Authentication of Citrus spp. Cold-Pressed Essential Oils by Their Oxygenated Heterocyclic Components
Abstract
:1. Introduction
2. Results and Discussions
2.1. Method Validation
2.2. Comparison of Citrus EO Coumarin and Furanocoumarin Content
2.3. Multivariate Analysis
3. Materials and Methods
3.1. Chemicals
3.2. Essential Oil Samples
3.3. UPLC-MS/MS Analyses
3.4. Method Validation
3.5. Multivariate Analysis
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
AHC | agglomerative hierarchical cluster analysis |
DAD | diode array detector |
ELISA | enzyme-linked immunosorbent assay |
EO | essential oil |
FC | furanocoumarin |
GC-MS | gas chromatography–mass spectroscopy |
HPLC | high-performance liquid chromatography |
LC-MS | liquid chromatography- mass spectrometry |
LOQ | limit of quantification |
MRM | multiple reaction monitoring mode |
NMR | nuclear magnetic resonance |
OTUs | operational taxonomic units |
PCA | Principal component analysis |
ppm | parts per million |
QC | quality control |
RP-HPLC | reversed-phase-high-performance liquid chromatography |
UPGMA | unweighted pair group method with arithmetic average |
UPLC-MS/MS | ultra-performance liquid chromatography-tandem mass spectrometry |
References
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Compound | Linearity | LOQ (ppm) | Accuracy | Precision | Intermediate Precision | ||
---|---|---|---|---|---|---|---|
Linear Range (ppm) | Equation | r2 | Recovery % | RSD% | RSD% | ||
Coumarins | |||||||
Citropten | 0.001–0.1 | Y = 0.9847x + 0.0012 | 0.9991 | 0.001 | 98.92–113.80 | 2.60 | 4.44 |
5-Geranyloxy-7-methoxycoumarin | 0.0001–0.1 | Y = 0.9976x + 0.0002 | 0.9989 | 0.0001 | 94.07–105.44 | 2.23 | 2.05 |
Toncarine | 0.005–0.1 | Y = 0.9961x + 0.0003 | 0.9991 | 0.005 | 97.50–114.53 | 1.28 | 2.44 |
Herniarin | 0.001–0.1 | Y = 0.989x + 0.0008 | 0.9996 | 0.001 | 98.25–113.40 | 2.33 | 4.90 |
Linear furanocoumarins | |||||||
6’,7’-Epoxybergamottin | 0.001–0.1 | Y = 0.9948x + 0.0004 | 0.9990 | 0.001 | 96.83–109.00 | 2.29 | 1.05 |
Bergamottin | 0.001–0.1 | Y = 0.9975x + 0.0002 | 0.9988 | 0.001 | 95.75–104.56 | 2.26 | 3.05 |
Bergapten | 0.0001–0.1 | Y = 0.9956x + 0.0003 | 0.9994 | 0.0001 | 96.92–109.33 | 2.50 | 0.46 |
Biacangelicol | 0.001–0.1 | Y = 0.9923x + 0.0006 | 0.9992 | 0.001 | 97.17–107.27 | 2.18 | 2.32 |
Imperatorin | 0.001–0.1 | Y = 0.9904x + 0.0007 | 0.9997 | 0.001 | 96.40–106.67 | 2.59 | 2.32 |
Isopimpinellin | 0.0001–0.1 | Y = 1.0002x + 8x10-6 | 0.9989 | 0.0001 | 95.75–112.13 | 2.89 | 2.26 |
Oxypeucedanin | 0.005–0.1 | Y = 0.9946x + 0.0004 | 0.9987 | 0.005 | 96.33–107.73 | 2.62 | 1.17 |
Psoralen | 0.001–0.1 | Y = 0.9936x + 0.0005 | 0.9985 | 0.001 | 97.00–113.00 | 2.38 | 2.94 |
Trioxsalen | 0.001–0.1 | Y = 0.993x + 0.0005 | 0.9997 | 0.001 | 98.50–106.11 | 2.18 | 2.06 |
Xanthotoxin | 0.001–0.1 | Y = 0.9874x + 0.001 | 0.9997 | 0.001 | 98.58–112.07 | 3.67 | 2.54 |
Citrus Oil | Total Coumarin (ppm) | Total FC (ppm) | Coumarin Distribution |
---|---|---|---|
