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Article

Comparison of Three Gas Chromatographic Methods—Identification of Terpenes and Terpenoids in Cannabis sativa L.

by
Lumír Ondřej Hanuš
Lumir Lab, Asana Bio Group Ltd., The Hadassah Medical Center, Hebrew University Biotechnology Park, Ein Kerem Campus, Jerusalem 91120, Israel
Appl. Sci. 2024, 14(15), 6476; https://doi.org/10.3390/app14156476
Submission received: 3 June 2024 / Revised: 22 July 2024 / Accepted: 22 July 2024 / Published: 25 July 2024
(This article belongs to the Section Chemical and Molecular Sciences)

Abstract

:
Terpenes and terpenoids content in cannabis plant was already studied in the past with three used methods. Since these works did not compare the content of these substances under the same conditions, we tried to make this comparison exactly. Three different gas chromatography/mass spectrometry (GS/MS) methods—hexane-based liquid extraction (Lis), static headspace extraction (HS), and headspace solid-phase microextraction (SPME)—were compared to identify volatile compounds in four different cannabis chemotypes—Green fields chemotype, Titan chemotype, Black Domina chemotype, and Neptune chemotype. The main compounds focused on were monoterpenes/monoterpenoids and sesquiterpenes/sesquiterpenoids. For a final evaluation of the comparison of the three methods of analysis, hexane extraction gives comparable results (which is advantageous for quantitative analysis), although the other two methods allowed the identification of more substances. This means that the same method should be used everywhere for the quantitative evaluation of constituents in cannabis.

