Phenoloxidase, an effective bioactivity target for botanical insecticide screening from green walnut husks.

Phenoloxidase, a critical enzyme in insects, may serve as a promising target in botanical insecticide development. In an effort to identify active ingredients with insecticidal properties in green walnut husks, juglone and plumbagin were isolated from the chloroform extract using phenoloxidase as bioactive target with the IC of 0.247 g/L and 0.256 g/L, respectively. After an artificial diet feeding of the juglone or plumbagin, more than 50% corrected mortality in stomach toxicity form was observed in Linne larvae and Hübner larvae at the concentration ≥0.01 g/L, the LC of juglone and plumbagin for two kinds of insects were determined as 0.012, 0.011 and 0.022, 0.030 g/L, respectively. This research indicated the significance of PO as bioactive target in pesticides identification and also shed light on the development of phenoloxidase inhibitor as promising botanical insecticides in the future.