Bergamot (Brazil) | 52,473.90 ± 1775.63 | 48,798.90 ± 174.98 | Bergamottin > imperatorin > bergapten > 5-geranyloxy-7-methoxycoumarin > citropten > xanthotoxin > 6’,7’-epoxybergamottin > herniarin > psoralen > oxypeucedanin > isopimpinellin > biacangelicol |
Bergamot (Italy) | 171,453.11 ± 9227.11 | 167,281.60 ± 1017.74 | Bergamottin > imperatorin > 6’,7’-epoxybergamottin > 5-geranyloxy-7-methoxycoumarin > citropten > xanthotoxin > bergapten > herniarin > oxypeucedanin > isopimpinellin > psoralen > biacangelicol |
Bitter Orange | 814.95 ± 9.52 | 809.21 ± 1.30 | 6’,7’-Epoxybergamottin > xanthotoxin > bergapten > imperatorin > bergamottin > citropten > psoralen > 5-geranyloxy-7-methoxycoumarin > herniarin > isopimpinellin |
Calamansi | 0.15 ± 0.02 | 0 | 5-Geranyloxy-7-methoxycoumarin |
Clementine (Brazil) | 75.26 ± 0.08 | 43.03 ± 0.11 | 5-Geranyloxy-7-methoxycoumarin > bergamottin > imperatorin > citropten > oxypeucedanin > xanthotoxin > bergapten > herniarin > isopimpinellin |
Clementine (Italy) | 4.69 ± 0.03 | 3.38 ± 0.04 | Oxypeucedanin > bergamottin > citropten > xanthotoxin > biacangelicol > bergapten > 5-geranyloxy-7-methoxycoumarin > psoralen |
Grapefruit (Red) | 13,099.29 ± 207.97 | 13,013.55 ± 22.87 | 6’,7’-Epoxybergamottin > bergamottin > imperatorin > oxypeucedanin > biacangelicol > xanthotoxin > bergapten > 5-geranyloxy-7-methoxycoumarin > citropten > isopimpinellin > psoralen > herniarin |
Grapefruit (White) | 9163.08 ± 229.85 | 9027.29 ± 25.14 | 6’,7’-Epoxybergamottin > imperatorin > bergamottin > oxypeucedanin > biacangelicol > xanthotoxin > psoralen > bergapten > herniarin > 5-geranyloxy-7-methoxycoumarin > isopimpinellin > citropten |
Kaffir Lime | 75.46 ± 5.13 | 43.15 ± 0.38 | Imperatorin > citropten > bergamottin > 5-geranyloxy-7-methoxycoumarin > xanthotoxin > bergapten > oxypeucedanin > herniarin > isopimpinellin > psoralen |
Kumquat | 169.65 ± 0.72 | 93.19 ± 0.53 | Bergamottin > 5-geranyloxy-7-methoxycoumarin > imperatorin > citropten > xanthotoxin > bergapten > oxypeucedanin > herniarin > isopimpinellin > 6′,7′-epoxybergamottin > biacangelicol |
Lemon (Argentina) | 5404.76 ± 3.60 | 3861.29 ± 3.41 | Imperatorin > bergamottin > citropten > oxypeucedanin > 5-geranyloxy-7-methoxycoumarin > biacangelicol > 6′,7′-epoxybergamottin > herniarin > xanthotoxin > bergapten > isopimpinellin |
Lemon (Brazil) | 3321.86 ± 1.84 | 2335.29 ± 1.77 | Imperatorin > bergamottin > citropten > 5-geranyloxy-7-methoxycoumarin > oxypeucedanin> biacangelicol > 6′,7′-epoxybergamottin > xanthotoxin > bergapten > herniarin > isopimpinellin |
Lemon (Germany) | 3107.99 ± 3.27 | 2029.93 ± 2.61 | Imperatorin > bergamottin > 5-geranyloxy-7-methoxycoumarin > citropten > oxypeucedanin > 6′,7′-epoxybergamottin > biacangelicol > herniarin > xanthotoxin > bergapten > isopimpinellin |
Lemon (Italy) | 10,874.88 ± 8.28 | 8346.28 ± 9.30 | Bergamottin > imperatorin > oxypeucedanin > 5-geranyloxy-7-methoxycoumarin > citropten > biacangelicol > 6′,7′-epoxybergamottin > xanthotoxin > bergapten > herniarin > isopimpinellin > psoralen |
