Rapid screening and identification of bioactive compounds specifically binding to beta 2-adrenoceptor from San-ao decoction using affinity magnetic fine particles coupled with high-performance liquid chromatography–mass spectrometry

BACKGROUND: San-ao decoction (SAD) has been widely used in Chinese medicine against respiratory diseases, such as asthma and rhinallergosis. The bioactive compounds for such pharmacological action remain unknown. METHODS: We developed a methodology to isolate the bioactive compounds of SAD. The assay involved the immobilization of beta 2-adrenoceptor (β(2)-AR) onto magnetic fine particles, the capture of target compounds by the immobilized receptor, the identification of the receptor bound compounds by reversed-phase high-performance liquid chromatography coupled with tandem mass spectrometry. RESULTS: Vicenin, shaftoside, isoshaftoside, liquiritin apioside and isoliquiritin apioside were identified as β(2)-AR ligands in SAD extract. The binding of these compounds to β(2)-AR occurred on serine(169), serine(170) and phenylalanine(256) of the receptor. CONCLUSIONS: The developed methodology has high stability and specificity for recognizing and isolating target compounds. It is an alternative method for rapidly screening bioactive compounds of immobilized receptor from Chinese prescriptions. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13020-018-0207-8) contains supplementary material, which is available to authorized users.