Development of a NMR-based analytical method for polar metabolomics studies in industrial and food crops

Metabolomics has emerged as an important ally in understanding the biochemical and molecular mechanism of industrial and food crops in response to abiotic stresses, such as drought, salinity, and temperature fluctuations. This is crucial for developing stress-resistant plant varieties through targeted breeding and genetic engineering. Herein, this study describes the development of a NMR-based analytical method for polar metabolomics studies in industrial and food crops. The development of the analytical method included the assessment of the effect of lipoprotein removal by chemical delipidization and by chemical precipitation, using two different pulse sequences, and four different number of scans during acquisition. ¹H NMR spectra for the calibration curves were acquired for eight points with concentrations ranging from 0.00 to 10000 μM. The method's robustness was assessed by its linearity, precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ). Taken together, the ideal condition for probing the polar metabolomics encompassed delipidization with hexane prior to extraction in deuterated water (D₂O) and the use of the Carr-Purcell-Meiboom-Gill pulse sequence with 32 scans. Furthermore, the validated method was applied to different tissues of Triticum spp., Ricinus communis, and Glycine max growing under normal and stress conditions. The PLS-DA analysis showed that the validated method could differentiate G. max, R. communis, and T. spp different tissue metabolomes, whereas it was also possible to efficiently differentiate R. communis roots and endosperm subjected to normal and stress conditions. Ultimately, the validated method might enhance crop resilience and improve agricultural sustainability in changing climates.