Lemon (South Africa) | 4268.48 ± 2.13 | 3185.78 ± 2.81 | Oxypeucedanin > imperatorin > bergamottin > citropten > 5-geranyloxy-7-methoxycoumarin > biacangelicol > 6′,7′-epoxybergamottin > xanthotoxin > bergapten > herniarin > isopimpinellin |
Lemon (Spain) | 3343.46 ± 4.76 | 2467.31 ± 4.28 | Imperatorin > bergamottin > 5-geranyloxy-7-methoxycoumarin > citropten > oxypeucedanin > 6′,7′-epoxybergamottin > biacangelicol > xanthotoxin > bergapten > herniarin > isopimpinellin |
Lemon (USA) | 2717.40 ± 4.45 | 1985.52 ± 4.93 | Imperatorin > bergamottin > citropten > 5-geranyloxy-7-methoxycoumarin > oxypeucedanin > biacangelicol > 6′,7′-epoxybergamottin > xanthotoxin > bergapten > herniarin > isopimpinellin > psoralen |
Lime | 23,795.43 ± 564.22 | 16,725.07 ± 43.80 | Bergamottin > imperatorin > 5-geranyloxy-7-methoxycoumarin > citropten > oxypeucedanin > xanthotoxin > herniarin > bergapten > isopimpinellin > 6′,7′-epoxybergamottin > biacangelicol > psoralen |
Mandarin (Green) | 32.27 ± 0.35 | 22.77 ± 0.46 | Imperatorin > bergamottin > 5-geranyloxy-7-methoxycoumarin > citropten > xanthotoxin > oxypeucedanin > herniarin > bergapten > isopimpinellin > biacangelicol |
Mandarin (Red) | 27.42 ± 0.06 | 19.06 ± 0.08 | Imperatorin > bergamottin > 5-geranyloxy-7-methoxycoumarin > citropten > oxypeucedanin > xanthotoxin > bergapten > herniarin > isopimpinellin > biacangelicol |
Mandarin (Yellow) | 52.89 ± 0.04 | 37.96 ± 0.05 | Imperatorin > bergamottin > 5-geranyloxy-7-methoxycoumarin > citropten > xanthotoxin > bergapten > herniarin > oxypeucedanin > isopimpinellin > biacangelicol |
Petitgrain (Lemon) | 36.22 ± 2.10 | 20.74 ± 0.18 | Herniarin > imperatorin > citropten > bergapten > xanthotoxin > bergamottin > psoralen > 5-geranyloxy-7-methoxycoumarin > oxypeucedanin > isopimpinellin > biacangelicol |
Petitgrain (Lime) | 58.93 ± 1.37 | 47.47 ± 0.11 | Imperatorin > xanthotoxin > citropten > bergapten > isopimpinellin > bergamottin > 5-geranyloxy-7-methoxycoumarin > herniarin > oxypeucedanin > psoralen |
Sweet Orange (Navel) | 179.26 ± 9.94 | 140.13 ± 0.75 | 6′,7′-Epoxybergamottin > bergamottin > oxypeucedanin > imperatorin > 5-geranyloxy-7-methoxycoumarin > citropten > biacangelicol > xanthotoxin > bergapten > isopimpinellin > herniarin > psoralen |
Sweet Orange (Valencia) | 122.27 ± 2.29 | 68.75 ± 0.19 | 5-Geranyloxy-7-methoxycoumarin > imperatorin > bergamottin > citropten > oxypeucedanin > xanthotoxin > bergapten > herniarin > isopimpinellin > 6′,7′-epoxybergamottin > biacangelicol |
Tangerine (Brazil) | 149.45 ± 1.58 | 94.31 ± 1.45 | Imperatorin > bergamottin > 5-geranyloxy-7-methoxycoumarin > citropten > xanthotoxin > bergapten > 6′,7′-epoxybergamottin > oxypeucedanin > herniarin > isopimpinellin > biacangelicol > psoralen |
Tangerine (Italy) | 2.44 ± 0.02 | 1.95 ± 0.03 | Bergamottin > bergapten > xanthotoxin > oxypeucedanin > citropten > 6′,7′-epoxybergamottin > 5-geranyloxy-7-methoxycoumarin |
