Pure Shift Nuclear Magnetic Resonance: a New Tool for Plant Metabolomics

Lopez J.M.; Leyva V.; Maruenda H. · Journal of Visualized Experiments (2021) · DOI: 10.3791/62719

Resumen

Nuclear Magnetic Resonance (NMR) is one of the most powerful tools used in metabolomics. It stands as a highly accurate and reproducible method that not only provides quantitative data but also permits structural identification of the metabolites present in complex mixtures. Metabolic profiling by1 H NMR has proven useful in the study of various types of plant scenarios, which include the evaluation of crop conditions, harvest and post-harvest treatments, metabolic phenotyping, metabolic pathways, gene regulation, identification of biomarkers, chemotaxonomy, quality control, denomination of origin, among others. However, signal overlapping of the large number of resonances with expanded J-coupling multiplicities complicates the spectra analysis and its interpretation, and represents a limitation for classical1 H NMR profiling. In the last decade, novel NMR broadband homonuclear decoupling techniques through which multiplet signals collapse into single resonance lines-commonly called Pure Shift methods-have been developed to overcome the spectra resolution problem inherent to1 H NMR classical spectra. Here a step-by-step protocol of the plant extract preparation and the procedure to record optimal Pure Shift PSYCHE and SAPPHIRE-PSYCHE spectra in three different plant matrices-Vanilla plant leaves, potato tubers (S. tuberosum), and Cape gooseberries (P. peruviana)-is presented. The effect of the gain in resolution in metabolic identification, correlation analysis and multivariate analyses, as compared against classical spectra, is discussed.

Instituciones: Pontificia Universidad Católica del Perú