No abstract

The aim of this study was to evaluate the chemical, antioxidant, and antimicrobial activity of the essential oils as well as the anatomy of the aerial parts from Baccharis aracatubaensis, Baccharis burchellii, and Baccharis organensis owing to the therapeutic potential of Baccharis. The volatile constituents were analyzed using GC/MS, the antioxidant activity was evaluated by oxygen radical absorbance capacity (ORAC FL ) and DPPH assays, and the antimicrobial activity by a microdilution technique. Of the 56 compounds identified, only seven (β-caryophyllene, γ-muurolene, bicyclogermacrene, β-germacrene, spathulenol, τ-muurolol, and α-cadinol) were common in the three specimens studied. Of these, γ-muurolene was found abundantly in B. aracatubaensis, while bicyclogermacrene was abundant in B. burchellii and B. organensis. The essential oils exhibited antioxidant activity in the ORAC FL (> 500.0 μmol TE g À 1 ) and DPPH assays. However, they did not exhibit any antimicrobial activity. Secretory ducts and flagelliform glandular trichomes were observed in the anatomical study of all the Baccharis species studied.

Several species of the genus Piper are known in Brazilian folk medicine as having diuretic activity. So, we propose to investigate the acute diuretic activity and the possible toxic effects of Piper glabratum Kunth, popularly known as false Jaborandi. Additionally, we propose to check whether there is any correlation between the biological activities of the crude extract (MEPG) and its 2-methoxy-4,5-methylenedioxy-trans-cinnamoyl-pyrrolidine (MMCP) in Wistar rats. The MEPG was fractioned by chromatography column and the MMCP was identified by analyses of 1H and 13C RMN spectral data and correlations. Both MEPG and MMCP were assayed for diuretic activity. The preparations obtained were orally administered in a single dose to rats. The urine excretion, pH, density, conductivity, and content of Na+, K+, Cl−, and HCO3 − were measured in the urine of saline-loaded animals. Additionally, acute toxicity of the extract was also evaluated. MMCP at doses of 30 mg/kg was able to increase the urine volume, pH, and HCO3 − excretion. Moreover, high dosage of MEPG showed important liver toxicity and elevated mortality when injected intraperitoneally. The results indicate that the MMCP shows important diuretic properties when administered in Wistar rats. Additionally, MEPG can induce important acute toxicity if given in high doses.

ABSTRACT:The purpose of this study was to evaluate the effect of heat treatment on MDF panels, aiming mainly to improve their dimensional stability. The panels were obtained from the local market and were manufactured using as raw material Eucalyptus sp. and synthetic urea-formaldehyde resin. Twenty-five samples were used in the tests, which were subdivided into different groups for the thermal treatment in an oven and submitted to temperatures between 160 and 180 °C during a period between 6 and 12 min. We also evaluated the performance of the control samples, i.e., those that have not undergone any treatment. After the treatment, samples were produced for physical tests (density, water absorption -at 2 and 24 h, thickness swelling, residual and hygroscopic swelling -at 2 and 24 h) and mechanical tests (static bending and screw withdrawal resistance). For the physical tests after the treatment, the sample dimensions were reduced to 15 x 15 x 1.5 cm thick, and for the mechanical tests they were sawn in dimensions of 7.5 x 42 x 1.5 cm thick. The results of the physical properties showed that the treatments used did not increase the dimensional stability. The mechanical properties were also not affected by the heat treatment.Keywords: wood panels, thermal rectification, dimensional stability.Efeito do tratamento térmico sobre as propriedades físicas e mecânicas de painéis MDF RESUMO: O objetivo deste trabalho foi avaliar o efeito do tratamento térmico em painéis de MDF, visando principalmente à melhoria de sua estabilidade dimensional. Os painéis foram obtidos junto ao comércio local, fabricados com matéria-prima Eucalyptus sp. e resina sintética ureia-formaldeído. Foram utilizadas vinte e cinco amostras para os ensaios, sendo estas subdivididas em diferentes grupos para o tratamento térmico em estufa utilizando as temperaturas de 160 e 180 o C, por um período de 6 e 12 min. Juntamente, avaliou-se o desempenho de amostras testemunhas, ou seja, as quais não foram submetidas a nenhum tipo de tratamento. Após o tratamento, foram produzidas amostras para os ensaios físicos (massa especifica, absorção de água -às 2 e 24 h, inchamento em espessura, residual e higroscópico -às 2 e 24 h) e mecânicos (flexão estática e resistência ao arrancamento de parafusos). Para os ensaios físicos após o tratamento, as amostras foram reduzidas as dimensões de 15 x 15 x 1,5 cm em largura, comprimento e espessura e, para os ensaios mecânicos foram serradas nas dimensões de 7,5 x 42 x 1,5 cm em largura, comprimento e espessura. Os resultados das propriedades físicas indicaram que os tratamentos utilizados não proporcionaram aumento na estabilidade dimensional. As propriedades mecânicas também não foram afetadas pelo tratamento térmico. Palavras-chave: painéis de madeira, termorretificação, estabilidade dimensionalRecebido em outubro/2015; Aceito em março/2016.

Baccharis (Asteraceae): Chemical Constituents and Biological Activities -[162 refs.]. -(RAMOS CAMPOS*, F.; BRESSAN, J.; GODOY JASINSKI, V. C.; ZUCCOLOTTO, T.; DA SILVA, L. E.; BONANCIO CERQUEIRA, L.; Chem. Biodiversity 13 (2016) 1, 1-17, http://dx.