Yuzu | 609.06 ± 0.33 | 597.1 ± 0.41 | 6′,7′-Epoxybegamottin > biacangelicol > oxypeucedanin > xanthotoxin > bergapten > imperatorin > citropten > bergamottin > herniarin > 5-Geranyloxy-7-methoxycoumarin > isopimpinellin |
Citrus Oil | Non-Volatile Components | Reported Amount | Reference(s) |
---|---|---|---|
Bitter orange | Bergapten Epoxybergamottin Psoralen | 0.035–0.073% 0.082% 0.007% | [3] |
Bergamot CP | 5-Geranloxy-7-methoxycoumarin 5-Methoxy-7-geranoxycoumarin Bergamottin Bergaptol Psoralen Bergapten Citropten | 0.08–0.68% 0.04–0.15% 0.68–2.75% 0–0.19% 0–0.0026% 0.11–0.33% 0.01–0.35% | [3] |
Lemon | 5-Geranloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Byakangelicol Bergapten Citropten Isopimpinellin oxypeucedanin | 0.18–0.28% 0.01–0.045% 0.16–0.54% 0.006–0.16% 0.0001–0.035% 0.05–0.17% 0–0.011% 0.09–0.82% | [3] |
Lime | 5-Geranloxy-7-methoxycoumarin 5-Geranoxy-8-methoxypsoralen 8-Geranyloxypsoralen 5-Methoxy-7-geranoxycoumarin Bergamottin Bergapten Citropten Isopimpinellin oxypeucedanin | 1.7–3.2% 0.2–0.9% 0.10–0.14% 1.7–5.2% 1.7–3.0% 0.17–0.33% 0.4–2.2% 0.1–1.3% 0.02–0.3% | [3] |
Grapefruit | Bergamottin Epoxybergamottin Bergapten | <0.11% 0.1126% 0.012–0.19% | [3] |
Mandarin | Bergamottin Bergapten | 0–0.001% 0–0.0003% | [3] |
Mandarin CO2 | Bergapten Citropten | 0.07% 0.76% | [20] |
Lemon (coastal) | Bergapten Citropten Herniarin Isopimpinellin | 0–10 ppm 700–1300 ppm 0–10 ppm 0–5 ppm | [21] |
Lemon (desert) | Bergapten Citropten Herniarin Isopimpinellin | 50–350 ppm 700–1700 ppm <10 ppm 35–110 ppm | [21] |
Lemon | 5-Geranoxy-7-methoxycoumarin 5-Isopent-2′-enyloxy-8-(2′,3′-epoxyisopentyloxypsoralen) 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Byakangelicol Citropten Isoimperatorin Oxypeucedanin Oxypeucedanin hydrate | 1800–2500 ppm 190–370 ppm tr 190–360 ppm 1600–1910 ppm 660–1230 ppm 520–1420 ppm tr 890–1570 ppm tr | [21] |
Lemon | 5-Geranoxy-7-methoxycoumarin 5-Isopent-2′-enyloxy-8-(2′,3′-epoxyisopentyloxypsoralen) 8-Geranyloxypsoralen Bergamottin Byakangelicol Citropten Oxypeucedanin | 2453–2845 ppm 204–324 ppm 399–454 ppm 2635–2973 ppm 555–1640 ppm 659–1495 ppm 863–2200 ppm | [22] |
Lime oil (Mexican type B) | 5-Geranoxy-7-methoxycoumarin 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Bergapten Byakangelicol Citropten Cnidicin Herniarin Imperatorin Isoimperatorin Isopimpinellin Oxypeucedanin Oxypeucedanin hydrate | 27,770–45,350 ppm 2100–2790 ppm 3800–4540 ppm 25,320–41,590 ppm 2160–3920 ppm 80–1020 ppm 5940–10,950 ppm 70–250 ppm 3350–4670 ppm 380–660 ppm 70–410 ppm 3010–7300 ppm 6660–10,720 ppm 1620–1710 ppm | [23] |
Lime (type A) | 5-Geranoxy-7-methoxycoumarin 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Bergapten Byakangelicol Citropten Cnidicin Herniarin Imperatorin Isopimpinellin Oxypeucedanin Oxypeucedanin hydrate | 41,550–63,320 ppm 4170–4830 ppm 6520–8100 ppm 37,300–56,130 ppm 2000–3450 ppm 0–90 ppm 7350–11,740 ppm 90–340 ppm 1460–2970 ppm 830–900 ppm 5670–10,210 ppm 0–260 ppm 780–1160 ppm | [23] |
