Seventeen sesquiterpene lactones (SLs) isolated from five species of the tribe Vernonieae were evaluated for their in vitro activity against promastigotes of Leishmania amazonensis and Leishmania braziliensis. Additionally, a quantitative structure activity relationship has been made, since all these natural compounds were found to have potent to mild antileishmanial properties. The most active compounds against L. braziliensis were 16 and 17 (IC values 1.45 and 1.34 μM, respectively), followed by compound 15 with IC value of 1.60 μM against L. amazonensis. The three glaucolide-type SLs (4-6) were the least active against both parasites. The computational study allowed us to establish that lipophilicity and polarisability play an important role in the antiparasitic activity. This is the first report of the known germacradiendiolides 16 and 17 from Elephantopus mollis. The activity data of the compounds 1-17 assayed against Leishmania parasites are reported here for the first time.

Propolis is used in Bolivia as an antimicrobial agent. Bolivian propolis from the main production areas was assessed for antibacterial and leishmanicidal effect and the results were compared with the propolis chemical composition. The active antibacterial propolis samples were phenolic-rich while those containing mainly triterpenes were devoid of activity or weakly active. A similar picture was obtained for the effect on Leishmania, with better effect for the phenolic-rich samples. As propolis is used for the same purposes regardless of the production area and composition, our findings indicate the need for the standardization of this natural product as antimicrobial.

Parasitoses are very common throughout the world, generating serious consequences for public health. Leishmaniosis and giardiasis are examples of fairly recurrent, but neglected diseases. Several higher plants have demonstrated promising activity against the parasites. The aim of this study was to evaluate the biological activity of extracts, fractions and isolated compounds from the leaves and stems of two Brazilian plants: Eugenia mattosii and Marlierea eugeniopsoides (Myrtaceae) against Leishmania and Giardia. XTT and the fluorimetric method were used to for this evaluation, respectively. Cytotoxicity was evaluated against HeLa cells. The results demonstrated that chloroform fractions of E. matosii and pinostrobin presented the most pronounced antiparasitic activity, with the CLF-stems being the most effective against Leishmania amazonensis and Leishmania braziliensis. Pinostrobin also presented activity against G. lamblia. Therefore, E. mattosii stems and pinostrobin may be considered possible targets for the continuity of studies against other parasites.

Chagas disease is caused by Trypanosoma cruzi and affects the poorest population in the Americas.Fourteen plant extracts and seventeen sesquiterpene lactones from the tribe Vernonieae (Asteraceae), were evaluated for the first time against T. cruzi. Cytotoxicity employing HeLa cells was also assessed. The best results were obtained with leaves and flowers rinse extracts from Vernonanthura nebularum (E-1 and E-3) and Elephantopus mollis (E-11 and E-13), with IC 50 values < 2 µg/mL, being E-1 the most active (IC 50 =0.8 µg/mL). Additionally, these extracts displayed a good selectivity (SI >10). The most active sesquiterpene lactones, isolated from the extracts, were 2 (2-methoxy-2,5-epoxy-8-methacryloxygermacra-3Z,11(13)-dien-6,12-olide) and 6(2-ethoxy-2,5-epoxy-8-angeloxygermacra-3Z,11(13)-dien-6,12-olide) from V. nebularum and 12 (8α-methacryloxyhirsutinolide 13-O-acetate) from V. pinguis,with IC 50 of 1.5, 2.1 and 2.0 µM, respectively. These compounds showed SI values >14, better than those of the reference drug nifurtimox. Plants living in South American ecosystems could become a potential source of trypanocidal agents.

enfermedades parasitarias representan un problema de salud pública debido a su alta prevalencia por todo el mundo sobre todo en países en desarrollo, especialmente en áreas rurales y Bolivia no es la excepción. Objetivo. El presente estudio tuvo el objetivo de determinar la frecuencia y distribución de enteroparásitos en 8 municipios rurales del departamento de La Paz durante el periodo de agosto a septiembre de 2014. Materiales y Métodos. El trabajo es un estudio tipo transversal-descriptivo con un universo de trabajo de 1238 muestras de heces fecales conservadas con formol, las cuales fueron enviadas por el equipo médico de SUYANA (organización no gubernamental sin fines de lucro) a los laboratorios del Instituto SELADIS (Servicios de Laboratorio de Diagnóstico e Investigación en Salud). Resultados. Se realizaron estudios coproparasitológicos directos de cada una de las muestras y la observación microscópica dio los siguientes resultados. Se evidencio la presencia de enteroparásitos en 89,5% de la población estudiada, de los cuales 97,2% representan protozoarios tales como B. hominis, E. coli (protoozoos comensales) y G. lamblia (protozoo intestinal patógeno) los cuales estarían como los de mayor distribución, por otro lado el 2.8% de la población total corresponden a helmintos donde H. nana tiene una distribución de 1,8%, A. lumbricoides 0,7% y T. trichiura, S. stercoralis, Uncinarias estarían en el 0,1% de la población. También se pudo evidenciar que la mayor distribución de enteroparásitos estaría entre 1-10 años de edad (37,4%). Finalmente se evidencio que de las 8 poblaciones de estudio Charazani, Calacoto, Comanche presentarían mayor distribución de enteroparásitos (10-11 parásitos). Conclusión. Se evidencio que casi el 90% de la población en estudio, presentarían parásitos intestinales, con un claro predominio de los protozoarios sobre los helmintos. Esta información epidemiológica servirá de apoyo para mejorar los programas de salud en estas poblaciones. Palabras clave: Enteroparásitos, Protozoarios, Helmintos, poliparasitismo, área rural.