Rapid screening and isolation of 5‐lipoxygenase inhibitors in Inonotus obliquus and mechanism of action in the treatment of asthma

Abstract

Accurate screening and targeted preparative isolation of active substances in natural medicines have long been two technical challenges in natural medicine research. This study outlines a new approach to improve the efficiency of natural product preparation, focusing on rapidly and accurately screening potential active ingredients in Inonotus obliquus as well as efficiently preparing 5‐lipoxidase (5‐LOX) inhibitors, to provide new ideas for the treatment of asthma with Inonotus obliquus. First, we used ultrafiltration (UF) mass spectrometry to screen for three potential inhibitors of 5‐LOX in Inonotus obliquus. Subsequently, the inhibitory effect of the active ingredients screened in the UF assay on 5‐LOX was verified using the molecular docking technique, and the potential role of the active compounds in Inonotus obliquus for the treatment of asthma was analyzed by network pharmacology. Finally, based on the above activity screening guidelines, we used semi‐preparative liquid chromatography and consecutive high‐speed countercurrent chromatography to isolate three high‐purity 5‐LOX inhibitors such as betulin, lanosterol, and quercetin. Obviously, through the above approach, we have seamlessly combined rapid discovery, screening, and centralized preparation of the active ingredient with molecular‐level interactions between the active ingredient and the protease.