Ligand-fishing and bioactivity-correlated metabolomics for accelerated discovery of antidiabetic drug leads

In recent years, hyphenation of analytical-scale high-performance liquid chromatography and high-resolution mass spectrometry with solid-phase extraction and nuclear magnetic resonance spectroscopy, i.e., HPLC-HRMS-SPE-NMR, has proven successful for dereplication as well as full structure elucidation directly from crude extracts without any prepurification steps [1 – 3]. However, the HPLC-HRMS-SPE-NMR technology is exclusively a chemical analysis tool and does not give any information about the bioactivity of individual constituents in the crude extract. Thus, the recent development of microplate-based high-resolution bioassays [4], ligand fishing [5] and bioactivity-correlated metabolomics has allowed targeting subsequent HPLC-HRMS-SPE-NMR experiments towards the bioactive constituents only – as indicated in the figure below.

In this talk, the principles of ligand-fishing technologies and bioactivity-correlated metabolomics in combination with HPLC-HRMS-SPE-NMR analysis will be outlined. Thus, ligand-fishing using α-glucosidase immobilized on magnetic beads were used to effectively fish out myricetin 3-O-α-L-rhamnopyranoside, myricetin, quercetin, and kaempferol as α-glucosidase inhibitors in crude extract of Eugenia catharinae [5], and bioactivity-labelling of ¹H NMR spectra of crude extracts of Radix astragalii were used for facilitating visual interpretation of scores in principal component analysis. Both methods were combined with HPLC-HRMS-SPE-NMR for structural elucidation of analytes.

Acknowledgements: Arife Önder is acknowledged for technical assistance.

Keywords: High-resolution bioassay, ligand-fishing, metabolomics, HPLC-HRMS-SPE-NMR.

References:

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