Fast identification of lipase inhibitors in oolong tea by using lipase functionalised Fe3O4 magnetic nanoparticles coupled with UPLC-MS/MS

Food Chem. 2015 Apr 15;173:521-6. doi: 10.1016/j.foodchem.2014.10.087. Epub 2014 Oct 23.

Abstract

Oolong tea is an important member in tea family, which claims for various health benefits such as preventing obesity and improving lipid metabolism. In this work, using pancreatic lipase (PL) functionalised magnetic nanoparticles (PL-MNPs) as solid phase extraction absorbent in combination with ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS), we developed a method for rapid screening and identification of lipase inhibitors from oolong tea. Three PL ligands were selectively extracted and identified as (-)-epigallocatechin-3-O-gallate (EGCG), (-)-gallocatechin-3-O-gallate (GCG) and (-)-epicatechin-3-O-gallate (ECG). Their lipase inhibitory activities were significantly higher than those non-ligands. Structure-activity analysis revealed that the presence of a galloyl moiety in the structure was required for binding to PL-MNPs, and therefore, exhibiting a strong inhibition on the enzyme. Taking advantages of the specificity in enzyme binding and the convenience of magnetic separation, this method has great potential for fast screening of lipase inhibitors from natural resources.

Keywords: (−)-Epicatechin-3-O-gallate (PubChem CID: 107905); (−)-Epigallocatechin-3-O-gallate (PubChem CID: 65064); (−)-Gallocatechin-3-O-gallate (PubChem CID: 44257114); Ligand fishing; Lipase inhibitors; Magnetic nanoparticles; Oolong tea; Pancreas lipase; UPLC–MS.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catechin / analogs & derivatives
  • Catechin / analysis
  • Chromatography, High Pressure Liquid / methods*
  • Enzyme Inhibitors / analysis*
  • Lipase / antagonists & inhibitors*
  • Magnetite Nanoparticles / chemistry*
  • Plant Extracts / chemistry
  • Tandem Mass Spectrometry / methods*
  • Tea / chemistry*

Substances

  • Enzyme Inhibitors
  • Magnetite Nanoparticles
  • Plant Extracts
  • Tea
  • gallocatechin gallate
  • Catechin
  • epicatechin gallate
  • epigallocatechin gallate
  • Lipase