[[Anti-leishmanial activity in plants from a Biological Reserve of Costa Rica]. / Actividad contra Leishmania sp. (Kinetoplastida: Trypanosomatidae) de plantas en una Reserva Biológica de Costa Rica.

Leishmaniosis is an important human disease very difficult to treat. For this reason, many researchers in the world have been look- ing for anti-leishmanial chemical components present in several plant species. In Costa Rica, since no studies have been done in this field, this work aimed at the search of active chemical components in local plants that may have an activity against Leishmania sp. A total of 67 plants were selected from the Alberto Manuel Brenes Biological Reserve (REBAMB). For these collected plants, fresh or dried hidroalcoholic extracts of root, stem, mature or young leaves, flowers, and immature or mature fruits, were prepared under conventional methods. All extracts were tested for their effect against a strain of Leishmania (OCR with known characteristics). Firstly, by presumptive tests, we selected only those with some activity, and then, more specific studies were done to determine the IC50 in µg/mL; a promising plant was considered only if at least one of its parts presented an IC50 < 100 µg/mL. Under this parameter, the following active plants were obtained and their lowest and highest IC50 obtained values presented (µg/mL): Bocconia frutescens (0.6 and 66.7), Clematis dioica (27.5 and 44.4), Cordia megalantha (80.0), Eugenia austin-smithi (90.6), Guarea bullata (98.8), Guateria tonduzii (44.4 and 66.3), Mikania holwayana (45.0 and 95.6), Nectandra membranacea (44.5 and 58.6), Neurolaena lobata (25.0 and 100.0), Persea povedae (76.9), Piper auritum (60.0), Rollinia pittieri (43.1), Solanum arboreum (25.8 and 72.5), Tetrorchidiumn eurphyllum (53.8 and 95.0), Witheringia solanacea (15.9 and 98.1) and Zanthoxylum juniperinum (23.4 and 97.5). Although the parasitic effect of fresh or dried extracts were almost similar, the fresh material slightly showed better results. That anti-parasitic effect occurred in one or more than four parts of the plant. Most of the active extracts did not produce lysis and aglutination which indicates a low toxicity. Since the species studied are different from those analyzed by other authors, we discuss the importance of these new findings, in relation to the new scientific knowledge, and the possible use of these plants as a leishmaniosis treatment.

Actividad in vitro anti-Leishmania (Trypanosomatidae) del epóxido trans-Z-&-bisaboleno y del Safrol, en frutos de Piper auritum (Piperaceae) / Anti-Leishmania (Trypanosomatidae) activity of trans-Z-&-bisabolene epoxide and isolation of safrole, in fruits of Piper auritum (Piperaceae)

Resumen La leishmaniasis es una enfermedad con una alta incidencia en el ser humano, que puede ser controlada, pero como los tratamientos tienen efectos secundarios importantes se han realizado estudios de diversas plantas con el fin de encontrar compuestos con actividad antileishmaniásica que presenten pocos efectos nocivos para el ser humano. El presente estudio consistió en realizar un tamizaje fitoquímico de la planta, para identificar la presencia de cumarinas, terpenos, triterpenos y azúcares reductores. El objetivo fue encontrar componentes químicos puros con actividad contra el parásito Leishmania sp. Por tal razón se purificaron los compuestos: trans-Z-alfabisaboleno y el Safrol, a los que se les realizaron pruebas del efecto anti parasitario que presentaron un CI50 de 50.0 µg/mL y 0.0 µg/mL, respectivamente. Además, se discute la importancia de estos nuevos hallazgos. El compuesto mayoritario presente en los aceites esenciales (Safrol) no es el componente que presentó la actividad. Es importante realizar estudios sobre su proyección en el tratamiento de la leishmaniasis.

Abstract The leishmaniosis disease incidence is high in tropical regions, and its current treatment has shown severe secondary effects. Considering this problem, many studies have focused on plants, looking for chemical components that have anti-leishmanial activity, and are free of adverse effects for human beings. The purpose of this work was to find a chemical component with this kind of activity in Piper auritum. In a phytochemical screening of this plant, we found some cumarins, terpens, triterpens and reducing sugars; and later, we identified the components trans-Z-α-bisabolene epoxide and Safrol. The first component presented a CI50 of 50.0 µg/mL of anti-Leishmania activity. The Safrol, which is the major component of the essential oils of this plant, did not show antiparasitic activity. These results are discussed considering treatment of leishmaniasis. Rev. Biol. Trop. 66(2): 826-835. Epub 2018 June 01.

