中文摘要：

苦瓜叶乙酸乙酯萃取物对多种害虫有明显的拒食、抑制生长发育和毒杀作用。为了进一步探讨其作用机制，测定了苦瓜叶乙酸乙酯萃取物对亚洲玉米螟幼虫Ostrinia furnacalis （Guenée）海藻糖酶、碱性磷酸酯酶、酸性磷酸酯酶、羧酸酯酶和谷胱甘肽-S-转移酶等代谢酶活性的影响。结果表明：苦瓜叶乙酸乙酯萃取物对亚洲玉米螟幼虫海藻糖酶、碱性磷酸酯酶和酸性磷酸酯酶活性均有明显的抑制作用，24 h-72 h，0.2%萃取物处理的海藻糖酶和碱性磷酸酯酶平均相对活力分别比对照减少了32.3%和34.1%；48 h和72 h，酸性磷酸酯酶相对活力分别比对照减少了56.8 %和38.0 %；0.05-0.2%萃取物处理酸性磷酸酯酶活性也明显被抑制。对羧酸酯酶活性的影响则表现为先抑制后诱导再恢复的趋势。对谷胱甘肽-S-转移酶活性表现出明显的诱导作用。结果提示苦瓜叶乙酸乙酯萃取物对亚洲玉米螟幼虫海藻糖酶、碱性磷酸酯酶和酸性磷酸酯酶等代谢酶的抑制作用可能是其抑制昆虫生长发育的主要作用机制之一。

英文摘要：

Ethyl acetate extracts of Momordica charantia leaves had significant antifeedant, inhibitive development activity and toxicity on many insect pests. In order to explore its insecticidal mechanism on insect, the effect of ethyl acetate extracts of M.charantia leaves on activities of trehalas, alkaline phosphatase, acid phosphatase, carboxyl esterases and GSH-S-transferase in larvae of the Asian corn borer, Ostrinia furnacalis were determined. The results showed that the activities of trehalas, alkaline phosphatase and acid phosphatase in tested larvae by ethyl acetate extracts of M.charantia leaves were inhibited obviously, the average relative activity of trehalas and alkaline phosphatase were decreased in treatment of 0.2%, decreased by 32.3% and 34.1% from 24 h to 72 h, compared to the controls, respectively; the relative activity of acid phosphatase were decreased by 56.8 % and 38.0 % in 48 h and 72 h, compared to the controls; With the concentration 0.05%-0.2% of ethyl acetate extracts of M.charantia leaves, the activity of acid phosphatase was also inhibited significantly. The activity of carboxyl esterases was inhibited firstly, then was activited. Extract can obviously induce the activity of glutathione-S-transferase. The result showed that inhibition of ethyl acetate extracts of M.charantia leaves to the activities of trehalas,alkaline phosphatase and acid phosphatase of O.Furnacalis may be one of its major mechanism of inhibition to insect on growth and development.