Compound 1HNMR spectra (ppm) VIP Compound 1HNMRspectra (ppm) VIP
L-lactic acid 4.28 1.948 Pyruvic acid 2.46 1.170
Fructose 4.02 1.276 Glutamine 2.45 1.206
L-Serine 3.96 1.274 L-glutamine 2.44 1.177
tyrosine 3.95 1.034 Succinate 2.39 1.569
L-Alanine 3.76 1.361 L-glutamic acid 2.32 1.642
L-Threonine 3.59 1.131 4-Aminobutyrate 2.28 1.532
Betaine 3.26 1.273 L-Valine 2.27 1.438
Choline 3.19 1.503 LDL 1.47 1.135
creatinine 3.1 1.059 Citric acid 2.53 1.859
creatine 3.06 1.829 Glutamic acid 2.12 1.125
Putrescine 3.04 2.206 Acetic acid 1.91 1.478
Aspartate 2.81 1.169 Acetate 1.9 1.166
Methionine 2.64 1.592 Ornithine 1.82 1.329
Biological significance of the potential biomarkers in the three groups
Table 3: The identified biomarkers in three groups.