Metabolites ra K1-K2 K1-C K2-C 1 3-Hydroxybutyrate: 1.20(d), 2.31(dd), 2.41(dd), 4.16(m) -0.861 -0.949 -0.780 2 Acetate ：1.92(s) -0.524 - - 3 Acetone : 2.23(s) -0.626 -0.865 -0.770 4 Alanine : 1.48(d) 0.583 0.883 0.905 5 Citrate : 2.53(d), 2.68(d) 0.931 0.843 - 6 Creatine : 3.04(s), 3.93(s) - 0.870 0.762 7 Formate : 8.46(s) 0.690 0.799 - 8 Glutamate: 2.14(m), 2.35(m), 3.78(t) 0.810 0.846 - 9 Glutamine : 2.14(m), 2.45(m), 3.78(t) 0.882 0.846 - 10 Glycine : 3.56(s) 0.681 0.739 - 11 Histidine : 7.09(s), 7.87(s) 0.906 0.901 - 12 Isoleucine : 0.94(t), 1.01(d) -0.673 - - 13 L1: CH3-(CH2)n-(LDL&VLDL): 0.87(br) -0.816 - - 14 L2: CH3-(CH2)n-(LDL&VLDL): 1.27(br) -0.629 - - 15 L4: Lipid, =CH-CH-CH=: 2.75(br) 0.924 0.817 - 16 Lactate : 1.33(d), 4.12(q) - - -0.681 17 Leucine : 0.96(d) -0.624 - - 18 Lysine : 1.71(m), 1.90(m), 3.01(m), 3.76(t) 0.766 0.902 0.843 19 myo-Inositol : 3.59(dd), 3.66(dd), 4.06(m) 0.887 0.869 - 20 OAG: O-acetyl glycoprotein signals: 2.08(s) 0.539 0.725 - 21 Phenylalanine : 7.32(m), 7.37(m), 7.42(m) 0.841 0.906 - 22 Phosphocholine : 3.22(s) 0.608 0.695 - 23 Tyrosine : 6.90(d), 7.19(d) 0.908 0.943 0.736 24 Valine : 0.99(d), 1.04(d) -0.661 - - 25 α-Glucose: 3.42(t), 3.54(dd), 3.71(t), 3.73(m), 3.84(m), 5.22(d) 0.783 0.842 - 26 β-Glcose: 3.24vc(dd), 3.41(t), 3.46(m), 3.49(t), 3.90(dd), 4.65(d) 0.849 0.854 -

aCorrelation coefficients: positive and negative signs indicate positive and negative correlation in the concentrations, respectively. The correlation coefficient │r│> 0.632 or 0.444 was used as the cutoff value for the statistical significance based on the discrimination significance at P = 0.05 and df (degree of freedom) =8 or 18; ‘‘-’’ means that the correlation coefficient│r│ is less than the cutoff value. bMultiplicity: s, singlet; d, doublet; t, triplet; q, quartet; dd, doublet of doublets; m, multiplet.

Table 2: OPLS-DA coefficients derived from the NMR data of metabolites present in serum samples obtained from different groups.