Cecropia pachystachya presented a more diverse chemical profile than C. hololeuca. The methodology developed herein could be an important tool to analyse commercial Cecropia (embaúba) products.

Ipomoea pes-caprae (Convolvulaceae), popularly known as “salsa-da-praia”, is used in folk medicine for the treatment of several diseases, including hypertension. The aim of this research was to evaluate hypotensive activity attributed to this species and identify the bioactive compounds responsible for this effect. Hydroalcoholic extract of aerial parts of Ipomoea pes-caprae (PIEA) was fractionated by column chromatography with Amberlite XAD-2, thus achieving a methanolic fraction (PIEA-M). The chemical profile investigation of PIEA-M was conducted by Ultra Performance Liquid Chromatography coupled to Mass Spectrometry (UPLC-MS) and compound isolation through High Performance Countercurrent Chromatography (HPCCC). Hemodynamic evaluations of PIEA, PIEA-M and isolated compounds were carried out on normotensive rats. The locomotor activity of PIEA and PIEA-M were performed by Rota Rod test using Swiss mice. UPLC-MS analysis of PIEA-M led to the identification of 11 compounds corresponding to seven phenolic acids and four flavonoids. By means of HPCCC, quercetin 6”-O-acetyl-3-O- glucoside (1), a mixture of quercetin-3-O-galactoside and quercetin-3-O- glucoside (2) and quercetin 3-O-glucoside (3) were isolated. PIEA, PIEA-M and the obtained compounds (1 and 2) significantly reduced blood pressure. Also, PIEA and PIEA-M caused significant impairment on mice locomotor activity. These results indicate the potential of Ipomoea pes-caprae as a source of hypotensive agents suggesting that phenolic compounds present in the species are responsible for its hypotensive activity.

Este trabalho tem por objetivo apresentar uma proposta didático-pedagógica desenvolvida com licenciandos em Química de um Instituto Federal, na qual foram utilizadas metodologias problematizadoras para a elaboração de sequências didáticas. A proposta foi desenvolvida durante o período de realização de uma disciplina denominada “Ambientes de Aprendizagem em Química II”. Nesta disciplina, os licenciandos foram incentivados a elaborar duas diferentes sequências didáticas, como proposta para aulas de Química de nível médio, embasadas em metodologias problematizadoras: o “Arco de Maguerez” e os “Três Momentos Pedagógicos”. Ao fim do processo, os licenciandos produziram relatos, analisados por meio da análise de texto discursiva. A partir da análise, constatou-se a necessidade de mudanças nas aulas de Química tradicionais e a viabilidade de utilização dessas metodologias problematizadoras para a preparação das aulas, as quais, por serem pautadas em problemas do cotidiano dos alunos, tornariam-se mais motivadoras e eficientes.

Background: The presence of phenolic compounds is common in Urticaceae. However, only one report of the isolation of an apigenin in the Pourouma genus is available. Pourouma guianensis occurs widely throughout Brazil, mainly in the Southeastern region, and is popularly known as “pitinga”. The chemical profile of P. guianensis is marked by the presence of steroids and triterpenes. Objective: This study carried out the characterization of phenolic substances using UPLC-DAD-MS separation, in order to increase the chemical knowledge on the Pourouma genus. Method: The extract was analyzed by UPLC-DAD-MS using a C-18 column, DAD detector at 190-400nm and ESI-Q-TOF mass spectrometer. The solvent system consisted of water with 0.1% formic acid (phase A) and acetonitrile with 0.1% formic acid (phase B). Results: The extract analysis identified the presence of ten compounds: two aryl propanoids (5-O-caffeoylquinic acid and 3-O-feruloylquinic acid) and eight glycosylated flavones derived from apigenin, luteonin and chrysoeryol (vicenin 2, saponarin, orientin, isoorientin, isoschaftoside, schaftoside, isovitexin and isoscoparin). Conclusion: The developed UPLC-DAD method was proven to be an efficient tool for the separation of phenolic mixtures and the UPLC-DAD-MS analysis enabled the identification of these compounds, reported for the first time in Pourouma genus.

Background: The Coussapoa genus (Urticaceae, tribe Cecropiae) contains 50 species mainly distributed throughout the Neotropical Region. Although some genera belonging to the Cecropiae tribe have been well-assessed, the chemical profile of Coussapoa members has not yet been investigated. Objective: In this context, the aim of the present study was to characterize phenolic substances present in a methanol extract obtained from Coussapoa microcarpa leaves employing UPLC-DAD-ESI-MS analyses Methods: Several condensed tannins (epi-afzelechin-epi-catechin, B-type and C-type procyanidins), flavan-3-ols ((+) -catechin and (-) - epicatechin), phenolic acid (O-caffeoylquinic acid) and C-glycosyl flavones (orientin, isoorientin, vitexin, isovitexin, isoorientin-2″-O-rhamnoside,vitexin-2″-O-hexoside, vitexin-2″-O-xyloside and isovitexin-2″-O-xyloside) were identified. Results: The determined chemical profile observed for C. microcarpa exhibits chemo-taxonomic significance compared to other neotropical genera. Conclusion: Structural variability of the identified secondary metabolites is of significant value for chemosystematic studies concerning the Coussapoa genus and the Cecropiae tribe, both still unexplored regarding their chemodiversity.