TERMITE ANTIFEEDANT ACTIVITY IN TROPICAL PLANTS .2. TERMITE ANTIFEEDANT ACTIVITY IN AFRAMOMUM MELEGUETA

摘要

n-Hexane and methanolic seed extracts of Aframomum melegueta were studied for termite antifeedant activity against workers of Reticulitermes speratus. Strong antifeedant activity was observed when the termite workers were tested in a choice filter paper disk bioassay containing 1% crude extracts. Bioassay-directed fractionation led to the isolation of gingerdione, 5-oxo-1-(4-hydroxy-3-methoxyphenyl)decan-3-one, [6]-paradol, 1-(4-hydroxy-3-methoxyphenyl)decan-3-one, [6]-gingerol, 5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)decan-3-one and [6]-shogaol, 1-(4-hydroxy-3-methoxyphenyl)dec-5-en-3-one, as the antifeedant compounds. [6]-Gingerol and [6]-shogaol exhibited the strongest antifeedant activity at 1000 ppm, corresponding to 8 mu g cm(-2).