Produção Nacional
Revisado por pares
Natália Cristina Corrêa de Oliveira, Paulo Sérgio Nascimento Lopes, Leonardo Monteiro Ribeiro, M. O. Mercandante-Simões, Leonardo A. Oliveira, Flaviano Oliveira Silvério,
Tópico(s): Fern and Epiphyte Biology
2013 - Springer Science+Business Media | Trees
Produção Nacional
Revisado por pares
Rodrigo Aparecido Domingues de Oliveira, Silma da Conceição Neves, Leonardo Monteiro Ribeiro, Paulo Sérgio Nascimento Lopes, Flaviano Oliveira Silvério,
Attalea vitrivir is a neotropical palm with exceptional potential for biofuel production. We evaluated the effects of different storage methods on seed and oil quality and the viability of using cryopreservation for conserving its genetic resources. Fruits were stored for 365 days in the open air (OA); under shade (SH); in the shade in polyethylene bags (PO); and in a cold chamber at 10 °C (CC); seeds were stored for 180 days in SH, PO and CC. We evaluated embryo viability as well as the acid value and ...
Tópico(s): Growth and nutrition in plants
2016 - Elsevier BV | Industrial Crops and Products
Produção Nacional
Revisado por pares
Tayane C. R. Mesquita, Rizia Rodrigues Santos, Ane Patrícia Cacique, Ludimara J. De SÁ, Flaviano Oliveira Silvério, Gevany Paulino de Pinho,
Organochlorine pesticides present in sewage sludge can contaminate soil and water when they are used as either fertilizer or agricultural soil conditioner. In this study, the technique solid–liquid extraction with low temperature purification was optimized and validated for determination of ten organochlorine pesticides in sewage sludge and soil samples. Liquid–liquid extraction with low temperature purification was also validated for the same compounds in water. Analyses were performed by gas chromatography- ...
Tópico(s): Toxic Organic Pollutants Impact
2017 - Taylor & Francis | Journal of Environmental Science and Health Part B
Produção Nacional
Revisado por pares
Flaviano Oliveira Silvério, Elson S. Alvarenga, Shaiene Costa Moreno, Marcelo Coutinho Picanço,
Abstract BACKGROUND: Pyrethroids are among the most potent pesticides known, with great potential for structural variation with retention or enhancement of potency. The simple methyl ester is easier to prepare (at least one step shorter) than the more complex pyrethroids modified on the alcohol moiety. The objective was to synthesise methyl esters of pyrethroid acids containing an aromatic ring on the acid moiety and evaluate their biological activity against Ascia monuste orseis Latr., Tuta absoluta ...
Tópico(s): Pesticide and Herbicide Environmental Studies
2009 - Wiley | Pest Management Science
Produção Nacional
Revisado por pares
Gevany Paulino de Pinho, Antônio Augusto Neves, José Humberto de Queiróz, Flaviano Oliveira Silvério,
MATRIX EFFECT IN PESTICIDE QUANTIFICATION BY GAS CHROMATOGRAPHY.The lack of accuracy of a chromatographic method can be associated with the matrix effect.This effect is observed in pesticide quantification by gas chromatography when the chromatographic signals of standards prepared in solvents are compared with those of the analyte in extracts of complex matrices.In the competition between the matrix components and the pesticides for the active sites of the liner, a larger amount of pesticides is ...
Tópico(s): Pesticide and Herbicide Environmental Studies
2009 - Brazilian Chemical Society | Química Nova
Produção Nacional
Revisado por pares
Gevany Paulino de Pinho, Antônio Augusto Neves, José Humberto de Queiróz, Flaviano Oliveira Silvério,
In this work, a simple and low cost method, based on solid–liquid extraction with low temperature purification (SLE–LTP), was optimized and validated for the determination of chlorpyrifos, λ-cyhalothrin, cypermethrin and deltamethrin in tomato samples. The analyses were performed by the GC–ECD and confirmed by the GC–MS. The method requires 4 g of tomato and an extraction mixture (8.0 mL acetonitrile, 0.5 mL water and 1.5 mL ethyl acetate), which was established by mixture experimental design. After ...