1. Introduction

Today we know, without any doubt, that the presence of terpenes and terpenoids in the Cannabis sativa L. plant is important, not only from the biogenetical point of view but also from the medical perspective. These bioactive compounds play an important role concerning use of cannabis as a medicament. Unfortunately, to date, there is not enough knowledge concerning the importance of these compounds and their ratio with other bioactive compounds, mainly cannabinoids. At present, it is very important to clarify the importance of the compounds’ quantity, the content of compound types and their ratios, and to understand the medicinal power of this plant for the treatment of various diseases.
The biosynthesis of terpenes in cannabis is comprised of two different pathways [1,2,3]. The first pathway is the plastidial methylerythritol phosphate pathway [4], which starts with the pyruvate and glyceraldehyde-3-phosphate [5,6]. Through several steps, geranyl diphosphate is produced, which then interacts with olivetolic acid for cannabigerolic acid origination. Additionally, this pathway is also a precursor for monoterpene origination [7,8]. The second pathway is the cytosolic mevalonate pathway [9], which starts with acetoacetyl-CoA and, after several steps, forms farnesyl diphosphate, followed by sesquiterpenes formation.
Terpenes found in hemp are not unique to this plant, as they are also found in other plants. Many terpenes have medical potential, but their bioactivity obviously depends on the cannabis chemotype, due to terpenes and cannabinoids having different quantitative contents and ratios [10,11,12,13,14,15,16]. Of course, both the cannabis chemotype used and the patient’s genetics play a major role in the treatment. In addition, the amount used in one patient may be too high and in another one insufficient. At present, we need to know much more about the biodynamic effect of terpenes in cannabis to breed cannabis plants that are suitable for therapeutic use. We must understand that the therapeutic effectiveness of terpenes contained in cannabis is different when we use plant material (by smoking, vaporization, or in capsules), or as extracts (in oil, capsules, suppositories, creams, and the other preparations). We must also understand that many terpenes are not stable compounds. It is possible that some of these phytochemicals are artifacts that formed in the resin on the plant due to various reasons (as described below); for instance, UV sunlight exposure, harvesting, drying, storage and processing of the plant, and even during the analysis. Smoking and vaporization give rise to other substances, not fully studied, that can also affect patients (or other users) either positively or negatively. So far, there is a discussion on whether terpenes act as such or have a synergistic or entourage effect [17,18,19,20,21,22].
LaVigne [23] found that the terpenes α-humulene, geraniol, linalool, and β-pinene produced cannabinoid tetrad behaviors in mice [24,25,26,27], suggesting cannabimimetic activity. Further, some mice behaviors could be blocked by cannabinoid or adenosine receptor antagonists, suggesting a mixed mechanism of action.
To mimic vaporizable cannabis concentrates, experiments with terpenes/terpenoids, lignan, and flavonoid gave rise to twelve of the most abundant degradation byproducts—isoprene, 2,5-dihydrotoluene, 6-methyl-5-hepten-2-one, benzene, acrolein, formaldehyde, acetaldehyde, acetone, methacrolein, valeraldehyde, hexaldehyde, 2-butanone, and ultrafine particles [28].
Bernhard and Marr [29] found several products formed from D-limonene autooxidation. They tentatively identified two of them as D-carvone and trans-carveol. Karlberg et al. [30] performed GC and GC/MS analysis on air-exposed samples of D-limonene (mw 136) and identified five main compounds: carvone (mw 150), cis- and trans-limonene oxide (mw 152), cis- and trans-carveol (mw 152). They found that (R)-(-)-carvone and a mixture of cis and trans isomers of limonene oxide are potent allergens. Their next study [31] showed that hydroperoxides of D-limonene are potent allergens. The cis- and trans-limonene-2-hydroperoxides (mw 168) are the most abundantly formed compounds in the autoxidation of D-limonene by air. Autoxidation of D-limonene resulted in other potent allergens, (+)-limonene-l,2-oxide and carvone (Figure 1).
A later, more advanced study by Nilsson et al. [32] revealed many other air-oxidized products of D-limonene. The products are cis- and trans-limonene-l,2-oxide, cis- and trans-carveol, R-(-)-carvone, cis- and trans-limonene-2-hydroperoxide, cis- and trans-p-mentha-2,8-dien-l-ol, cis- and trans-p-mentha-2,8-diene-l-hydroperoxide, cis- and trans-limonene-2-hydroperoxide, and p-menth-8-ene-l,2-diol. In 1999, data on oxidation kinetics and product yields were published for 23 terpenes and 65 oxidation products [33]. Oxidized limonene and linalool caused contact allergy in dermatitis patients [34,35]. Similarly, hydroperoxides of limonene were contact allergens [36].
The main oxidation product of linalool was isolated and identified as 7-hydroperoxy-3,7-dimethyl-octa-1,5-diene-3-ol [37]. Later, Sköld et al. [38] published contact allergens originating by air exposure of linalool 1 (mw 154). The primary allergens identified were 7-hydroperoxy-3,7-dimethylocta-1,5-diene-3-ol (the main one in an oxidized sample) (mw 186) 2, 6-hydroxy-2,6-dimethylocta-2,7-dienal (mw 168) 4, 2,6-dimethylocta-3,7-diene-2,6-diol (mw 170) 5, 2,6-dimethylocta-1,7-diene-3,6-diol (mw 170) 6, 2-(5-methyl-5-vinyltetrahydrofuran-2-yl)propan-2-ol (mw 170) 8, and 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol (mw 170) 9. The presence of 6-hydroperoxy-3,7-dimethylocta-1,7-diene-3-ol (mw 186) 3 and 2,6-dimethylocta-2,7-diene-1,6-diol (mw 170) 7 was also detected (Figure 2).
Linalool is not an allergen, but air-oxidized linalool can trigger contact allergies [39,40].
The atmospheric oxidation of three terpenes was studied by Grosjean et al. [41]. After sunlight irradiations of mixtures of terpene and NO in air, reaction products were positively identified. Limonene produced 4-acetyl-1-methylcyclohexene, formaldehyde, and glyoxal. α-Pinene oxidation gave rise to formaldehyde, acetone, pinonaldehyde, and glyoxal. Oxidation products of β-pinene: 6,6-dimethylbicyclo[3.1.1]heptan-2-one, formaldehyde, and acetone.
Caryophyllene oxidized to just one product with low-sensitizing potential (an allergen of moderate strength), caryophyllene oxide [42]. Later, these authors identified two hydroperoxides to be primary oxidation products, but due to instability, they are rapidly converted to a more stable and less reactive secondary oxidation product—caryophyllene oxide [43] (Figure 3).
Thermal degradation of camphene, Δ3-carene, limonene, and α-terpinene was published by McGraw et al. [44]. The major monoterpene alcohols of the essential oil undergo isomerization and oxidization reactions during steam distillation. Nerol and geraniol predominantly isomerize; their conversion gives rise to linalool and α-terpineol. Linalool is converted into isomeric furan and pyran linalool oxides, 2,6-dimethyl-3,7-octadiene-2,6-diol and 2,6-dimethyloct-7-en-2,6-diol (Figure 4). The chemical conversion of analytical targets during sample clean-up by steam distillation is objectionable and interferes with precise hop oil analysis [45].
We must take into consideration that, upon aging, essential oils can undergo oxidation and polymerization, which may result in a loss of pharmacological properties. Heat, light, and air can lead to their oxidation, polymerization, isomerization, thermal rearrangement, or dehydrogenation [46]. Inflorescence stored using the novel packaging approach is a significant step towards providing patients with cannabis inflorescence of reproducible and reliable terpene content, an important component of inflorescence efficacy [47].
The aim of this study was to compare three different gas chromatography/mass spectrometry methods—hexane-based liquid extraction (Liq), static headspace extraction (HS), and headspace solid-phase microextraction (SPME)— to determine which method best identified volatile compounds in cannabis samples, mainly monoterpenes/monoterpenoids and sesquiterpenes/sesquiterpenoids. We used four chemotypes to compare possibilities of content compounds’ identification in different samples.

2. Experimental

2.1. Methods

Standards: Commercially available standards for α-pinene, camphene, β-pinene, myrcene, Δ3-carene, α-terpinene, p-cymene, limonene, 1,8-cineole, α-ocimene, trans-β-ocimene, γ-terpinene, terpinolene, linalool, isopulegol, geraniol, β-caryophyllene, α-humulene, cis-nerolidol, trans-nerolidol, caryophyllene oxide, guaiol, and α-bisabolol were obtained from Restek (Bellefonte, PA, USA).
Plant material: Dry female flowering tops of four different chemotypes (LOH LL1—Green fields chemotype, LOH LL2—Titan chemotype, LOH LL3—Black Domina chemotype, LOH LL4—Neptune chemotype) used for medical treatment, cultivated in Israel, were used for analysis. These four varieties that are used to treat patients were chosen so that we could compare the effectiveness of the given variety in treatment in relation to their content substances.
Sample preparation: n-Hexane for gas chromatography ≥ 98.0% (Merck, Rahway, NJ, USA) was used in sample processing. The ground plant material (three repetitions were performed for each analysis) was extracted with n-hexane (final concentration was 1 mg/mL) with occasional shaking for half an hour. One microgram of the sample thus prepared was injected for Liq analysis. A quantity of 25 mg of plant material was used for HS and 0.3 mg for SPME analysis.
Instrument: GC/MS [Agilent 7890B GC, Agilent 5977B MSD, PAL 3 (RSI 85)].
Column: Agilent Technologies, Inc., Santa Clara, CA, USA, HP-5MS UI, 30 m × 250 μm, film 0.25 μm.

