Agroquímica

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http://repositorio.ufes.br/handle/10/17376

Programa de Pós-Graduação em Agroquímica

Centro: CCENS
Telefone: (28) 3552 8731
URL do programa: http://www.agroquimica.alegre.ufes.br/pos-graduacao/PPGAQ

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Agora exibindo 1 - 20 de 54

Adsorção de cromo hexavalente por hidróxido de alumínio amorfo em meio aquoso: isotermas e termodinâmica
(Universidade Federal do Espírito Santo, 2022-02-15) Oliveira, Sara de Jesus; Burak, Diego Lang; https://orcid.org/0000000267583517; http://lattes.cnpq.br/2501042964619476; https://orcid.org/0000000271299690; http://lattes.cnpq.br/4230219901556586; Anastácio, Simone Aparecida Fernandes; https://orcid.org/0000-0002-7030-6748; http://lattes.cnpq.br/0532528200582514; Neves, Mirna Aparecida; http://lattes.cnpq.br/4696981882395783
The presence of potentially toxic metals in the environment lethally affects the ecosystem, which means that environmental responsibility actions have being developed in order to minimize the damage caused by those elements. Therefore, this study has been evaluated the removal of hexavalent chromium by amorphous aluminium hydroxide in aqueous media under experimental temperature conditions of 25, 45 and 55 °C, and concentrations of adsorbate ranging from 30 to 300 mg L -1 . The adsorbate has been synthesized by the precipitation method, and characterized by the diffuse reflectance in near infrared (NIR) method, obtaining three significant peaks that described the product. By using partition coefficient (Kp), it was possible to establish the saturation point on the adsorbate active sites. The equilibrium isotherms, based on the determination coefficient (R2 ) indicated the adjustment order: Sips> RedlichPeterson> Koble-Corregan> amorphous aluminium hydroxide Langmuir> Jovanivich> Freundlich. The negative values of (∆G°) and enthalpy (∆H°) indicated that the reaction is spontaneous and the process is exothermic, respectively. The maximum adsorption capacity (qmax) of the amorphous aluminium hydroxide was 77,52 mg g-1 , which proves the removal efficiency in the hexavalent chromium in aqueous media.
Adsorção de leuco verde malaquita em biocarvão sintetizado a partir de coroas de abacaxi
(Universidade Federal do Espírito Santo, 2020-06-23) Santos, Cynthia Pereira dos; Profeti, Demetrius; https://orcid.org/0000-0003-4565-3331; http://lattes.cnpq.br/5030262115789096; Profeti, Luciene Paula Roberto; https://orcid.org/0000-0001-6280-2410; http://lattes.cnpq.br/6517975282316378; https://orcid.org/0000-0002-2945-8299; http://lattes.cnpq.br/3990396900334723; Passos, Renato Ribeiro; https://orcid.org/0000-0001-7730-748X; http://lattes.cnpq.br/3882320619443256
Lignocellulosic biomass from agroindustrial waste have been used as a precursor in the synthesis of biochar. The biochar can be applied as an adsorbent material for the adsorption process, making this process more viable and inexpensive than the process with the activated carbon adsorbent. In this study, the biochar synthesized from pineapple crowns, which are considered rejects, was used as an adsorbent material in the adsorption of leucomalachite green in aqueous media. This dye is an organic compound resulting from the reduction of malachite green dye in alkaline solutions, which has toxic, carcinogenic and even mutagenic effects. The biomass (in natura)was characterized with thermogravimetric analysis techniques (TGA/DTG), scanning electron microscopy coupled with X-ray dispersive energy spectroscopy (SEM/EDX), % ash determination, humidity, and soluble and insoluble lignin content. The biochar, was characterized by the determination of zero-point charge (pHzpc), TGA/DTG, X-ray diffraction (XRD) and SEM/EDSanalyses. The results showed the physical and chemical properties of the material, as well as the surface characteristics and the compounds present in the biomass in natura and in the biochar. In the study of adsorption of leucomalachite green, performed in a batch test, was determined that the Sips isotherm model best fitted the adsorption equilibrium, since it presented the highest value of the determination coefficient (R2= 0.957), with maximum adsorption capacity of 4.509 mg g-1 . The equilibrium was reached in 90 minutes following the kinetic model of pseudosecond order. The activation energy of the process was determined by means of the Arrhenius equation (34.15 kJ mol-1 ). The thermodynamic study of the process showed that the adsorption was endothermic and spontaneous
Análise da composição química e de resíduo de glifosato em amostras de grãos de café Conilon
(Universidade Federal do Espírito Santo, 2021-03-05) Peixoto, Priscilla Moreira Curtis; Tomaz, Marcelo Antonio; https://orcid.org/0000000253070219; http://lattes.cnpq.br/7116075671588859; https://orcid.org/0000000290604187; https://orcid.org/0000-0002-9060-4187; Osorio, Vanessa Moreira; https://orcid.org/0000-0001-5156-4568; http://lattes.cnpq.br/3282723304057244; Parreira, Luciana Alves; https://orcid.org/0000-0001-7041-9999; http://lattes.cnpq.br/0824035845605716; Colodetti, Tafarel Victor; https://orcid.org/0000-0002-9233-5988; http://lattes.cnpq.br/5870736853541181