Tópico(s): Analytical Chemistry and Chromatography
2009 - Elsevier BV | Food Chemistry
Produção Nacional
Revisado por pares
Cláudio F. Lima, Luiz C. A. Barbosa, Cristiana Resende Marcelo, Flaviano Oliveira Silvério, Jorge Luiz Colodette,
Pyrolysis-gas chromatography/mass spectrometry (Py-GC-MS) was applied to measure the lignin syringyl/guaiacyl (S/G) ratio in E. dunni, E. grandis, E. nitens, E. urograndis, and E. urophylla woods. A total of 41 compounds were identified, of which 11 were derived from carbohydrates and 30 from lignins. The S/G ratio was calculated on the basis of the areas of peaks recorded in the pyrograms and compared with the results obtained by alkaline nitrobenzene oxidation. The values of S/G found by pyrolysis ...
Tópico(s): Enzyme-mediated dye degradation
2008 - North Carolina State University | BioResources
Produção Nacional
Revisado por pares
Flaviano Oliveira Silvério, Luiz C. A. Barbosa, Dorila Piló‐Veloso,
PYROLYSIS AS AN ANALYTICAL TECHNIQUE.In this paper historical aspects of analytical pyrolysis, the equipment used, the fundamentals and the mechanisms of pyrolysis of different polymeric materials are discussed.The latest work on analytical pyrolysis applied to various types of synthetic and natural samples is reviewed.Current applications of this technique that are discussed include identification of microorganisms, analysis of trace compounds by forensic laboratories, investigation of food and ...
Tópico(s): Cultural Heritage Materials Analysis
2008 - Brazilian Chemical Society | Química Nova
Produção Nacional
Revisado por pares
Gevany Paulino de Pinho, Antônio Augusto Neves, José Humberto de Queiróz, Flaviano Oliveira Silvério,
Tópico(s): Bee Products Chemical Analysis
2010 - Elsevier BV | Food Control
Produção Nacional
Revisado por pares
Cleiton Antônio Nunes, Cláudio F. Lima, Luiz C. A. Barbosa, Jorge Luiz Colodette, Ana F. Gouveia, Flaviano Oliveira Silvério,
The syringyl/guaiacyl ratio was determined for six different Eucalyptus spp. wood clones cultivated in four regions in Brazil. The determinants were made by pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) and the results were compared with those obtained by alkaline nitrobenzene oxidation method. The S/G ratios were obtained considering all the identified lignin derivatives in the pyrograms and also using two groups of markers. The first group of markers consisted of guaiacol, 4-methylguaiacol, ...
Tópico(s): Biochemical and biochemical processes
2010 - Elsevier BV | Bioresource Technology
Produção Nacional
Revisado por pares
Flaviano Oliveira Silvério, Luiz C. A. Barbosa, Célia R. A. Maltha, Paulo Henrique Fidêncio, Mariluze Peixoto Cruz, Dorila Piló Veloso, Augusto Milanez,
Lipophilic wood extractives commonly referred to as pitch, cause significant problems for the pulp and paper industries. The reduction of these extractives is an important aspect that concerns industries around the world. In the present work the change in the amount and chemical composition of lipophilic extractives from Eucalyptus spp. stored for 20, 40, 60, 100, 140 and 180 days after harvesting was investigated. The results showed a decrease in extractives content with storage time, with the ...
Tópico(s): Forest ecology and management
2007 - Elsevier BV | Bioresource Technology
Produção Nacional
Revisado por pares
Flaviano Oliveira Silvério, Luiz C. A. Barbosa, Célia R. A. Maltha, Armando J. D. Silvestre, Dorila Piló‐Veloso, José Lívio Gomide,
The chemical compositions of the lipophilic extractives from four clones of Eucalyptus urograndis cultivated in Brazil were studied by gas chromatography-mass spectrometry (GC-MS) before and after alkaline hydrolysis. The four E. urograndis clones showed similar amounts of dichloromethane soluble (lipophilic) extractives (0.38-0.55% w/w). The major groups of compounds identified in the lipophilic fraction of extractives consisted mainly of fatty acids (mainly palmitic linoleic and oleic acids and small ...
Tópico(s): Plant biochemistry and biosynthesis
2007 - North Carolina State University | BioResources
Produção Nacional
Revisado por pares
Flaviano Oliveira Silvério, Luiz C. A. Barbosa, Armando J. D. Silvestre, Dorila Piló‐Veloso, José Lívio Gomide,
Abstract The chemical compositions of lipophilic fractions from Eucalyptus urograndis and Eucalyptus urophylla cultivated in Brazil and Eucalyptus camaldulensis from Mexico were determined by gas chromatography-mass spectrometry (GC-MS) before and after alkaline hydrolysis followed by derivatization. In all fractions, fatty acids (including small amounts of α-and ω-hydroxy fatty acids) and sterols were the most abundant components followed by smaller amounts of long-chain aliphatic alcohols, phenolic ...
