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Gisele Gimenes - One of the best experts on this subject based on the ideXlab platform.
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Biodeterioração de madeira de teca (Tectona Grandis L.) submetida ao ataque de fungos lignocelulolíticos
2019Co-Authors: Gisele GimenesAbstract:Orientador: Prof. Dr. Márcio Pereira da RochaCoorientadores: Prof. Dr. Celso Garcia Auer, Profa. Dra. Mayara Elita Braz CarneiroDissertação (mestrado) - Universidade Federal do Paraná, Setor de ..., Programa de Pós-Graduação em... Defesa : Curitiba,Inclui referências: p. 87-99Área de concentração: Tecnologia e Utilização de Produtos FlorestaisResumo: Diante da necessidade da utilização de recursos renováveis nas áreas de tecnologia e de materiais, a madeira se destaca por ser um produto versátil, reutilizável e biodegradável. O estudo da biodeterioração da madeira possui grande importância para o desenvolvimento de produtos preservantes menos nocivos ao meio ambiente e à saúde humana, assim como também para aplicações em processos biotecnológicos. A madeira de teca (Tectona Grandis L.) apresenta elevada resistência mecânica e estabilidade dimensional, porém, possui como principal característica sua elevada durabilidade natural por possuir em seus extrativos compostos antimicrobianos e repelentes. Este estudo objetivou caracterizar a biodeterioração da madeira de teca através de ensaios de resistência natural acelerada em laboratório, submetendo madeira de cerne e de alburno ao ataque de três fungos apodrecedores: Trametes versicolor, Gloeophyllum trabeum e Postia placenta. Análises químicas quantitativas (solubilidade em NaOH a 1%, teor de extrativos totais, lignina total, teor de holocelulose) e caracterização microscópica foram realizadas mensalmente. O ensaio de resistência natural acelerada em laboratório verificou que a madeira de cerne se apresentou altamente resistente a T. versicolor e P. placenta e resistente a G. trabeum. Com relação à madeira de alburno, esta mostrou ser resistente a P. placenta e moderadamente resistente a T. versicolor e G. trabeum. A química da biodeterioração da madeira ao longo do tempo revelou que todos os fungos testados apresentaram atividade hidrolítica. O fungo P. placenta revelou ser o fungo que mais degradou a holocelulose ao final do ensaio. O fungo T. versicolor apresentou comportamento seletivo. A microscopia eletrônica de varredura demonstrou invasão de hifas no interior dos vasos logo ao final do primeiro mês para todos os fungos. A madeira atacada por T. versicolor e P. placenta apresentou considerável deterioração da madeira de alburno a partir da segunda coleta, com total destruição de sua estrutura ao final do ensaio. G. trabeum promoveu sinais de deterioração apenas ao final da terceira coleta, porém, houve elevada deterioração ao final do ensaio. Palavras-chave: Tectona Grandis. Biodeterioração. Fungos basidiomicetos.Abstract: Faced to the need to use renewable resources in technology and material's areas, wood stands out as a versatile, renewable and biodegradable product. The biodegradation study of wood is of great importance for the development of preservatives less harmful to the environment and human health, as well as for applications in biotechnological processes. Teak wood (Tectona Grandis L.) is a noble wood, with high mechanical resistance and dimensional stability, but its main characteristic is its high natural durability, because it has antimicrobial compounds and repellents in their extractives. This study aimed to characterize the teak wood biodegradation by accelerated laboratory tests of natural decay resistance, subjecting wood of heartwood and sapwood to the attack of three rotting fungi: Trametes versicolor, Gloeophyllum trabeum and Postia placenta. Quantitative chemical analyzes (solubility in 1% NaOH, total extractives content, total lignin content, holocellulose content) and microscopic characterization was verified every month. The accelerated laboratory tests of natural decay resistance demonstrated that the heartwood was highly resistant to T. versicolor and P. placenta and resistant to G. trabeum. Regarding sapwood, it was resistant to P. placenta and moderately resistant to T. versicolor and G. trabeum. All fungi tested showed hydrolytic activity. The fungus T. versicolor presented selective behavior. The fungus P. placenta was the fungus that most depleted holocellulose at the end of the test. Scanning electron microscopy demonstrated invasion of hyphae within the vessels at the end of the first month for all fungi. The sapwood wood attacked by T. versicolor and P. placenta presented considerable degradation from the second month, with total destruction of the wood structure at the end of the test. G. trabeum showed signs of degradation only at the end of the third month; however, there was high degradation at the end of the test. Keywords: Tectona Grandis. Biodeterioration. Basidiomycetes fung