The risk of food contamination by pesticides has generated much concern to the public. Glyphosate-based herbicides are first in the pesticide marketing ranking in Brazil and is the most widely used form of weed control in coffee plantations. The objective of this work was to analyze volatile and nonvolatile compounds and the presence of glyphosate residue in Conilon coffee bean samples. The experiment was carried out in two coffee plantations conilon, one located in the district of Estrela do Norte, municipality of CasteloES, where the herbicide glyphosate was applied, and the other located in Lagoa Seca, rural area of the municipality of Alegre-ES, where the herbicide was not applied. The split plot scheme, 2 x 4, was used in IHD, with three replications. The plot factor corresponded to the two types of coffee samples used, being grains with and without defects. The subplot factor corresponded to the four periods in which the grains were harvested after glyphosate application in a single dose in the experimental field, and the harvest was performed at 15, 30, 45 and 60 days after herbicide application. In the experimental field that did not receive glyphosate application, samples were collected for descriptive analysis of the data, where Dic was also used, with three replications and the analysis of coffee beans with and without defects. For the analysis of volatile compounds, the hsSPME (Solide Phase Micro Extration) extraction technique and gas chromatography analysis coupled to mass spectrometry (GC-MS) were performed and for the analysis of nonvolatile compounds the high-efficiency liquid chromatography technique with ultraviolet-visible detector (HPLC-UV) was used. For the determination of glyphosate, the ELISA (Enzyme-linked immunosorbent assay) method was applied in raw coffee beans. Thirty-three volatile compounds were identified in the coffee samples of the experimental field that received glyphosate application, being the main ones of the pyrazoan classes (42.42%) and furans (15.15%), confirming the abundance of these classes in Conilon coffee. There was no trend between the values of the peak areas of the compounds of a given class depending on the type of sample (with and without defects). While in the samples of the crop that did not receive herbicide application, 22 volatiles were identified, most of them pyrazins (45.45%) and furans (18.18%) also. In grains harvested in a crop that received glyphosate application, three bioactive compounds (chlorogenic acid, caffeine and trigotein) were analyzed and for all variables significant interactions (5% probability) between the factors were observed. In grains from free crop of herbicide application, slightly higher chlorogenic acid concentrations were observed in undefective coffee samples, unlike this, higher concentrations of caffeine and trinelin were observed in defective coffee samples. The presence of glyphosate was verified in the coffees, however, it was not possible to quantify this residue, because all samples, including those collected in the greatest interval between harvest and herbicide application, exceeded the detectable and acceptable limit by buyer countries. In addition to these coffees not suitable for export, the concern with food security increases and thus, the importance of this study is evident.
Análises físico-químicas e avaliação da qualidade de Coffea canephora Pierre e Froehner cultivados no Espírito Santo
(Universidade Federal do Espírito Santo, 2018-02-23) Pinheiro, Carlos Alexandre; Pinheiro, Patrícia Fontes; Oliveira, Daniela da Silva; Fonseca, Aymbiré Francisco Almeida da; Parreira, Luciana Alves; Pereira, Lucas Louzada
The State of Espírito Santo is the leader in the production of Coffea canephora (conilon and robusta) in Brazil. C. canephora is generally cultivated at altitudes below 500 m in hot climate regions. Coffees cultivated in regions with higher altitudes pres
Análises In Silico Por 2D e 3D-QSAR e Simulações de Dinâmica Molecular em Derivados de Fosfopirazina e Fosfoguanidina na Projeção de Potenciais Inibidores da AChE da Mosca-Branca (Bemisia Tabaci)
(Universidade Federal do Espírito Santo, 2024-01-08) Souza, Fernanda Fernandes de; Paula, Heberth de; https://orcid.org/0000-0001-6197-4165; http://lattes.cnpq.br/0823599580312700; Campos, Othon Souto; https://orcid.org/0000-0002-8285-0898; http://lattes.cnpq.br/4021571191714416; https://orcid.org/0000-0002-7739-3792; http://lattes.cnpq.br/1300234028367706; Morais, Pedro Alves Bezerra; https://orcid.org/0000-0001-5501-7350; http://lattes.cnpq.br/5220285635137407; Honorio, Kathia Maria; https://orcid.org/0000-0002-6938-0676; http://lattes.cnpq.br/0438695263897215
The acetylcholinesterase (AChE) is a significant molecular target in insecticide development, but it is also found in the human body, requiring the characterization of the inhibitory profile of compounds for achieving selectivity. In this study, we employed molecular modeling and 3D-QSAR approaches to identify new AChE inhibitors for Bemisia tabaci, a common agricultural pest in tropical and subtropical crops. Molecular docking simulations and quantitative structure-activity relationship (QSAR) analysis were conducted to identify compounds with potential inhibitory activity and develop a predictive model for the activity of these new compounds. The validated model demonstrated good predictive performance with q²= 0.953 and r²= 0.999. We used the model to screen newly substituted molecules by selecting chemical groups in favorable regions of the most active molecule in the dataset, leading to the identification of promising candidates, including FS168. Molecular dynamics simulations with FS168 in complex with B. tabaci AChE revealed the stabilization and interaction of important catalytic amino acids, indicating a possible inhibition mechanism, along with a binding affinity of ΔG= -30.49 kcal/mol. The results highlight the potential of combining molecular modeling and 3D-QSAR approaches for discovering new potential AChE inhibitors for Bemisia tabaci as selective agrochemicals.
