Brazilian Archives of Biology and Technology
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12090
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Item Dynamic Behavior of Coffee Branches: an Analysis Using the Finite Element Method(Instituto de Tecnologia do Paraná - Tecpar, 2024-01-12) Melo Junior, Wellington Washington Andrade de; Santos, Fábio Lúcio; Scinocca, Francisco; Rosa, Pablo Antunes da; Magalhães, Ricardo RodriguesThe use of computational simulation techniques is an important tool for the coffee harvesting issues, particularly the finite element method. The method is widely used in the structural analysis of agricultural machinery, as well as in the analysis of the stresses and vibrations of coffee branches and peduncles during the harvesting process. The present study aimed to develop three-dimensional finite element models of the plagiotropic branches of the Catuaí Vermelho variety of Arabica coffee in different positions along the orthotropic branches of the plant; considering high-fidelity models. Additionally, by considering the branches’ experimental properties (physical-mechanical), the natural frequencies and vibration modes of the branches were determined by means of computer simulations. First, the geometric properties of the coffee branches were obtained by means of two images taken using a professional camera to obtain the input data of the virtual simulation. For the mechanical properties, it was used a semi-analytical digital scale, to obtain the mass of the specimens. The modulus of elasticity was determined using a universal testing machine. The variability in the simulated natural frequencies could be identified, which was on the order of 30% for the first frequency, regardless of the position of the branch in the plant. These values were lower for the other frequencies. Linear regression fits showed a coefficient of determination, and correlation tests were used to verify the relationship between the values obtained numerically and experimentally, which were validated by using experimental data using the modal analysis techniques.Item Nitrogen metabolism in coffee plants subjected to water deficit and nitrate doses(Instituto de Tecnologia do Paraná - Tecpar, 2023-03-24) Rocha, Brunno César Pereira; Martinez, Hermínia Emília Prieto; Ribeiro, Cléberson; Brito, Danielle SantosNitrogen uptake is essential for coffee growth and development, resulting in important effects on the biomass and final crop yield. Thus, like most nutrients, nitrogen is absorbed by the roots using water as a mean of transport, so that water stress and nitrogen can directly and indirectly affect various physiological processes. The aim of this paper was to evaluate the nitrogen metabolism in young plants of four varieties of coffee trees (Coffea arabica L.) submitted to water deficit (WD) and nitrogen supply. We have done a triple factorial (2 x 4 x 4) experiment entirely randomized. The plots received combinations of high or low N doses (7mmol/L and 2.8 mmol/L NO3 -), four water potentials (0; -0.4; -0.8; and -1.6 Mpa), and four varieties (Mundo Novo IAC379-19, Acauã F6 of IBC - PR 82010, Catuaí Vermelho IAC 44, and Catuaí Amarelo IAC 62). One hundred and forty days after the I of the experiment (140 days after the beginning of N stress and 82 days after the beginning of WD stress) the activity of the enzymes nitrate reductase (NR) and glutamine synthetase (GS), concentration of nitrate, free proline, amino acids (TAA), and total proteins were determined in samples of leaf and root tissues. There were differences between varieties independently of WD and N dose for leaf NR, being ‘Acauã’ the cultivar that presented the highest and ‘Catuaí Vermelho’ the lowest value to this trait. The WD promoted an increase on the proline concentration in the roots. With low N dose, the activity of GS presented linear increases in response to WD. It was concluded that in young coffee plants under WD, proline can be involved in the osmotic adjustment, having its synthesis in the roots increased. Under WD, plants with good nitrogen nutrition presented larger leaf concentration of soluble amino acids and total soluble proteins. The varieties studied do not present differentiated responses to WD.Item Development of Adsorbent Materials Using Residue from Coffee Industry and Application in Food dye Adsorption Processes(Instituto de Tecnologia do Paraná - Tecpar, 2022-11-11) Castro, Luiz Eduardo Nochi de; Battocchio, Débora Alessandra Jones; Ribeiro, Leomara Floriano; Colpini, Leda Maria SaragiottoThe aim of this study was to develop an adsorbent from coffee husk, residue from the coffee industry by different activation methods and