Protoflavanones from the Wood Stem of Salvertia convallariodora.

Phytochemical-analysis of the ethyl acetate extract of stem wood of Salvertia convallariodora A. St.-Hil. (Vochysiaceae), a Brazilian Cerrado species, led to the isolation and full characterization of three new non-aromatic B-ring flavanones (1-3) as well as the terpene mixture of sericic acid (4), 24-hydroxytormentic acid (5); 24-hydroxytormentic acid glucosyl ester (6), and sericoside (7), all identified for the first time from S. convallariodora. The structures of the new flavanones (1-3) were established from IR, LC-PDA-qTOF-MS, and NMR spectral data, including 2D NMR experiments.

Cytotoxic effect of Pouteria torta leaf extracts on human oral and breast carcinomas cell lines.

AIMS: This study aimed at investigating the cytotoxic activity and the type of cell death induced by Pouteria torta (P. torta) leaf extracts on human oral squamous cell carcinoma and breast carcinoma cell lines. MATERIAL AND METHODS: The effects of P. torta leaf hexanic (PTH), ethanolic (PTE) and aqueous (PTA) extracts at the concentration of 500 mg/mL were evaluated on OSCC-3 and MCF-7 cell lines, using crystal violet staining after 24 and 48 h of treatment. To obtain the dose-response curve, cells were treated with decreasing concentrations of the extracts (1000, 750, 500, 250, 125 mg/mL) for 24 h. To investigate the mechanism of cell death (apoptosis vs. necrosis), DNA fragmentation assay was performed. RESULTS: All extracts were cytotoxic to both OSCC-3 and MCF-7, albeit at differing levels. PTH and PTE were effective at the concentration of 500 µg/mL, resulting in nearly 50% of cell death in both cancer cell lines. PTA was more effective at lower concentrations, with more significant cell death at 125 g/mL. Treatment with PTA and PTE caused apoptosis in MCF-7, whereas in OSCC-3 cells, the same effect could only be caused by PTH. On the other hand, PTA was able to induce necrosis in OSCC-3. CONCLUSIONS: These findings demonstrated that P. torta leaf extracts may contain useful compounds to combat oral and breast cancer, and this study highlights the potential biological relevance of the Brazilian Cerrado Biome in cancer therapy.

Efeito de extratos de plantas do Cerrado em Dipetalogaster maxima (Uhler) (Hemiptera, Reduviidae) / Effect of Cerrado plant extracts on Dipetalogaster maxima (Uhler) (Hemiptera, Reduviidae)

A transmissão da doença de Chagas ocorre, principalmente, por meio de fezes de hemípteros hematófagos (Triatominae), os quais ingerem o Trypanosoma cruzi ao se alimentarem do sangue de pessoas ou outros mamíferos infectados. Para o controle dos triatomíneos, os piretróides são os principais inseticidas utilizados. Entretanto, algumas populações de insetos demonstraram resistência a determinados piretróides, indicando a necessidade do desenvolvimento de novos inseticidas eficazes no controle desses vetores. Assim, foi avaliada a atividade inseticida de 83 extratos vegetais, pertencentes a 35 espécies diferentes, em ninfas do primeiro estádio de Dipetalogaster maxima (Uhler, 1894) (Hemiptera: Reduviidae), triatomíneo encontrado no México. Para o teste tópico, foram aplicados 50 ìg de cada extrato nos tergitos abdominais de dez ninfas, em duplicata. Como controles, foram utilizados insetos tratados com etanol, acetona ou sem nenhum tipo de tratamento. Os triatomíneos foram observados durante 28 dias. Nenhum extrato apresentou atividade inseticida significativa, entretanto, o extrato hexânico do fruto e o etanólico da casca do caule de Simarouba versicolor (Simaroubaceae) inibiram a taxa de ecdise em D. maxima (40 por cento e 25 por cento, respectivamente). Sugere-se que estes extratos sejam quimicamente investigados e monitorados por ensaios biológicos a fim de determinar os componentes, para que estes possam ser utilizados como modelos moleculares ou como compostos biorracionais nos programas de controle de insetos.

Chagas disease, also known as American Trypanosomiasis, is chiefly transmitted by faeces of haematophagous bugs (Triatominae) that ingested Trypanosoma cruzi from blood of infected people or other mammals. Pyrethroids have been the main insecticides used against these insects. However, some populations of insects have shown significant levels of resistance to several pyrethroids, indicating the need of new insecticides for the control of triatomines. Thus, the insecticidal activity of 83 Cerrado plant extracts belonging to 35 species were assayed on first instar nymphs of Dipetalogaster maxima (Uhler, 1894) (Hemiptera, Reduviidae), species found in Mexico. For the extract application on triatomines, 50 μg of the extract were topically applied in duplicate on dorsal tergites of ten insects. Insects topically treated with acetone, ethanol, as well as insects with no treatment were used as controls. Triatomines were observed over a 28-day period. The extracts showed no insect mortality, however, fruit hexane and stem bark ethanolic extracts of Simarouba versicolor (Simaroubaceae) inhibited the rate of ecdysis in D. maxima (40 percent and 25 percent, respectively). These preliminary data suggest that this extracts should be chemically investigated and monitored through biological assays in order to determine the components, so that it may be used as a molecular model or as biorational compounds for use in insect control programmes.

Insecticidal activity of cerrado plant extracts on Rhodnius milesi Carcavallo, Rocha, Galvão & Jurberg (Hemiptera: Reduviidae), under laboratory conditions.

Chagas' disease is chiefly transmitted by feces of haematophagous bugs (Triatominae) that ingested Trypanosoma cruzi from blood of infected people or animals. Pyrethroids have been the main insecticides used against these insects. However, some populations of insects have shown significant levels of resistance to several pyrethroids, indicating the need of new insecticides for the control of triatomines. Insecticidal activity of 24 Cerrado plant extracts belonging to five species of four families were assayed on fourth instar nymphs of Rhodnius milesi Carcavallo, Rocha, Galvão & Jurberg (Hemiptera: Reduviidae), under laboratory conditions. For the extract application on triatomines, 50 microg of the extract were topically applied in duplicate on dorsal tergites of ten insects. Insects topically treated with acetone, ethanol, as well as insects with no treatment were used as controls. Triatomines were observed over a 28-day period. Hexanic and ethanolic extracts of Simarouba versicolor, Guarea kunthiana, Guarea guidonia and Talauma ovata caused mortality between 20% and 95% of R. milesi in comparison with the controls, which showed no insect mortality. These preliminary data suggest that the ethanolic extract of the root bark of S. versicolor and the hexanic extract of the root of G. guidonia, responsible for a 95% and 75% insect mortality, respectively, should be chemically investigated and monitored through biological assays in order to determine their insecticidal components, that could be used as a molecular model or as biorational compounds for use in insect control programmes.