Toxic plants from the perspective of a "Quilombola" community in the Cerrado region of Brazil.

A multi-disciplinary team surveyed ranchers at the Kalunga Historical and Cultural Heritage Site, in the Cerrado region of west central Brazil, to determine impacts promoted by toxic plants on cattle. The expedition to the Kalunga region was carried out by Brazilian and American researchers. Previously selected cattle ranch properties from "Vão das Almas", "Engenho II" and "Vão do Moleque" were visited. Twenty-four interviews were carried out with cattle ranchers and a questionnaire was applied to obtain information about outbreaks of native plant poisoning and their effects on livestock, and the use of local plants in phytotherapy. We classified problematic plants into three distinct categories. First, the toxic plants most cited by residents causing cattle losses were the flowers of Caryocar brasiliense Cambess ("pequi"), the fruits of Terminalia corrugata (Ducke) Gere & Boatwr. (Buchenavia tomentosa Eichler - "mirindiba" or "pau-pilão"), Eugenia dysenterica (Mart.) DC ("cagaita"), and Palicourea marcgravii A. St. Hil ("erva-café" or "cafezinho"). Secondly, other plants considered toxic, but causing less severe losses were Emmotum nitens (Benth.) Miers ("casco d'anta"), Indigofera lespedezioides (Kunth) ("timbozinho"), Ricinus communis L. ("mamona"), Pteridium esculentum (G. Forst.) Cockayne ("samambaia"), Stryphnodendron adstringens (Mart.) Coville ("barbatimão"), and Actinocladum verticillatum (Nees) McClure ex Soderstr. ("cambaúba"). The most important finding was the identification of the C. brasiliense flower as potentially toxic to cattle, which must be subject for future research. Further, we confirmed the toxicity and importance of P. marcgravii, E. dysenterica, and Terminalia corrugata. The survey highlighted phytotherapy plants used by the community, and greatly increased awareness by local livestock producers of poisonous plants for management purposes. We conclude that ethnobotanical knowledge, especially from the traditional community, is essential to understand livestock losses to toxic plants, and should be valued not only for reducing livestock losses, but also for cultural importance to the Kalunga communities in the Cerrado.

Chemovariations in Hypenia essential oils under infrageneric and phenological influences.

The essential oils (EOs) of six Hypenia species that are endemic in the central Brazilian Cerrado were assessed by GC/MS and chemometric analysis. EO variations according to two taxonomic sections, combined with two phenophases (vegetative and reproductive), showed that 23.2% of total variance was explained by such predictors. Variation partitioning showed that the largest pure contribution was attributed to section (43.7%), followed by phenophase (39.3%), with 17% of joint influence. A multivariate regression tree (MRT) indicated that 13 EO constituents may be potential chemomarkers for distinguishing sections and two developmental stages in the genus.

Assessment of genotoxicity and cytotoxicity of "lixeira" (Curatella americanaL. ) using the prophage λ induction test (SOS inductest) / Avaliação da genotoxicidade e citotoxicidade de "lixeira" (Curatella americana L.) utilizando o teste de indução profago λ (teste de indução SOS)

Curatella americana L., commonly known as "lixeira" in Brazil, has been used in folk medicine to treat ulcers and inflammations. The purpose of the present work was to evaluate the cytotoxic and genotoxic potential of the ethanolic extract of C. americana stem bark using the prophage λ induction test (SOS inductest). To evaluate the cytotoxicity of this plant, after treatment with different concentrations of the extract, Escherichia coli WP2s(λ) cultures were diluted in M9 buffer, inoculated into LB plates, and incubated for 24 h at 37 ºC. To assess genotoxicity, the lysogenic strain E. coli WP2s(λ) was treated with different concentrations of the extract. Then, the lysogenic strain was added to the indicator strain (RJF013), LB(1/2)(malt/amp), seeded into plates with the matches, and incubated for 24 h at 37 ºC. After this period, the total number of colonies and the number of plaques were counted to evaluate C. americana cytotoxicity and genotoxicity, respectively. Our results showed that although the extract of "lixeira" did not modify the survival of bacteria (p > 0.05), it caused a significant increase in prophage λ induction, especially at the higher concentrations (p<0.05). Therefore, we conclude that the ethanolic extract of C. americana stem bark did not present cytotoxic effect, but some genotoxic potential was observed.

Curatella americana L., comumente conhecida como "lixeira" no Brasil, é utilizada em medicina popular para tratamento de úlceras e inflamações. O presente trabalho teve como objetivo avaliar o potencial citotóxico e genotóxico do extrato etanólico das cascas de C. americana utilizando o Induteste SOS. Para avaliar a citotoxicidade da planta, depois de tratadas com diferentes concentrações do extrato, culturas de E. coli WP2s(λ) foram diluνdas em tampão M9 e semeadas em placas LB. Para avaliar a genotoxicidade da planta, a cepa lisogênica WP2s(λ) de E. coli foi tratada com diferentes concentrações do extrato. Em seguida, esta foi adicionada à cepa indicadora (RJF013) e ambas foram semeadas em placas em meio LB(1/2)(malt)(amp). Todas as culturas foram incubadas por 24 h a 37 ºC. Posteriormente, o número total de colônias e o número de centros infecciosos foram computados para a avaliação da citotoxidade e da genotoxicidade desta planta, respectivamente. Os resultados mostraram que embora o extrato de C. americana não tenha modificado a sobrevivência bacteriana (p > 0,05), provocou aumento significativo (p < 0,05) na indução do profago λ, especialmente nas concentrações mais altas. Assim, concluiu-se que o extrato etanólico das cascas de C. americana não apresentou atividade citotóxica, mas foi observada ação genotóxica direta.