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The search for natural wood preservatives is becoming increasingly evident due to industrial preservatives presenting several environmental restrictions, such as soil, water and ecosystems contamination. Therefore, the objective of the present study is to evaluate the antifungal activity of Cinnamomum zeylanicum bark natural extract subjected to rotting fungi. In order to obtain the aqueous extract, two methods were performed with different concentrations, 50 and 100 g L-1, using Pycnoporus sanguineus e Gloeophyllum trabeum, mycelium. In the first, we kept the C. Zeylanicum bark with distilled water for 1 h in water bath and, in the second, the same concentrations were used, however, this was kept in a recipient for 24 h. Then, the extract was subjected to sterilization along with the BDA medium in autoclave at 120ºC for 20 min, they were then put in petri dishes for later evaluation of the mycelium root growth compared with the control. The fungi Pycnoporus sanguineus presented higher fungal activity, obtaining total inhibition of all treatments and extract concentrations, however, for the fungi Gloeophyllum trabeum, the 100 g L-1 concentration warmed in water bath obtained a better result than the others. Therefore, it can be concluded that the Cinnamomum zeylanicum aqueous extract presented inhibitory potential. Considering this, we suggest that more studies with this thematic should be carried out, seeking to discover new alternatives for wood preservatives that are less damaging to the environment and to mankind.

A espectroscopia no infravermelho próximo (Near Infrared Spectroscopy, NIRS) é uma técnica não destrutível, rápida e acurada, aplicável em muitas amostras e tem se mostrado como uma ferramenta eficiente na determinação das propriedades químicas, anatômicas, físicas e mecânicas da madeira. O objetivo deste estudo foi desenvolver modelos de calibração NIRS para as características químicas da madeira de Eucalyptus benthamii. Para o desenvolvimento dos modelos de calibração toretes de 87 árvores, sendo 75 de E. benthamii, quatro de E. dunnii, quatro de E. grandis e quatro de E. saligna foram transformadas em cavacos. Parte deste material serviu para as análises de cinzas, extrativos, lignina total e Klason e holocelulose, outra parte foi moída para aquisição dos espectros, que posteriormente foram correlacionados aos valores laboratoriais. A calibração do modelo foi determinada por análise de regressão dos mínimos quadrados parciais (PLS). A seleção dos modelos foi tomada com base nos critérios estatísticos de coeficiente de determinação (R²), erro médio da validação cruzada (RMSECV), desvio residual de previsão (RPD) e do número de variáveis latentes (VLs). A composição química da madeira de E. benthamii corrobora os resultados evidenciados na literatura para os eucaliptos. Os modelos de calibração apresentaram ajustes satisfatórios para o teor de holocelulose (R2=0,82), lignina total (R2=0,74) e lignina Klason (R2=0,82) e a sua utilização comercial é recomendada para predição de amostras desconhecidas. A técnica NIRS se mostrou promissora para predizer a qualidade da madeira de Eucalyptus benthamii para a indústria de celulose. Near Infrared Spectroscopy (NIRS) is a non-destructible, fast, and reliable technique that can be applied in many different samples. NIR has been shown to be an efficient tool in determining the chemical, anatomical, physical, and mechanical properties of wood. The aimed of this study was to development calibration models for the wood of Eu-calyptus benthamii as to its chemical constitution. For the development of the calibration models 87 trees were used (75 of E. benthamii, 4 of E. dunnii, 4 of E. grandis, and 4 of E. saligna). A portion of the sample was used for analysis of ash, extractives, lignin and holocellulose content. Another portion was milled and used to acquire the spectra, which were later correlated to laboratory values. Calibration of the model was determined by partial least squares regression analysis (PLS). Selection of the best models was based on the following statistical criteria: coefficient of determination (R²), mean cross-validation error (RMSECV), residual forecast deviation (RPD), and number of latent variables (VLs). The chemical composition of E. benthamii wood agrees with the results evidenced in the literature for Eucalyptus. NIRS calibration models presented satisfactory adjustments for holocellulose content (R2 = 0.82), total lignin content (R2 = 0.74) and Klason lignin content (R2 = 0.82). The NIRS models developed in this study present a viable commercial tool for characterization of samples of Eucalyptus benthamii wood for the cellulose industry.