Avaliação da adsorção de Cobre(II) e Cromo(III) utilizando resíduos de mármore branco como material adsorvente não convencional e de baixo custo
(Universidade Federal do Espírito Santo, 2018-02-27) Guimarães, Tiago; Profeti, Demetrius; Brito, Gilberto Augusto de Oliveira; Profeti, Luciene Paula Roberto
The adsorption process of Cu (II) and Cr (III) ions on white marble residue was investigated by batch experiments. The studies were carried out to identify the zero charge point (PCZ) of adsorbent material, time and equilibrium concentrations of Cu (II) a
Avaliação da espectrometria no infravermelho próximo na determinação de C e N de solos da região Sul do Espírito Santo
(Universidade Federal do Espírito Santo, 2019-05-15) Vieira, Camila Fernandes; Mendonça, Eduardo de Sá; Burak, Diego Lang; Anastácio, Alexandre dos Santos
The present study aimed to investigate the predictive capacity of total organic carbon and nitrogen contents by means of near infrared reflectance spectroscopy (NIR) and its potential for use in routine soil analysis. This method presents greater agility
Avaliação do efeito antifúngico de derivados triazólicos obtidos por estratégia de hibridação molecular
(Universidade Federal do Espírito Santo, 2024-04-02) Silva, Jéssica Adalgisa Barbosa; Morais, Pedro Alves Bezerra ; https://orcid.org/0000-0001-5501-7350; http://lattes.cnpq.br/5220285635137407; https://orcid.org/0000-0003-1044-7001; http://lattes.cnpq.br/7079506819678915; Campos, Othon Souto ; https://orcid.org/0000-0002-8285-0898; http://lattes.cnpq.br/4021571191714416; Paula, Heberth de ; https://orcid.org/0000-0001-6197-4165; http://lattes.cnpq.br/0823599580312700
Black pepper has been increasingly gaining ground in the international market, accounting for 98% of Brazilian pepper exports. Espírito Santo is the most prominent state in Brazil as a black pepper producer, contributing 60% of the country's production of this spice. However, this cultivation is frequently threatened by the fungus Fusarium solani, which causes root rot in the plants. With the aim of producing new promising molecules against this pathogen, novel triazole compounds derived from natural products were synthesized. Initially, the azido-adamantane derivatives 20 and 23 were obtained and subsequently combined with alkynes derived from natural products, such as isatin, p-coumaric acid, eugenol, and thymol, to form the 1,4-disubstituted 1,2,3- triazole ring. Therefore, in this study, six molecular hybrids were designed through the copper(I)-catalyzed azide-alkyne cycloaddition reaction (CuAAC), also known as "Click Chemistry," in the presence of copper(II) sulfate pentahydrate and sodium ascorbate. The compounds 25a-b and 26a-d were characterized by 1H NMR, 13C, COSY, HMQC, HSQC, and infrared spectroscopy (FTIR) and achieved yields ranging from 20.35% to 63.66%. Molecular docking studies between the synthesized compounds and the enzyme Succinate Dehydrogenase (SDH), PDB: 1NEN, indicated that compounds 26b and 26d are potential SDH inhibitors, with hydrogen bond interactions analogous to those of the original ligand DNT, involving the amino acid residues TYR83, TRP164, and ARG31.
