RESUMEN
Chia (Salvia polystachya Ort., Lamiaceae) is frequently used in Mexican traditional medicine to treat dysentery. In this study the main neo-clerodane diterpenes (polystachynes A, B and D, as well as linearolactone) were isolated from the aerial parts of chia, and their antiprotozoal activities toward Entamoeba histolytica and Giardia lamblia trophozoites were evaluated in vitro. Linearolactone was the most potent antiamoebic and antigiardial compound with IC(50) values of 22.9 microM for E. histolytica and 28.2 microM for G. lamblia. Polystachynes A, B and D, showed moderate antiprotozoal activity against both protozoans with IC(50) values ranging from 117.0 to 160.6 microM for E. histolytica and from 107.5 to 134.7 microM for G. lamblia. These data suggest that linearolactone may play an important role in the antidiarrhoeal activity of S. polystachya.
Asunto(s)
Antiprotozoarios/farmacología , Diterpenos de Tipo Clerodano/farmacología , Entamoeba histolytica/efectos de los fármacos , Giardia lamblia/efectos de los fármacos , Salvia/química , Antiprotozoarios/aislamiento & purificación , Diterpenos de Tipo Clerodano/aislamiento & purificación , Concentración 50 Inhibidora , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/farmacologíaRESUMEN
In this paper are reported the synthesis and antiprotozoal activity in vitro of 24 1-methylbenzimidazole derivatives (13-36) substituted at position 2 with aminocarbonyl, N-methylaminocarbonyl, N,N-dimethylaminocarbonyl, ethoxycarbonyl, 1-hydroxyethyl and acetyl groups, some of them with chlorine atoms at the benzenoid ring. Compounds 13-36 were more active than metronidazole, the choice drug against Giardia intestinalis and most of them against Trichomonas vaginalis. The most active group of compounds for both parasites was that with a 2-ethoxycarbonyl group (16, 22, 28, 34), independently of the substitution pattern at the benzenoid ring.
Asunto(s)
Antiprotozoarios/síntesis química , Antiprotozoarios/farmacología , Bencimidazoles/síntesis química , Bencimidazoles/farmacología , Antiprotozoarios/química , Bencimidazoles/química , Pruebas de Sensibilidad Microbiana , Pruebas de Sensibilidad Parasitaria , Relación Estructura-ActividadRESUMEN
Crude methanolic extracts from 22 Mexican medicinal plants were screened for antitrichomonal activity against Trichomonas vaginalis, which is the etiological agent of trichomoniasis. Among the plants tested Carica papaya and Cocos nucifera showed the best antitrichomonal activity with IC(50) values of 5.6 and 5.8 microg/ml, respectively. The extracts of Bocconia frutescens, Geranium mexicanum, and Lygodium venustum showed moderate activity with IC(50) values ranging from 30.9 to 60.9 microg/ml. All the other plant extracts were inactive (IC(50)>100 microg/ml). All extracts tested were less active than metronidazole (IC(50) 0.037 microg/ml), an antiprotozoal drug used as positive control. The results of the antiprotozoal screening support the popular uses of five of the plants tested for the treatment of some urogenital tract disorders in Mexican traditional medicine. However, seeds of Carica papaya and aerial parts of Bocconia frutescens should be used in herbal medicine with care to avoid toxicity.