Tyrosinase inhibitors can alleviate the harm to the liver caused by tyrosinase. How to effectively screen out natural tyrosinase inhibitors becomes a focus. In this study, Isodon excisoides was first extracted with the ultrasound optimized by response surface methodology. Then, a method combined ultrafiltration with ultra-liquid chromatography mass spectrometry (UHPLC/MS) was built to screen and identify tyrosinase inhibitors. The binding energies of active ingredients to tyrosinase were calculated by molecular docking. The reliability of the results was validated by the IC₅₀ of enzyme inhibition assay. As a result, the binding energies of 7 components including excisanin B, lasiokaurin, rabdophyllin G, rabdoserrin B, rabdosin D, rabdosinate and weisiensin were lower than that of resveratrol. It was indicated that these components had high tyrosinase inhibitory activity. The IC₅₀ values of lasiokaurin and excisanin B were 177 and 142 μmol/mL, which were less than that of resveratrol (183 μmol/mL). It showed that this way was simple, rapid, reliable and effective, which provided a new strategy to screen natural bioactive compounds from plants.

中文翻译：

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通过超滤结合 UHPLC-Q-TOF-MS 和分子对接技术筛选和评估异齿龙中酪氨酸酶抑制剂的能力

酪氨酸酶抑制剂可以减轻酪氨酸酶对肝脏的危害。如何有效筛选出天然酪氨酸酶抑制剂成为研究热点。在这项研究中，首先使用响应面方法优化的超声波提取了Isodon excisoides 。然后，建立了超滤与超液相色谱质谱（UHPLC/MS）相结合的方法来筛选和鉴定酪氨酸酶抑制剂。通过分子对接计算活性成分与酪氨酸酶的结合能。结果的可靠性通过 IC _50验证酶抑制试验。结果表明，excisanin B、lasiokaurin、rabdophyllin G、rabdoserrin B、rabdosin D、rabdosinate 和weisiensin 7 种成分的结合能低于白藜芦醇。表明这些成分具有高酪氨酸酶抑制活性。lasiokaurin 和 excisanin B的 IC ₅₀值分别为 177 和 142 μmol/mL，低于白藜芦醇 (183 μmol/mL)。表明该方法简单、快速、可靠、有效，为从植物中筛选天然生物活性化合物提供了一种新策略。