2.2. Experimental Conditions for HS

Incubation time: 6 min; Incubation temperature: 80 °C.

2.3. Experimental Conditions for SPME

Incubation time: 10 min, incubation temperature: 60 °C, GC cycle time: 5 min, fiber conditioning station temperature: 250 °C, pre-desorption conditioning time: 2 min, sample extraction time: 10 min, sample desorption time: 1 min

2.4. Experimental Condition for All Three Analyses

The column temperature was initially 35 °C for 5 min, followed by temperature ramping from 35 to 150 °C at 5 °C/min, then to 250 °C at 15 °C/min (inlet: 250 °C; detector: 280 °C; split ratio 5:1;); gas: Helium (flow rate: 1 mL/min).
Analytical method validation—selectivity, specificity, accuracy, precision, linearity, range, limit of detection, limit of quantification, ruggedness, and robustness were performed [48]. They are beyond the scope of this manuscript and will be published in another publication.

2.5. Identification

The content compounds were identified by comparison to standards, retention times, retention indices, mass spectra, and the spectral matching of libraries NIST/EPA/NIH Mass Spectral Library 2017, Wiley Registry of Mass Spectral Data 11th Edition, FFNSC3, ©2015, and Adams Essential Oils Library.

3. Results

As we did not have all the main compounds as standards, it was impossible to quantify all these terpenes/terpenoids exactly.
Sample LOH LL1 (Table 1) revealed β-myrcene as the biggest peak in HS and β-caryophyllene in Liq and SPME methods. There are 8 different compounds (cpd) above 5%; in Liq—7 ones above 5%, in HS—3 above 5%, and in SPME—6 above 5%. Between the ten main compounds above, 5% were identified as β-myrcene—3x, limonene—1x, β-caryophyllene—3x, γ-elemene—1x, α-humulene—2x, α-bulnesene 2x, γ-selinene—2x, and selina-3,7(11)-diene—2x. Altogether, within the ten main compounds, 14 different terpenes/terpenoids were identified. Collectively, 51 compounds were identified by HS (98.03% of total volatiles), 46 compounds by SPME (88.36%) and 38 compounds by liquid (72.73%) GC/MS, together comprising 67 different volatile compounds. The same 28 compounds were found in all three analyses. A comparison of all three methods of analysis is presented in Figure 5.
Results of analysis of the sample LOH LL2 are presented in Table 2. Limonene was the biggest peak in HS and β-caryophyllene in Liq and SPME methods. Three different compounds were above 5%; in Liq—3 above 5%, in HS—6 above 5%, and in SPME—3 above 5%. Of the ten main compounds identified above, 5% were α-pinene 1x, β-pinene 1x, β-myrcene 1x, limonene 3x, β-caryophyllene—3x, and α-humulene—3x. Altogether, 17 different terpenes/terpenoids were found between the ten main compounds. The same 24 compounds were found in all three analyses. Altogether, 74 compounds were identified by HS (97.87% of total volatiles), 57 compounds by SPME (90.80%), and 38 compounds by liquid (80.02%) GC/MS, together comprising 94 different volatile compounds. A comparison of all three methods of analysis is presented in Figure 6.
In Table 3, limonene was the biggest peak in HS and SPME and selina-3,7(11)-diene in Liq. Next, 8 different compounds were above 5%; in Liq—5 above 5%, in HS—5 above 5%, and in SPME—6 above 5%. Between the ten main compounds identified using all three methods, the following were above 5%: α-pinene 1x, β-pinene 1x, β-myrcene—3x, limonene—3x, β-caryophyllene—3x, γ-selinene—2x, and selina-3,7(11)-diene—2x. Altogether, there were 20 different terpenes/terpenoids between the ten main compounds. The same 21 compounds were found in all three types of analysis. Altogether, 56 compounds were identified by HS (96.45%), 49 compounds by SPME (85.43%), and 44 compounds by Liq (86.85%) GC/MS, together comprising 84 different volatile compounds. A comparison of all three methods of analysis is presented in Figure 7.
Table 4 points out limonene as the biggest peak in HS and β-caryophyllene in Liq and SPME. Then, 4 different compounds were above 5%; in Liq—5 above 5%, in HS—5 above 5%, and in SPME—6 above 5%. Between the ten main compounds gathered from all three methods, the following were above 5%: β-pinene 1x, β-myrcene—2x, limonene—2x, β-caryophyllene—3x, α-humulene—3x, α-bulnesene 2x, and 10-epi-γ-eudesmol 1x. Altogether, 17 different terpenes/terpenoids were identified between the ten main compounds. The same 21 compounds were found in all three types of analysis. Altogether, 57 compounds were identified by HS (97.17%), 47 compounds by SPME (88.85%), and 34 compounds by Liq (88.10%) GC/MS, together comprising 77 different volatile compounds. A comparison of all three methods of analysis is presented in Figure 8.
A comparison of the number of identified substances for the four different chemotypes by the three different methods can be found in Table 5, and results of quantitative determination (liquid analysis) of compounds for which we had commercially available standards are in Table 6.

