Screening and determination of potential xanthine oxidase inhibitors from Radix Salviae Miltiorrhizae using ultrafiltration liquid chromatography–mass spectrometry

Xanthine oxidase (XOD) inhibitors play an important role in the treatment of gout and many other diseases related to the superoxide anion metabolism. In this study, an ultrafiltration-liquid chromatography–mass spectrometry (UF-LC–MS) method was developed for the screening and identification of potential XOD inhibitors from Radix Salviae Miltiorrhizae extract. Eleven lipophilic diterpenoid quinines were identified as XOD inhibitors from the extract. The relationship between the structure and activity of the detected compounds was estimated on the basis of the UF-LC–MS data. The results demonstrate that the 1,2-naphthoquinone group is necessary for the XOD inhibitory activity of the compounds, and that furan and hydroxyl on the alicyclic ring could enhance the activity of the compounds at different levels. These results may explain and support the medical use of the extract of Radix S. Miltiorrhizae for the prevention and treatment of hyperuricemia and gout.

► UF-LC–MS method for screening XOD inhibitors was developed.
► Method is suited for rapid screening and characterization of XOD inhibitors from TCM.
► UF-LC–MS is a rapid, sensitivity and high throughput tool to screen XOD inhibitors.
► Eleven XOD inhibitors were screened from the Radix Salvia Miltiorrhizae extract.
► The relationship between the structure and activity of inhibitors was estimated.