Actividad contra Leishmania sp. (Kinetoplastida: Trypanosomatidae) de plantas en una Reserva Biológica de Costa Rica / Anti-leishmanial activity in plants from a Biological Reserve of Costa Rica

Leishmaniosis is an important human disease very difficult to treat. For this reason, many researchers in the world have been looking for anti-leishmanial chemical components present in several plant species. In Costa Rica, since no studies have been done in this field, this work aimed at the search of active chemical components in local plants that may have an activity against Leishmania sp. A total of 67 plants were selected from the Alberto Manuel Brenes Biological Reserve (REBAMB). For these collected plants, fresh or dried hidroalcoholic extracts of root, stem, mature or young leaves, flowers, and immature or mature fruits, were prepared under conventional methods. All extracts were tested for their effectagainst a strain of Leishmania (OCR with known characteristics). Firstly, by presumptive tests, we selected only those with some activity, and then, more specific studies were done to determine the IC50 in µg/mL; a promising plant was considered only if at least one of its parts presented an IC50<100µg/mL. Under this parameter, the following active plants were obtained and their lowest and highest IC50 obtained values presented (µg/mL): Bocconia frutescens (0.6 and 66.7), Clematis dioica (27.5 and 44.4), Cordia megalantha (80.0), Eugenia austin-smithi (90.6), Guarea bullata (98.8), Guateria tonduzii (44.4 and 66.3), Mikania holwayana (45.0 and 95.6), Nectandra membranacea (44.5 and 58.6), Neurolaena lobata (25.0 and 100.0), Persea povedae (76.9), Piper auritum (60.0), Rollinia pittieri (43.1), Solanum arboreum (25.8 and 72.5), Tetrorchidium euryphyllum (53.8 and 95.0), Witheringia solanacea (15.9 and 98.1) and Zanthoxylum juniperinum (23.4 and 97.5). Although the parasitic effect of fresh or dried extracts were almost similar, the fresh material slightly showed better results. That anti-parasitic effect occurred in one or more than four parts of the plant.Most of the active extracts did not produce lysis and aglutination which indicates a low toxicity. Since the species studied are different from those analyzed by other authors, we discuss the importance of these new findings, in relation to the new scientific knowledge, and the possible use of these plants as a leishmaniosis treatment. Rev. Biol. Trop. 62 (3): 1229-1240. Epub 2014 September 01.

La leishmaniosis es una enfermedad muy importante para el ser humano pero su tratamiento es bastante difícil. Por esta razón muchos investigadores han venido buscando plantas que contengan componentes químicos activos contra esta parasitosis. En Costa Rica no se tienen estudios al respecto y por eso el objetivo de este estudio fue la búsqueda de componentes activos contra Leishmania sp. en plantas de Costa Rica; 67 especies de la Reserva Biológica Alberto Manuel Brenes (REBAMB) fueron seleccionadas para realizar este trabajo. Para ello se prepararon extractos crudos hidro-alcohólicos de material fresco o desecado de raíz, tallo, hojas maduras o tiernas, flores y frutos inmaduros o maduros. Usando pruebas presuntivas y luego específicas, se analizó el efecto de tales extractos sobre una cepa de Leishmania (OCR). Se consideraron plantas promisorias solamente aquellas en que al menos una de sus partes presentara un CI50<100µg/mL. Las plantas seleccionadas fueron: Bocconia frutescens, Clematis dioica,Cordia megalantha, Eugenia austin-smithii, Guarea bullata, Guateria tonduzii, Mikania holwayana, Nectandra membranacea,Neurolaena lobata, Persea povedae, Piper auritum, Rollinia pittieri, Solanum arboreum, Tetrorchidium euryphyllum, Witheringia solanacea y Zanthoxylum juniperinum. Existió una ligera tendencia de positividad mayor para los extractos frescos y la actividad se presentó en una y hasta más de cuatro partes de la planta. La mayoría de los extractos activos no fueron tóxicos. Se discute la importancia de estos nuevos hallazgos, en relación con el nuevo conocimiento científico y su proyección en el tratamiento de la leishmaniosis.