A new method based on ligand fishing combined with high-performance liquid chromatography quadrupole-time-of-flight mass spectrometer and molecular docking was established to screen α-glucosidase inhibitors from a traditional Chinese medicine Morus alba root bark. α-Glucosidase was immobilized on magnetic nanoparticles, used as a solid support to incubate with crude extract. After ligand fishing, the eluates were analyzed by high-performance liquid chromatography quadrupole-time-of-flight mass spectrometer, obtaining eleven ligands (1–4, 6–12) eventually. In order to discriminate the non-specific binders and discover powerful enzyme inhibitors, molecular docking was further performed and three of the eleven ligands were optimized to be excellent α-glucosidase inhibitors by the confirmation of isolation and bioassay of individual compounds. These three ligands, sanggenons G (6), O (7) and sanggenol G (12) exhibited striking inhibitory activities with extremely low IC₅₀ values. The results suggest that established method will be applied to a wide range of target protein to screen potential bioactive constituents from herbal medicines.

建立了一种基于配体捕捞结合高效液相色谱四极杆飞行时间质谱仪和分子对接的新方法，从中药桑叶根皮中筛选α-葡萄糖苷酶抑制剂。将α-葡萄糖苷酶固定在磁性纳米颗粒上，用作与粗提物一起孵育的固体支持物。配体钓鱼后，将洗脱物通过高效液相色谱法四极杆-时间飞行质谱仪分析，获得11点的配体（1 - 4，6 - 12） 最终。为了区分非特异性结合剂并发现强大的酶抑制剂，进一步进行了分子对接，并通过确认了各个化合物的分离和生物测定，对11个配体中的3个进行了优化，使其成为出色的α-葡萄糖苷酶抑制剂。这三个配体，sanggenons G（6），O（7）和sanggenol G（12）表现出惊人的抑制活性，IC ₅₀值极低。结果表明，已建立的方法将应用于广泛的靶蛋白，以从草药中筛选潜在的生物活性成分。