Table 4.
Melanoma-derived metabolites 1 identified via targeted screening in negative ionization, and their corresponding detected parent ions, adducts and MS/MS fragments, theoretical and experimental m/z, ppm error, retention time (tR), isotopic ratio RSD (%), p value, Fold Change (FC) and reliability score.
| Name | Adducts | Theoretical m/z |
Experimental m/z |
ppm Error | tR (min) | Adducts | MS/MS | Isotopic Ratio RSD (%) |
p Value | FC | Trust Level |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Inosine | M-H | 267.0730 | 267.0731 | 0.21 | 1.16 | M+Cl, M+FA-H, 2M+FA-H, 2M-H | 134.93, 134.98, 135.04 | <30% | 7.95E−15 | 0.46 | 13.5 |
| Succinic acid | M-H | 117.0187 | 117.0196 | 7.69 | 1.11 | 99, 73 | <30% | 0.000302 | 4.04 | 5.5 | |
| Allantoic acid | 2M-H | 351.1010 | 351.1008 | −0.51 | 4.54 | 307.11 (pseudo) | <30% | 0.000339 | 0.67 | 4.5 | |
| Xanthosine | M-H | 283.0678 | 283.0678 | 0.00 | 1.50 | M+FA-H | <30% | 8.77E−06 | 2.02 | 4.5 | |
| Dihydroxyacetone | 2M-H | 179.0550 | 179.0561 | 6.14 | 0.82 | M+Cl | ND2 | 0.000297 | 32.96 | 4 | |
|
S-Adenosyl-
homocysteine |
M-H | 383.1138 | 383.1139 | 0.26 | 0.92 | <30% | 1.13E−08 | 36.60 | 2.5 | ||
| Xylulose | M+K-2H | 187.0003 | 187.0012 | 5.05 | 0.82 | <30% | 1.31E−05 | 2.39 | 2.5 | ||
| N2-Methyl guanosine |
M+K-2H | 334.0548 | 334.0553 | 1.64 | 3.29 | <30% | 0.000287 | 434068.2 | 2.5 | ||
| Xanthurenic acid | M+Na-2H | 226.0116 | 226.0122 | 2.65 | 0.84 | ND | 0.000459 | 0.83 | 2 | ||
| Glutamic acid | M-H | 146.0453 | 146.0460 | 4.79 | 0.76 | ND | 9.3E−07 | 5.81 | 2 | ||
| Acetoacetic acid | M+FA-H | 147.0300 | 147.0299 | −0.80 | 0.80 | ND | 2.67E−07 | 188.88 | 2 | ||
| N-Formyl methionine | M-H | 176.0381 | 176.0385 | 2.14 | 3.14 | ND | 0.00212 | 1.21 | 2 | ||
| Pseudouridine | M+FA-H | 289.0671 | 289.0674 | 1.04 | 0.95 | ND | 1.71E−05 | 0.62 | 2 |
1: AUC > 0.8, for metabolites in bold, 2: not detected.