超滤亲和结合液相色谱-质谱联用和分子对接技术筛选毛菊苣种子中高亲和性α-葡萄糖苷酶抑制剂

Screening of High-Affinity α-Glucosidase Inhibitors from Cichorium Glandulosum Boiss. et Hout Seed Based on Ultrafiltration Liquid Chromatography-Mass Spectrometry and Molecular Docking

采用超滤亲和结合液相色谱-质谱联用(UF-LC-MS)和分子对接技术筛选毛菊苣种子中高亲和α-葡萄糖苷酶抑制剂。以4-硝基苯-α-D-吡喃葡萄糖苷(PNPG)为底物,阿卡波糖为阳性对照,评价毛菊苣种子提取物对α-葡萄糖苷酶的抑制活性,其中阿卡波糖IC_(50)为0.003 mg/m L,毛菊苣种子IC_(50)为0.447 mg/m L。利用UF-LC-MS技术对毛菊苣种子提取物进行筛选鉴定,获得4种化合物;通过Autodock软件筛选出2种与α-葡萄糖苷酶有较高亲和力的化合物,分别是绿原酸和异绿原酸A。结合体外酶活实验,验证了绿原酸、异绿原酸A对α-葡萄糖苷酶的抑制活性。结果表明,各化合物对α-葡萄糖苷酶的抑制活性由大到小依次是:阿卡波糖>异绿原酸A>绿原酸,其中异绿原酸A与阿卡波糖抑制率相近。

High-affinity α-glucosidase inhibitors were screened from Cichorium glundulosum Boiss. et Hout seed( CGS) extract by ultra-filtration affinity-liquid chromatography-mass spectrometry( UF-LC-MS) and molecular docking. By taking 4-nitrobenzene-α-D-glucopyranoside( PNPG) as substrate and acarbose as positive control to evaluate the inhibitory activity of CGS extract,IC50 of acarbose and CGS extract were0.003 mg/m L and 0. 447 mg/m L,respectively. Meanwhile,4 compounds from CGS extract by UF-LC-MS were screened and identified. Then by using autodock software,the compounds that combined with α-glucosidase were well screened out,including chlorogenic acid and isochlorogenic acid A. The inhibitory activity of chlorogenic acid and chlorogenic acid A against α-glucosidase was verified in vitro. The results showed that the inhibitory activity of the compounds toward α-glucosidase presented the sequence of acarbose>isochlorogenic acid A>chlorogenic acid. The inhibition rate of isochlorogenic acid A was close to acarbose. The experimental results illustrated that UF-LC-MS and molecular docking could be used to screen high affinity enzyme inhibitors from CGS.