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico Outra Agência O uso de práticas não destrutivas como a espectroscopia na região do infravermelho próximo (Near Infrared Spectroscopy, NIRS) tem crescido e se destacado em qualificações de processos e produtos, e também em programas de melhoramento genético florestal, pois permitem a seleção de árvores ainda no povoamento. O objetivo deste estudo foi utilizar o NIR como ferramenta na análise da qualidade da madeira e seleção genética de árvores de Eucalyptus benthamii Maiden & Cambage com vistas à produção de celulose. Para o desenvolvimento dos modelos de calibração, 87 árvores, sendo 75 de E. benthamii, quatro de E. dunnii, quatro de E. grandis e quatro de E. saligna foram transformadas em cavacos. Parte desse material serviu para as análises de lignina Klason e totais, holocelulose e densidade básica, outra parte foi moída para aquisição dos espectros, que posteriormente foram correlacionados aos valores laboratoriais. A calibração do modelo foi determinada por análise de regressão dos mínimos quadrados parciais (PLS). Os modelos de calibração apresentaram ajustes satisfatórios para a lignina Klason (R2=0,82), lignina total (R2=0,74), teor de holocelulose (R2=0,82) e densidade básica de madeira (R2=0,73) e a sua utilização comercial é recomendada para predição de amostras desconhecidas. A técnica NIRS se mostrou promissora na predição da qualidade da madeira de Eucalyptus benthamii para a indústria de celulose e pode ser utilizada para acelerar o programa de melhoramento genético do E. benthamii. The use of non-destructive techniques such as near infrared spectroscopy (NIRS) has become of great interest in characterization of wood quality. Additionally, non-destructive techniques offer great application in genetic improvement programs because they aid selection of trees that are still in the stands. The objective of this study was to assess the suitability of NIRS as a tool in the analysis of wood quality and genetic selection of Eucalyptus benthamii Maiden & Cambage clones used for production of cellulose. Eighty-seven trees (75 of E. benthamii, 4 of E. dunnii, 4 of E. grandis, and 4 of E. saligna) were used for the development of calibration models. Wood samples were analyzed for Klason lignin, total lignin, holocellulose, and basic density. A sub-sample was milled and used to acquire the spectra, which were then compared against values obtained from standard laboratory techniques. Model calibration was determined by partial least squares (PLS) regression analysis. The values observed for anatomical and chemical traits of Eucalyptus benthamii wood remained within the range considered appropriate for Klason lignin (R2 = 0.82) and total lignin content (R2 = 0.74). NIRS calibration models presented satisfactory adjustments for holocellulose content (R2 = 0.82) and wood density (R2 = 0.73). The NIRS models developed in this study offer the cellulose industry a viable commercial tool that can be used for characterization of samples of Eucalyptus benthamii wood. The accuracy of the models warrants their use in programs to accelerate the genetic improvement of E. benthamii.

The aim of this study was to evaluate the effect of boron compounds utilized in wood impregnation, its influence on the physical properties of eucalyptus wood and to verify the veracity of the equilibrium moisture content obtained by the Simpson’s equation. The wood impregnation consisted of 4% and 8% of boron compound concentrations and was applied to the wood of three Eucalyptus clones. To analyze the equilibrium moisture content, the test samples were acclimatized at different temperatures and relative humidity. The dry density, shrinkage, and anisotropy coefficient for all the wood samples were measured. The presence of the boron compound in impregnated wood enhanced the dry density and radial shrinkage in one of the Eucalyptus clones. The equilibrium moisture content dropped when the 4% boron compound concentration was used to impregnate the wood. The Simpson’s equation must be applied with caution for ascertaining the equilibrium moisture content measurements because different values are achieved when compared with the findings of the acclimatized chambers. O objetivo deste estudo foi avaliar o efeito dos compostos de boro utilizados na impregnação, sua influência sobre as propriedades físicas da madeira de eucalipto e verificar a veracidade do teor de umidade de equilíbrio obtido pela equação de Simpson. A impregnação consistiu da aplicação de soluções de 4 e 8% de concentração de compostos de boro na madeira de três clones de eucalipto. Para analisar o conteúdo de umidade de equilíbrio da madeira, as amostras foram aclimatadas em diferentes temperaturas e umidades relativas. A densidade anidra, contração e coeficiente de anisotropia para todas as amostras de madeira foram determinados. A presença de composto de boro na madeira impregnada incrementou a densidade anidra e o inchamento radial para todos os clones de eucalipto testados. O teor de umidade de equilíbrio diminuiu quando a concentração de 4% de compostos de boro foi usada. A equação de Simpson deve ser aplicada com cautela para verificar as medições de conteúdo de umidade de equilíbrio, uma vez que valores diferentes são obtidos quando comparados aos da câmara climatizada.