to evaluate its application in the treatment of effluent containing synthetic Ponceau 4R dye. The activations were with phosphoric acid and zinc chloride, then the samples were characterized in terms of physical and chemical composition, structure and morphology, thermal behavior and kinetic and thermodynamic study. Regarding the characterization of the material, the activation with phosphoric acid showed porous morphology and a high surface area (429.7 m2 g-1) and with the kinetic study it was possible to obtain an equilibrium time of 60 min and dispersion according to Elovich kinetics (R2 = 0.96 and RMSE < 0.24). According to the experimental design, the adsorptive capacity can be evaluated with the significant result (qe = 19.87 mg g-1) under the conditions of 90 min of the adsorption process and at the concentration of 2 g L-1 of adsorbent. In relation to the equilibrium study the Langmuir model fit the data with coefficient of determination of R2 = 0.84. Finally, the Ponceau 4R dye adsorption process using coffee husks as an activated carbon was thermodynamically favorable through the negative Gibbs free energy and positive entropy (+0.022 kJ mol-1 K-1). Therefore, the use of coffee husk as activated carbon proved to be a favorable material for Ponceau 4R dye adsorption.Item Enzyme Production by Induratia spp. Isolated from Coffee Plants in Brazil(Instituto de Tecnologia do Paraná - Tecpar, 2020) Monteiro, Mônica Cristina Pereira; Tavares, Dérica Gonçalves; Nery, Eduardo Mateus; Queiroz, Marisa Vieira de; Pereira, Olinto Liparini; Cardoso, Patrícia GomesEndophytic fungi belonging to the genus Muscodor now transferred to Induratia are known producers of bioactive volatile organic compounds (VOCs) with many industrial applications. However, the members of this genus have rarely been reported to produce non-volatile metabolites including enzyme. Enzymes of the endophytes are degraders of the polysaccharides available in the host plants and the knowledge of enzyme production by Induratia spp. may provide insights into their possible biotechnological applications. The aim of this study was to evaluate the activity of amylase, cellulase, lipase, pectinase, phytase, protease, endo β-1,4 glucanase and exo β-1,4 glucanase enzymes produced by fungi of the species Induratia coffeana, Induratia yucatanensis and Induratia sp. isolated from organic coffee plants. All Induratia spp. were able to produce the extracellular enzymes cellulase, pectinase, protease, and phytase. Eight fungi were able to produce lipase and four produced amylase. The specific activity of endo β-1, 4 glucanase and exo β-1,4 glucanase enzymes were detected for 9 and 8 endophytic fungi, respectively. This work demonstrated for the first time, the array of enzymes produced by Induratia spp. isolated from Coffea arabica in organic systems in Brazil.Item Characterization of Roasted Coffea arabica Species by the Relationship Between Caffeine and Diterpenes Contents(Instituto de Tecnologia do Paraná - Tecpar, 2020) Zanin, Rodolfo Campos; Kitzberger, Cíntia Sorane Good; Benassi, Marta de ToledoCommercial roasted and ground coffees are usually blends of Coffea arabica and Coffea canephora. Considering the differences in price and sensory characteristics between these two species, the identification of the presence of each species in commercial blends is of great interest. The aim of this study was to describe typical profiles of caffeine and diterpenes (kahweol and cafestol) contents and the ratios among these compounds to support the characterization of Coffea species in roasted coffees. 32 good cup quality Brazilian C. arabica coffees (from coffee quality contests) produced using different postharvest treatments were studied. All analysis were performed by HPLC. Higher ranges were observed in diterpene contents – kahweol varied from 1.75 to 10.68 g/kg (coefficient of variation of 510%) and cafestol from 1.76 to 9.66 g/kg (449%) – than caffeine, that varied from 5.1 to 16.2 g/kg (coefficient of variation of 218%). Wide ranges of the kahweol/cafestol ratio (0.63 to 2.77) and the caffeine/kahweol ratio (0.84 to 5.15) were also observed. Hence it was proposed the additional use of a new parameter, the ratio of caffeine/sum of diterpenes (kahweol + cafestol) that presents values from 0.54 to 2.39. The results indicated that the combined use of these parameters could be a potential tool for discriminating Coffea species in blends of roasted and ground coffee. It was proposed as potentially indicative of C. arabica: values of kahweol/cafestol ratio above 0.50, associated with caffeine/kahweol ratio lower than 5.50 and caffeine/sum of diterpenes ratio lower than 2.50.