4. Discussion

Gas chromatography analysis of the essential oil from Cannabis sativa was published already in 1957 [49]. In oil from fresh large leaves of female Cannabis sativa, the compounds identified by gas chromatography were myrcene, limonene, α-humulene, and β-caryophyllene [50]. By steam distillation of fresh Indian Cannabis sativa L. from Kashmir 21, terpenes/terpenoids were identified in the essential oil [51].
Static headspace gas chromatography has already been used for marijuana and hashish analysis by Hood et al. [52,53]. They identified 16 terpenes and 1 terpenoid in the samples. For simultaneous quantification of 93 terpenoids present in air-dried Cannabis inflorescences and extracts static headspace—GC/MS/MS was used [54]. We also used GC/MS for identification of volatiles in different chemotypes of cannabis (medical and industrial) and published content volatiles, mostly terpenes/terpenoids, and their ratios in cannabis inflorescences and essential oils [55]. Thirteen chemotypes with different main terpenes/terpenoids were presented.
Solid-phase microextraction GC/MS was used to identify cannabidiol, Δ8-tetrahydrocannabinol, Δ9-tetrahydrocannabinol, and cannabinol in pure water and human saliva [56]. For cannabinoids determination in cannabis samples, the GC/MS method was developed [57]. Yang et al. [58] identified 13 monoterpenes, 4 monoterpenoids, and 14 sesquiterpenes in cannabis essential oil. The three mentioned gas chromatography techniques (HS, SPME, and liquid injection) were compared [59]. All three were excellent for the lower boiling monoterpenes. In HS, sesquiterpenes were underrepresented. SPME gave a stronger signal for early eluting sesquiterpenes. Higher boiling sesquiterpenes were only adequately represented in liquid injection (hexane extract). Myers et al. [60] compared headspace–syringe and liquid injection–syringe techniques to the more modern headspace solid-phase microextraction arrow and direct-immersion SPME arrow. They used 23 terpene/terpenoids standards and determined from the results that the liquid injection–syringe method is the most straightforward and robust method.
We compared three different gas chromatography/mass spectrometry methods—static headspace extraction, headspace solid-phase microextraction, and hexane-based liquid extraction—to identify volatile compounds in cannabis samples, mainly monoterpenes/monoterpenoids and sesquiterpenes/sesquiterpenoids. We found hexane to be the best solvent for analysis of liquid samples. Liquid samples give the most complex spectrum of the main mono- and sesquiterpenes/terpenoids as sesquiterpenes/sesquiterpenoids can be seen with higher retention times. Such liquid samples also have the advantage of absolute quantification of terpenes. The static headspace chromatogram gives the best representation of monoterpenes and monoterpenoids but a weaker signal for sesquiterpenes and sesquiterpenoids. Solid-phase microextraction gives a significant spectrum of sesquiterpenes and sesquiterpenoids with shorter retention times and weaker signal for monoterpenes and monoterpenoids.
The determination of substances in the sample depends on the sensitivity of the method used. The volatility of the given substance and the amount of sample used are also important. Therefore, some substances were not identified by all three methods.
It seems that the results of Liq and SPME are the most similar (but not in all cases), so the analysis of the extract prepared with an organic solvent (hexane) will be the most suitable for the quantitative determination of these substances.
Altogether, 26 terpenes/terpenoids were among the ten main present in four different chemotypes. They were divided with Liq containing 16 terpenes/terpenoids (2 terpenes, 1 terpenoid, 9 sesquiterpenes, and 4 sesquiterpenoids), 15 in HS (5 terpenes, 2 terpenoids, 8 sesquiterpenes), and 17 in SPME (4 terpenes, 3 terpenoids, 10 sesquiterpenoids). The main terpene in chemotype LOH LL3 from the HS and SPME methods was limonene, but as we can see from Table 3, the other terpenes/terpenoids do not follow the same relative ratio. Chemotype LOH LL4 has a similar situation. The main terpene in Liq and SPME is β-caryophyllene, but as we can see from Table 4, the other terpenes/terpenoids do not follow the same relative ratio. As we can see from Table 1, Table 2, Table 3 and Table 4, the terpenes found most often from amongst the ten mains were β-myrcene, limonene, β-caryophyllene, α-humulene, γ-selinene, and selina-3,7(11)-diene. The most reproducible analysis for quantitative analysis (three repetitions were performed for each analysis) appears to be from Liq samples.
It is now well known that different cannabis chemotypes (also mentioned as variety, strain, chemovar, cultivar, phenotype, or genotype) with the same content of major cannabinoids act differently in the treatment of the same patient. Not every chemotype is suitable for a given patient. Cannabis constituents (whether cannabinoids, terpenes/terpenoids, or the other bioactive substances) interact with each other and can thus increase (or decrease) the effectiveness of a given chemotype [17,61]. If these effects are independent, synergistic, or entourage, they still need to be thoroughly studied. In addition, each of us is genetically different, and therefore, one chemotype that is suitable for one patient might not be suitable for another one. It should also be emphasized that a given chemotype of cannabis which is suitable for a specific patient witha given disease may not (but sometimes may) cure a different disease.