Biocarvão de exocarpo de sapucaia (lecythis pisonis) para a adsorção de verde brilhante
(Universidade Federal do Espírito Santo, 2024-02-23) Campos, Phelipe Augusto Carvalho; Costa, Anna Isabel Guido; https://orcid.org/0000-0003-4745-9719; Profeti, Luciene Paula Roberto; https://orcid.org/0000-0001-6280-2410; Camêlo, Danilo de Lima; Gardiman Júnior, Benvindo Sirtoli
In contemporary times, the escalating processes of industrialization and urbanization have led to watercourses' contamination by persistent organic pollutants (POPs), such as dyes, pharmaceuticals, pesticides, and aromatic hydrocarbons. Consequently, water quality is significantly compromised. To mitigate these adverse impacts, adsorption emerges as an effective and economically viable technique for treating effluents contaminated with POPs. The choice of adsorbent material is pivotal for the development of an adsorption-based decontamination process. In this context, biocarbons possess suitable characteristics as adsorbents, including high surface area, mechanical stability, and surface functional groups that act as binding sites for various organic species. With the aim of contributing to the development of sustainable technologies, this study primarily focused on the synthesis and performance evaluation of a biocarbon produced from the exocarp of Sapucaia (Lecythis pisonis) for removing the dye Brilliant Green (VB). The biocarbon synthesis, utilizing Sapucaia exocarp as a precursor, occurred at a temperature of 600°C under a nitrogen atmosphere. The synthesized material was characterized through thermogravimetric analysis (TG), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Surface area (BET and BJH) and pH at the point of zero charge (pH_PZC) were also determined. Adsorption kinetic tests for VB were conducted at temperatures of 25, 35, 45, and 55°C, using a dye solution at a concentration of 250 ppm and a pH of 7. Characterization results indicated that the synthesized material exhibited a considerable surface area and the presence of crucial surface functional groups, fundamental for successful adsorption processes. The adsorption tests revealed that the synthesized biocarbon exhibited high efficacy in removing the dye from aqueous solutions. Among the nonlinear kinetic models applied to the experimentally obtained data, the Avrami model more accurately described the VB adsorption process. According to this model, the adsorption kinetics are fractional order. Moreover, the analysis of parameters related to the Weber and Morris diffusion model indicated that the dye adsorption kinetics are controlled by more than one mechanism, supporting the Avrami model. The Sips model proved to be the most suitable for fitting the experimental equilibrium results, and thermodynamic results suggested that the adsorption process is endothermic, spontaneous, and irreversible. This study underscores the potential of biocarbon derived from Sapucaia exocarp as a promising solution for the effective removal of organic pollutants, such as Brilliant Green, from aqueous solutions. Additionally, it emphasizes the need for future research, given the limited knowledge available in the literature on this material, offering opportunities for further studies and enhancements.
Bromação e esterificação de fenóis de origem natural e avaliação do seu potencial fungicida frente ao fungo Colletotrichum musae
(Universidade Federal do Espírito Santo, 2024-06-10) Costa, Kamille Azevedo; Menini, Luciano ; https://orcid.org/0000-0003-3656-5428; http://lattes.cnpq.br/2646344913961349; https://orcid.org/0009-0005-4022-4097; http://lattes.cnpq.br/9195917814410737; Júlio, Armanda Aparecida; https://orcid.org/0000-0003-2182-3367; http://lattes.cnpq.br/7796202048248676; Santos, Mário Ferreira Conceição ; https://orcid.org/; http://lattes.cnpq.br/7815489824754185
Brazil is one of the largest agricultural producers in the world, however, it faces major challenges in agriculture due to the incidence of diseases in plantations, mainly fungal. Chemical control is the most used in crops, however, the disordered use of agrochemicals has caused great resistance of pathogens to synthetic fungicides currently sold. In view of this, looking for new molecules that generate less environmental impact and that are more selective for a given disease is very important. Through catalytic processes, it is possible to facilitate the synthesis of new molecules, enabling the obtaining of substances with potential fungicidal activity. In this context, the present study aims to brominate and esterify phenols of natural origin, via one pot/tandem catalytic synthesis, using CuCl2 as a catalyst and acetic anhydride as an acetylating agent, and to evaluate the antifungal effect under in vitro conditions against fungus Colletotrichum musae. The catalytic process developed, depending on the substrate, can achieve conversion and selectivity of 100%, the reactions were monitored by Gas Chromatography coupled to DIC, and the synthesized products were identified by Gas Chromatography coupled to Mass Spectrometry (GC/MS) and 1H and 13C Nuclear Magnetic Resonance e. In this system, it was possible to confirm that the catalyst promotes the reaction in the first stage, and accelerates the second stage, showing that this reaction is of the tandem type. The antifungal tests with the fungus C. musae were carried out with the synthesized products derived from eugenol and showed excellent inhibitory potential, however, the synthesis product from the first stage (IC50= 94 mg/L; IC90=474 mg/L) has better antifungal action than the product from the second stage (IC50= 314 mg/L; IC90=3100 mg/L), as it completely inhibits the fungus in lower concentrations. This research demonstrated promising results, as it was possible to develop and apply an efficient and low-cost one-pot/tandem catalytic system, and with low concentrations of the synthetic product it was possible to inhibit the mycelial development of the fungus C. musae
