【目的】探讨石斛酚(gigantol)对诱导型一氧化氮合酶(iNOS)的抑制活性及作用位点,阐明石斛酚抗白内障的作用机制。【方法】采用试剂盒方法测定石斛酚对iNOS的体外抑制活性,动力学模拟石斛酚和iNOS的结合方式。【结果】浓度为120μmol/L的石斛酚对iNOS的抑制率为100%,其半数抑制量(IC50)为(32.227±5.73)μmol/L;石斛酚通过对iNOS活性位点的直接作用,进而抑制NO的产生;两者作用氨基酸位点是lle195、Gln257,相互作用力主要为氢键。【结论】石斛酚对iNOS具有良好的抑制作用。 【Objective】 To investigate the inhibitory activity of gigantol on inducible nitric oxide synthase (iNOS) and its site of action to elucidate the mechanism of action of gigantol against cataract. 【Method】 The kit assay was used to determine the inhibitory activity of gigantol on iNOS in vitro. The kinetics simulated the binding mode of gigantol and iNOS. 【Result】 The results showed that the inhibition rate of iNOS was 100% at a concentration of 120μmol / L, and the IC50 value was (32.227 ± 5.73) μmol / L. With the direct effect of gigantol on iNOS active sites, Inhibit the production of NO; ​​the two amino acid sites are lle195, Gln257, the interaction force is mainly hydrogen bond. 【Conclusion】 Endosulfan has a good inhibitory effect on iNOS.