The main challenge of plant chemical diversity exploration is how to develop tools to study exhaustively plant tissues. Their sustainable sourcing is a limitation as bioguided strategies and dereplication need quite large amounts of plant material. We examine if alternative solutions could overcome these difficulties by obtaining a secure, sustainable, and scalable source of tissues able to biosynthesize an array of metabolites. As this approach would be as independent of the botanical origin as possible, we chose eight plant species from different families. We applied a four steps culture establishment procedure, monitoring targeted compounds through mass spectrometry-based analytical methods. We also characterized the capacities of leaf explants in culture to produce diverse secondary metabolites. In vitro cultures were successfully established for six species with leaf explants still producing a diversity of compounds after the culture establishment procedure. Furthermore, explants from leaves of axenic plantlets were also analyzed. The detection of marker compounds was confirmed after six days in culture for all tested species. Our results show that the first stage of this approach aiming at easing exploration of plant chemodiversity was completed, and leaf tissues could offer an interesting alternative providing a constant source of natural compounds.

Margaritaria nobilis is a shrubby species widely distributed in Brazil from the Amazon to the Atlantic Rainforest. Its bark and fruit are used in the Peruvian Amazon for disinfecting abscesses and as a tonic in pregnancy, respectively, and its leaves are used to treat cancer symptoms. From analyses via UHPLC-MS/MS, we sought to determine the chemical profile of the ethanolic extract of M. nobilis leaves by means of putative analyses supported by computational tools and spectral libraries. Thus, it was possible to annotate 44 compounds, of which 12 are phenolic acid derivatives, 16 are O-glycosylated flavonoids and 16 hydrolysable tannins. Among the flavonoids, although they are known, except for kaempferol, which has already been isolated from this species, the other flavonoids (10, 14, 15, 21, 24–26, 28–30, 33–35, 40 and 41) are being reported for the first time in the genus. Among the hydrolysable tannins, six ellagitannins present the HHDP group (6, 19, 22, 31, 38 and 43), one presents the DHHDP group (5), and four contain oxidatively modified congeners (12, 20, 37 and 39). Through the annotation of these compounds, we hope to contribute to the improved chemosystematics knowledge of the genus. Furthermore, supported by a metric review of the literature, we observed that many of the compounds reported here are congeners of authentically bioactive compounds. Thus, we believe that this work may help in understanding future pharmacological activities.

Este estudo descreve a aplicação e análise de uma aula problematizadora sobre a utilização e descarte inadequado de pilhas e baterias, tendo o objetivo de estimular a sensibilização ambiental em alunos do 9° ano de uma escola municipal de ensino público. Nesse sentido, a intervenção didática seguiu as seguintes etapas problematizadoras: (i) primeiramente, fez-se a investigação dos conhecimentos prévios dos discentes por meio da aplicação de um questionário; (ii) em seguida, desenvolveu-se uma aula expositivo-dialogada abordando características elementares envolvidas na temática proposta; (iii) depois, propôs-se uma pesquisa extraclasse envolvendo aspectos sustentáveis da utilização de pilhas e baterias e, por fim, (iv) seguiu-se de debates sobre os resultados apontados. Como resultado, constatou-se que os conhecimentos prévios dos alunos demonstraram pouca sapiência sobre o descarte desses resíduos e base conceitual acerca do assunto. Contudo, após a abordagem dialógica-problematizadora, percebeu-se o interesse dos alunos na temática a partir de evidenciações marcadas em seu dia a dia. As pesquisas extraclasse, por sua vez, demonstraram a percepção das consequências ambientais em detrimento do descarte inadvertido desses resíduos, levando a propostas de logísticas reversa, aplicação de multas à infratores, dentre outras. Com base isso, fez-se uma comparação dos novos conhecimentos apresentados, onde percebeu-se que o descaso apriorístico, por parte dos alunos, reverteu-se em um comprometimento na adoção de atitudes sustentáveis. Assim, considera-se que esta vertente estratégica atingiu o alcance de subsidiar uma aprendizagem suficiente para desenvolver a sensibilização ambiental sobre o uso e descarte corretos desses resíduos sólidos.

Margaritaria nobilis L.f. (Phyllanthaceae), a native Brazilian tree occurring mainly in the Amazon, is used in folk medicine for the treatment of abscesses (bark) and cancer-like symptoms (leaves). The present study evaluates the safety of its acute oral administration and its effects on nociception and plasma leakage. The chemical constitution of the leaf’s ethanolic extract is determined by ultra-performance liquid chromatography–high-resolution mass spectrometry (LC-MS. Its acute oral toxicity is evaluated in female rats at a dose of 2000 mg/kg, evaluating the occurrence of deaths and Hippocratic, behavioral, hematological, biochemical, and histopathological changes, as well as food and water consumption and weight gain. Antinociceptive activity is evaluated in male mice with acetic-acid-induced peritonitis (APT) and formalin (FT) tests. An open field (OF) test is performed to verify possible interferences in the animals’ consciousness or locomotion. LC-MS analysis shows the presence of 44 compounds classified as phenolic acid derivatives, flavonoids and O-glycosylated derivatives, and hydrolyzable tannins. No deaths or significant behavioral, histological, or biochemical changes are observed in the toxicity assessment. In nociception tests, M. nobilis extract significantly reduces abdominal contortions in APT, demonstrating selectivity for inflammatory components (FT second phase), not interfering in neuropathic components (FT first phase) or consciousness and locomotion levels in OF. Additionally, M. nobilis extract inhibits plasma acetic-acid-induced leakage. These data demonstrate the low toxicity of M. nobilis ethanolic extract, as well as its effectiveness in modulating inflammatory nociception and plasma leakage, possibly related to the flavonoids and tannins present in its composition.

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