TABLE 2.
Metabolites from the red meat metabolomics score that were positively associated with red meat consumption in both the EPIC-Norfolk and the randomized crossover trial1
| Name | Formula | Fold-change2 | P value | Chromatographic method3 | Retention time, min | Confidence level of identification4 | MS fragments for identification | Rank5 |
|---|---|---|---|---|---|---|---|---|
| 1-(1-Enyl-stearoyl)-2-arachidonoyl-GPE (P-18:0/20:4) | C43H78NO7P | 2.52 | 1.36 × 10−6 | RP | 9.04, 9.43 | Level 2 | 361.2741 | 1 |
| 611.5296 | ||||||||
| 392.2934 | ||||||||
| 1-(1-Enyl-stearoyl)-2-arachidonoyl-GPC (P-18:0/20:4) | C46H84NO7P | 2.00 | 6.69 × 10−6 | RP | 9.1 | Level 3 | 184.0733 | 2 |
| 4-Hydroxyproline | C5H9NO3 | 6.27 | 1.06 × 10−4 | HILIC | 5.74 | Level 1 | 68.0498 | 4 |
| 86.0601 | ||||||||
| TMAO | C3H9NO | 1.56 | 6.30 × 10−3 | HILIC | 3.62 | Level 1 | 42.0329 | 7 |
| 1-(1-Enyl-palmitoyl)-2-linoleoyl-GPC (P-16:0/18:2) | C42H80NO7P | 1.32 | 1.94 × 10−4 | RP | 8.97 | Level 3 | 184.0733 | 8 |
| 1-Palmityl-GPC (O-16:0) | C24H52NO6P | 2.01 | 3.64 × 10−6 | RP | 7.18 | Level 2 | 104.1072 | 9 |
| 184.0770 | ||||||||
| 341.3025 | ||||||||
| Creatine | C4H9N3O2 | 1.50 | 4.88 × 10−2 | RP | 0.7 | Level 1 | 44.0482 | 13 |
| 90.0538 | ||||||||
| 1-Palmityl-2-arachidonoyl-GPC (O-16:0/20:4) | C44H82NO7P | 2.44 | 4.30 × 10−6 | RP | 9.04 | Level 3 | 184.0733 | 17 |
| 1-(1-Enyl-stearoyl)-2-linoleoyl-GPC (P-18:0/18:2) | C44H84NO7P | 1.96 | 1.00 × 10−3 | RP | 9.19 | Level 3 | 184.0733 | 18 |
| Deoxycarnitine | C7H15NO2 | 1.23 | 6.12 × 10−3 | HILIC | 5.18 | Level 2 | 43.0179 | 21 |
| 60.0811 | ||||||||
| 87.0445 | ||||||||
| Stearoylcarnitine | C25H49NO4 | 1.52 | 7.36 × 10−3 | RP | 6.47 | Level 1 | 85.0277 | 57 |
| 60.0813 |
EPIC-Norfolk, European Prospective Investigation into Cancer and Nutrition-Norfolk; GPC, glycerophosphocholine; GPE, glycerophosphoethanolamine; HILIC, hydrophilic interaction liquid chromatography; RP, reverse-phase chromatography.
Fold-change in signal intensity in the randomized controlled trial after fried pork intake compared with the tofu diet. Paired Welch's t tests were used to evaluate whether metabolites were significantly increased after pork intake compared with tofu intake. Supplemental Figure 3 shows the variation of metabolite intensity after consumption of pork compared with tofu.
Supplemental Figure 4 shows the chromatographic tracing of selected metabolites in the blood after consumption of pork compared with tofu.
Level of confidence in metabolite identification according to Sumner et al. (25): level 1, matching of mass, retention time, and mass fragmentation pattern with authentic chemical standard; level 2, matching of accurate mass and mass fragmentation pattern with the corresponding compound in a database; level 3, matching of mass and fragmentation pattern with the corresponding compound in a database—due to the nonspecific fragment, only the functional group, but not the length of each carbon chains can be determined.
Coefficient rank out of 139 metabolites in the red meat metabolite score in the EPIC-Norfolk study.