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Biodeterioração de madeira de teca (Tectona Grandis L.) submetida ao ataque de fungos lignocelulolíticos
2019Co-Authors: Gisele GimenesAbstract:Orientador: Prof. Dr. Márcio Pereira da RochaCoorientadores: Prof. Dr. Celso Garcia Auer, Profa. Dra. Mayara Elita Braz CarneiroDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal. Defesa: Curitiba, 24/05/2019Inclui referências: p. 87-99Área de concentração: Tecnologia e Utilização de Produtos FlorestaisResumo: Diante da necessidade da utilização de recursos renováveis nas áreas de tecnologia e de materiais, a madeira se destaca por ser um produto versátil, reutilizável e biodegradável. O estudo da biodeterioração da madeira possui grande importância para o desenvolvimento de produtos preservantes menos nocivos ao meio ambiente e à saúde humana, assim como também para aplicações em processos biotecnológicos. A madeira de teca (Tectona Grandis L.) apresenta elevada resistência mecânica e estabilidade dimensional, porém, possui como principal característica sua elevada durabilidade natural por possuir em seus extrativos compostos antimicrobianos e repelentes. Este estudo objetivou caracterizar a biodeterioração da madeira de teca através de ensaios de resistência natural acelerada em laboratório, submetendo madeira de cerne e de alburno ao ataque de três fungos apodrecedores: Trametes versicolor, Gloeophyllum trabeum e Postia placenta. Análises químicas quantitativas (solubilidade em NaOH a 1%, teor de extrativos totais, lignina total, teor de holocelulose) e caracterização microscópica foram realizadas mensalmente. O ensaio de resistência natural acelerada em laboratório verificou que a madeira de cerne se apresentou altamente resistente a T. versicolor e P. placenta e resistente a G. trabeum. Com relação à madeira de alburno, esta mostrou ser resistente a P. placenta e moderadamente resistente a T. versicolor e G. trabeum. A química da biodeterioração da madeira ao longo do tempo revelou que todos os fungos testados apresentaram atividade hidrolítica. O fungo P. placenta revelou ser o fungo que mais degradou a holocelulose ao final do ensaio. O fungo T. versicolor apresentou comportamento seletivo. A microscopia eletrônica de varredura demonstrou invasão de hifas no interior dos vasos logo ao final do primeiro mês para todos os fungos. A madeira atacada por T. versicolor e P. placenta apresentou considerável deterioração da madeira de alburno a partir da segunda coleta, com total destruição de sua estrutura ao final do ensaio. G. trabeum promoveu sinais de deterioração apenas ao final da terceira coleta, porém, houve elevada deterioração ao final do ensaio. Palavras-chave: Tectona Grandis. Biodeterioração. Fungos basidiomicetos.Abstract: Faced to the need to use renewable resources in technology and material's areas, wood stands out as a versatile, renewable and biodegradable product. The biodegradation study of wood is of great importance for the development of preservatives less harmful to the environment and human health, as well as for applications in biotechnological processes. Teak wood (Tectona Grandis L.) is a noble wood, with high mechanical resistance and dimensional stability, but its main characteristic is its high natural durability, because it has antimicrobial compounds and repellents in their extractives. This study aimed to characterize the teak wood biodegradation by accelerated laboratory tests of natural decay resistance, subjecting wood of heartwood and sapwood to the attack of three rotting fungi: Trametes versicolor, Gloeophyllum trabeum and Postia placenta. Quantitative chemical analyzes (solubility in 1% NaOH, total extractives content, total lignin content, holocellulose content) and microscopic characterization was verified every month. The accelerated laboratory tests of natural decay resistance demonstrated that the heartwood was highly resistant to T. versicolor and P. placenta and resistant to G. trabeum. Regarding sapwood, it was resistant to P. placenta and moderately resistant to T. versicolor and G. trabeum. All fungi tested showed hydrolytic activity. The fungus T. versicolor presented selective behavior. The fungus P. placenta was the fungus that most depleted holocellulose at the end of the test. Scanning electron microscopy demonstrated invasion of hyphae within the vessels at the end of the first month for all fungi. The sapwood wood attacked by T. versicolor and P. placenta presented considerable degradation from the second month, with total destruction of the wood structure at the end of the test. G. trabeum showed signs of degradation only at the end of the third month; however, there was high degradation at the end of the test. Keywords: Tectona Grandis. Biodeterioration. Basidiomycetes fung
Fabián Hidalgo, Karen Nathaly - One of the best experts on this subject based on the ideXlab platform.
