Table 2.
Characteristic 1H NMR signals of metabolites identified in various solvent extracts of I. galbana (s—singlet; d—doublet; t—triplet; dd—doublet of doublets; m—multiplet; J—coupling constant).
| No. | Putative Metabolite | δH (ppm), Multiplicity, J (Hz) | HSQC (1H-13C) | Hex | EtOAc | EtOH | AqE | Aq | Reference |
|---|---|---|---|---|---|---|---|---|---|
| Amino acids | |||||||||
| 1. | Valine | 0.99 (d, 6.2) | 25.1 | - | - | + | + | + | [29] |
| 1.05 (d, 2.8) | 21.1 | ||||||||
| 2. | Isoleucine | 1.01 (d, 3.3) | 19.5 | - | - | + | + | + | [29] |
| 0.96 (t, 7.6) | - | ||||||||
| 3. | Leucine | 0.97 (d, 5.0) | 23.8 | + | + | + | + | + | [29] |
| 4. | Alanine | 3.74 (m) | 72.8 | - | - | + | + | + | [44] |
| 1.46 (d, 7.2) | 19.1 | ||||||||
| 5. | Threonine | 3.64 (dd, 5.7, 10.9) | 66.5 | - | - | - | - | + | [44] |
| 1.37 (d, 6.9) | - | ||||||||
| Carbohydrates/Others | |||||||||
| 6. | Sucrose | 5.37 (d, 4.1) | - | - | - | + | + | + | [45] |
| 4.22 (d, 2.5) | 76.5 | ||||||||
| 3.83 (m) | - | ||||||||
| 3.68 (s) | - | ||||||||
| 3.44 (t, 6.7) | 74.5 | ||||||||
| 7. | Glucose | 3.78 (m) | 72.8 | - | - | + | + | + | [45] |
| 3.52 (dd, 4.6, 8.4) | 66.5 | ||||||||
| 8. | Choline | 3.22 (s) | 57.0 | - | - | + | + | + | [29] |
| 9. | Dimethylsulphonio-propionate (DMSP) | 3.44 (t, 6.7) | 43.9 | - | - | + | + | + | [29] |
| 2.92 (s) | 28.3 | ||||||||
| 2.70 (t, 6.7) | 33.4 | ||||||||
| 10. | d-1,4/2,5-cyclohexa-netetrol | 3.72 (m) | 73.2 | - | - | + | + | + | [29] |
| 1.83 (m) | 37.3 | ||||||||
| Saturated fatty acids | |||||||||
| 11. | Palmitic acid | 2.35 (t, 7.6) | + | + | + | + | - | [45] | |
| 1.61 (m) | 27.9 | ||||||||
| 1.33 (m) | 33.2 | ||||||||
| 0.88 (t, 6.9) | 16.4 | ||||||||
| 12. | Arachidic acid | 2.35 (t, 7.6) | + | + | + | + | - | [45] | |
| 1.60 (m) | 27.9 | ||||||||
| 1.40 (m) | 18.2 | ||||||||
| 1.29 (m) | 32.2 | ||||||||
| 0.88 (t, 6.9) | 16.4 | ||||||||
| Unsaturated fatty acids | |||||||||
| 13. | Oleic acid | 5.34 (m) | 130.3 | + | + | + | + | - | [45] |
| 2.25 (t, 7.5) | 37.4 | ||||||||
| 2.02 (m) | 23.3 | ||||||||
| 1.27 (m) | 33.2 | ||||||||
| 0.87 (t, 6.9) | 16.4 | ||||||||
| 14. | α-linoleic acid | 5.34 (m) | - | + | + | + | + | - | [45] |
| 5.32 (m) | - | ||||||||
| 2.80 (m) | 29.1 | ||||||||
| 2.25 (t, 7.5) | 37.4 | ||||||||
| 2.02 (m) | - | ||||||||
| 1.27 (m) | - | ||||||||
| 0.96 (t, 7.6) | 16.6 | ||||||||
| 15. | Docosahexaenoic fatty acid chain (DHA) | 5.30–5.38 (m) | 130.3 | + | + | + | + | - | HMDB |
| 2.38 (m) | 36.8 | ||||||||
| 2.06 (m) | 29.7 | ||||||||
| 0.96 (t, 7.6) | 16.6 | ||||||||
| 16. | Docosapentaenoic fatty acid chain (DPA) | 5.30–5.38 (m) | 131.8 | + | + | + | + | - | HMDB |
| 2.33 (m) | 36.9 | ||||||||
| 1.38 (m) | 31.3 | ||||||||
| 1.30 (m) | 33.2 | ||||||||
| 0.87 (t, 6.9) | 32.0 | ||||||||
| 17. | Cholesterol | 5.28 (dd, 8.3, 17.6) | - | + | + | + | + | - | HMDB |
| 2.31 (dd, 2.8, 6.2) | - | ||||||||
| 1.61 (m) | - | ||||||||
| 0.82 (m) | 22.2 | ||||||||
| 0.77 (d, 6.6) | 25.0 | ||||||||
| 0.65 (m) | - | ||||||||
| Carotenoids | |||||||||
| 18. | Fucoxanthin | 6.77 (dd, 4.2, 4.2) | - | - | + | + | - | - | [29], HMDB |
| 6.41 (dd, 11.1, 22.2) | - | ||||||||
| 2.59 (d, 18.5) | - | ||||||||
| 2.12 (s) | - | ||||||||
| 2.09 (s) | - | ||||||||
| 1.97 (s) | - | ||||||||
| 1.58 (dd, 7.2, 13.7) | - | ||||||||
| 1.37 (dd, 5.7, 9.7) | 31.3 | ||||||||
| 1.19 (s) | 23.1 | ||||||||
| 1.08 (s) | 34.7 | ||||||||
| 1.01 (s) | 26.9 | ||||||||
| 19. | Astaxanthin | 6.77 (m) | - | + | + | + | - | - | [45], HMDB |
| 6.61 (d, 3.8) | - | ||||||||
| 6.63 (d, 3.2) | - | ||||||||
| 4.15 (dd) | 65.2 | ||||||||
| 2.12 (s) | - | ||||||||
| 1.91 (s) | 13.8 | ||||||||
| 1.19 (s) | 23.1 | ||||||||
| Chlorophylls | |||||||||
| 20. | Pheophytin a | 9.21 (s) | 107.2 | + | + | + | - | - | [46], PubChem |
| 9.00 (s) | 99.9 | ||||||||
| 8.60 (s) | 96.2 | ||||||||
| Alkenone | |||||||||
| 21. | Polyunsaturated long-chain alkenones (PULCAs) | 2.12 (s) | - | + | + | + | - | - | [46], PubChem |
| 1.95 (m) | 35.4 | ||||||||
Positive (+) and negative (-) signs denote present and absent, respectively; Ref. = Reference.