RESUMEN Bixa orellana L. es ampliamente utilizado como un tinte y tiene otras propiedades que han sido poco estudiadas, especialmente en relación con las hojas. Este artículo evalúa cómo el secado B. orellana L. influye en las propiedades de los aceites esenciales (EOs) extraídos de sus hojas. El material vegetal recogido se sometió al horno de secado por aire convectivo a temperaturas de 35, 45 y 55 °C. Los perfiles químicos fueron determinados por GC-MS. Se aplicaron modelos matemáticos para representar el proceso de secado y el análisis estadístico realizado utilizando el software Statistica 10. Las EO se obtuvieron a través de la técnica de hidrodestilación con verificación de propiedades fisicoquímicas y actividad antimicrobiana. Para el ensayo de toxicidad se aplicó el bioensayo a Artemia salina. A través de los resultados obtenidos fue posible determinar el modelo matemático que se ajustaba mejor. Se observaron diferencias significativas en las propiedades de los EO. La temperatura de 45 °C permitió obtener el mejor rendimiento de EO, porque la actividad antimicrobiana fue más eficiente. Este estudio afirma a través de las actividades analizadas que la temperatura de secado influye en las propiedades fisicoquímicas y biológicas de las EO. Estudios como este evalúan el mejor modelo matemático para predecir el secado, así como las temperaturas específicas que influyen en las propiedades del producto obtenido.

SUMMARY Bixa orellana L. is widely used as a dye, and other properties are still little studied, especially in relation to leaves. This article evaluates how drying B. orellana L. influences the properties of essential oils (EOs) extracted from their leaves. The collected plant material was submitted to convective air-drying oven at temperatures of 35, 45 and 55 °C. Chemical profiles were determined by Gas Chromatography-Mass Spectrometry (GC-MS). Mathematical models were applied to represent the drying process and statistical analysis performed using Statistica 10 software. The EO's were obtained through the hydrodistillation technique with verification of physicochemical properties and antimicrobial activity by the Disc Diffusion Method. For the toxicity test, the bioassay was applied to Artemia salina. Through the results obtained it was possible to determine that the mathematical model of Verma was the one that best fitted the experimental data. Significant differences in the properties of EO's were observed. The temperature of 45 °C allowed obtaining the best EO yield, still presenting the most efficient antimicrobial activity. This study states through the activities analyzed that the drying temperature influences the physicochemical and biological properties of the EO's, thus requiring studies such as this one that evaluate the best mathematical model to predict drying as well as the specific temperatures that influence the properties of the product obtained.

RESUMO: O objetivo deste estudo foi investigar o efeito anestésico dos óleos essenciais (EOs) de Lippia alba (quimiotipos citral e linalool - EOLA-C e EOLA-L respectivamente) e Lippia origanoides (quimiotipo carvacrol- EOLO-Ca) em juvenis de tambaqui (Colossoma macropomum). As concentrações testadas dos EOs de L. alba e L. origanoides foram: 25, 50, 100 ou 200 μL/L. O tempo para atingir os estágios de sedação, anestesia profunda, recuperação e frequência ventilatória foram monitorados em cada concentração de EO. Os resultados indicam que todas as concentrações testadas dos OE induziram a anestesia do tambaqui e que a frequência ventilatória foi alterada pelos EOs. L. origanoides mostrou o tempo mais rápido para induzir sedação e anestesia, mas os tempos de recuperação foram longos. EO L. alba (citral 100 μL/L e linalol 200 μL/L) pode ser utilizado como anestésico em juvenis de tambaqui, pela eficiência em anestesiar e recuperar.

ABSTRACT: The aim of this study was to investigate the anesthetic effect of the essential oils (EOs) of Lippia alba (citral and linalool chemotypes, EOLA-C and EOLA-L respectively) and Lippia origanoides (chemotype carvacrol, EOLO-Ca) on tambaqui (Colossoma macropomum) juveniles. The tested concentrations of the L. alba and L. origanoides EOs were: 25, 50, 100, and 200 μL/L. Time required to reach the stages of sedation, deep anesthesia, and recovery, as well as ventilatory frequency, were monitored for each EO concentration. The results indicated that all EO concentrations tested induced tambaqui anesthesia and that the ventilatory frequency was altered by the EOs. L. origanoides showed the shortest time to induce sedation and anesthesia, but had long recovery times. L. alba EO (citral 100 μL/L and linalool 200 μL/L) can be used to efficiently anaesthetise tambaqui juveniles with an efficient recovery.

ABSTRACT Leishmaniasis is a disease that affects millions of people and it is an important public health problem. The drugs currently used for the treatment of leishmaniasis present undesirable side effects and low efficacy. In this study, we evaluated the in vitro activity of Melampodium divaricatum (MD-EO) and Casearia sylvestris (CS-EO) essential oils (EO) against promastigote and amastigote forms of Leishmania amazonensis. Sesquiterpenes E-caryophyllene (56.0%), germacrene D (12.7%) and bicyclogermacrene (9.2%) were identified as the main components of MD-EO, whereas E-caryophyllene (22.2%), germacrene D (19.6%) and bicyclogermacrene (12.2%) were the main constituents of CS-EO. CS-EO and E-caryophyllene were active against promastigote forms of L. amazonensis (IC50 24.2, 29.8 and 49.9 µg/mL, respectively). However, MD-EO, CS-EO and E-caryophyllene were more active against amastigote forms, with IC50 values of 10.7, 14.0, and 10.7 µg/mL, respectively. E-caryophyllene presented lower cytotoxicity against macrophages J774-A1 (CC50 of 62.1 µg/mL) than the EO. The EOs and E-caryophyllene should be further studied for the development of new antileishmanial drugs.

