RESUMO
ABSTRACT The essential oil from Croton polyandrus Spreng., Euphorbiaceae, leaves was tested for the toxicity and antitumor activity. The concentration producing 50% hemolysis was 141 µg/ml on mice erythrocytes. In the acute toxicological study, the estimated LD50 was 447.18 mg/kg. The essential oil did not induce increase in number of micronucleated erythrocytes, suggesting low genotoxicity. Essential oil (100 or 150 mg/kg) showed significant antitumor activity in Ehrlich ascitic carcinoma model. We observed that essential oil induces cell-cycle arrest at the G0/G1 phase, and increases the sub-G1 peak, which represents a marker of cell death by apoptosis. Survival also increased for the treated animals. The toxicological analyses revealed reduction in body weight, increased aspartate aminotransferase and alanine aminotransferase activity, hematological changes, and a thymus index reduction. These data suggest gastrointestinal and liver toxicity, anemia, leukopenia/lymphocytopenia, and immunosuppressive effects. Histopathological analysis revealed the weak hepatotoxicity of essential oil. In summary, essential oil of C. polyandrus displays in vivo antitumor activity and moderate toxicity.
RESUMO
The flavonoids are a large class of polyphenolic compounds found in plants that are known to exhibit biological effects. In the study, the flavonoid 5.7.4-trimethoxyflavone (TMF) extracted from Praxelis clematidea was evaluated for its antibacterial activity. Microdilution method was used for antibacterial assay of the flavonoid and eleven bacteria strains were used in the study for activities. The results were also compared with the standard drug, Chloramphenicol (100 ug/mL). The results obtained showed activity of the flavonoid against Gram positive and Gram negative bacteria.
Los flavonoides son una clase importante de compuestos polifenólicos encontrados en las plantas que se sabe que presentan efectos biológicos. En el estudio, el flavonoide 5.7.4 '-trimethoxyflavone (TMF) extraído de Praxelis clematidea fue evaluado por su actividad antibacteriana. Se utilizó el método de microdilución para el ensayo antibacteriano del flavonoide y once cepas de bacterias se usaron en el estudio de las actividades. Los resultados se compararon también con el fármaco estándar, Cloranfenicol (100 ug/mL). Los resultados obtenidos mostraron actividad del flavonoide contra bacterias Gram positivas y Gram negativas.