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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.

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.

O presente estudo tem como objetivo avaliar as propriedades biológicas, por meio de ensaio de apodrecimento acelerado com fungos xilófagos, em chapas aglomeradas de casca de arroz (Oryza sativa L) coladas com adesivo à base de tanino-formaldeído. Para tanto, foram utilizadas casca de arroz na forma natural e processada em moinho de martelo, compactadas a diferentes massas específicas (0,65; 0,95 e 1,15 g.cm-³) e aplicando-se teores de adesivos de 7, 10 e 13%, totalizando 54 chapas. Os resultados de perda de massa foram submetidos ao teste de correlação simples de Pearson e analisados por regressão. De acordo com os requisitos da norma ASTM D-2017 (2005), os testes biológicos, para todos os tratamentos, foram classificados como resistentes ao fungo Trametes versicolor, podridão branca. Já para o fungo Gloeophyllum trabeum a maioria dos tratamentos foram classificados como moderadamente resistente. Portanto, a casca de arroz mostra-se como uma alternativa de elevado potencial para a manufatura de chapas de maior resistência aos fungos apodrecedores de madeiras.Palavras-chave: massa específica, correlação simples de Pearson, fungos apodrecedores. BIOLOGICAL PROPERTIES OF RICE HUSK PARTICLEBOARD MANUFACTURED WITH TANNIN-FORMALDEHYDE ABSTRACT:Resistance to decay fungi Trametes versicolor and Gloephyllum trabeum of panels produced with rice husk and tannin - formaldehyde adhesive was evaluated. In the production of the panels, rice hulls were used in its natural form or hammer milled, compacted at different densities (0.65, 0.95 and 1.15 g/cm³) and with adhesives levels of 7, 10 and 13 % (based on the ovendry weight of the particles. The results were submitted to the Pearson correlation test and analyzed by regression. According to the requirements of ASTM D- 2017 (2005), the biological tests for all treatments were classified as resistant to white rot ungus Trametes versicolor. For the brown rot fungus Gloeophyllum trabeum, most treatments were classified as moderately resistant. Therefore, rice husk can be a high potential alternative to for the manufacture of particleboards for greater resistance to decay wood fungi.Keywords: specific gravity, simple Pearson correlation, decay fungi.

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.