Insecticidal compounds fromPhellodendron amurense active againstDrosophila melanogaster

In the course of screening for novel naturally occurring insecticides from Chinese crude drugs, the methanolic extract of the bark of Phellodendron amurense Rupr was found to show insecticidal activity against larvae of Drosophila melanogaster Meigen. Two alkaloids, berberine (1) and palmatine (2), were isolated by bioassay-guided fractionation of the extract. Insecticidal activity against larvae of D melanogaster was demonstrated; 1 and 2 gave LC 50 values of 2.44 and 8.45 μmol ml -1 diet respectively. Acute toxicity against adult D melanogaster was also found; 1 had the more potent activity, with an LD 50 value of 19.0 μg per adult. However, 2 had weak activity in this study. Therefore 1 was identified as an insecticidal compound from the bark of P amurense Rupr. L'extrait methanolique de l'ecorce de Phellodendron amurense presente une activite insecticide contre les larves de Drosophila melanogaster Meigen. Dans cette etude, l'isolement et les activites des composes actifs sont decrits. Deux alcaloides, la berberine et la palmatine, sont isoles par un fractionnement biologique de l'extrait. La berberine est identifiee en tant que compose insecticide de l'ecorce de P. amurense.