Fig 4. O-PLS-DA score plots derived from ¹H-NMR spectra of extracts from Jerusalem artichoke tubers.

(A, C, E, G and I) O-PLS-DA score plots. (B, D, F, H and J) Coefficient plots. (A) and (B) 150 mM NaCl, 1 day. (C) and (D) 150 mM NaCl, 3 days. (E) and (F) 150 mM NaCl, 7 days. (G) and (H) 50 mM NaCl, 7 days. (I) and (J) 250 mM NaCl, 7 days. The color map shows the significance of metabolite variations between the two classes (♦ control and ■ salt-treated). Peaks in the positive direction indicate metabolites that are more abundant in the salt-treated group. Consequently, metabolites that are more abundant in the control group are presented as peaks in the negative direction.