Étude cytologique du mode d'action du capsidiol, sur les hyphes de Phytophthora capsici

Abstract

After the action of capsidiol on the hyphae of Phytophthora capsici in vitro, observations with electron microscopy revealed alterations in the cell wall, in the plasmalemma, in the mitochondria, and in the Golgi system. Among other effects, phytoalexin stimulated the separation of the external cell wall layers, liberating a three-component filament. Such cytomorphological events were also recorded in situ on sections, when the fungus parasitized the leaves of Capsicum annuum. [Translated by the Journal]

Terpenoid phytoalexins

“…It was postulated that dehydrogenation could follow to yield 3,4-dehydroisolubimin (83) : there was tentative evidence, based on GC-MS, for the presence of this compound as a transient intermediate. Cyclization would then afford cyclodehydroisolubimin (84) as the precursor of cyclolubimin (85) and of the epoxides (86) and (87). The intermediacy of ( 83) is consistent with observed incorporation of a deuterium atom at C-3 of (84) following incubation of lubimin with G .…”