车前子中黄嘌呤氧化酶抑制剂成分的电化学生物传感筛选研究

目的：采用电化学生物传感法，对车前子中分得的23个化合物进行黄嘌呤氧化酶抑制剂的筛选，并对有抑制作用的成分考察其抑制强度及酶动力学特征。方法：以黄嘌呤氧化酶为生物传感靶标，采用循环伏安法，基于不同浓度化合物对黄嘌呤氧化酶电化学催化黄嘌呤的传感电流信号的影响筛选黄嘌呤氧化酶抑制剂。结果：共筛选出7个黄嘌呤氧化酶抑制剂成分，分别为木犀草素、毛蕊花糖苷、金圣草黄素、吲哚-3-甲醛、圣草酚、（E）-3，4-二羟基苯亚甲基丙酮及二（2-乙基己基）-苯-1，2-羧酸酯，且均为竞争性抑制类型。其中木犀草素、毛蕊花糖苷、金圣草黄素IC₅₀依次为4.6、7.7、53.0 μg·mL^-1，抑制常数Ki分别为4.3、10.1、90.2 μg·mL^-1；吲哚-3-甲醛、圣草酚、（E）-3，4-二羟基苯亚甲基丙酮、二（2-乙基己基）-苯-1，2-羧酸酯最大抑制率分别为30.2%、22.7%、21.5%、10.3%，抑制常数Ki分别为68.2、73.0、136.4、141.7 μg·mL^-1。吲哚-3-甲醛，（E）-3，4-二羟基苯亚甲基丙酮及二（2-乙基己基）-苯-1，2-羧酸酯为新发现的黄嘌呤氧化酶抑制剂。结论：车前子中黄嘌呤氧化酶抑制剂有多种化合物类型，具有很好的开发应用前景。电化学生物传感筛选方法简单快捷，灵敏度与选择性高，筛选化合物用量低，在天然产物黄嘌呤氧化酶抑制剂的筛选中具有很好的应用前景。

Objective: To screen xanthine oxidase inhibitors of Plantaginis Semen using electrochemical biosensor method, and to investigate the enzyme inhibition kinetic characteristics. Method: The electrochemical bio-sensing method was applied to screen xanthine oxidase inhibitors from 23 compounds isolated from Plantaginis Semen. This method is based on the electrocatalytic signals of xanthine oxidase toward oxidation of xanthine using cyclic voltammetry. And the enzyme inhibition kinetic characteristics were also investigated. Results: Seven compounds of luteolin, acteoside, chrysoderol, 1H-indolo-3-carbaldehyde, eriodictyol, 4-(3, 4-dihydroxyphenyl)-3-buten-2-one, and bis(2-ethyth-exyl)-benzene-1, 2-dicarboxylate exhibit xanthine oxidase inhibited activities via competetive effects, the IC₅₀ of luteolin, acteoside and chrysoderol were 4.6 μg·mL^-1, 7.7 μg·mL^-1 and 53.0 μg·mL^-1, and the Ki was 4.3 μg·mL^-1, 10.1 μg·mL^-1, 90.2 μg·mL^-1, respectively.The maximum inhibition rate of1H-indolo-3-carbaldehyde, eriodictyol, 4-(3, 4-dihydroxyphenyl)-3-buten-2-one, and bis(2-ethythexyl)-benzene-1, 2-dicarboxylate was 30.2%, 22.7%, 21.5% and 10.3%, the Ki was 68.2 μg·mL^-1, 73.0 μg·mL^-1, 136.4 μg·mL^-1 and 141.7 μg·mL^-1. 1H-indolo-3-carbalde-hyde, eriodictyol, 4-(3, 4-dihydroxyphenyl)-3-buten-2-one, and bis(2-ethythexyl)-benz-ene-1, 2-dicarboxylate were discovered as xanthine oxidase inhibitors for the first time. Conclusion: The inhibitors from Plantaginis Semen obtaining multiple different compounds have good and prospect. The electrochemical biosensing method is selective, sensitive, rapid and convenient, it is hoped to be one of the most promising methods in the field of xanthine oxidase inhibitors research.