5. Conclusions

In conclusion, we can say that for the final evaluation of the comparison of the three methods of analysis, extraction with hexane gives balanced results (which is advantageous for quantitative analysis), although the other two methods allowed for the identification of more substances. This means that the same method should be used everywhere for the quantitative evaluation of constituents in cannabis. Only in this way it will be possible to objectively compare the results from different laboratories. The differences for the same sample analyzed in different laboratories will then be within the allowable error range.
Strains of cannabis, their content, their quantities, and ratios—all this is important and can lead to the determination of the cannabis strain grown in a certainplace, which will enable the treatment of a certain disease. This work is not groundbreaking or a new discovery. It is just a cube in the mosaic, which, after filling it in, will determine the cannabis treatment strategy.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/app14156476/s1. Figure S1: Hexane based liquid extraction method (Liq)—sample LOH LL1 chemotype. Counts vs. Acquisition Time (min), Figure S2: Static head-space extraction method (HS)—sample LOH LL1 chemotype. Counts vs. Acquisition Time (min), Figure S3: Head-space solid phase microextraction method (SPME)—sample LOH LL1 chemotype. Counts vs. Acquisition Time (min), Figure S4: Hexane based liquid extraction method (Liq)—sample LOH LL2 chemotype. Counts vs. Acquisition Time (min), Figure S5: Static head-space extraction method (HS)—sample LOH LL2 chemotype. Counts vs. Acquisition Time (min), Figure S6: Head-space solid phase microextraction method (SPME)—sample LOH LL2 chemotype. Counts vs. Acquisition Time (min), Figure S7: Hexane based liquid extraction method (Liq)—sample LOH LL3 chemotype. Counts vs. Acquisition Time (min), Figure S8: Static head-space extraction method (HS)—sample LOH LL3 chemotype. Counts vs. Acquisition Time (min), Figure S9: Head-space solid phase microextraction method (SPME)—sample LOH LL3 chemotype. Counts vs. Acquisition Time (min), Figure S10: Hexane based liquid extraction method (Liq)—sample LOH LL4 chemotype. Counts vs. Acquisition Time (min), Figure S11: Static head-space extraction method (HS)—sample LOH LL4 chemotype. Counts vs. Acquisition Time (min), Figure S12: Head-space solid phase microextraction method (SPME)—sample LOH LL4 chemotype. Counts vs. Acquisition Time (min).

Funding

There were no external funding sources to the study in the preparation of data or the manuscript.

Data Availability Statement

The original contributions presented in the study are included in the article and Supplementary Materials files, further inquiries can be directed to the corresponding author.

Acknowledgments

My thanks to Margalit Lillie Beck for manuscript reading and language corrections.

Conflicts of Interest

The Author Lumír Ondřej Hanuš was employed by the company Asana Bio Group Ltd. The author declared that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Abbreviations

Liq: hexane-based liquid extraction; HS: static headspace extraction; SPME: headspace solid-phase microextraction; Key: RT = retention time, RI = retention index, cpd = compounds.

