Screening of lipase inhibitors from bamboo leaves based on the magnetic ligand fishing combined with HPLC/MS

Bamboo leaf is known as dietic tea for the prevention of obesity in China. To screen lipase inhibitors from bamboo leaf extract rapidly, lipase functionalized magnetic ligand fishing combined with HPLC/MS was established. Firstly, lipase was immobilized on magnetic nanoparticles by dialdehyde starch to obtain lipase-functionalized magnetic nanoparticles (L-MNPs), and then the L-MNPs were incubated with bamboo leaf extract to fish out ligands. Three enzyme inhibitors were obtained and identified as isoorientin, orientin, isovitexin by HPLC/MS. The results provided a powerful evidence for explaining the hypolipidemic effects of bamboo leaf extract, and this ligand fishing method is feasible for screening enzyme inhibitors from complex mixtures.