Table 1. Possible identities of metabolites measured in negative ionization mode.
Potential metabolites identified by comparing m/z ratios of metabolites with m/z ratios obtained from the human metabolome (HMDB) database and also taking expected natural occurrence into consideration.
| Metabolite m/z (Da) | HMDB m/z (Da) | m/z error (Da) | Ret. Time (s) | Possible identity |
|---|---|---|---|---|
| 204.0657 | 204.0666 | 0.0009 | 198 | Cinnamoylglycine/Indolelactic acid/3-Indolehydracrylic acid/5-Methoxyindoleacetate [M–H] |
| 160.0757 | n/a | n/a | 198 | Fragment of 204.0657 [M–CO2] |
| 217.1071 | 217.1082 | 0.0011 | 212 | 2-Hydroxydecanedioic acid/3-Hydroxydecanedioic acid [M–H] |
| 243.1234 | 243.1167 | 0.0067 | 214 | Isoleucyl-hydroxyproline/hydroxyprolyl-leucine [M–H] |
| 199.0972 | 199.0976 | 0.0004 | 224 | acis-4-Decenedioic acid/cis-5-Decenedioic acid [M–H] |
| 181.0873 | n/a | n/a | 224 | Fragment of 199.0972 [M–H2O–H] |
| 201.1129 | 201.1132 | 0.0003 | 233 | aSebacic acid/Heptylmalonic acid/3-Methylazelaic acid [M–H] |
| 316.1229 | 316.1303 | 0.0074 | 234 | Tryptophyl-Hydroxyproline/Hydroxyprolyl-Tryptophan [M–H] |
Notes.
Ret. Time, Retention time.
a
Also detected in positive mode.