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Figure 1. Air oxidation of limonene.
Figure 1. Air oxidation of limonene.
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Figure 2. Air oxidation of linalool.
Figure 2. Air oxidation of linalool.
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Figure 3. Primary oxidation products of caryophyllene.
Figure 3. Primary oxidation products of caryophyllene.
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Figure 4. Thermal degradation products of geraniol and nerol.
Figure 4. Thermal degradation products of geraniol and nerol.
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Figure 5. Comparison of all three methods of analysis—sample LOH LL1 chemotype. Counts vs. Acquisition Time (min).
Figure 5. Comparison of all three methods of analysis—sample LOH LL1 chemotype. Counts vs. Acquisition Time (min).
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Figure 6. Comparison of all three methods of analysis—sample LOH LL2 chemotype. Counts vs. Acquisition Time (min).
Figure 6. Comparison of all three methods of analysis—sample LOH LL2 chemotype. Counts vs. Acquisition Time (min).
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Figure 7. Comparison of all three methods of analysis—sample LOH LL3 chemotype. Counts vs. Acquisition Time (min).
Figure 7. Comparison of all three methods of analysis—sample LOH LL3 chemotype. Counts vs. Acquisition Time (min).
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Figure 8. Comparison of all three methods of analysis—sample LOH LL4 chemotype. Counts vs. Acquisition Time (min).
Figure 8. Comparison of all three methods of analysis—sample LOH LL4 chemotype. Counts vs. Acquisition Time (min).
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Table 1. GC/MS identification of the dry flowering tops—sample LOH LL1 chemotype.
Table 1. GC/MS identification of the dry flowering tops—sample LOH LL1 chemotype.
PeakRT % (Liq)% (HS)%
(SPME)
CompoundsTypeRI
16.429 traces 2,3-butanediolglycol788
27.789traces 2,4-dimethylheptanehydrocarbon821
39.212traces Ethylbenzenearomatic hydrocarbon855
49.379traces 4-methyloctanehydrocarbon863
59.509traces p-xylenearomatic hydrocarbon865
69.524 traces 1-hexanolorganic alcohol868
710.718tracestraces Heptanalalkyl aldehyde901
811.2230.090.63 5,5-dimethyl-1-vinylbicyclo[2.1.1]hexanebicyclic monoterpene921
911.600 traces α-thujenebicyclic monoterpene929
1011.8080.472.71tracesα-pinenebicyclic monoterpene937
1112.3290.140.74tracesCamphenebicyclic monoterpene952
1212.810 traces Benzaldehydearomatic aldehyde962
1313.3720.864.930.20β-pinenebicyclic monoterpene979
1413.893 traces 6-methyl-5-hepten-2-oneunsaturated methylated ketone986
1514.0539.8048.9411.81β-myrceneacyclic monoterpene991
1614.887 tracesα-terpinenemonocyclic monoterpene1017
1715.111 tracestracesp-cymenemonocyclic monoterpene1025
1815.2473.2815.124.18Limonenemonocyclic monoterpene1030
1915.328 traces 1,8-cineolebicyclic monoterpenoid1032
2015.624 traces cis-β-ocimeneacyclic monoterpene1038
2115.969 tracestracestrans-β-ocimeneacyclic monoterpene1049
2216.273 tracestracesγ-terpinenemonocyclic monoterpene1060
2316.554 traces sabinene hydratebicyclic monoterpenoid1068
2417.243 0.160.15Terpinolenemonocyclic monoterpene1088
2517.6360.651.420.39Linaloolacyclic monoterpenoid1099
2618.0370.480.630.47fenchyl alcoholbicyclic monoterpenoid1113
2718.2860.310.35 cis-pinene hydratebicyclic monoterpenoid1121
2818.590 tracesneo-allo-ocimeneacyclic monoterpene1131
2919.079 traces Ipsdienolacyclic monoterpenoid1147
3019.6720.10tracestracesBorneolbicyclic monoterpenoid1166
3120.0250.110.100.10terpinen-4-olmonocyclic monoterpenoid1177
3220.4260.350.190.12α-terpineolmonocyclic monoterpenoid1189
3320.706 tracesDodecanealkane hydrocarbon1200
3424.931 tracesα-cubebenetricyclic sesquiterpene1351
3525.516tracestraces0.16Ylangenetricyclic sesquiterpene1372
3625.637tracestraces0.09α-copaenetricyclic sesquiterpene1376
3725.813 tracesβ-patchoulenetricyclic sesquiterpene1381
3825.997 tracestraces7-epi-sesquithujenebicyclic sesquiterpene1391
3926.206 tracesTetradecanealkane hydrocarbon1400
4026.462 traces0.21cis-β-caryophyllenebicyclic sesquiterpene1406
4126.6390.110.090.45cis-α-bergamotenebicyclic sesquiterpene1415
4226.79110.236.2313.63β-caryophyllenebicyclic sesquiterpene1419
4326.879 traces γ-maalienetricyclic sesquiterpene1430
4427.024 traces β-copaenetricyclic sesquiterpene1433
4527.1447.87 2.00γ-elemenemonocyclic sesquiterpene1434
4627.1600.570.662.09α-bergamotenebicyclic sesquiterpene1436
4727.2481.951.203.53α-guaienebicyclic sesquiterpene1439
4827.376tracestraces0.19guaia-6,9-dienebicyclic sesquiterpene1443
4927.585 0.32humulen-(v1)bicyclic sesquiterpene1455
5027.6495.642.728.35α-humulenemonocyclic sesquiterpene1454
5128.042tracestraces0.124,5-di-epi-aristolochenebicyclic sesquiterpene1467
5228.1940.640.190.91γ-muurolenebicyclic sesquiterpene1477
5328.282 traces α-amorphenebicyclic sesquiterpene1485
5428.3700.440.180.774a,8-Dimethyl-2-(prop-1-en-2-yl)-1,2,3,4,4a,5,6,7-octahydronaphthalenebicyclic sesquiterpene1492
5528.4341.340.452.25β-selinenebicyclic sesquiterpene1486
