11.11.2020

PSYCHE - A Valuable Experiment in Plant NMR-Metabolomics.

IPB researchers together with colleagues from IPK Gatersleben recently examined different NMR methods to enhance the metabolomic analysis of biological samples. The high complexity of plant extracts causes signal overlap in NMR spectra and renders their evaluation challenging. In recent years, NMR Pure Shift methods have emerged that improve spectral resolution by suppressing homonuclear coupling. As a result, multiplet signals in NMR spectra appear as singlets leading to less overlap. Still, whether Pure Shift is suitable for highly diverse samples such as plant extracts has been as yet unclear.

In the present study, the researchers tested two Pure Shift decoupling methods, PSYCHE and Zangger-Sterk. After a first test with single plant metabolite compounds in which PSYCHE proved superior, they optimized the parameters of this method in order to, e.g., reduce artifact signals. Next, the researchers applied PSYCHE to the metabolomics analysis of extracts of 21 Hypericum species. In comparison to conventional ¹H-NMR, PSYCHE yielded similar results in detailed binning and multivariate data analysis. While the current PSYCHE methods might not be able to outperform conventional ¹H-NMR in complex metabolomics analyses, the researchers point out that PSYCHE can provide important information for the interpretation of specific regions of overlapping spectral signals.

Original publication:
Stark P, Zab C, Porzel A, Franke K, Rizzo P, Wessjohann LA. PSYCHE-A Valuable Experiment in Plant NMR-Metabolomics. Molecules. 2020 Nov 4;25(21):E5125. doi: 10.3390/molecules25215125