2-羟基-4-甲氧基苯甲醛缩苯胺对菜青虫酚氧化酶的抑制作用

为筛选对十字花科蔬菜害虫菜青虫Pieris rapae（L.）酚氧化酶具有高抑制活性的化合物，为寻找新型害虫控制剂提供线索，采用酶标仪微量法以室内合成、筛选的高活性化合物2-羟基-4-甲氧基苯甲醛缩苯胺为抑制剂，研究了其对菜青虫酚氧化酶的抑制活性及抑制类型。结果表明，供试化合物对菜青虫酚氧化酶的抑制中浓度（IC₅₀）为0.116 mmol/L；该化合物为典型的可逆非竞争型抑制剂，抑制常数（K_i）为1.96 mmol/L。该化合物直接对靶标酚氧化酶产生作用，而不是通过影响酶结构内的铜离子来产生作用的。

Inhibitory effects of 2-hydroxy-4-methoxybenzylidene-aniline on phenoloxidase from Pieris rapae(L.) (Lepidoptera: Pieridae)

To screen the obvious inhibitors of phenoloxidase (PO) from Pieris rapae (L.) and search after a theoretic foundation for developing the insecticide with novel modes of action, the inhibitory effects of 2-hydroxy-4-methoxybenzylidene-aniline as an inhibitor on PO from P. rapae, which had been partially purified, was studied by using microtitration assay. The results showed that the tested compound could inhibit PO activity obviously and the inhibitor concentration leading to 50% activity loss (IC₅₀) was estimated to be 0.116 mmol/L. The inhibitor was found to be a reversible noncompetitive inhibitor, and the K_i value was determined to be 1.96 mmol/L for the compound. Although the compound could affect PO directly, it did not chelate copper of PO active center.