Abstract The objective of this work was to analyze the content and the chemical diversity of the essential oil (EO) of 22 Eplingiella fruticosa plants collected in Sergipe, Brazil. EOs were obtained from dry leaves by hydrodistillation and analyzed by GC/MS-FID. The mean EO contents ranged from 0.75 to 1.28%. The compounds found in greater amounts formed two clusters. The first cluster consisted of 15 plants and presented bicyclogermacrene (6.29-16.24%), spathulenol (7.59-15.23%), β-caryophyllene (5.77-12.97%), and caryophyllene oxide (5.00-11.90%) as major compounds. The second cluster consisted of seven plants and had 1,8-cineole (8.96-15.51%), α-pinene (5.46-13.77%), and camphor (4.08-11.40%) as major compounds. Results indicate chemical variability of the EO among E. fruticosa plants from the state of Sergipe. This information may assist in conservation strategies by providing data for investigation of biological activities of EO.

Há quase duas décadas, no Brasil, vêm sendo realizados estudos que revelam que os reservatórios hidrelétricos produzem gases biogênicos, principalmente o metano (CH4) e o dióxido de carbono (CO2), provenientes da decomposição orgânica da biomassa alagada. Observa-se que esse fenômeno é bastante complexo devido a uma gama de variáveis que possuem diferentes graus de interdependência e que influenciam diretamente ou indiretamente nas emissões de gases de efeito estufa (GEE). O objetivo deste trabalho é determinar o grau de relacionamento entre os fluxos difusivos de CO2, CH4 e variáveis ambientais dos Reservatórios Hidrelétricos de Furnas, Itumbiara e Serra da Mesa, através da análise estatística dos dados. Os reservatórios hidrelétricos estão situados no Bioma Cerrado, localizado no Planalto Central do Brasil. A escolha da região deu-se devido a sua importância no contexto nacional, já que corresponde a uma área de aproximadamente dois milhões de quilômetros quadrados, e, nela estão inseridas duas bacias (Bacia do Paraná e Bacia do Tocantins-Araguaia), com a maior capacidade instalada de energia elétrica do país. Esta duas bacias juntas abrangem 23% do território nacional. Neste estudo os resultados revelam que o CH4 apresentou correlação negativa, significativa e moderada com o CO2 e com a profundidade. Observou-se ainda correlação positiva e moderada com pH, temperatura da água e velocidade do vento. O CO2 apresentou correlação negativa, significativa e moderada com pH, com a velocidade do vento, temperatura da água e temperatura do ar. Observou-se também correlação positiva e moderada do CO2 com a temperatura da água. A complexidade do fenômeno de emissão dificilmente ocorrerá pelo entendimento simultâneo de todos os fatores, devido às dificuldades de acessar e analisar todas as variáveis que realmente têm implicação direta nesta produção/emissão de GEE.

For almost two decades, studies have been under way in Brazil, showing how hydroelectric reservoirs produce biogenic gases, mainly methane (CH4) and carbon dioxide (CO2), through the organic decomposition of flooded biomass. This somewhat complex phenomenon is due to a set of variables with differing levels of interdependence that directly or indirectly affect greenhouse gas (GHG) emissions. The purpose of this paper is to determine, through a statistical data analysis, the relation between CO2, CH4 diffusive fluxes and environmental variables at the Furnas, Itumbiara and Serra da Mesa hydroelectric reservoirs, located in the Cerrado biome on Brazil's high central plateau. The choice of this region was prompted by its importance in the national context, covering an area of some two million square kilometers, encompassing two major river basins (Paraná and Tocantins-Araguaia), with the largest installed power generation capacity in Brazil, together accounting for around 23% of Brazilian territory. This study shows that CH4 presented a moderate negative correlation between CO2 and depth. Additionally, a moderate positive correlation was noted for pH, water temperature and wind. The CO2 presented a moderate negative correlation for pH, wind speed, water temperature and air temperature. Additionally, a moderate positive correlation was noted for CO2 and water temperature. The complexity of the emission phenomenon is unlikely to occur through a simultaneous understanding of all the factors, due to difficulties in accessing and analyzing all the variables that have real, direct effects on GHG production and emission.

Chrysopogon zizanioides (L.) Roberty, Poaceae, is a plant widely used in northeast Brazil in folk medicine for the treatment of various pathological conditions, including inflammatory pain. The present study evaluated the antinociceptive and anti-inflammatory effects of C. zizanioides essential oil (EO) in rodents. EO was further characterized by GC/MS. The major components of EO were identified as khusimol (19.57%), E-isovalencenol (13.24%), α-vetivone (5.25%), β-vetivone (4.87%) and hydroxy-valencene (4.64%). Following intraperitoneal injection (i.p.), EO at 50 and 100 mg/kg significantly reduced the number of writhes (51.9 and 64.9%, respectively) and the number of paw licks during phase 2 (56.7 and 86.2%, respectively) of a formalin model when compared to control group animals. However, EO-treated mice were ineffective at all doses in hot-plate and rota-rod tests. The EO inhibited the carrageenan-induced leukocyte migration to the peritoneal cavity in a dose-dependent manner (34.7, 35.4, and 62.5% at doses of 25, 50 and 100 mg/kg, respectively). In the paw edema test, the EO (100 mg/kg) inhibited all three phases of the edema equally well, suggesting that the EO has a non-selective inhibitory effect on the release or actions of these mediators. Our results suggest possible antinociceptive and anti-inflammatory effects of the EO.