Tópico(s): Plant-Derived Bioactive Compounds
2007 - Springer Science+Business Media | Journal of Wood Science
Produção Nacional
Revisado por pares
Francis Júlio Fagundes Lopes, Flaviano Oliveira Silvério, David Carlos Ferreira Baffa, Marcelo Loureiro, Márcio Henrique Pereira Barbosa,
Abstract In this work, analytical pyrolysis (Py-GC-MS) was employed to identify lignin markers derived from H, S, and G phenylpropanoid units in sugarcane bagasse. Temperatures of 450 and 500°C allowed the detection of key products that were informative on the bagasse lignin composition. The method was validated by comparing the S/G ratio as determined by the nitrobenzene oxidation (NBO) standard method for five sugarcane varieties. The S/G ratio as determined by Py-GC-MS, taking into consideration ...
Tópico(s): Plant Gene Expression Analysis
2011 - Taylor & Francis | Journal of Wood Chemistry and Technology
Produção Nacional
Revisado por pares
Flaviano Oliveira Silvério, Luiz C. A. Barbosa, José Lívio Gomide, Fernando Pinheiro Reis, Dorila Piló‐Veloso,
Neste trabalho foi avaliado o teor de extrativos em madeiras de eucalipto, por meio de extrações com acetona, mistura de tolueno:etanol (2:1), clorofórmio e diclorometano. As maiores porcentagens de extrativos totais foram obtidas ao utilizar acetona como solvente. Os extratos obtidos em acetona e tolueno:etanol foram ressuspendidos em diclorometano, para avaliação do teor de extrativos lipofílicos. As porcentagens desses extrativos foram semelhantes às obtidas com diclorometano ou clorofórmio, em ...
Tópico(s): Wood Treatment and Properties
2006 - Sociedade de Investigações Florestais | Revista Árvore
Produção Nacional
Revisado por pares
Flaviano Oliveira Silvério, Joyce Grazielle Siqueira Silva, Maria Clara Santana Aguiar, Ane Patrícia Cacique, Gevany Paulino de Pinho,
HIGH PERFORMANCE LIQUID CHROMATOGRAPHY.This study optimized and validated the liquid-liquid extraction technique with partition at low temperature (LLE-PLT) for identification and quantification of four pesticides (chlorpyrifos, λ-cyhalothrin, permethrin, bifenthrin) in water samples.Analyses were performed by HPLC-UV.The technique was efficient for pesticide recovery with extraction exceeding 86%.Chromatographic response was linear for the four compounds in the 10-45 µg L -1 range, with correlation ...
Tópico(s): Analytical chemistry methods development
2012 - Brazilian Chemical Society | Química Nova
Produção Nacional
Revisado por pares
Tereza Cristina Pimenta Gonçalves Catrinck, Amanda Latércia Tranches Dias, Maria Clara Santana Aguiar, Flaviano Oliveira Silvério, Paulo Henrique Fidêncio, Gevany Paulino de Pinho,
Este trabalho apresenta a confirmação e otimização do método para derivatização de glifosato e ácido aminometilfosfônico (AMPA) utilizando cloroformiato de 9-fluorenilmetila (FMOC-Cl) avaliando-se os parâmetros: concentração de tampão borato e de FMOC-Cl, tempo de homogeneização e de reação, comprimento de onda e solvente de lavagem.A reação foi promovida com sucesso e o método é simples e de fácil execução pois utiliza cinco minutos de homogeneização e permite análises no ultravioleta imediatamente ...
Tópico(s): DNA and Nucleic Acid Chemistry
2014 - Brazilian Chemical Society | Journal of the Brazilian Chemical Society
Produção Nacional
Revisado por pares
Maria Clara Santana Aguiar, Flaviano Oliveira Silvério, Gevany Paulino de Pinho, Paulo Sérgio Nascimento Lopes, Paulo Henrique Fidêncio, Sílvia Juliane Ventura,
The chemical composition of volatile substances from fruits of jelly palm (Butia capitata) was investigated at four stages of maturity and two storage conditions. These stages were characterized through the profile obtained by extraction of volatiles through headspace chromatography and analyzed by GC-MS. In mature fruits 25 compounds were extracted, but primarily consisted of ethyl hexanoate (65.9%), ethyl butanoate (14.5%) and methyl hexanoate (9.64%). The composition at different stages of maturity ...
