Cytotoxic activity of the sub-fraction 2125 from Vernonia scorpioides against Sarcoma 180 tumor cells in mice

The effect of the selected sub-fraction SF-2125 of the Vernonia scorpioides leaf extract on Sarcoma 180 (S180) ascitic tumor-bearing mice was investigated. The animals were treated with SF-2125 at a concentration of 5 mg/kg, administered intraperitoneally and intravenous during the development of the tumor. Treatment with SF-2125 5 mg/kg i.p. increased the lifespan of the animals, maintained their body and the ascitic tumor showed no development. Intravenous treatment did not reduce the tumor volume

Search for antimicrobial activity among fifty-two natural and synthetic compounds identifies anthraquinone and polyacetylene classes that inhibit Mycobacterium tuberculosis

Drug-resistant tuberculosis threatens to undermine global control programs by limiting treatment options. New antimicrobial drugs are required, derived from new chemical classes. Natural products offer extensive chemical diversity and inspiration for synthetic chemistry. Here, we isolate, synthesize and test a library of 52 natural and synthetic compounds for activity against Mycobacterium tuberculosis. We identify seven compounds as antimycobacterial, including the natural products isobavachalcone and isoneorautenol, and a synthetic chromene. The plant-derived secondary metabolite damnacanthal was the most active compound with the lowest minimum inhibitory concentration of 13.07 μg/mL and a favorable selectivity index value. Three synthetic polyacetylene compounds demonstrated antimycobacterial activity, with the lowest MIC of 17.88 μg/mL. These results suggest new avenues for drug discovery, expanding antimicrobial compound chemistries to novel anthraquinone and polyacetylene scaffolds in the search for new drugs to treat drug-resistant bacterial diseases

Sesquiterpene lactones from Hedyosmum brasiliense induce in vitro relaxation of rat aorta and corpus cavernosum

Abstract Hedyosmum brasiliense Miq., Chloranthaceae, has been used in Southern Brazil as a sedative, anti-inflammatory, and aphrodisiac. In this study, endothelium-intact and endothelium-denuded rat aortic rings and strips of corpus cavernosum were used to investigate the relaxant effects of an hexane fraction of leaves of H. brasiliense and its sesquiterpene lactones 13-hydroxy-8,9-dehydroshizukanolide, podoandin, and elemanolide 15-acetoxy-isogermafurenolide. The incubation of hexane fraction of leaves of H. brasiliense resulted in significant relaxation of endothelium-intact aortic rings previously contracted by phenylephrine. In addition, 13-hydroxy-8,9-dehydroshizukanolide and podoandin displayed a clear concentration-dependent ability to relax endothelium-intact (∼85 to 90%) and endothelium-denuded (∼45 to 55%) rat aortic rings. A less pronounced vascular relaxation was recorded when 15-hydroxy-isogermafurenolide was tested. Interestingly, in tissues previously incubated with the nitric oxide synthase inhibitor L-NAME (100 µM), both 13-hydroxy-8,9-dehydroshizukanolide and podoandin had their effects in endothelium-intact vessels reduced to the same degree of relaxation observed in endothelium-denuded aortic rings. Podoandin, 13-hydroxy-8,9-dehydroshizukanolide, and 15-acetoxy-isogermafurenolide (100 µM) were also able to relax precontracted corpus cavernosum strips by 49.5 ± 3.9%, 65.9 ± 7.3% and 57.9 ± 5.5%, respectively. Our results demonstrated that 13-hydroxy-8,9-dehydroshizukanolide, podoandin and 15-acetoxy-isogermafurenolide, isolated from H. brasiliense, generate both endothelium-dependent and -independent relaxation of rat aortic rings, as well as being able to induce in vitro relaxation of rat corpus cavernosum. Importantly, the endothelium-dependent effect is fully dependent on nitric oxide production. Considering that penile erection depends on both relaxation of cavernosal smooth muscle and inflow of blood for the cavernous bodies, this is the first study reporting experimental evidence supporting the aphrodisiac properties of H. brasiliense

Análise de óleos-resinas de copaiba:contribuição para o seu controle de qualidade

A óleo-resina de copaíba pode ser extraída de forma sustentável do tronco de várias espécies de Copaifera. Ela contém principalmente ácidos resinosos e substâncias voláteis, tendo ampla utilização medicinal. A padronização cromatográfica do óleo é a garantia da identidade desta matéria-prima complexa. Neste trabalho analisaram-se por CG três amostras de óleos de copaíba obtidas de Colombo/PR e doze amostras adquiridas no Estado do Amazonas. O óleo de copaiba foi fracionado por cromatografia em sílica gel impregnada com KOH e metilado e as frações obtidas foram avaliadas por CG. Numa segunda etapa, os óleos brutos metilados por meio de diazometano ou transesterificados com KOH/MeOH foram injetados diretamente em CG. Foram utilizados para comparação os ácidos diterpênicos hardwíckiico, copaiferólico e caurenóico além do sesquiterpeno 14-hidroxi-b-cariofileno (cariofilenol). A presença do ácido copaiferólico foi observada em 100% e cariofilenol em 80% das amostras. Os ácidos caurenóico e hardwíckiico ausentes nas amostras do Paraná, foram detectados em 8,3% e 41,7% respectivamente nas amostras do Amazonas. Os resultados obtidos indicam que podem ser analisados diretamente através de CG após metilação com diazometano, sem necessidade de fracionamento prévio. Adicionalmente, a determinação do índice de acidez para óleos de copaíba não demonstrou resultados inequívocos para as amostras analisadas