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Durabilidad natural de madera de Teca (Tectona Grandis L.f.) procedente de Chanchamayo - Junín
'Universidad Nacional Agraria la Molina', 2020Co-Authors: Fabián Hidalgo, Karen NathalyAbstract:Universidad Nacional Agraria La Molina. Facultad de Ciencias Forestales. Departamento Académico de Industrias ForestalesEn el presente estudio se evaluó la resistencia a la degradación de la madera de Tectona Grandis L.f., procedente de la plantación de 33 años del fundo Génova, del IRD Selva - UNALM en Chanchamayo – Junín, considerando la madera de albura y duramen de rodajas distribuidas a tres niveles de altura del fuste en cinco árboles. Según la durabilidad natural determinada bajo referencia de la Norma ASTM D 2017-05, la madera frente a los hongos de pudrición blanca Pycnoporus sanguineus y Schizophyllum commune, se clasificó como resistente en el duramen y moderadamente resistente en la albura, con pérdidas de peso que incrementan desde la base al ápice del árbol. También, se determinó el contenido de extractivos totales según Normas TAPPI, utilizando etanol al 96 %, agua fría y agua caliente; este contenido resultó mayor en la zona basal del fuste predominando los solubles en etanol. Así mismo, se identificaron los metabolitos secundarios mediante marcha fitoquímica y un sistema de cromatografía líquida acoplada con espectrometría de masas, los cuales presentaron una distribución uniforme a lo largo del fuste, pero con mayor variedad en el duramen, donde se encontró dos flavanonas, una flavona, una chalcona, un estilbeno, cuatro naftoquinonas y una antraquinona diferente a tectoquinona. Por último, se cuantificó el contenido de polifenoles y capacidad antioxidante mediante los métodos Folin - Ciocalteu y ORAC respectivamente; propiedades que mostraron un comportamiento uniforme en el duramen, pero descendiente en la albura de la base al ápice del árbol. De esta forma, se encontró que el contenido de extractivos totales, polifenoles y capacidad antioxidante es inversamente proporcional a la pérdida de peso de la madera; siendo el contenido de polifenoles, el mejor indicador fitoquímico de la durabilidad natural de la madera de T. Grandis.In this study, the resistance to degradation of Tectona Grandis L.f. wood, from the 33 years plantation of the Genova estate, of the IRD Selva - UNALM in Chanchamayo - Junín, was evaluated considering the sapwood and heartwood of distributed slices at three levels of the shaft in five trees. distributed at three levels of the shaft. According to the natural durability determined under reference of the ASTM D 2017-05 Standard, wood against white rot fungi Pycnoporus sanguineus and Schizophyllum commune, was classified as resistant in the heartwood and moderately resistant in the sapwood, with weight losses that increase from the base to the apex of the tree. Too, the total extractives content was determined according to TAPPI Standards, using 96% ethanol, cold water and hot water; this content was higher in the basal zone of the shaft predominantly those soluble in ethanol. Likewise, secondary metabolites were identified by phytochemical gait and a liquid chromatography system coupled with mass spectrometry, which presented a uniform distribution along the shaft, but with greater variety in the heartwood, where two flavanones were found, one flavone, a chalcona, a stilbene, four naphthoquinones and a different anthraquinone than tectoquinone. Finally, the polyphenol content and antioxidant capacity were quantified using the Folin- Ciocalteu and ORAC methods respectively; properties that showed a uniform behavior in the heartwood, but descending in the sapwood of the base at the apex of the tree. In this way, it was found that the content of total extractives, polyphenols and antioxidant capacity is inversely proportional to the weight loss of the wood; being the polyphenol content, the best phytochemical indicator of the natural durability of T. Grandis wood.Tesi
