TABLE I.
LC-MS characteristics of identified, 24-h variant plasma metabolites and key parameters characterizing temporal variation
| Identification | Mass (Da) | Retention time (min) | Analytical CV (%) | Elemental composition | Fragments | Oscillation range/ MESOR (%) | Peak time (dec·h) | p value |
|---|---|---|---|---|---|---|---|---|
| Octenoylcarnitine (C8:1) | 285.20 | 3.2 | 4.9 | C15H27NO4 | 286.202, 227.1197, 85.0229, 60.077 | 7.5 | 1.4 | .020 |
| Acetylcarnitine (C2:0) | 203.12 | .4 | 4.2 | C9H17NO4 | 204.124, 85.010, 60.064 | 94.4 | 4.9 | <.001 |
| Oleoylcarnitine (C18:1) | 425.36 | 6.3 | 9.7 | C25H47NO4 | 426.358, 85.032, 60.084 | 43.6 | 5.2 | .039 |
| Hexanoylcarnitine (C6:0) | 259.18 | 2.8 | 15.1 | C13H25NO4 | 260.181, 201.115, 183.010, 85.029, 60.080 | 98.8 | 5.4 | <.001 |
| Tetradenenoylcarnitine (C14:1) | 369.30 | 5.2 | 6.9 | C21H39NO4 | 370.296, 85.029, 60.082 | 70.8 | 5.5 | <.001 |
| Tetradecadienoylcarnitine (C14:2) | 367.28 | 4.9 | 11.2 | C21H37NO4 | 368.280, 85.023, 60.076 | 63.8 | 6.1 | .002 |
| Palmitoylcarnitine (C16:0) | 399.34 | 6.1 | 17.8 | C23H45NO4 | 400.343, 341.268, 85.029, 60.081 | 109.8 | 6.4 | <.001 |
| Stearoylcarnitine (C18:0) | 427.37 | 6.7 | 8.5 | C25H49NO4 | 428.375, 369.304, 85.030, 60.0811 | 45.6 | 6.5 | .019 |
| Tetradecanoylcarnitine (C14:0) | 371.31 | 5.6 | 12.8 | C21H41NO4 | 372.309, 313.235, 85.028, 60.081 | 146.0 | 6.6 | <.001 |
| Dodecanoylcarnitine (C12:0) | 343.28 | 5.0 | 10.3 | C19H37NO4 | 344.276, 285.201, 133.085, 85.027, 60.079 | 122.6 | 7.1 | <.001 |
| Bilirubin | 584.27 | 8.2 | 5.0 | C33H36N4O6 | 585.274, 568.243, 299.139, 285.123 | 51.2 | 7.1 | <.001 |
| Octanoylcarnitine (C8:0) | 287.21 | 3.6 | 7.4 | C15H29NO4 | 288.213, 85.027, 60.079 | 68.6 | 7.4 | .003 |
| Decanoylcarnitine (C10:0) | 315.25 | 4.3 | 9.1 | C17H33NO4 | 316.249, 85.029, 60.080 | 77.2 | 7.8 | <.001 |
| Cortisol | 362.22 | 3.7 | 8.1 | C21H30O5 | 363.209, 327.194, 121.063 | 194.6 | 8.4 | <.001 |
| Cortisone | 360.19 | 3.8 | 19.5 | C21H28O5 | 361.201, 301.118, 163.071, 105.068 | 143.0 | 8.6 | <.001 |
| LysoPC(18:4) | 515.31 | 5.5 | 3.0 | C25H46NO7P | 516.306, 184.976, 104.107, 86.095 | 9.8 | 14.1 | .020 |
| Propionylcarnitine (C3:0) | 217.14 | .5 | 3.3 | C10H19NO4 | 218.132, 100.986, 85.014, 60.076 | 28.3 | 14.3 | .009 |
| Methionine | 149.06 | .5 | 6.5 | C5H11NO2S | 150.057, 133.031, 104.054, 61.010, 56.050 | 20.2 | 15.3 | <.001 |
| Tyrosine | 181.08 | .5 | 10.3 | C9H11NO3 | 182.086, 165.051, 136.075, 123.042, 119.050, 91.054 | 28.4 | 15.5 | <.001 |
| LysoPE(16:0) | 453.29 | 5.9 | 2.3 | C21H44NO7P | 454.290, 313.295, 62.058 | 27.8 | 16.5 | .003 |
| Proline | 115.07 | .4 | 3.1 | C5H9NO2 | 116.067, 70.056 | 47.8 | 16.6 | <.001 |
| LysoPE(18:3) | 475.28 | 5.9 | 11.2 | C23H42NO7P | 476.276, 335.269 | 35.0 | 16.9 | .023 |
| Butyrylcarnitine (C4:0) | 231.16 | 1.9 | 9.9 | C11H21NO4 | 232.151, 85.026, 60.082 | 53.4 | 17.7 | <.001 |
| LysoPE(20:4) | 501.30 | 6.1 | 17.7 | C25H44NO7P | 502.294, 484.283, 361.274, 62.059 | 113.2 | 18.3 | <.001 |
| LysoPE(18:2) | 477.29 | 5.7 | 13.2 | C23H44NO7P | 478.292, 337.270 | 110.4 | 18.8 | <.001 |
| LysoPE(18:1) | 479.31 | 6.1 | 2.2 | C23H46NO7P | 480.309, 339.289, 62.060 | 132.0 | 19.1 | <.001 |
| Lysine | 146.11 | 6.8 | .1 | C6H14N2O2 | 147.113, 130.088, 84.082 | 7.8 | 19.1 | .014 |
| Phenylalanine | 165.09 | 1.8 | 2.6 | C9H11NO2 | 166.085, 120.081 | 18.6 | 19.3 | <.001 |
| LysoPC(18:2) | 519.34 | 5.7 | 2.5 | C26H50NO7P | 520.340, 184.073, 104.107, 86.096 | 44.6 | 19.6 | .001 |
| LysoPC(20:5) | 541.32 | 5.7 | 2.3 | C28H48NO7P | 542.324, 524.313, 184.073, 104.107, 86.097 | 23.7 | 19.8 | .04 |
| LysoPC(20:3) | 545.69 | 6.0 | 18.6 | C28H52NO7P | 546.354, 184.072, 104.107, 86.096 | 57.1 | 20.0 | .02 |
| LysoPC(18:3) | 517.32 | 5.4 | 5.9 | C26H48NO7P | 518.324, 184.071, 86.096 | 67.2 | 20.5 | .002 |
| Leucine | 131.10 | .5 | 3.9 | C6H13NO2 | 132.102, 86.098, 44.051 | 15.6 | 21.5 | .048 |
| LysoPC(20:1) or PC (18:1/2:0) | 549.39 | 6.7 | 8.9 | C28H56NO7P | 550.385, 184.070, 104.105, 86.098 | 26.0 | 23.1 | .020 |