High toxicity of the preservatives most frequently used in wood treatment and the resulting risks of handling pose a threat to small producers and to the environment. In an attempt to mitigate these problems, the present study was conducted with the objective of evaluating the preservative effect of tannic extract on biodeterioration of Acacia mearnsii wood. For this purpose, untreated and preserved specimens, some with tannin extract and some with a preservative mixture based on CCB (Chromated Copper Borate), were submitted to accelerated rotting trials with the fungus that causes white rot (Pycnoporus sanguineus) for 16 weeks. The evaluations were made with a basis on weight loss and chemical components analysis, and they showed that the natural resistance of Acacia wood is moderate when exposed to the white rot fungus. The tannin concentrations showed similar effects to those of the CBB mixture in all evaluations, i.e., they significantly increased the biological resistance of the material, which started to be classified as very resistant to the fungus. Overall, the results suggest that tannin can be considered as a potential natural preservative product.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The objective of study was to characterize wood deterioration in samples with conventional and natural treatments using Rockwell hardness and spectroscopy. Five acacia trees were used to make 70 samples, of which 20 were treated with tannin and 10 with a Copper Chrome Borate mixture (CCB), while 10 samples exposed to fungus received no treatment and 30 were used as unexposed controls. The specimens for preservative treatments were saturated with the solutions, using full cell pressure in autoclave. Shortly after the treatment, the samples were exposed to Pycnoporus sanguineus for 16 weeks, using the accelerated rot test. Then, deterioration was evaluated by spectroscopy and Rockwell hardness. CCB was the most suitable to preserve wood hardness, followed by treatments with 10 and 5% of tannin, and all treatments presented similar values indicating they produced similar effects. Medium infrared spectroscopy analysis indicated that the material treated with 5 and 10% tannin showed the greatest similarity to the spectra from control samples. O presente estudo teve como objetivo utilizar a dureza Rockwell e espectroscopia para caracterizar a deterioração da madeira com tratamento convencional e natural. Para tal, cinco árvores de acácia foram utilizadas para a confecção de 70 amostras, sendo 20 para tratamentos com tanino, 10 para tratamento com mistura de Borato de Cobre Cromatado (CCB), 10 para posterior avaliação da resistência natural da madeira ao fungo e 30 controles não expostos. Os corpos de prova destinados aos tratamentos preservativos foram impregnados com as soluções utilizando o método de pressão de célula cheia em autoclave. Em seguida, as amostras foram expostas ao fungo Pycnoporus sanguineus por 16 semanas, por meio de ensaio de apodrecimento acelerado. Passado o período do ensaio, a deterioração foi avaliada pela espectroscopia e dureza Rockwell. A mistura CCB foi a mais adequada para preservar a dureza da madeira, seguida dos tratamentos com 10 e 5% de tanino, todos os tratamentos apresentaram valores similares indicando que produziram efeitos semelhantes. A análise por espectroscopia no infravermelho médio indicou que o material tratado com 5 e 10% de tanino apresentou a maior similaridade com os espectros das amostras controle.

This study aimed to test the hypothesis regarding the quality of Hovenia dulcis fence posts, which states that it varies according to the treatment period when subjected to the sap displacement method.. The experiment began with 15 round fence posts distributed vertically in tank containing copper sulfate, sodium dichromate and boric acid (CCB) solution at 2.5% concentration. In order to verify the influence of time on the efficiency of the method, the posts stayed in the preservative solution for periods of 3, 6, 9, 12 and 15 days, which were assessed. Penetration and retention in three positions were analyzed, which corresponded to the regions of base, middle and top parts. With regards to treated wood, samples of each piece were prepared for testing in field test. Then, weight loss and bending properties were assessed. According to the results of penetration and retention, wood treated on the period of 15 days is the only one that can be used directly with the soil. After assessment of the weight loss, the periods of 12 and 15 days of treatment increased the classification of wood from moderately to strong resistant. The bending test showed significant reduction in rigidity and strength of the material, even in the treated ones, which demonstrates that the forest environment in which samples were exposed promoted the process of wood decomposition.