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Durabilidad natural de madera de Teca (Tectona Grandis L.f.) procedente de Chanchamayo - Junín
'Baishideng Publishing Group Inc.', 2020Co-Authors: Fabián Hidalgo, Karen NathalyAbstract:Universidad Nacional Agraria La Molina. Facultad de Ciencias Forestales. Departamento Académico de Industrias ForestalesEn el presente estudio se evaluó la resistencia a la degradación de la madera de Tectona Grandis L.f., procedente de la plantación de 33 años del fundo Génova, del IRD Selva - UNALM en Chanchamayo – Junín, considerando la madera de albura y duramen de rodajas distribuidas a tres niveles de altura del fuste en cinco árboles. Según la durabilidad natural determinada bajo referencia de la Norma ASTM D 2017-05, la madera frente a los hongos de pudrición blanca Pycnoporus sanguineus y Schizophyllum commune, se clasificó como resistente en el duramen y moderadamente resistente en la albura, con pérdidas de peso que incrementan desde la base al ápice del árbol. También, se determinó el contenido de extractivos totales según Normas TAPPI, utilizando etanol al 96 %, agua fría y agua caliente; este contenido resultó mayor en la zona basal del fuste predominando los solubles en etanol. Así mismo, se identificaron los metabolitos secundarios mediante marcha fitoquímica y un sistema de cromatografía líquida acoplada con espectrometría de masas, los cuales presentaron una distribución uniforme a lo largo del fuste, pero con mayor variedad en el duramen, donde se encontró dos flavanonas, una flavona, una chalcona, un estilbeno, cuatro naftoquinonas y una antraquinona diferente a tectoquinona. Por último, se cuantificó el contenido de polifenoles y capacidad antioxidante mediante los métodos Folin - Ciocalteu y ORAC respectivamente; propiedades que mostraron un comportamiento uniforme en el duramen, pero descendiente en la albura de la base al ápice del árbol. De esta forma, se encontró que el contenido de extractivos totales, polifenoles y capacidad antioxidante es inversamente proporcional a la pérdida de peso de la madera; siendo el contenido de polifenoles, el mejor indicador fitoquímico de la durabilidad natural de la madera de T. Grandis.In this study, the resistance to degradation of Tectona Grandis L.f. wood, from the 33 years plantation of the Genova estate, of the IRD Selva - UNALM in Chanchamayo - Junín, was evaluated considering the sapwood and heartwood of distributed slices at three levels of the shaft in five trees. distributed at three levels of the shaft. According to the natural durability determined under reference of the ASTM D 2017-05 Standard, wood against white rot fungi Pycnoporus sanguineus and Schizophyllum commune, was classified as resistant in the heartwood and moderately resistant in the sapwood, with weight losses that increase from the base to the apex of the tree. Too, the total extractives content was determined according to TAPPI Standards, using 96% ethanol, cold water and hot water; this content was higher in the basal zone of the shaft predominantly those soluble in ethanol. Likewise, secondary metabolites were identified by phytochemical gait and a liquid chromatography system coupled with mass spectrometry, which presented a uniform distribution along the shaft, but with greater variety in the heartwood, where two flavanones were found, one flavone, a chalcona, a stilbene, four naphthoquinones and a different anthraquinone than tectoquinone. Finally, the polyphenol content and antioxidant capacity were quantified using the Folin- Ciocalteu and ORAC methods respectively; properties that showed a uniform behavior in the heartwood, but descending in the sapwood of the base at the apex of the tree. In this way, it was found that the content of total extractives, polyphenols and antioxidant capacity is inversely proportional to the weight loss of the wood; being the polyphenol content, the best phytochemical indicator of the natural durability of T. Grandis wood
Adzo Dzifa Kokutse - One of the best experts on this subject based on the ideXlab platform.