Caracterização e classificação da Lama de Beneficiamento de Rochas Ornamentais (LBRO) de acordo com as etapas produtivas
(Universidade Federal do Espírito Santo, 2020-08-10) Nascimento, Wenderson Abreu Rosa; Neves, Mirna Aparecida; https://orcid.org/0000-0002-3611-6414; http://lattes.cnpq.br/4696981882395783; https://orcid.org/0000-0001-6699-2469; http://lattes.cnpq.br/4108809814810145; Burak, Diego Lang; https://orcid.org/0000-0002-6758-3517; http://lattes.cnpq.br/2501042964619476; Oliveira, Michel Picanço ; https://orcid.org/0000-0001-9241-0194; http://lattes.cnpq.br/6383844066460475
The State of Espírito Santo has a large number of companies that operate in the extraction and processing of dimension stones, and is currently the largest national producer, with an emphasis on the large share of revenues from Brazilian stone slab exports. These activities generate a significant volume of waste, among which, what draws the most attention is the dimension stone processing slurry (DSPS), from the phases of block sawing and plate polishing. Thus, the variation in the physical and chemical parameters of the DSPS depends on the technology used in the processing, the quality or type of component added to the process, in addition to the quantity, which varies considerably from one company to another. Compositional variations also occur depending on the type of processed rock, the stages of water reuse, among other factors. Having the classification and characterization of the LBRO is to provide necessary subsidies for the proper management of the sludge when it is discarded, both for companies and for environmental agencies. In this study, the objective is to characterize and classify the DSPS according to the processing steps (unfolding and polishing) from collections made in companies that have conventional and diamond wire looms, and polishing machines. Therefore, the information presented allowed to classify the DSPS samples and demonstrate that the metals tend to concentrate in the liquid phase of the sludge, and, in the solid phase, the concentrations are attenuated. This demonstrate the relevance of establishing a more detailed monitoring of the raw materials and inputs, which are the components for understanding the formation and composition of the DSPS and thus properly manage the processing of rocks and minimize the appearance of contaminants in the wastes generated
Caracterização física, química e mineralógica dos sedimentos do baixo rio doce, após o rompimento da barragem de Fundão/MG
(Universidade Federal do Espírito Santo, 2023-12-15) Martins, Marx Engel; Oliveira, Fabricia Benda de; https://orcid.org/0000-0002-4456-0275; http://lattes.cnpq.br/9513837515797451; Oliveira, Carlos Henrique Rodrigues de; https://orcid.org/0000-0003-4829-8005; http://lattes.cnpq.br/1293627013882628; https://orcid.org/0009-0000-5833-5995; http://lattes.cnpq.br/9213685527968955; Vergilio, Cristiane dos Santos; https://orcid.org/0000-0003-1711-7320; http://lattes.cnpq.br/6012595909105903; Neves, Mirna Aparecida; https://orcid.org/0000-0002-3611-6414; http://lattes.cnpq.br/4696981882395783
The collapse of the Fundão dam in the municipality of Mariana, Minas Gerais, dumped a load of approximately 50 million m³ of iron mining waste into the Gualaxo do Norte River, a tributary of the Doce River, which received and continues to receive this material. Several dams along its course have held back some of the sediment in their reservoirs, but this material is still in the Rio Doce and continues to reach the Atlantic Ocean at its mouth in Regência, a district of Linhares-ES, especially during the summer, which is the period of highest flow. In this context, this work aims to characterize the waste from the dam and deposited in the river, as well as to verify changes in the geochemical aspects of river sediments in the short term, thus determining the degree of interaction between the sediments in situ and the waste. With this in mind, the grain size of the sediment and waste was determined by sieving and sedigraphy, respectively, as well as the morphology of the grains present by scanning electron microscopy (SEM). The chemical composition was determined using X-ray fluorescence (XRF) and the mineralogy of the sand, silt and clay fractions using X-ray diffractometry (XRD). SEM imaging of the sediments shows granular morphologies commonly found in fluvial sediments, such as rounded shapes and a high degree of reworking of the grains, while in the residues there are grains of laminar habit with associated microaggregates. The river sediments showed a large increase in the amount of silicon, while aluminum and iron decreased in proportion to previous studies, while the residues showed an increase in silicon content, and a decrease in iron and aluminum, which are the main components.