Tópico(s): Botanical Research and Applications
2014 - Elsevier BV | Food Research International
Produção Nacional
Revisado por pares
Katalin Carrara Geöcze, Luiz C. A. Barbosa, Paulo Henrique Fidêncio, Flaviano Oliveira Silvério, Cláudio F. Lima, Maria C. A. Barbosa, Fyaz M.D. Ismail,
The composition of the essential oils of pequi fruits gathered from the Brazilian Cerrado ecosystem in the states of Maranhão (MA), Minas Gerais (MG) and Tocantins (TO) was investigated. The oils were obtained by steam distillation, and each component was speciated using GC-MS. The oil content varied from 0.13% to 1.15%. Interestingly, the major substance found within samples from two of the states was ethyl hexanoate (MA, MG), whereas isopropyl hexanoate and isopentyl-2-methylbutanoate were specific ...
Tópico(s): Plant and animal studies
2013 - Elsevier BV | Food Research International
Produção Nacional
Revisado por pares
Ane Patrícia Cacique, Érica Soares Barbosa, Gevany Paulino de Pinho, Flaviano Oliveira Silvério,
ABSTRACT Catharanthus roseus(L.) G. Don is a medicinal plant known for its important constituent aromatic compounds. In the literature, no detailed studies elucidating the methods of extraction of phenolic compounds for this species are available. Therefore, the present study was aimed at evaluating the maceration parameters for determining the total phenols content in C. roseus. The parameters of plant mass, extraction phase composition, homogenization type, extraction time, and temperature were ...
Tópico(s): Phytochemistry and Biological Activities
2020 - UNIVERSIDADE FEDERAL DE LAVRAS | Ciência e Agrotecnologia
Produção Nacional
Revisado por pares
Gevany Paulino de Pinho, Flaviano Oliveira Silvério, Antônio Augusto Neves, José Humberto de Queiróz, Maria Antônia V. M. Starling,
CHROMATOGRAPHIC RESPONSE.Multiresidue methods for pesticides monitoring by GC are commonly employed, however, it is well known that the presence of compounds of the matrix introduces errors during the quantification.The main consequence of matrix effect is an increasing or decreasing analyte signal after the GC saturation with extracts of matrix.In this paper, the influence of constituents of nine matrices on the quantification of the four pesticides by GC-ECD was studied.Variation of signal was ...
Tópico(s): Pesticide and Herbicide Environmental Studies
2010 - Brazilian Chemical Society | Química Nova
Produção Nacional
Revisado por pares
Gevany Paulino de Pinho, Juliana R. M. Matoso, Flaviano Oliveira Silvério, Welha C. Mota, Paulo Sérgio Nascimento Lopes, Leonardo Monteiro Ribeiro,
O objetivo deste trabalho foi desenvolver um novo método espectrofotométrico, de elevada sensibilidade, eficiente e de fácil execução para determinar a atividade enzimática da endo-βmananase em sementes.O método espectrofotométrico foi otimizado e aplicado em amostras de sementes de Butia capitata para determinar a localização da atividade enzimática em diferentes partes das sementes.O método consiste em extrair a enzima da semente e utilizá-la para hidrolisar o galactomanano Locust Bean Gum.Os ...
Tópico(s): Phytase and its Applications
2014 - Brazilian Chemical Society | Journal of the Brazilian Chemical Society
Produção Nacional
Revisado por pares
João Paulo Fernandes Tiago, Lázaro Chaves Sicupira, Rodrigo Eduardo Barros, Gevany Paulino de Pinho, Flaviano Oliveira Silvério,
Glyphosate is the main herbicide currently used in the world due to wide applicability and efficiency in controlling weeds in many crops. However, its overuse may lead to undesirable impacts on the environment and to human health in the long run. This present study aimed to optimize and validate solid phase extraction (SPE) using an anionic resin for the simultaneous and direct determination of glyphosate and aminomethylphosphonic acid (AMPA) in water samples using high-performance liquid chromatography ...
Tópico(s): Pesticide Residue Analysis and Safety
2020 - Taylor & Francis | Journal of Environmental Science and Health Part B
Produção Nacional
Revisado por pares
Lucas Victor Pereira de Freitas, Lorena Maria Guimarães Alves, Lázaro Chaves Sicupira, Gevany Paulino de Pinho, Flaviano Oliveira Silvério,
This paper describes a new method for the determination of DDT in honey samples by liquid–liquid extraction with low-temperature purification (LLE-LTP) combined with HPLC-DAD.
