technique to be successful, cell integrity must be maintained at all stages of the process on the basis of scientific research. The present study investigated validated cryopreservation protocols for Coffea arabica L. seeds and evaluate the effects on the physiological and biochemical characteristics of the seeds at each stage of the process. Seeds were dried on silica gel or with saturated saline solution, precooled or not in a biofreezer, immersed in nitrogen, and reheated in a water bath. After each of these steps, the physiological and biochemical quality of the seeds was determined. Pre-cooling is a step that can be dispensed with in the cryopreservation of Coffea arabica seeds, direct immersion in liquid nitrogen being more indicated. Coffea arabica L. seeds tolerate cryopreservation after rapid drying in silica gel up to water contents of 17 or 20% (wb), with greater survival at 17%. The enzyme activities of catalase, polyphenol oxidase and peroxidase are indicators of the quality of C. arabica L. seeds subjected to cryopreservation.Item 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, LilianCoffee 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.Item Trolox equivalent antioxidant capacity of Coffea arabica L. seeds(Editora UFLA, 2022-08-08) Ferreira, Iara Alves; Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Coelho, Stefânia Vilas Boas; Ricaldoni, Marcela Andreotti; Costa, Marina ChagasThe causes of the low desiccation tolerance and low longevity of coffee seeds have not yet been fully elucidated, and a full understanding of their complex physiology is of great interest. Among several alternatives, the loss of antioxidant capacity in seeds may be related to their rapid loss in quality during storage. The objective of this study was to determine the total antioxidant capacity of coffee harvested at different ripeness stages before and after the storage of seeds with different water contents and to relate antioxidant capacity to physiological quality. Seeds in the greenish-yellow or cherry stages, recently harvested or stored for nine months at 10 °C with 40, 30, 20 and 12% water content (wet basis - wb), were submitted to physiological and biochemical quality evaluations, and the Trolox equivalent antioxidant capacity (TEAC) was determined. The germination and root protrusion of coffee seeds from greenish-yellow and cherry fruits were not affected by drying, but seeds harvested at physiological maturity had greater vigor when the moisture content was lower. The quality of coffee seeds decreased during storage, and this decrease was greater in seeds stored with higher water contents. Coffee seeds in the greenish-yellow stage had a higher antioxidant capacity than those in the cherry stage when recently harvested, but there was a substantial reduction in this capacity during storage at both maturation stages. Coffee seed deterioration is related to a reduction in antioxidant capacity, and the isoenzymatic profiles of the antioxidant process are little affected by the seed maturation stage. The deterioration of coffee seeds during storage is related to a reduction in their total antioxidant capacity, regardless of their maturation stage, being more pronounced in the greenish-yellow stageItem Antioxidant and antimicrobial activity of cathode and anode water in Coffea arabica L. seeds(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2021) Vilela, Ana Luiza Oliveira; Rosa, Sttela Dellyzete Veiga Franco da; Coelho, Stefânia Vilas Boas; Fávaris, Nathália Aparecida Bragança; Fantazzini, Tatiana Botelho; Baute, Júlia LimaSeed deterioration induces the formation of free radicals and proliferation of microorganisms, but the application of external antioxidants may lessen these effects. The aim of this study was to investigate the antioxidant and antimicrobial activity of cathode and anode water on the physiological quality and health of Coffea arabica L. seeds. Part of the seeds were soaked in cathode water and the other part in anode water for periods of 1, 6, 12, 24, and 36 hours. The physiological quality of the seeds was evaluated by the germination test and tetrazolium test, and seed health by the Blotter test. Analysis of variance and Pearson correlation analysis were performed on the data for all the response variables. Soaking in cathode water or anode water up to 24 hours improves the physiological quality of coffee seeds. Anode water has a beneficial effect on the health of coffee seeds, reducing the incidence of Fusarium spp., Penicillium spp., Cladosporium spp., and Alternaria spp. after one hour of soaking and of Aspergillus spp. after six hours. Soaking in cathode water for a period of one hour leads to a reduction in the fungi Aspergillus spp., Fusarium spp., Cladosporium spp., and Alternaria spp., and reduction in Penicillium spp. after six hours.Item Physiological, biochemical, and ultrastructural aspects of Coffea arabica L. seeds under different cryopreservation protocols(Editora UFLA, 2021) Figueiredo, Madeleine Alves de; Rosa, Sttela Dellyzete Veiga Franco da; Ricaldoni, Marcela Andreotti; Pereira, Cristiane Carvalho; Coelho, Stefânia Vilas Boas; Silva, Luciano CoutinhoCryopreservation is a technique that may potentially conserve the germplasm