RESUMEN
Bioassay-guided fractionation of the crude extract (80% EtOH) of the leaves of Cestrum schlechtendahlii, a plant used by Q'eqchi' Maya healers for treatment of athlete's foot, resulted in the isolation and identification of two spirostanol saponins (1 and 2). Structure elucidation by MS, 1D-NMR, and 2D-NMR spectroscopic methods identified them to be the known saponin (25R)-1ß,2α-dihydroxy-5α-spirostan-3-ß-yl-O-α-L-rhamnopyranosyl-(1 â 2)-ß-D-galactopyranoside (1) and new saponin (25R)-1ß,2α-dihydroxy-5α-spirostan-3-ß-yl-O-ß-D-galactopyranoside (2). While 2 showed little or no antifungal activity at the highest concentration tested, 1 inhibited growth of Saccharomyces cerevisiae (minimum inhibitory concentration (MIC) of 15-25 µM), Candida albicans, Cryptococcus neoformans, and Fusarium graminearum (MIC of 132-198 µM).
Asunto(s)
Antifúngicos/farmacología , Cestrum/química , Hongos/efectos de los fármacos , Extractos Vegetales/farmacología , Saponinas/farmacología , Espirostanos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Candida albicans/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Etnicidad , Fusarium/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Medicina Tradicional , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fitoterapia , Extractos Vegetales/química , Hojas de la Planta/química , Plantas Medicinales , Saccharomyces cerevisiae/efectos de los fármacos , Saponinas/química , Saponinas/aislamiento & purificación , Solanaceae , Espirostanos/química , Espirostanos/aislamiento & purificaciónRESUMEN
The widespread use of Neurolaena lobata (L.) R. Br. ex Cass. by Q'eqchi' Maya and indigenous healers throughout the Caribbean for inflammatory conditions prompted the study of the anti-inflammatory activity of this traditional medicine. The objectives of this study were to conduct a detailed ethnobotanical investigation of the uses of N. lobata by the Q'eqchi' Maya of Belize for a variety of inflammatory symptoms and to evaluate the in vitro anti-inflammatory activity of leaf extract and isolated sesquiterpene lactones. The crude 80% EtOH extract of N. lobata leaves administered at 100 µg/mL reduced LPS-stimulated TNF-α production in THP-1 monocytes by 72% relative to the stimulated vehicle control. Isolated sesquiterpene lactones, neurolenins B, C+D, lobatin B and 9α-hydroxy-8ß-isovalerianyloxy-calyculatolide were more active (IC50=0.17-2.32 µM) than the positive control parthenolide (IC50=4.79 µM). The results provide a pharmacological and phytochemical basis for the traditional use of this leaf for inflammatory conditions.