关键词: 黄胸散白蚁, 马缨丹提取物, 纤维素酶, 解毒酶, 杀虫作用机制

Abstract: [Objective]In order to explore the action mechanisms, the effects of 3 different solvent extracts from Lantana camara (Verbenaceae) leaves on cellulose and detoxification enzyme in the termite Reticulitermes flaviceps (Isoptera: Rhinotermitidae) were studied.[Method]Termites were fed with filter paper saturated with 3 different solvent extracts of L. camara leaves for different times, and then we measured the enzymes activities of endo-β-1,4-glycanase (EG), exo-β-1,4-glucanase (CBH), β-1,4-glucosidase (BG), carboxylesterase (CarE), glutathione-S-transferase (GSTs) and mixed-functional oxidase (MFO). [Result]The all extracts had to some degree inhibiting effects on the six enzymes activities, however there were differences in the inhibition with extracts of chloroform, ethyl acetate and petroleum ether at 6-72 h. As for the three cellulose enzymes, the chloroform extract had no significant effect on EG, but had significantly inhibiting effect on CBH and BG, especially on CBH with the highest inhibition rate of 17.61% at 72 h. The ethyl acetate extract also had inhibiting effect on the 3 enzymes activities, with relatively stronger inhibition on EG and BG, and the inhibition rate on EG was 27.18% at 48 h, and 29.28% at 24 h, respectively. The petroleum ether extract had no significant effect on CBH, but had strongly inhibited on EG and BG, with the highest inhibition rate of 39.89% on EG at 72 h. As for the three detoxification enzymes, the 3 extracts had no significant effect on CarE, but had inhibiting effect on GSTs, which mainly occurred at 12-48 h. The ethyl acetate extract had the strongest inhibition, with the highest inhibition rate of 39.54% at 36 h. The MFO activities fluctuated after being treated with 3 extracts, and the relatively stronger inhibition on the 3 detoxification enzymes occurred at 12 h and 36 h. [Conclusion] The extracts of chloroform, ethyl acetate and petroleum ether could decrease the cellulose and detoxification enzymes activities, disrupting the normal physiological metabolism.

Key words: Reticulitermes flaviceps, Lantana camara extract, cellulose enzyme, detoxification enzyme, insecticidal mechanism