Caracterização físico-química de biochars provenientes de lodo de esgoto : influência de diferentes temperaturas de pirólise e atmosferas
(Universidade Federal do Espírito Santo, 2024-03-21) Pires, Keyla Bendia; Burak, Diego Lang ; https://orcid.org/0000-0002-6758-3517; http://lattes.cnpq.br/2501042964619476; Morais, Pedro Alves Bezerra ; https://orcid.org/0000-0001-5501-7350; http://lattes.cnpq.br/5220285635137407; https://orcid.org/0000-0002-5024-1510; http://lattes.cnpq.br/5123260038681397; Ferreira, Rafael de Queiroz ; https://orcid.org/; http://lattes.cnpq.br/5053247764430323; Passos, Renato Ribeiro ; https://orcid.org/0000-0001-7730-748X; http://lattes.cnpq.br/3882320619443256
This research study, driven by population growth and the ensuing environmental challenges, is dedicated to exploring sustainable solutions for the treatment of sewage sludge (SS). The principal objective was to generate biochar derived from SS at three distinct locations within the southern region of Espírito Santo, Brazil. The pyrolysis process was conducted at temperatures of 350, 550, and 750°C in the presence or absence of argon flow. Atomic absorption spectroscopy (AAS) was utilized to assess the biochar's elemental composition, employing three distinct acid extraction methodologies for the nutritional analysis. The results obtained by AAS indicated significant data for the pseudo-total availability of potassium in Cachoeiro, at 550 °C under an argon atmosphere, reaching 15 g/kg, and calcium in Itaoca at 750 °C under an oxygen atmosphere, reaching 30 g/kg. In Pacotuba, the percentage availability of calcium reached 47% at 750 °C in an oxygen atmosphere. The percentage availability of manganese in Pacotuba also exhibited a significant result, reaching 25% at three treatment temperatures in an argon atmosphere. The second phase entailed a qualitative analysis employing scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray diffraction, and Fourier transform infrared spectroscopy (FT-IR). X-ray diffraction analysis revealed the formation of turbostratic carbon structures and the formation of crystalline structures of inorganic compounds. Scanning electron microscopy (SEM) images demonstrated that the particle's interior consisted of a dark core indicative of carbon, while lighter inorganic oxides adhered to the surface. Fourier transform infrared (FT-IR) analysis revealed the presence of structures such as hydroxyl groups and C-H stretches at wavelengths between 4000 and 3500 cm-1 . The present study significantly advances our understanding of environmental stewardship in a context of sustainable agricultural practices. Biochar has been proven to be an efficacious conditioning agent for potassium and calcium, as evidenced by this study
Caracterização química de biocarvão proveniente da casca de eucalipto da espécie "Eucalyptus grandis" em diferentes condições de pirólise
(Universidade Federal do Espírito Santo, 2019-02-21) Polastreli, D'avila Leal; Profeti, Luciene Paula Roberto; Passos, Renato Ribeiro; Profeti, Demetrius
The eucalyptus plantation in Brazil occupies an area of 5.7 million hectares, with emphasis on the states of Minas Gerais, São Paulo and Mato Grosso do Sul. The companies in the planted tree sector generated in 2016, 47.8 million tons of solid waste. Of t
Caracterização química e atividade acaricida de óleos essenciais da família Lamiaceae no controle do Tetranychus urticae (Koch, 1836)
(Universidade Federal do Espírito Santo, 2023-11-27) Moura, Ludmila Vieira; Pirovani, Victor Dias; https://orcid.org/0000-0002-1143-4547; http://lattes.cnpq.br/0473851765897792; Menini, Luciana Alves Parreira; https://orcid.org/0000-0001-7041-9999; http://lattes.cnpq.br/0824035845605716; https://orcid.org/0000-0003-2042-1585; http://lattes.cnpq.br/4349291895704904; Silveira, Luiz Flávio Vianna ; https://orcid.org/0000-0002-0739-3711; http://lattes.cnpq.br/0194144452153742; Sousa, Rafael Mantovaneli; https://orcid.org/0000-0002-3754-7080; http://lattes.cnpq.br/9388241426805628
Over the years, new technologies have been developed, seeking to minimize the effects of pests in agriculture. An example of these technologies is the use of synthetic-based pesticides to control pests. However, due to the high toxicity of these products, alternative forms of pest management have been the subject of several studies. An alternative to agricultural pesticides is the use of essential oils as biopesticides. Such oils, due to their chemical composition, have biological properties such as antimicrobial, antifungal and acaricide and can be used to control pests in crops. One of the most targeted pests, as it ravages several crops, is Tetranychus urticae (Koch, 1836), popularly known as the two-spotted mite, which can multiply quickly, causing damage to plants and subsequently to fruits. Thus, the objective of this work was to use essential oils from the Lameaceae family, these being: basil oils (Ocimum basilicum L.), mint (Mentha piperita L.), oregano (Origanum vulgare L.) and thyme (Thymus vulgaris L.) as a method of managing T. urticae. In addition to evaluating the acaricidal potential of each of these essential oils, blends and major compounds of these essential oils were tested. Two-spotted mites were bred on jack bean plants under laboratory conditions. The essential oils were purchased commercially and the identification of the compounds was carried out by gas chromatography with a flame ionization detector (GC/DIC) and by gas chromatography coupled to mass spectrometry (GC/MS). The main constituents of the essential oils identified in the GC/MS were, estragole (91.8%) in basil oil, menthol (39.11%) in mint oil, carvacrol (76.80%) in oregano oil and thymol (45.76%) in thyme oil. The tests were carried out with essential oils, blends and their major compounds using the fumigation method, with basil oil (LC50= 8.02 μL.L-1 and CL90=27.30 μL.L-1), blend 8 (basilicon+oregano) (LC50= 7.21 μL.L-1 and LC90=15.66 μL.L-1) and ursol (LC50= 6.38 μL.L-1 and LC90=41.78 μL.L -1) showed greater toxicity to the two-spotted mite. Another method used was contact presenting oregano (LC50= 5.79 μL.mL-1 and CL90=11.25 μL.mL-1), blend 6 (thyme+basil) (LC50= 20.13 μL.mL -1 and LC90=46.42 μL.mL-1) and carvacrol (LC50= 19.46 μL.mL-1 and LC90= 33.82 μL.mL-1) with greater lethality against the two-spotted mite. After the end of the evaluations, the study showed that essential oils, blends and major compounds presented acaricidal potential for controlling the two-spotted mite, thus being an alternative for organic cultivation. However, studies are needed on contact action and repellency as well as its phytotoxicity to plants, studies that are currently underway.