Key lime CP | 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Bergapten Byakangelicol Citropten Cnidicin Cnidilin Herniarin Imperatorin Isoimperatorin Isopimpinellin Oxypeucedanin Oxypeucedanin hydrate | 2790 ± 15 ppm 4470 ± 28.7 ppm 36,401 ± 150.9 ppm 3000 ± 31.1 ppm 92 ± 9.9 ppm 10,950 ± 92.8 ppm 250 ± 62 ppm 249 ± 7.6 ppm 3880 ± 45.8 ppm 39 ± 10.3 ppm 88 ± 5.9 ppm 7300 ± 46.9 ppm 10,600 ± 85.1 ppm 1690 ± 203 ppm | [24] |
Key Lime (type A) | 5-Geranoxy-7-methoxycoumarin 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Bergapten Citropten Cnidilin Herniarin Isoimperatorin Isopimpinellin Oxypeucedanin hydrate Xanthotoxin | 306.5–404.5 ppm <0.1 ppm <0.1 ppm 315.7–328.3 ppm 10–12.4 ppm 49.1–63.2 ppm 2.5–3.5 ppm 8.6–9.6 ppm <0.1 ppm 35–36.5 ppm <0.1 ppm <0.1 ppm | [25] |
Key Lime (type A) | 5-Geranoxy-7-methoxycoumarin 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Bergapten Citropten Cnidilin Herniarin Isoimperatorin Isopimpinellin Oxypeucedanin Oxypeucedanin hydrate Xanthotoxin | 409.3 ppm <0.1 ppm <0.1 ppm 315.4 ppm 8.9 ppm 48.4 ppm 2.4 ppm 7.4 ppm <0.1 ppm 33.1 ppm 14.4 ppm <0.1 ppm <0.1 ppm | [25] |
Persian Lime | 5-Geranoxy-7-methoxycoumarin 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Bergapten Citropten Cnidilin Herniarin Isoimperatorin Isopimpinellin Oxypeucedanin Oxypeucedanin hydrate Xanthotoxin | 194.3–378 ppm <0.1 ppm <0.1 ppm 222.1–391.8 ppm 15.8–25 ppm 32.6–56.9 ppm 0.5–0.8 ppm 33.9–59.4 ppm <0.1 ppm 16.9–29.3 ppm 21–32.8 ppm <0.1 ppm <0.1 ppm | [25] |
Bergamot oil (Italian) | 5-Geranoxy-7-methoxycoumarin Bergamottin Bergapten Citropten | 0.14–0.18% 1.37–1.6% 0.18–0.21% 0.18–0.26% | [25] |
Bergamot CP | 5-Geranoxy-7-methoxycoumarin Bergamottin Bergapten Citropten | 8–27 ppm 100–275 ppm 10–32 ppm 12–35 ppm | [25] |
Bergamot oil (commercial) | 5-Geranoxy-7-methoxycoumarin 5-Geranyloxy-8-methoxypsoralen 5-Isopentenyl-8-(2′,3′-dihydroxyisopentyloxy)psoralen 5-Isopentenyloxy-7-methoxycoumarin 8-Geranyloxypsoralen Bergamottin Bergapten Citropten Herniarin Isopimpinellin Oxypeucedanin | 18–37 ppm <5 ppm <5 ppm <5 ppm <5 ppm 68–116 ppm 4–10 ppm 10–13 ppm <5 ppm <5 ppm <5 ppm | [25] |
Bergamot oil | Bergamottin Bergapten Citropten | 96.7 ug/100mg 152.5 ug/100mg 21.7 ug/100mg | [26] |
Bergamot | Bergamottin Bergapten Epoxybergamottin Oxypeucedanin | 16,312 ppm 8 ppm 70.3 ppm 53.5 ppm | [12] |
Bergamot | 5-Geranoxy-7-methoxycoumarin Bergamottin Bergapten Citropten | 0.08–0.104% 1.097–1.409% 0.138–0.209% 0.134–0.212% | [27] |
Bergamot | 5-Geranoxy-7-methoxycoumarin Bergamottin Bergapten Citropten Herniarin | 0–2.827 ppm 0–39.203 ppm 0–4.215 ppm 0–6.134 ppm 0–0.251 ppm | [28] |
Bergamot | Bergapten Citropten | 1.70% 0.40% | [29] |
Bergamot | 5-Geranoxy-7-methoxycoumarin Bergamottin Bergapten Citropten | 0–3 ppm 0–37 ppm 0–268 ppm 0–14 ppm | [30] |
Bergamot | 5-Geranoxy-7-methoxycoumarin Bergamottin Bergapten Citropten Herniarin | 1065 ± 7.5 ppm 19,605 ± 73.2 ppm 2474 ± 28.4 ppm 2232 ± 26.3 ppm 67 ± 3.2 ppm | [24] |
Bergamot | Bergamottin Bergapten Citropten | 1.14–2.73% 0.06–0.4% 0.1–0.3% | [25] |
Citrus Oil | Scientific Name | No. of Samples | Origin |
