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The objective of this study was to evaluate the acaricidal and larvicidal activities of essential oil (EO) from fruits, leaves and flowers of garlic wood on cattle tick [Rhipichephalus (Boophilus) microplus]. The fruits were harvested from May to June (2015) and the leaves and flowers in December (2015). The EO was obtained by hydrodistillation (2h) and identified by GC/MS. Bioassays consisted of Adult Immersion Test and Larval Immersion Test. The results made the following major compounds evident: 2,3,5-trithiahexane (35.29%) in fruits, dimethyl sulfide (42.42%) in leaves and methanethiol (44.91%) in flowers. The EOs from fruits, leaves and flowers showed high activity on the tick larval cycle, presenting LD 99.9 of (0.23 ± 0.01 mg/mL), (2.15 ± 0.11 mg/mL) and (0.08 ± 0.00 mg/mL), respectively. However, when we compared different phases of cattle tick's live cycle, EO from fruits was more active on females' mortality, and EO from leaves was more efficient on the egg hatching inhibition, whereas EO from flowers presented better results on bovine tick larva. Thus, garlic wood (Gallesia integrifolia), a native plant of the Atlantic forest can be considered as a promising natural agent to control bovine tick.

The Brazilian ginseng Pfaffia glomerata (Spreng.) Pedersen belongs to the Amaranthaceae family and has as its main component β-ecdysone, a phytoecdysteroid, found in the roots, stem, flowers and leaves of the plant. In the last years sustainability and the environment concern were decisive for the emerging supercritical fluid extraction and pressurized fluid extraction technologies to obtain biocomposites from the plant. These extraction technologies use solvents (CO2, ethanol and water) and uses as controllable parameters pressure, flow, time and temperature. The combination of these factors generates atoxicity, no residue in the final extract and have a reduced energy cost and an excellent extraction yield. This work reviews the literature from 2007 to 2020 on the use of clean technology to obtain chemical biocomposites of interest in the areas of biology, agronomy, food and pharmaceutics. It is was concluded that the supercritical fluid extraction and pressurized liquid extraction extracts were very efficient in obtaining β-ecdysone, since both presents low energy consumption, uses environmentally correct solvents which reduces harmful effects on the environment. Finally, to choose the best technology for extraction of other biocomposites depends on the chemical compound of interest.

A Pfaffia glomerata (Spreng.) Pedersen é uma planta medicinal conhecida como ginseng brasileiro. Tradicionalmente, apenas as suas raízes são utilizadas para fins comerciais, em função do seu teor conhecido de β-ecdisona. Neste trabalho, as concentrações de β-ecdisona em infusões aquosas de folhas, flores, raízes e caules de indivíduos de seis meses e de três anos de idade foram determinadas por cromatografia líquida de alta eficiência (HPLC). As análises foram realizadas em HPLC LC-4000 Jasco®, com uma coluna de fase reversa (Fortis®, C18, 250 × 4,6 nm, 5 μm), e a absorbância foi medida em 245 nm. A fase móvel foi uma mistura de metanol e água. O volume de injeção foi de 20 μL e a vazão de 1 mL/min. O tempo total da corrida foi de 15 min. A maior concentração foi obtida para as folhas do indivíduo de três anos de idade (1,65 ± 0,14%) seguida pelas folhas do indivíduo de seis meses (1,07 ± 0,1%). As amostras de flores, de raiz e de caule do indivíduo de três anos, apresentaram: 1,14 ± 0,10%, 0,68 ± 0,05% e 0,62 ± 0,06% de β-ecdisona, respectivamente. Nas amostras do indivíduo de seis meses foram observados teores det0,37 ± 0,12%, 0,37 ± 0,12% e 0,56 ± 0,02% para flores, raiz e caule respectivamente. Os resultados sugerem que as partes aéreas da planta também podem ser de interesse comercial, visto que as folhas apresentaram as maiores concentrações nas duas idades.

The refractive index and the temperature coefficient of the optical path length change of tellurite ͑80TeO 2 : 20Li 2 O͒ and chalcogenide glasses ͑72.5Ga 2 S 3 : 27.5La 2 O 3 ͒ were determined as a function of temperature ͑up to 150°C͒ and wavelength ͑in the range between 454 and 632.8 nm͒. The tellurite glass exhibits the usual refractive index dispersion in the wavelength range analyzed, while anomalous refractive index dispersion was observed for the chalcogenide glass between 454 and 530 nm. The dispersion parameters were determined by means of the single-effective oscillator model. In addition, a strong dependence of the temperature coefficient of the optical path length on the photon energy and temperature was found for the chalcogenide glass. The latter was correlated to the shift of the optical band gap ͑or electronic edge͒ with temperature, which was interpreted by the electron-phonon interaction model.

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The essential oil (EO) of pink pepper has important biological properties that can enhance its application in the pharmaceutical, cosmetic and food industries. The objective of this study was to characterize the EO of pink pepper seeds in terms of their chemical composition and thermophysical properties. Certified pink pepper seeds obtained commercially were used. The EO was extracted by hydrodistillation and chemically characterized in a gas chromatograph coupled to mass spectrometer (GC/MS). The thermoanalytical characterization was performed on a simultaneous high resolution equipment, and the Thermogravimetric Analysis (TG) and Differential Scanning Calorimetry (DSC) were used to determine the physical-chemical and kinetic properties of the OE in the room temperature range up to 250 ºC in the 20 ºC.min-1 ratio under nitrogen atmosphere. The Arrhenius kinetic model was applied to determine the activation energy of the EO. A total of 51 chemical compounds were detected in the pink pepper EO, of which 42 compounds were identified (54.7% of monoterpene compounds and 45.3% sesquiterpenes). The major components were β-pinene (26.80%), germacrene D (11.25%), sabinene (11.13%) and terpinen-4-ol (8.59%). The thermogravimetric analysis indicated a single stage of thermo-degradation of the pink pepper EO between 74.8 ºC and 184.7 ºC, being an endothermic peak in the physical transition of vaporization. The variation of enthalpy and activation energy of EO were found with values of  = - (39.8 ± 9.5) KJ.Kg-1 and  = - (2,546 ± 0.033) KJ.mol-1, respectively. The data presented in the thermogravimetric analysis of pink pepper seeds EO allowed observing important thermal parameters for the definition of industrial processes that can use it as raw material, so that its biological activities can remain stable under controlled temperature conditions and below the range degradation.

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