Antifungal activity against Colletotrichum acutatum and Colletotrichum gloeosporioides of the major constituents from wood sawdust of Platymiscium gracile Benth

[摘要] The tree tomato (Solanum betaceum Cav., Solanaceae) anthracnose, caused by the fungi Colletotrichum acutatum and Colletotrichum gloeosporioides, is the most important disease of this crop in Colombia for its wide distribution and the losses it causes. In the present work, the in vitro antifungal activity of the soluble fractions in n-hexane, dichloromethane, and ethyl acetate, and their major constituents from the sawdust of timber specie Platymiscium gracile Benth. (Fabaceae) against both fungi was evaluated. The n-hexane-soluble fraction exhibited the greatest inhibitory effect. The metabolites homopterocarpin (a pterocarpan, 0.39% dry weight), calycosin (an isoflavone, 2.01%) and scoparone (a coumarin, 1.48%) were isolated for the first time from wood sawdust of P. gracile. The structure of these compounds was determined by 1H and 13C NMR analyses. The three compounds tested showed significant antifungal activity.Keywords: P. gracile, C. gloeosporioides, C. acutatum, homopterocarpin, calycosin, scoparone.

[学科分类] 植物学

[关键词] La antracnosis del tomate de xc3xa1rbol (Solanum betaceum Cav.;Solanaceae);ocasionada por los hongos Colletotrichum acutatum y Colletotrichum gloeosporioides;es la enfermedad mxc3xa1s importante de este cultivo en Colombia por su amplia distribucixc3xb3n y las pxc3xa9rdidas que ocasiona. En el presente trabajo se evaluxc3xb3 la actividad antifxc3xbangica in vitro de las fracciones solubles en n-hexano;diclorometano y acetato de etilo;y sus componentes mayoritarios;del aserrxc3xadn de la especie maderable Platymiscium gracile Benth. (Fabaceae);contra ambos hongos. La fraccixc3xb3n en n-hexano exhibixc3xb3 el mayor efecto inhibitorio. Los metabolitos homopterocarpina (un pterocarpano;0.39% del peso seco de aserrxc3xadn);calicosin (una isoflavona;2.01%) y escoparona (una cumarina;1.48%) se aislaron por primera vez desde el aserrxc3xadn de madera de P. gracile empleando txc3xa9cnicas cromatogrxc3xa1ficas. La estructura de los compuestos se determinxc3xb3 por anxc3xa1lisis de RMN de 1H y 13C. Los tres metabolitos mostraron una actividad antifxc3xbangica significativa contra ambos hongos.