5628.555 0.51δ-selinenebicyclic sesquiterpene1488
5728.6271.650.593.20α-selinenebicyclic sesquiterpene1494
5828.8355.802.157.70α-bulnesenebicyclic sesquiterpene1505
5928.988 traces0.25γ-cadinenebicyclic sesquiterpene1513
6029.1241.400.422.22δ-amorphenebicyclic sesquiterpene1519
6129.3807.061.799.24γ-selinenebicyclic sesquiterpene1544
6229.4937.512.1312.16selina-3,7(11)-dienebicyclic sesquiterpene1542
6329.7573.182.15tracesgermacrene Bmonocyclic sesquiterpene1557
6430.1580.36traces caryophyllene oxidebicyclic sesquiterpenoid1581
6531.312 tracesCadalenebicyclic aromatic hydrocarbon1674
6631.5750.47 juniper camphorbicyclic sesquiterpenoid1691
6732.378 tracesGuaiazulenebicyclic sesquiterpene1775
73.23%98.03%88.34%
38 cpd51 cpd46 cpd
Table 2. GC/MS identification of the dry flowering tops—sample LOH LL2 chemotype.
Table 2. GC/MS identification of the dry flowering tops—sample LOH LL2 chemotype.
PeakRT% (Liq)% (HS)% (SPME)CompoundTypeRI
12.966 traces 2-methylbutanalsaturated fatty aldehyde662
24.578 traces 2-methyl-1-butanolalcohol739
36.373 0.22 DL-2,3-butanediolglycol773
46.510 traces 2,3-butanediolglycol788
57.7990.12 2,4-dimethyl-heptanehydrocarbon821
69.508 0.17 1-hexanolalcohol868
710.718 traces heptanalsaturated fatty aldehyde901
811.231 0.10 5,5-dimethyl-1-vinylbicyclo[2.1.1]hexanebicyclic monoterpene921
911.608 traces α-thujenebicyclic monoterpene929
1011.8080.995.130.28α-pinenebicyclic monoterpene937
1112.330.301.580.30camphenebicyclic monoterpene953
1212.811 traces benzaldehydearomatic aldehyde962
1313.3721.698.270.37β-pinenebicyclic monoterpene979
1413.901 0.24 2,2,4,6,6-pentamethylheptanehydrocarbon991
1514.0132.2312.112.64β-myrceneacyclic monoterpene991
1614.358 traces ethyl hexanoatefatty acid ester1000
1714.839 traces0.16α-terpinenemonocyclic monoterpene1017
1814.983 traces p-menth-1-enemonocyclic monoterpene1025
1915.111 traces0.22p-cymenemonocyclic monoterpene1025
2015.2727.9732.447.09limonenemonocyclic monoterpene1030
2115.336 0.10 1,8-cineolebicyclic monoterpenoid1032
2215.624 tracestracescis-β-ocimeneacyclic monoterpene1038
2316.017 0.20trans-β-ocimeneacyclic monoterpene1049
2416.282 traces0.09γ-terpinenemonocyclic monoterpene1060
2516.546 traces cis-sabinene hydratebicyclic monoterpenoid1070
2616.739 traces linalool oxidemonocyclic monoterpenoid1086
2717.283 0.51terpinolenemonocyclic monoterpene1088
2817.6441.733.693.45linaloolacyclic monoterpenoid1099
2917.7300.33 undecanehydrocarbon1100
3017.789 traces nonanal saturated fatty aldehyde1104
3118.0371.572.362.03fencholbicyclic monoterpenoid1113
3218.2861.231.500.49cis-pinene hydratebicyclic monoterpenoid1121
3318.438 traces tracesmethyl octanoatefatty acid ester1126
3418.590 0.15neo-allo-ocimeneacyclic monoterpene1131
3518.9190.150.17 trans-pinene hydratebicyclic monoterpenoid1140
3619.015 traces camphorbicyclic monoterpenoid1145
3719.119 traces tracescamphene hydratebicyclic monoterpenoid1148
3819.408 traces isoborneolbicyclic monoterpenoid1157
3919.6650.310.300.51borneolbicyclic monoterpenoid1166
4020.025 traces0.10terpinen-4-olmonocyclic monoterpenoid1177
4120.4181.290.982.41α-terpineolmonocyclic monoterpenoid1189
4220.6350.190.250.49ethyl octanoatefatty acid ester1196
4323.192 traces0.10bornyl acetatebicyclic monoterpenoid1286
4423.801 traces0.10(E)-4-decenoic acid methyl esterfatty acid ester1299
4524.202 traces0.10methyl decanoatefatty acid ester1325
4624.939 tracesα-cubebenetricyclic sesquiterpene1351
4725.525 traces0.24ylangenetricyclic sesquiterpene1372
4825.685 0.110.48ethyl trans-4-decenoatefatty acid ester1375
4925.837 0.090.36hexyl hexanoatefatty acid ester1384
5025.990 traces0.137-epi-sesquithujenebicyclic sesquiterpene1391
5126.086 0.100.38ethyl decanoatefatty acid ester1396
5226.246 tracestetradecanehydrocarbon1400
5326.302 tracescyperenetricyclic sesquiterpene1399
5426.3900.170.09 sesquithujenebicyclic sesquiterpene1402
5526.463 traces0.72cis-caryophyllenebicyclic sesquiterpene1406
5626.6470.290.32 cis-α-bergamotenebicyclic sesquiterpene1415
5726.80721.8015.8530.19β-caryophyllenebicyclic sesquiterpene1419
5827.047 0.6610,10-dimethyl-2,6-dimethylenebicyclo [7.2.0]undecanebicyclic sesquiterpene1440
5927.162.301.714.48α-bergamotenebicyclic sesquiterpene1435
6027.2480.14 traces0.35α-guaienebicyclic sesquiterpene1439
6127.376 traces guaia-6,9-dienebicyclic sesquiterpene1444
6227.465 traces epi-β-santalenebicyclic sesquiterpene1448
6327.480 0.09α-himachalenebicyclic sesquiterpene
6427.6499.185.6416.79α-humulenemonocyclic sesquiterpene1454
6527.809 tracesβ-santalenebicyclic sesquiterpene1462
6628.338 0.63α-curcumenearomatic sesquiterpene1483
6728.3700.470.28 selina-4,11-dienebicyclic sesquiterpene1474
6828.402 1.224a,8-dimethyl-2-(prop-1-en-2-yl)-1,2,3,4,4a,5,6,7-octahydronaphthalenebicyclic sesquiterpene1492
6928.4430.500.221.22β-selinenebicyclic sesquiterpene1486
7028.587 0.271.26valencenebicyclic sesquiterpene1492
7128.6270.420.221.18α-selinenebicyclic sesquiterpene1494
7228.747 traces0.11β-dihydroagarofurantricyclic sesquiterpenoid1496
7328.8191.560.742.77α-farneseneacyclic sesquiterpene1508
7428.931 0.19β-curcumenemonocyclic sesquiterpene1514