---|---|---|---|
Calamansi | Citrus × microcarpa (Bunge) Wijnands | 5 | Philippines |
Tangerine | Citrus tangerina Hort. Ex Tanaka | 13 | Brazil |
Kumquat | Citrus japonica Thunb | 3 | Brazil |
Mandarin | Citrus reticulata Blanco | 33 | Brazil |
Clementine | Citrus clementina Hort. Ex Tanaka | 6 | Brazil |
Yuzu or Yuja | Citrus junos Sieb. Ex Tanaka | 16 | Brazil |
Bitter Orange | Citrus aurantium L. | 6 | Japan |
Sweet Orange | Citrus sinensis L. | 36 | Brazil |
Lime | Citrus aurantifolia (Christm.) Swingle | 28 | Brazil |
Bergamot | Citrus bergamia Risso & Poit | 66 | Italy and Brazil |
Grapefruit | Citrus × paradisi Macfady | 45 | South Africa and USA |
Lemon | Citrus limon Osbeck | 97 | Spain, Argentina, Brazil, Italy, USA, South Africa, and Germany |
Petitgrain | Citrus aurantifolia leaf and Citrus limon leaf | 20 | Paraguay |
Name | Other Name(s) | CAS # | Precursor (m/z) | Product 1 (m/z) | Product 2 (m/z) | Product 3 (m/z) | RT (min) |
---|---|---|---|---|---|---|---|
Coumarins | |||||||
Citropten or Limettin | 5,7-dimethoxycoumarin | 487-06-9 | 206.90 | 192.10 | 149.10 | 121.15 | 7.61 |
5-Geranyloxy-7-methoxycoumarin | 7380-39-4 | 328.90 | 193.10 | 137.05 | 149.10 | 12.25 | |
Herniarin | 7-Methoxycoumarin | 531-59-9 | 176.90 | 121.05 | 78.10 | 77.10 | 6.58 |
Toncarine | 6-Methylcoumarin | 92-48-8 | 160.90 | 105.05 | 76.95 | 115.05 | 7.18 |
Linear furanocoumarins | |||||||
Xanthotoxin | 8-methoxypsoralen | 298-81-7 | 216.90 | 89.05 | 174.10 | 202.10 | 7.74 |
Bergamottin | 5-geranyloxypsoralen | 7380-40-7 | 339.00 | 203.00 | 147.05 | 91.15 | 12.09 |
Oxypeucedanin | 5-(2l,3l-epoxyisopentyloxy)psoralen | 26091-73-6 | 286.90 | 202.90 | 147.20 | 91.20 | 8.34 |
Biacangelicol or Byakangelicol | 5-methoxy-8-(2l,3l-epoxyisopentyloxy) psoralen | 26091-79-2 | 317.00 | 233.05 | 231.10 | 218.10 | 8.21 |
Psoralen | 66-97-7 | 186.90 | 131.10 | 77.10 | 115.10 | 6.98 | |
Isopimpinellin | 482-27-9 | 246.90 | 216.95 | 232.05 | 189.05 | 7.57 | |
Bergapten | 484-20-8 | 216.90 | 202.10 | 174.10 | 89.05 | 7.75 | |
Imperatorin | 8-isopentenyloxypsoralen | 482-44-0 | 202.90 | 91.15 | 91.15 | 65.10 | 12.09 |
Trioxsalen | 3902-71-4 | 229.00 | 115.15 | 142.20 | 128.10 | 9.62 | |
6′,7′-Epoxybergamottin | 206978-14-5 | 354.90 | 203.10 | 153.15 | 147.10 | 10.11 |
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Dosoky, N.S.; Satyal, P.; Setzer, W.N. Authentication of Citrus spp. Cold-Pressed Essential Oils by Their Oxygenated Heterocyclic Components. Molecules 2022, 27, 6277. https://doi.org/10.3390/molecules27196277
Dosoky NS, Satyal P, Setzer WN. Authentication of Citrus spp. Cold-Pressed Essential Oils by Their Oxygenated Heterocyclic Components. Molecules. 2022; 27(19):6277. https://doi.org/10.3390/molecules27196277
Chicago/Turabian StyleDosoky, Noura S., Prabodh Satyal, and William N. Setzer. 2022. "Authentication of Citrus spp. Cold-Pressed Essential Oils by Their Oxygenated Heterocyclic Components" Molecules 27, no. 19: 6277. https://doi.org/10.3390/molecules27196277