Metabolic discrimination of sucrose starvation from Arabidopsis cell suspension by 1 H NMR based metabolomics

Whole cell extracts of Arabidopsis cell cultures maintained on various sucrose concentrations (0,3, and 6%) were analyzed by 1 H NMR spectroscopy to determine the comprehensive metabolic change in these cultures during sucrose starvation. The amount of sucrose, glucose, and fructose in the cells decreased to almost nothing after 12 h of culture in medium without sucrose. In contrast, the total free amino acid content of the cells increased as the culture proceeded. Among the free amino acids, phenylalanine and malic acid increased the most, followed by asparagine and alanine, whereas glutamic acid did not change significantly. These results are in agreement with previous studies using HPLC. 1 H NMR spectroscopy enabled measurement of changes in the sugar and free amino acid content of whole cell extracts without fractionation and complicated sample preparation. These results indicate that comprehensive metabolic changes in the cells can be determined by a simple, rapid method using whole cell extracts and 1 H NMR spectroscopy.