Evaluation of antiulcer activity of the main phenolic acids found in Brazilian Green Propolis

Gastric antiulcer and anti-inflammatory activities of the essential oil from Casearia sylvestris Sw.

Plants popularly used for loosing weight purposes in Porto Alegre, South Brazil

The crude aqueous extract from the leaves of Casearia sylvestris, a plant found in Brazilian open pastures, was assayed for its ability to inhibit phospholipase A2 (PLA2) activity and some biological activities of bee and several snake venoms, and of a number of isolated PLA2s. The extract induced partial inhibition of the PLA2 activity of venoms containing class I, II and III PLA2s. When tested against the purified toxins, it showed the highest efficacy against class II PLA2s from viperid venoms, being relatively ineffective against the class I PLA2 pseudexin. In addition, C. sylvestris extract significantly inhibited the myotoxic activity of four Bothrops crude venoms and nine purified myotoxic PLA2s, including Lys-49 and Asp-49 variants. The extract was able to inhibit the anticoagulant activity of several isolated PLA2s, with the exception of pseudexin. Moreover, it partially reduced the edema-inducing activity of B. moojeni and B. jararacussu venoms, as well as of myotoxins MjTX-II and BthTX-I. The extract also prolonged the survival time of mice injected with lethal doses of several snake venoms and neutralized the lethal effect induced by several purified PLA2 myotoxins. It is concluded that C. sylvestris constitutes a rich source of PLA2 inhibitors.

Effects of aqueous extract of Casearia sylvestris (Flacourtiaceae) on actions of snake and bee venoms and on activity of phospholipases A2.

RESUMO Este estudo avaliou as atividades antimicrobianas (AA) de extratos hidro-alcoolicos, obtidos de 17 especies de arvores nativas do Brasil. Para os ensaios de antibiose foi utilizado o metodo da difusao em agar, frente a 10 diferentes microrganismos, isolados de inoculos obtidos de focos de infeccoes clinicas. Dos 170 testes realizados, 25% mostraram alta AA, destacando-se extratos de Bixa orellana, Psidium guajava e Anacardium occidentale. Excepcional AA foi observada em Mimosa tenuiflora contra Streptococcus pyogenes, Proteus mirabilis, Shigella sonnei, Staphylococcus aureus e Staphylococcus spp. coagulase-negativa, e os extratos de Stryphnodendron adstringens e Eugenia uniflora contra Escherichia coli, Providencia spp., Streptococcus pyogenes, Proteus mirabilis, Shigella sonnei, Staphylococcus aureus e Staphylococcus spp. coagulase-negativa. Ensaios de antibiose com antibioticos comerciais foram realizados contra estas bacterias, com a finalidade de se comparar o potencial de AA de extratos destas arvores. PALAVRAS-CHAVE: Atividade antimicrobiana, plantas medicinais, antibiose.

C.A. Azzolini

Papers

Pharmacological assay of Casearia sylvestris. I: Preventive anti-ulcer activity and toxicity of the leaf crude extract.