Caracterizações químicas dos primeiros cultivadores de lúpulo (Humulus lupulus L.) produzidos no Brasil
(Universidade Federal do Espírito Santo, 2019-02-26) Silva, Camila Taiany Delfino; Pinheiro, Patrícia Fontes; Osório, Vanessa Moreira; Pereira, Alexandre Fontes; Osório, Vanessa Moreira; 1º membro da banca
The hops flower (Humulus lupulus L.), used in the production of beers, is responsible to give flavor, aroma and bitterness to the beverage and in addition, it is considered a bactericide and natural preservative. The aromas and bitterness provided by hops
Coleoptera: Scarabaeidae: Scarabaeinae e suas funções na qualidade de solos sob pastagens
(Universidade Federal do Espírito Santo, 2020-03-19) Giestas, Pedro Henrique Charpinel; Mendonca, Eduardo de Sá; https://orcid.org/0000-0003-3284-7129; http://lattes.cnpq.br/4735276653354808; https://orcid.org/0000-0001-9199-065X; http://lattes.cnpq.br/8099384165242070; Burak, Diego Lang; https://orcid.org/0000-0002-6758-3517; http://lattes.cnpq.br/2501042964619476; Santos Junior, Hugo José Gonçalves dos ; https://orcid.org/0000-0002-6780-6610; http://lattes.cnpq.br/8499663924650322
The dominance of degraded pastures in Brazil and the State of Espírito Santo negatively impacts the diversity of organisms and carbon stocks in the soil. Our work aimed at understanding how different levels of degraded pastures and forest fragments affect the diversity and ecological functions performed by dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) and what is the relationship of these services on soil quality and attributes related to the organic matter in the Caparaó Capixaba region, south of Espírito Santo and in the laboratory. For the field experiment, 21 sample areas were selected, with seven forest fragments (FFL) and 14 pastures (seven with high level of degradation (PAD) and seven with low level of degradation (PBD)) in the municipalities of Alegre and Guaçuí – ES. In these areas, soil samples were collected at depths of 0 to 10 and 10 to 20 cm, CO2 emission samples, resistance to soil penetration, soil temperature and humidity, and ecosystem functions, richness, abundance and composition of dung beetles were also quantified. In the laboratory experiment, 20 experimental PVC structures were filled with soil and bovine feces and divided in two treatments, one containing an individual of Dichotomius bos (n=10) and another treatment without a beetle (n=10). Among the studied environments, PBD showed higher rates of dung burial (246.96 g ± 24.65) and soil excavation (339.08 g ± 58.81). DBP showed lower means for both functions. Pastures reduced the mean richness (1.90 ± 0.29) and abundance (16.52 ± 7.28) of scarabaeinae compared to FFL, being lower in PADs. We did not find any correlation between the richness and abundance of the beetles with the attributes of soil organic matter studied in the field experiment. In the field, PBD had a higher CO2 emission (2.94 cmol-1 ± 0.29) among the areas. In the laboratory experiment, the treatment with the presence of the beetle increased the content of the soil organic matter attributes. The treatment without a beetle showed a higher CO2 emission (9.44 cmol-1 ± 0.91) in the first hours after the feces entered the system. We conclude that PAD favor the increase in the surface runoff of water due to the low vegetation cover and higher values for resistance to penetration, resulting in erosive processes, inefficiency in carbon mobilization and modify the functioning of the ecosystem, negatively influencing the diversity and ecological functions of dung beetles
Defensivos alternativos para controle da antracnose e pinta-preta em mamão
(Universidade Federal do Espírito Santo, 2019-02-26) Rodrigues, Lais Oliveira; Zucoloto, Moises; Tomaz, Marcelo Antônio; Belan, Leônidas Leoni
The papaya (Carica papaya L.) is a tropical crop, economically important for Brazil and susceptible to numerous diseases, such as anthracnose (Colletotrichum gloeosporioides) and black-spot (Asperisporium caricae). Due to the possibility of phytopathogens
DESENVOLVIMENTO DE METODOLOGIA PARA DETECÇÃO DE FORMALDEÍDO EM AMOSTRAS DE LEITE POR CG-EM.
