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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Drying of arabica coffee and its effect on the gene expression and activity of enzymes linked to seed physiological quality(Editora da Universidade Estadual de Maringá - EDUEM, 2023) Carvalho, Mayara Holanda de; Rosa, Sttela Dellyzete Veiga Franco da; Coelho, Stefânia Viias Boas; Guimarães, Cristiane Carvalho; Martins, Rayana de Sá; Clemente, Aline da Consolação Sampaio; Paiva, Luciano VilelaThe reduced longevity of coffee seeds has been attributed to their sensitivity to desiccation. Studies related to gene expression and enzyme activity in coffee seeds under drying are important for understanding the effects of drying on their physiological quality. The aim of this study was to investigate the molecular aspects of seeds under different drying methods and associate them with physiological quality. Coffee seeds with different water contents were dried both slowly and rapidly. Enzymatic activity was analysed, as well as the expression of genes that encode the enzymes superoxide dismutase, catalase, peroxiredoxins, isocitrate lyase, and endo-ß-mannanase. There was a significant effect of drying speed and final water content on enzyme activity and on the expression of the different genes analysed. In seeds under rapid drying, there was greater expression of the genes that encode the enzymes catalase and endo-ßmannanase. Greater expression of the 1 CYS PRX and SOD genes and greater activity of the ICL isoenzymes were found in seeds with superior physiological quality, but greater activity of the endo-β-mannanase and CAT enzymes occurred in seeds with lower physiological quality.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 Evaluation of the behavior of coffee stored in cooled and natural environments(Universidade Federal de Lavras, 2023-01-11) Andrade, Ednilton Tavares de; Rezende, Renan Pereira; Borém, Flávio Meira; Rosa, Sttela Dellyzete Veiga Franco da; Rios, Paula de Almeida; Oliveira, Filipe da Silva deThe market value of coffee is strongly influenced by loss of quality, which makes storage one of the main steps in the entire production chain. The finite element method (FEM) and computational fluid dynamics (CFD) are numerical and computational techniques that facilitate the simulation of agricultural product storage systems. Computational modeling satisfactorily represents real experimentation, simplifies decision-making, and reduces costs. This study aimed to analyze mocha coffee storage for 6 months in a cooled environment with temperatures between 15 and 18 °C and in a natural environment. The water content, bulk density, specific heat, thermal conductivity, and thermal diffusivity were determined and colorimetry and sensory analysis were applied to compare initial and final samples of the product after storage. It was found that the water content and specific heat were the only properties that presented significant changes. Through sensory analysis, it was observed that the quality of the coffee was the same for both systems. A computational model was developed to simulate the heat transfer process during storage. The comparison of the simulation results with the experimental results for the temperature distribution in the grain mass showed overall mean relative errors of 2.34% for the natural environment and 5.74% for the cooled environment.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 Identification of physiological analysis parameters associated with coffee beverage quality(Editora UFLA, 2020) Freitas, Marcella Nunes de; Rosa, Sttela Dellyzete Veiga Franco da; Pereira, Cristiane Carvalho; Malta, Marcelo Ribeiro; Dias, Carlos Tadeu dos SantosThe demand for high-quality coffee among consumers has generated a great deal of interest among producers in serving this market. Parameters for physiological analyses that can be associated with aspects of sensory analyses of coffee can ensure more reliable results for coffee quality assessments. The aim of this study was to investigate the potential of physiological analyses in determining coffee quality through multivariate analysis. Several samples from coffee bean/seed lots were placed in cold storage at 10 °C, after which the sensory quality, physiological quality, and chemical characteristics of the beans were evaluated before storage and after three and six months of storage. The variables of physiological quality in the coffee beans were correlated with sensory analysis parameters. The viability of coffee embryos revealed by the tetrazolium test results were positively correlated with the final sensory analysis score. There was a correlation of root dry matter, hypocotyl dry matter, potassium leaching, and electrical conductivity with the sensory attributes that comprise the final sensory analysis score for the coffee beans. Variation in the final sensory analysis score was explained up to 97.14% by the variables radical emergence (r2 = 2.27%), strong normal seedlings, (r2 = 0.56%), seedlings with expanded cotyledonary leaves (r2 = 0.53%), tetrazolium test results (r2 = 91.54%), and potassium leaching (r2 = 2.24%). More studies are required to enable the use of physiological analyses to complement sensory analysis.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 Cold coffee seeds storage with different water content(Editora UFLA, 2021) Penido, Amanda Carvalho; Reis, Venícius Urbano Vilela; Rezende, Édila Maria de; Rocha, Debora Kelli; Oliveira, João Almir; Rosa, Sttela Dellyzete Veiga Franco daCoffee seeds are classified as intermediate because they have low tolerance to desiccation and low longevity. Consequently, moisture control and storage conditions are important factors in maintaining the physiological quality of these seeds. Thus, the objective in this work was to evaluate the water content effect on coffee seed longevity. Seeds of five Coffea arabica cultivars from the 2016/2017 crop were used. Part of the harvested seeds was dried in the shade until reach 12% moisture and the other part did not go through drying process, remaining with 40% water content. The seeds were stored in a cold chamber at 10 ºC for a period of nine months, and the physiological quality was evaluated every three months by germination, root protrusion, seedlings with expanded cotyledonary leaves, seedling dry mass and enzymatic analysis of catalase enzymes and superoxide dismutase. Regardless of the cultivar, wet seeds coffee storage provides better maintenance of physiological quality for up to nine months. Seedling vigor is reduced throughout the storage period, regardless of seed water content.