Methanolic, diethyl ether and n-hexane extracts of leaves of four species of Senna (S. gardneri, S. macranthera, S. splendida and S. trachypus) were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). Using linear retention indices and mass spectral data, 34 compounds were identified, including fatty acids, flavonoids, terpenoids and steroids that were not reported previously for these species. Additionally, the cytotoxicity of the extracts against different tumor cell lines was determined. The cytotoxicity was then correlated with the chemical composition of the extracts by partial least squares-discriminant analysis (PLS-DA). The n-hexane extract of S. gardneri and the ethyl ether extract of S. splendida were the most active against human colon (59.75 and 31.37%, respectively) and human glioblastoma (52.85 and 48.28%, respectively) cell lines.

A investigação fitoquímica do extrato etanólico do caule de Senna martiana Benth. (Leguminoseae), espécie nativa do nordeste do Brasil, permitiu o isolamento e caracterização espectroscópica de uma biantrona inédita denominada martianina (1), 10,10'-H-bicrisofanol10-ox-10,10'-biglucosil. Sua identificação estrutural inequívoca foi estabelecida por HRMS, IV e RMN de ¹H e 13C uni e bi-dimensional. A atividade tripanocida de martianina foi avaliada por seu comportamento frente à enzima GAPDH Tc através da obtenção de sua constante de inibição (Ki) determinada por titulação calorimétrica isotérmica (27,3 ± 2,47 µmol L-1). Estes resultados sugerem que esta classe de molécula tem potencial no desenvolvimento de novos fármacos a serem utilizados contra a doença de Chagas.

A phytochemical investigation of the ethanolic extract of stalks of Senna martiana Benth. (Leguminoseae), native specie of northeast Brazil, resulted in the isolation and spectroscopic characterization of a new bianthrone glycoside, martianine 1 (10,10'-il-chrysophanol-10-oxi10,10'-bi-glucosyl). Its identification was established by HRMS, IR and 2D NMR experiments. The evaluation of martianine trypanocidal activity was carried out against gliceraldehyde 3-phosphate dehydrogenase enzyme from Trypanosoma cruzi. Its inhibitory constant (Ki) is in the low micromolar concentration and it was determined by isothermal titration calorimetry to be 27.3 ± 2.47 µmol L-1. The non-competitive mechanism is asserted to be putative of the mode of action martianine displays against T. cruzi GAPDH. Results show that martianine has a great potential to become new lead molecule by inhibiting this key enzyme and for the development of new drugs against Chagas disease.