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decay resistance of togolese teak Tectona Grandis l f heartwood and relationship with colour
Trees-structure and Function, 2006Co-Authors: Adzo Dzifa Kokutse, Alexia Stokes, Henri Bailleres, Kouami Kokou, Christine BaudasseAbstract:Togolese teak (Tectona Grandis L.f) is highly resistant to pathogen attack, but variability in natural durability exists between trees of different ages, plantations and geographical zones. Therefore, further information concerning this parameter of wood quality is necessary; however, traditional testing methods are difficult and time-consuming to carry out. We tested the possibility of using colorimetry to determine durability in heartwood samples taken from a wide range of trees. Twelve hundred samples from 31 trees were exposed to four fungi: Pycnoporus sanguineus, Antrodia sp., Gloephylum trabeum, and Coriolus versicolor. Wood samples were grouped into three classes (inner, intermediate and outer heartwood). The colour parameters of each sample were then determined using the CIELAB (L*, a*, b*) system and results correlated with the %mass loss of wood after fungal attack. Tests showed that Antrodia sp. and C. versicolor resulted in <20% mass loss, whereas all samples were rated as durable or highly durable with regard to P. sanguineus and G. trabeum. Inner heartwood was found to be the most resistant to pathogen attack and outer heartwood the least. Measurements of colour showed that heartwood was lightest nearest the pith and darkness and redness increased towards the outer heartwood. Regressions of lightness with %mass loss in the durability tests were always highly significant, whereas a* and b* were not always significantly regressed with %mass loss. Therefore, the use of colorimetry as a tool to estimate short-term natural durability both rapidly and cheaply could be considered in the case of plantation grown teak wood.
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proportion and quality of heartwood in togolese teak Tectona Grandis l f
Forest Ecology and Management, 2004Co-Authors: Adzo Dzifa Kokutse, Alexia Stokes, Henri Bailleres, Kouami KokouAbstract:Although teak (Tectona Grandis L.f.) is an important indigenous timber species to south-east Asia, teak plantations have been established widely throughout the tropics and successfully in Togo since 1920. However, no studies exist concerning the quality of Togolese teak wood depending on age and stand situation. The heartwood proportion, modulus of elasticity (EL) and wood density at 12% moisture content of 80 trees of various ages from different ecological zones in Togo were examined. Results showed that the percentage of heartwood differed significantly in trees depending on the ecological zones. Density at 12% moisture content was significantly correlated to tree age and diameter at breast height. In juvenile wood, density was highly variable, but tended to increase before stabilising with age, whereas EL in adult wood was significantly greater than that in juvenile wood. # 2003 Elsevier B.V. All rights reserved.
Cuarezma, Jose Alejandro - One of the best experts on this subject based on the ideXlab platform.
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Informe de pasantia realizada en la empresa NICAFOREST PLANTATIONS, S.A., en las actividades de inventario y establecimiento de parcelas permanentes de monitoreo en plantaciones forestales de teca (Tectona Grandis L.F.)