(Universidade Federal do Espírito Santo, 2021-03-12) Vaz, Everton Barbosa; Menini, Luciano; https://orcid.org/0000000336565428; http://lattes.cnpq.br/2646344913961349; https://orcid.org/0000-0002-7735-6350; http://lattes.cnpq.br/0056085814873216; Donatele, Dirlei Molinari; https://orcid.org/0000-0002-5697-749X; http://lattes.cnpq.br/5785667334058207; Bernardes, Patricia Campos; https://orcid.org/0000000200123890; http://lattes.cnpq.br/0443413246742848
Milk is one of the most consumed foods in the world due to its high nutritional value. Because it has a pH close to neutrality, milk is a product conducive to the appearance of undesirable microorganisms. The milk industry(the dairy industry) has the obligation to supply a good quality product and the heat treatments have the function of eliminating the contamination present there. Industry must also supply a product that is free from any adulteration. The use of preservatives is the most common adulteration as/since formaldehyde for example, is used to eliminate microorganisms. Formaldehyde is a very toxic and carcinogenic compound and causes irreparable damage to the health of those who consume it. In the present study, a gas chromatography method for the determination of formaldehyde in milk samples was developed and validated. The methodology used was developed and applied to milk samples from twelve different brands with two lots of each make. The developed methodology allowed a quantitative analysis of formaldehyde in milk samples. The obtained results in this study lie within what was suggested by the European Food Safety Authority (EFSA), which is 0.1ppm - 0.8 ppm. Gas chromatography coupled to the mass spectrometer allowed for better analysis of the samples, providing better selectivity, precision and greater reliability of the results.
Desenvolvimento e efeito de emulsões contendo compostos bioativos sobre Fusarium oxysporum f. sp. lycopersici e qualidade fisiológica de sementes de tomate
(Universidade Federal do Espírito Santo, 2024-01-23) Peccini, Luan Rezende; Costa, Adilson Vidal ; https://orcid.org/0000-0002-7968-8586; http://lattes.cnpq.br/1638000107452454; Pires, Raquel Maria de Oliveira ; https://orcid.org/0000-0003-1369-4323; http://lattes.cnpq.br/8684079739368288; Queiroz, Vagner Tebaldi ; https://orcid.org/0000-0002-8170-125X; http://lattes.cnpq.br/9963384168622230; https://orcid.org/0009-0003-3852-3085; http://lattes.cnpq.br/7618612386769420; Soares, Lucas de Souza ; https://orcid.org/0000-0003-2997-5349; http://lattes.cnpq.br/2486212144163484; Flores, Rafaela Venancio ; https://orcid.org/0000-0002-5498-336X; http://lattes.cnpq.br/5961658843017289
Tomato is the solanaceous crop frequently affected by various pathogens, including the fungus Fusarium oxysporum f. sp. lycopersici (Fol), which causes Fusarium wilt and reduces productivity. In this study, different formulations containing thymol (Thy) or carvacrol (Car) were developed and their effects on Fol and the physiological quality of tomato seeds were evaluated. Thy emulsions (EsT) were developed considering surfactant concentration, vortex homogenization time (HVtx) and high-intensity ultrasound time (HHUs). EsT9%S1 emulsion, comprising 9.0% surfactant, 2.5 minutes of HVtx and 3.0 min of HHUs, kept kinetic stability over a 28 day storage period. EsT9%S1 showed antifungal activity against Fol at inhibitory concentrations of IC50 = 0.052 mg mL -1 and IC90 = 0.268 mg mL-1 . Seeds treated with EsT9%S1 maintained electrical conductivity (EC) and pH in the range of 240.9 to 597.7 μS cm-1 g -1 and 6.8 to 7.6, respectively over 24h. Additionally, no signs of phytotoxicity were observed in the tomato seeds. Coatings using cassava starch (CS) and glycerol (Glyc), incorporating different concentrations of carvacrol nanoemulsion (CNE) and/or red cabbage extract (RCE) were developed and characterized. Analysis of the FTIR and XRD spectra showed interactions among CS, Glyc, CNE, and/or RCE, indicated by shifts/emergence of new bands, and the appearance of amorphous peaks. The incorporation of CNE, and/or RCE made the film's surface more rough, increased thermal stability and EC, decreased pH, and modified solubility and swelling properties. Films with the addition of CNE and/or RCE exhibited antioxidant activity, an important property for protecting seeds against oxidative stress. Physiological analyses revealed the absence of phytotoxicity in the coatings applied to the tomato seeds. The results highlight the potential of EsT9%S1 and the films containing CS, Glyc, CNE, and/or RCE for evaluation as tomato seed coatings

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