Actividad Antifúngica de Polvos, Extractos y Fracciones de Cestrum nocturnum L. Sobre el Crecimiento Micelial de Rhizopus stolonifer (Ehrenb.:Fr.) Vuill.

the antifungal effects of leaf powders, extracts, and fractions of cestrum nocturnum from morelos state, mexico, were evaluated on three isolates of rhizopus stolonifer using mycelial inhibition bioassays. a dose-effect curve at concentrations of 0.5, 2, 5, and 10 mg/ml was observed in isolates from cuautla and san carlos. leaf powders had a significant inhibitory effect from 10 to 44%. ethanolic and aqueous extracts did not have effect on mycelial inhibition in any of the isolates at the three rates tested. acetonic extracts had an inhibitory effect from 2 to 22%. methanolic extracts had a significant inhibitory effect on isolates from cuautla (18 and 62%) and san carlos (14 and 76%), respectively, at 5 and 10 mg/ml. the isolate from yautepec showed a greater effect at the three rates tested with a mycelial inhibition from 46 to 94%. the methanolic extract was subjected to chromatography column, where two fractions 8-11 and 12-19 were isolated; these showed mycelial growth inhibition from 6 to 66% and from 8 to 50%, respectively, on the three isolates of r. stolonifer. a preliminary study showed that these fractions corresponded to steroidal saponins.