2020Co-Authors: Cuarezma, Jose AlejandroAbstract:La pasantía fue realizada en la empresa NICAFOREST PLANTATIONS, S.A; ubicada en el municipio de Santo Tomás en el departamento de Chontales. Fue creada y conformada en el año 2011 por un grupo de inversionistas de socios europeos, que surgió mediante un programa de reforestación llamado mecanismo de desarrollo limpio (MDL), es un programa innovador para la reforestación en áreas Kyoto (tierras deforestadas en Nicaragua). En la actualidad la empresa cuenta 345 hectáreas de plantación forestal de la especie de Teca (Tectona Grandis L.f). El objetivo de realizar dicha pasantía es como requisito para optar al título de Ingeniero Forestal, se llevó a cabo en un periodo de seis meses, de noviembre del año 2018 hasta abril del año 2019. Se realizaron diversas actividades como medición de áreas de las plantaciones forestales de teca de pequeños productores, así mismos inventarios forestales, establecimiento de parcelas permanentes de monitoreo (PPM) y marcaje de árboles para raleo sanitario, las que son de importancia para el manejo silvicultural y monitoreo de plantaciones comerciales de Teca (Tectona Grandis L.f). Las plantaciones establecidas por la empresa tienen como objetivo la captura de carbono (CO2), dichas plantaciones son certificadas bajos los principios y criterios de Forest Stewardship Council (FSC) y Rainforest Alliance. Con esta pasantía fue posible adquirir mayores conocimientos que me permitió ampliar la experiencia técnica en labores reales en manejo de plantaciones forestales y ponerlos en práctica en el campo profesional, además se logró intercambiar conocimientos con el personal de operaciones y responsables del manejo de las plantaciones y de esa manera crear competencias en el ámbito laboral
Kouami Kokou - One of the best experts on this subject based on the ideXlab platform.
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decay resistance of togolese teak Tectona Grandis l f heartwood and relationship with colour
Trees-structure and Function, 2006Co-Authors: Adzo Dzifa Kokutse, Alexia Stokes, Henri Bailleres, Kouami Kokou, Christine BaudasseAbstract:Togolese teak (Tectona Grandis L.f) is highly resistant to pathogen attack, but variability in natural durability exists between trees of different ages, plantations and geographical zones. Therefore, further information concerning this parameter of wood quality is necessary; however, traditional testing methods are difficult and time-consuming to carry out. We tested the possibility of using colorimetry to determine durability in heartwood samples taken from a wide range of trees. Twelve hundred samples from 31 trees were exposed to four fungi: Pycnoporus sanguineus, Antrodia sp., Gloephylum trabeum, and Coriolus versicolor. Wood samples were grouped into three classes (inner, intermediate and outer heartwood). The colour parameters of each sample were then determined using the CIELAB (L*, a*, b*) system and results correlated with the %mass loss of wood after fungal attack. Tests showed that Antrodia sp. and C. versicolor resulted in <20% mass loss, whereas all samples were rated as durable or highly durable with regard to P. sanguineus and G. trabeum. Inner heartwood was found to be the most resistant to pathogen attack and outer heartwood the least. Measurements of colour showed that heartwood was lightest nearest the pith and darkness and redness increased towards the outer heartwood. Regressions of lightness with %mass loss in the durability tests were always highly significant, whereas a* and b* were not always significantly regressed with %mass loss. Therefore, the use of colorimetry as a tool to estimate short-term natural durability both rapidly and cheaply could be considered in the case of plantation grown teak wood.
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proportion and quality of heartwood in togolese teak Tectona Grandis l f
Forest Ecology and Management, 2004Co-Authors: Adzo Dzifa Kokutse, Alexia Stokes, Henri Bailleres, Kouami KokouAbstract:Although teak (Tectona Grandis L.f.) is an important indigenous timber species to south-east Asia, teak plantations have been established widely throughout the tropics and successfully in Togo since 1920. However, no studies exist concerning the quality of Togolese teak wood depending on age and stand situation. The heartwood proportion, modulus of elasticity (EL) and wood density at 12% moisture content of 80 trees of various ages from different ecological zones in Togo were examined. Results showed that the percentage of heartwood differed significantly in trees depending on the ecological zones. Density at 12% moisture content was significantly correlated to tree age and diameter at breast height. In juvenile wood, density was highly variable, but tended to increase before stabilising with age, whereas EL in adult wood was significantly greater than that in juvenile wood. # 2003 Elsevier B.V. All rights reserved.