Tópico(s): Bee Products Chemical Analysis
2021 - Royal Society of Chemistry | Analytical Methods
Produção Nacional
Revisado por pares
Mariana R. Maia, Ana Luíza P. Arcanjo, Gevany Paulino de Pinho, Flaviano Oliveira Silvério,
Sewage sludge is the residue produced by the wastewater treatment plants, which can be used as soil conditioner in agriculture.However, the current legislation recommends monitoring chemical contaminants such as polychlorinated biphenyls (PCBs).In this study, solid-liquid extraction with low temperature purification (SLE-LTP) was optimized and validated for monitoring six PCBs.The analyses were performed by gas chromatography and mass spectrometry.Sulfur interference was removed by 1.5 g of copper ...
Tópico(s): Toxic Organic Pollutants Impact
2016 - Brazilian Chemical Society | Journal of the Brazilian Chemical Society
Produção Nacional
Revisado por pares
Elson S. Alvarenga, Vânia M. T. Carneiro, Flaviano Oliveira Silvério, William Argolo Saliba,
A HIGH YIELD SYNTHESIS OF 1,2:5,6-DI-O-ISOPROPYLIDENE-D-MANNITOL: A great improvement in the synthesis of 1,2:5,6-di-O-isopropylidene-D-mannitol (2) using D-mannitol (1) as starting material, is described.The acetalation of (Δ) was performed in acetone in the presence of zinc chloride as catalyst to give (2) in 87% yield.Some studies on the acetal stability were carried out to explain the high yields.High field NMR spectra were obtained and assignment of all signals was accomplished with the aid of ...
Tópico(s): Various Chemistry Research Topics
2006 - Sociedad Chilena de Química | Journal of the Chilean Chemical Society
Produção Nacional
Revisado por pares
Marta B. Ramalho, Alisson Farley Soares Durães, Flaviano Oliveira Silvério, Gevany Paulino de Pinho,
Cresols are chemical contaminants derivative from phenol which can be found in sewage sludge. However, little attention has been given to monitoring these compounds in environmental matrices in the literature. Thus, the objective of this study was to develop a simple method based on solid-liquid extraction with low temperature purification for determining three cresol isomers in sludge. The quantification of these compounds was performed by gas chromatography coupled to mass spectrometry with a ...
Tópico(s): Environmental Toxicology and Ecotoxicology
2019 - Taylor & Francis | Journal of Environmental Science and Health Part B
Produção Nacional
Revisado por pares
Cláudio F. Lima, Luiz C. A. Barbosa, Marcela N.N. Silva, Jorge Luiz Colodette, Flaviano Oliveira Silvério,
Pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS) was used for evaluating the syringyl/guaiacyl (S/G) ratios of residual lignins in oxygen pre-bleached kraft pulps from 24 Eucalyptus wood clones. The optimization of the method showed that the best conditions were achieved when pyrolysis is carried out at 550 °C, using a 60 m length SPB-1701 capillary column and the mass spectrometer operating in SIM mode. Pulp pyrograms were analyzed and the compounds produced by pyrolysis ...
Tópico(s): Biochemical and biochemical processes
2015 - Elsevier BV | Journal of Analytical and Applied Pyrolysis
Produção Nacional
Revisado por pares
Najara Glenda Frota Pereira, Flaviano Oliveira Silvério, Gevany Paulino de Pinho,
Sewage sludge is a by-product obtained from sewage treatment plants (STP) that can be used to improve physical and chemical properties of the soil. However, xenobiotic compounds such as phthalates can be found in this material. Thus, the objective of this study was to optimise and validate the solid-liquid extraction with low-temperature purification (SLE-LTP) for the determination of five phthalates in sludge samples. Analyses were performed by gas chromatography coupled to the mass spectrometry ( ...
Tópico(s): Pharmaceutical and Antibiotic Environmental Impacts
2019 - Taylor & Francis | International Journal of Environmental & Analytical Chemistry
Shaiene Costa Moreno, Marcelo C. Picanço, Flaviano Oliveira Silvério, Elson S. Alvarenga, Geraldo Andrade Carvalho,
Pyrethroids are among the most potent and effective pesticides identified with great potential for structural variation with retention or enhancement of potency. Our objective was to evaluate the biological activity of novel methyl esters of pyrethroid acids containing an aromatic ring on the acid moiety against the social insects Protonectarina sylveirae (Saussure) (Hymenoptera: Vespidae), Solenopsis saevissima (Smith) (Hymenoptera: Formicidae) and Tetragonisca angustula (Latr.) (Hymenoptera: Apidae: ...
Tópico(s): Pesticide Exposure and Toxicity
2009 - UNIVERSIDADE ESTADUAL DE FEIRA DE SANTANA | Sociobiology