of species of the Coffea genus for an indeterminate time. The aim of this study was to evaluate the physiological, biochemical and ultrastructural characteristics of cryopreserved seeds of Coffea arabica L., cultivar Catucaí amarelo IAC 62, which was subjected to different protocols regarding dehydration, precooling, cooling, rewarming and cathode water use. According to each protocol, the seeds were subjected to fast or slow drying to moisture contents of 17 or 20% (wet basis), cooled in different ways, and then immersed in liquid nitrogen for 24 hours. Different rewarming times in a water bath were also used. Physiological, biochemical and ultrastructural analyses were performed on the seeds after the cryopreservation steps. Moisture content at a 17% wb is the key factor for the cryopreservation of Coffea arabica L. seeds, which have better physiological quality and better preserved cell structures. Precooling of coffee seeds before immersion in liquid nitrogen does not provide advantages compared to direct immersion. The rewarming times tested (2, 4, and 6 minutes) and cathode water use did not cause changes in the physiological and biochemical quality or in the cell structures of Coffea arabica L. cryopreserved seeds. The pattern of cell structure observed in all seeds indicates that the damage from cryopreservation is less drastic in the cells of the embryos than in those of the endosperm, with the latter less tolerant to the stresses of dehydration, precooling, and rewarming.Item Ultrastructural damage in coffee seeds exposed to drying and to subzero (°C) temperatures(Editora UFLA, 2020) Coelho, Stefânia Vilas Boas; Rosa, Sttela Dellyzete Veiga Franco da; Clemente, Aline da Consolação Sampaio; Lacerda, Laura Nardelli Castanheira; Silva, Luciano Coutinho; Fantazzini, Tatiana Botelho; Ribeiro, Fernando Augusto Sales; Castro, Elisa de MeloDuring drying and freezing, protective mechanisms act to maintain seed physiological quality. Some of these mechanisms contribute to the integrity of cell membranes. The damage caused to cell membranes due to cell stress can be seen in ultrastructural studies, comparing these results to those of physiological evaluation. The aim of this study was to investigate ultrastructural changes in endosperm cells of coffee seeds brought about by drying and by exposure to low temperatures. Seeds of Coffea arabica were dried in silica gel to moisture contents of 40, 20, and 5 % (wb) and brought to equilibrium at temperatures of 10, -20, and -86 oC. Germination, vigor, and tetrazolium tests were performed for evaluation of seed physiological quality. Ultrastructural damage was analyzed by scanning electron microscopy. Coffee seeds with 40% moisture content have whole, swollen, and expanded cells, with a filled lumen and without signs of damage. The physiological and ultrastructural quality of seeds exposed to below zero temperatures with 40% moisture content is compromised. They have null germination and empty cells, indicating leakage of cell content. Drying of coffee seeds leads to uniform contraction of inner cell content. Drying of coffee seeds to 5% moisture content leads to intense contraction of cell volume, with physiological and ultrastructural damage.Item Cryopreservation in Coffea canephora Pierre seeds: slow and fast cooling(Editora UFLA, 2018-11) Coelho, Stefânia Vilas Boas; Rosa, Sttela Dellyzete Veiga Franco da; Fantazzini, Tatiana Botelho; Baute, Júlia Lima; Silva, Luciano CoutinhoCoffee is one of the main agricultural commodities in the country, and it is important to conservation of plant material for breeding programs. Cryopreservation is a promising alternative for preserving in the long-term the germplasm of species considered recalcitrant. However, studies should be performed to achieve maximum survival of seedlings after immersion in liquid nitrogen. The objective of this work was to find a cryopreservation protocol for storing seeds of Coffea canephora, studying two methods of cryopreservation, slow and fast cooling. Seeds were subjected to drying in silica gel up to the water content of 0.25 g g -1 . In the first experiment, dried seeds were subjected to treatments of slow cooling at speeds of -1 oC min -1 ,-3 oC min -1 and -5 oC min -1 until the end temperatures of -40 oC, -50 oC and -60 oC, by means of a bio freezer and subsequently immersed in liquid nitrogen. In the second experiment, the best result was selected of the first experiment and compared with the rapid cooling, in which dried seeds, with 0.25 g g -1 of water content, were immersed directly into liquid nitrogen. Physiological and biochemical alterations occurring in the seeds after cryopreservation were evaluated. Coffea canephora seeds respond better to cryopreservation by rapid cooling, when compared to slow cooling. Drying, one of the cryopreservation steps does not affect the viability of Coffea canephora Pierre seeds, when these seeds are dried to 0.25 g g -1 of water content. Catalase and esterase enzymes are good biochemical markers for cryopreserved coffee seeds and their activity is greater in larger seed physiological quality.Item 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 BotelhoEnzymes 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.