The ethanol extract of Chinese medicinal herb,Evodia rutaecarpaHort unripe fruits, was found to possess nematocidal activity against the root-knot nematodes,Meloidogyne incognita, during the screening program for new agrochemicals from local wild plants and Chinese medicinal herbs. Bioactivity-guided chromatographic separation of the ethanol extract ofE. rutaecarpaon repeated silica gel columns led to isolate five constituent components (two limonoids, evodol and limonin; three alkaloids, evodiamine, rutaecarpine, and wuchuyuamide I). Evodiamine (LC50=73.55 μg/mL) and rutaecarpine (LC50=120.85 μg/mL) exhibited stronger nematocidal activity againstM. incognitathan the crude ethanol extract ofE. rutaecarpa(LC50=131.54 μg/mL). Wuchuyuamide I, evodol, and limonin also possessed nematocidal activity againstM. incognitawith LC50values of 147.87 μg/mL, 155.02 μg/mL, and 197.37 μg/mL, respectively, but weaker than the crude ethanol extract ofE. rutaecarpa.
Synthesis and nematocidal activity of ascaridole derivatives against Meloidogyne incognita and Aphelenchoides besseyi
