TABLE 3.
Annotated VIP responsible for season discrimination in negative and positive ionization modes.
| Discrimination in the negative ESI mode | ||||||
|---|---|---|---|---|---|---|
| Rt | Molecular Formula | Adduct | Theoretical m/z | Experimental m/z | Error (ppm) | Annotated compound (chemical class) |
| 0.75 | C5H8O5 | [M-H + H2O]− | 165.04112 | 165.03981 | 7.93 | D-(+)-Ribonic acid γ lactone (monossacharide) |
| 0.75 | C6H12O6 | [M-H]− | 179.05611 | 179.05536 | 4.19 | Inositol (Sugar alcohol) |
| 12.98 | C18H30O4 | [M-H]− | 309.20713 | 309.20790 | −2.49 | trans-Ekode-(E)-Ib (Fatty acid) |
| Discrimination in the positive ESI mode | ||||||
| 0.83 | C7H13NO4 | [M + H]+ | 176.09173 | 176.09176 | -0.17 | N-Carboxyethyl γ aminobutyric acid (amino acid) |
| 10.67 | C18H34O5 | [M + NH4]+ | 348.27389 | 348.27374 | -1.18 | (Z)-5,8,11-trihydroxyoctadec-9-enoic acid (Fatty acid) |