Antiproliferative activity, antioxidant capacity and chemical composition of extracts from the leaves and stem of Chresta sphaerocephala

AbstractIn this study, antiproliferative and antioxidant activities of crude extracts (hexane, ethyl acetate and methanol) from leaves and stem of Chresta sphaerocephala DC., Asteraceae, were investigated. Antiproliferative activity was tested in vitro against ten human cancer cells and against VERO (no cancer cell). Antioxidant activities were determined using DPPH and ORAC-FL assays and the total phenolic content was estimated by Folin–Ciocalteu method. Hexane and ethyl acetate extracts (leaves and stem) exhibited antiproliferative activity against cancer cell lines with total growth inhibition (TGI) between 50.40 and 250 µg/ml. For VERO cell, TGI values were >250 µg/ml for all extracts, except to hexane extract of the stem (TGI 80.92 µg/ml). In an initial evaluation, ethyl acetate and methanol extracts (leaves and stem) have shown levels of phenolic compounds between 6.94 and 30.96 mg GAE/kg in Folin–Ciocalteu assay, DPPH free-radical scavenging activity with SC50 in the range of 75.22 and 400 µg/ml and antioxidant capacity between 290.08 and 1088 µmol TE/g of extract in ORAC-FL assay. HPLC-DAD and ESI-MS analysis allowed the identification of flavonoids in the methanol extract from the leaves of C. sphaerocephala. Three steroids and nine triterpenoids were identified in the bioactive hexane extracts using HRGC.

Analysis of the hepatoprotective activity and the toxicological, chemical and physical-chemical profiles of a sample of Brazilian propolis

In the present assay, the hepatoprotective activity of a sample of propolis from Rio Azul (PR) BRazil was studied using the model of acute hepatotoxicity induced by carbon tetrachloride (CCl4). The physical-chemical, chemical and toxicological profiles of the sample were also studied. The chemical analyses of the sample indicated the presence of gallic acid derivatives, 3-methoxy-4-hydroxy cinnamaldehyde as well as other unidentified compounds....

Análise química, toxicológica e antiulcerogênica preliminar de uma amostra de própolis da região do Paraná / Preliminary chemical, toxicological and anti-ulcerogenic analysis o of sample of propolis from the region of Paraná

O presente trabalho investigou a constituição química e as propriedades toxicológicas e farmacológicas de uma amostra de própolis oriunda da região de Rio Azul (PR), Brasil. As análises químicas foram realizadas por cromatografia líquida de alta resolução acompanhadas do estudo físico-químico da velocidade de oxidação por permanganato de potássio. O ensaio toxicológico consistiu na determinação da toxicidade aguda em dose simples, dose letal mediana (DL50) e Screening Hipocrático em camundongos, pela administração per os da amostra. A análise da atividade antiulcerogênica foi conduzida em protocolo de úlcera induzida pela administração subcutânia de indometacina a ratos albinos. Os resultados das análises químicas indentificaram alguns compostos derivados do ácido e o 3-metoxi-4-hidroxicinamaldeído, bem como outros ainda não indentificados.Do ponto de vista toxicológico a amostra pesquisada não evidenciou efeitos deletérios sobre a função do sistema nervoso central, autônomo e atividade motora, revelando valor de DL50 superior a 5000mg.kg 1. A dose de 1,0 g.kg1 de própolis foi competente em reduzir o índice médio das lesões ulcerativas em 72,06 por cento nas unidades experimentais tratadas com a indometacina, evidenciando significante atividade antiulcerogênica.