Table 2.
GC-EI-MS relevant peaks in the chromatograms of the labdanum absolutes and fractions extracted (Figures S1–S4), relative quantification in relation to the major peak area (+: 2–10%; ++: 10–50%; +++: 50–90%; M: 90–100%), tentative identification based on Kovats retention index (RI) and fragmentation m/z- ions pattern compared to NIST database (Match), and identification using standards (grey).
| Experimental | NIST Library/Standard Identification | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Peak | RT (min) | RI (i.u.) | Extract | TMS (73) | NIST Match | Compound | NIST RI | |||
| Adl Fractions | ||||||||||
| Adl | Zam | Flv | Dit | |||||||
| 1 | 7.46 ± 0.02 | 1133 ± 1 | + | yes | 886 ± 48 | 3-acetoxy-3-hydroxypropionic acid, methyl ester | ||||
| 2 | 9.64 ± 0.03 | 1286 ± 2 | + | ++ | yes | 921 ± 48 | 3-phenylpropanoic acid (hydrocinnamic acid), TMS | 1279/1246 | ||
| 3 | 9.72 ± 0.02 | 1291 ± 1 | ++ | yes | 814 ± 78 | 3-methyl-hexanedioic acid, dimethyl ester | 1285/1253 | |||
| 4 | 10.37 ± 0.00 | 1341 ± 0 | + | - | ||||||
| 5 | 12.42 ± 0.10 | 1499 ± 8 | ++ | - | ||||||
| 6 | 13.36 ± 0.02 | 1571 ± 2 | ++ | 872 ± 15 | 4-hydroxy-α-methyl-benzenepropanol (rhododendrol) | 1585 | ||||
| 7 | 14.20 ± 0.07 | 1630 ± 4 | ++ | - | ||||||
| 8 | 14.98 ± 0.13 | 1681 ± 8 | +++ | yes | - | |||||
| 9 | 16.02 ± 0.28 | 1742 ± 16 | M | yes | - | |||||
| 10 | 18.58 ± 0.02 | 1875 ± 1 | + | yes | - | |||||
| 11 | 19.80 ± 0.03 | 1932 ± 1 | ++ | yes | 885 ± 18 | Hexadecanoic acid, methyl ester | 1926/1909 | |||
| 12 | 24.58 ± 0.04 | 2135 ± 2 | ++ | + | + | yes | 884 ± 40 | Octadecanoic acid, methyl ester | 2128/2110 | |
| 13 | 26.48 ± 0.02 | 2212 ± 1 | ++ | yes | - | |||||
| 14 | 26.59 ± 0.04 | 2216 ± 1 | + | - | ||||||
| 15 | 26.81 ± 0.04 | 2225 ± 2 | + | - | ||||||
| 16 | 27.00 ± 0.04 | 2233 ± 2 | M | ++ | + | + | yes | 862 ± 32 | Labd-8(20)-en-15-oic acid, methyl ester | |
| 17 | 27.21 ± 0.05 | 2242 ± 2 | +++ | ++ | + | yes | - | |||
| 18 | 27.51 ± 0.04 | 2254 ± 2 | + | - | - | |||||
| 19 | 27.91 ± 0.05 | 2269 ± 2 | +++ | ++ | + | + | yes | - | ||
| 20 | 29.65 ± 0.04 | 2339 ± 1 | ++ | + | + | yes | 837 ± 56 | Eicosanoic acid, methyl ester | 2329/2310 | |
| 22 | 31.08 ± 0.01 | 2395 ± 0 | + | + | M | yes | Labdanolic acid, TMS (standard) | |||
| 23 | 32.87 ± 0.04 | 2467 ± 1 | ++ | ++ | + | ++ | yes | 6-oxo-labd-7-en-15-oic acid/6-oxocativic acid, TMS (standard) | ||
| 24 | 33.46 ± 0.01 | 2492 ± 0 | + | yes | - | |||||
| 25 | 33.83 ± 0.01 | 2506 ± 0 | + | - | ||||||
| 26 | 34.11 ± 0.00 | 2515 ± 0 | + | yes | - | |||||
| 27 | 34.49 ± 0.05 | 2528 ± 2 | + | + | yes | - | ||||
| 28 | 34.62 ± 0.05 | 2532 ± 2 | + | yes | 884 ± 1 | Docosanoic acid, methyl ester | ||||
| 29 | 38.39 ± 0.03 | 2696 ± 2 | + | yes | - | - | ||||
| 30 | 38.97 ± 0.03 | 2723 ± 2 | ++ | yes | 826 ± 4 | Octadecanoic acid, 2,3-hydropropyl ester | ||||
| 31 | 39.99 ± 0.00 | 2767 ± 0 | + | - | ||||||
| 32 | 43.72 ± 0.00 | 2934 ± 0 | ++ | Apigenin-4′,7-dimethyl ether | ||||||
| 33 | 44.40 ± 0.06 | 2963 ± 0 | +++ | Kaempferol-4′,3,7-trimethyl ether (methyljaranol) | ||||||
| 34 | 45.40 ± 0.01 | * | + | Apigenin-4′-methyl ether (acacetin) | ||||||
| 35 | 45.66 ± 0.01 | * | ++ | Apigenin-7-methyl ether (genkawin) | ||||||
| 36 | 46.10 ± 0.03 | * | ++ | + | M | Kaempferol-3,7-dimethyl ether (Jaranol) | ||||
| 37 | 47.83 ± 0.01 | * | ++ | Apigenin | ||||||
Retention time (RT), experimental Kovats RI, and NIST Match presented as mean values ± standard deviation of all the extracts. Relative quantification based of the mean values of triplicates for each extract. * Retention time higher than for triacontane (C30).