Background: Eugenia species are appreciated for their edible fruits and are known as having anticonvulsant, antimicrobial and insecticidal actions. Methods: The plant material was collected in the southeastern Pará state of Brazil and submitted to hydrodistillation. GC-MS analyzed the oils, and their antioxidant and cytotoxic activities were evaluated by the DPPH and MTT assays. Results: The main components identified in the Eugenia oils were 5-hydroxy-cis-calemene, (2E,6E)-farnesol, (2E,6Z)-farnesol, caryophylla-4(12),8(13)-dien-5α-ol-5β-ol, E-γ-bisabolene, β-bisabolene, germacrene D, and ishwarane. The oil of E. egensis showed the most significant antioxidant activity (216.5 ± 11.6 mg TE/mL), followed by the oils of E. flavescens (122.6 ± 6.8 mg TE/mL) and E. patrisii (111.2 ± 12.4 mg TE/mL). Eugenia oils were cytotoxic to HCT-116 (colon cancer) cells by the MTT assay, where the most active was the oil of E. polystachya (10.3 µg/mL), followed by the oils of E. flavescens (13.9 µg/mL) and E. patrisii (16.4 µg/mL). The oils of E. flavescens and E. patrisii showed the highest toxicity for MRC5 (human fibroblast) cells, with values of 14.0 µg/mL and 18.1 µg/mL, respectively. Conclusions: These results suggest that Eugenia oils could be tested in future studies for the treatment of colon cancer and oxidative stress management.

No abstract

The essential oils of leaves and twigs from the Euphorbiaceous Croton draconoides, C. urucurana and Julocroton triqueter were obtained and analyzed by GC and GC-MS. In total, 101 volatile constituents were identified, comprising an average of 90% of the oil, mostly made up of mono-and sesquiterpenes. The monoterpene hydrocarbons varied from 1.2 to 40.2%, the sesquiterpene hydrocarbons from 34.0 to 49.6% and the oxygenated sesquiterpenes from 11.5 to 51.3%. The main compounds found in the oil of C. draconoides were β-pinene (16.9%), α-pinene (16.5%), curzerene (12.8%), germacrene D (9.0%), γ-elemene (4.7%), and elemol (4.4%). The oil of C. urucurana showed sesquicineole (23.0%), dehydro-sesquicineole (13.8%), β-caryophyllene (7.9%), β-bisabolol (5.0%), germacrene D (4.2%) and β-elemene (4.1%) as the chief compounds. The oil of J. triqueter was dominated by β-caryophyllene (16.3%), β-phellandrene (10.2%), spathulenol (5.1%), caryophyllene oxide (5.0%), δ-cadinene (4.3%), (E)-nerolidol (4.3%), and α-copaene (4.1%).

Seed oil (Pp-oil) of Plukenetia polyadenia is used by native people of the Brazilian Amazon against arthritis and rheumatism, spreading it on the arms and legs to reduce the pain and inflammation. Pp-oil was obtained by pressing dried seeds at room temperature to give a 47.0% yield of oil. It was then subjected to fatty acid composition analysis. The principal fatty acids were linoleic acid (46.5%), α-linolenic acid (34.4%) and oleic acid (13.9%). Then, it was evaluated for its antinociceptive activity in mice, using the acetic acid-induced abdominal writhing, hot plate and formalin test models. Additionally, OPEN ACCESSMolecules 2015, 20 7926 its toxicity was determined. The Pp-oil proved to have no toxicological effects, showing dose-dependent antinociceptive effect under chemical stimulation. At oral doses of 25-100 mg/kg, Pp-oil significantly reduced the abdominal writhes in the writhing test. A higher oral dose of 200 mg/kg did not induce alterations in the latency time of the hot plate test when compared to the control, suggesting an analgesic activity of peripheral origin. At oral doses of 50 and 100 mg/kg, the Pp-oil significantly reduced the second phase of the algic stimulus in the formalin test. In addition, the antinociception of Pp-oil was reversed by naloxone in the evaluation of its mechanism of action. Therefore, the Pp-oil proved to be safe at very high doses and to show significant analgesic properties. The role of Pp-oil is still being investigated with respect the mechanism of action, but the results suggest that opiod receptors could be involved in the antinociception action observed for the oil of P. polyadenia.

No abstract

Na busca por metodologias para melhor atender à formação de estudantes do Ensino Superior da Química, uma das abordagens pedagógicas mais promissoras atualmente é ABP. O objetivo geral deste trabalho foi planejar, implantar e avaliar a abordagem ABP utilizando o Google Sala de Aula em uma turma de Ensino Superior. A maioria dos participantes relataram que se sentiram mais motivados e que o rodízio entre os perfis na ABP produziu trabalho em equipe mais colaborativo. Concluímos que uma abordagem diferente para o ensino superior e uma melhor utilização das tecnologias educacionais podem ajudar professores a aumentar a sua eficácia com um corpo discente diversificado.

In this study, the oil constituents of Lippia gracilis were identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antioxidant and antifungal activities were also evaluated. The leaf oil showed a yield of 3.7% and its main constituents were thymol (70.3%), p-cymene (9.2%), thymol methyl ether (5.4%) and p-methoxythymol (2.7%). The thin stem oil showed a yield of 0.4% and its major components were thymol (70.1%), thymol methyl ether (4.4%), p-methoxythymol (4.0%), p-cymene (3.8%), α-humulene (2.4%) and (E)-caryophyllene (2.1%). The aromatic monoterpenes found in the oils showed an average of 88%. The scavenging activity of the 1,1-diphenyl-2picrylhydrazyl radical (DPPH) for the leaf oil, expressed as half maximal effective concentration (EC 50 ), was 35.7±3.3 µg/ml, indicating high antioxidant activity. The evaluation of fungicide activity for the leaf oil, using direct bioautography, showed also a significant value for lethal concentration (LC 50 5.0 μg/ml) against Cladosporium sphaerospermum and C. cladosporioides fungi.

No abstract