7528.972 traces sesquicineole bicyclic sesquiterpenoid1516
7629.1400.650.291.38β-sesquiphellandrenemonocyclic sesquiterpene1524
7729.3890.900.121.05γ-selinenebicyclic sesquiterpene1538
7829.4930.850.271.55selina-3,7(11)-dienebicyclic sesquiterpene1542
7929.757 0.09 germacrene Bmonocyclic sesquiterpene1557
8029.7810.20 nerolidolacyclic sesquiterpenoid1544
8130.1581.060.17 caryophyllene oxidebicyclic sesquiterpenoid1581
8230.3343.600.150.34guaiolbicyclic sesquiterpenoid1596
8330.4550.18 traces 5-epi-7-epi-α-eudesmolbicyclic sesquiterpenoid1616
8430.527 traces humulene epoxide IIbicyclic sesquiterpenoid1606
8530.6634.970.180.5810-epi-γ-eudesmolbicyclic sesquiterpenoid1619
8630.7991.17 traces γ-eudesmolbicyclic sesquiterpenoid1631
8730.8590.23 agarospirolbicyclic sesquiterpenoid1645
8831.0401.66 traces β-eudesmolbicyclic sesquiterpenoid1649
8931.0722.99 traces α-eudesmolbicyclic sesquiterpenoid1653
9031.2244.25 traces0.11bulnesolbicyclic sesquiterpenoid1667
9131.320 0.10cadalenebicyclic aromatic hydrocarbon1674
9231.5750.35 juniper camphorbicyclic sesquiterpenoid1691
9332.523 0.09α-phellandrene dimertricyclic terpene1801
9433.733 traceshexadecanoic acidsaturated fatty acid1968
80.02%97.87%90.80%
38 cpd74 cpd57 cpd
Table 3. GC/MS identification of the dry flowering tops—sample LOH LL3 chemotype.
Table 3. GC/MS identification of the dry flowering tops—sample LOH LL3 chemotype.
PeakRT% (Liq)% (HS)% (SPME)CompoundTypeRI
18.987 traces 3-hexen-1-ol 856
29.398 traces 4-methyl-octanehydrocarbon863
39.5280.10 p-xylenearomatic hydrocarbon865
49.5080.140.480.221-hexanolorganic alcohol868
511.239 traces 5,5-dimethyl-1-vinylbicyclo[2.1.1]hexanebicyclic monoterpene921
611.608 0.14 tracesα-thujenebicyclic monoterpene929
711.8241.616.920.57α-pinenebicyclic monoterpene937
812.3450.462.000.13camphenebicyclic monoterpene952
913.3882.339.410.68β-pinenebicyclic monoterpene979
1014.0455.5821.609.79β-myrceneacyclic monoterpene991
1114.406 traces α-phellandrenemonocyclic monoterpene1005
1214.646 4.14Δ3-carenebicyclic monoterpene1011
1314.879 0.35α-terpinenemonocyclic monoterpene1017
1414.999 traces p-menth-1-enemonocyclic monoterpene1025
1515.119 traces5.41p-cymenemonocyclic monoterpene1025
1615.2888.6028.0913.92limonenemonocyclic monoterpene1030
1715.344 0.21 1,8-cineolebicyclic monoterpenoid1032
1815.632 traces cis-β-ocimeneacyclic monoterpene1038
1915.977 traces0.11trans-β-ocimeneacyclic monoterpene1049
2016.290 traces0.27γ-terpinenemonocyclic monoterpene1060
2116.554 traces cis-sabinene hydratebicyclic monoterpenoid1070
2216.322 tracesp-cresolphenol derivative1077
2316.875 0.79m-cymenenearomatic compound1082
2417.252 0.47 terpinolenemonocyclic monoterpene1088
2517.308 1.24p-cymenenearomatic compound1090
2617.6522.454.081.64linaloolacyclic monoterpenoid1099
2717.7300.20 undecanehydrocarbon1100
2818.0451.521.971.25fencholbicyclic monoterpenoid1113
2918.2860.910.96 trans-pinene hydratebicyclic monoterpenoid1132
3019.127 traces traces camphene hydratebicyclic monoterpenoid1148
3118.871 traces5-methyl-undecanehydrocarbon1156
3219.296 traces 2,3-dimethyldecanehydrocarbon1157
3319.6730.430.380.35borneolbicyclic monoterpenoid1166
3419.817 traces0.103-methyl-undecanehydrocarbon1170
3520.025 traces0.35terpinen-4-olmonocyclic monoterpenoid1177
3620.178 0.19p-cymene-8-olmonocyclic monoterpenoid1183
3720.4261.210.660.61α-terpineolmonocyclic monoterpenoid1189
3820.627 tracesmyrtenalbicyclic monoterpenoid1193
3920.705 traces dodecanehydrocarbon1200
4023.192 traces bornyl acetatebicyclic monoterpenoid1286
4123.585 0.15carvacrolmonoterpenoid phenol1299
4224.931 traces α-cubebenetricyclic sesquiterpene1351
4325.525 traces0.100.33ylangenetricyclic sesquiterpene1372
4425.637 traces0.10copaenetricyclic sesquiterpene1376
4525.845 traces hexyl hexanoatefatty acid ester1384
4625.893 tracesα-bourbonenetricyclic sesquiterpene1384
4726.182 traces tetradecanehydrocarbon1400
4826.471 0.10cis-β-caryophyllenebicyclic sesquiterpene1406
4926.7916.855.437.56β-caryophyllenebicyclic sesquiterpene1419
5027.1211.90 0.22γ-elemenemonocyclic sesquiterpene1434
5127.1600.440.420.87α-bergamotenebicyclic sesquiterpene1435
5227.248 traces tracesα-guaienebicyclic sesquiterpene1439
5327.376 traces0.12guaia-6,9-dienebicyclic sesquiterpene1444
5427.545 0.24humulen-(v1)bicyclic sesquiterpene1455
5527.6492.361.513.07α-humulenemonocyclic sesquiterpene1454
5628.2020.350.220.56γ-muurolenebicyclic sesquiterpene1477
5728.290 traces0.25α-amorphenebicyclic sesquiterpene1482
5828.386 0.414a,8-dimethyl-2-(prop-1-en-2-yl)-1,2,3,4,4a,5,6,7-octahydronaphthalenebicyclic sesquiterpene1492
5928.3780.200.15 selina-4,11-dienebicyclic sesquiterpene1474
6028.4430.790.381.27β-selinenebicyclic sesquiterpene1486
6128.531 traces δ-selinenebicyclic sesquiterpene1495
6228.6271.200.631.89α-selinenebicyclic sesquiterpene1494
6328.7490.12 β-dihydroagarofurantricyclic sesquiterpenoid1496
6428.8191.010.490.97α-farneseneacyclic sesquiterpene1508
6528.9960.10 traces0.18γ-cadinenebicyclic sesquiterpene1513
6629.132 2.52δ-amorphenebicyclic sesquiterpene1497
6729.38810.003.268.90γ-selinenebicyclic sesquiterpene1544
6829.469 1.33α-bisabolenemonocyclic sesquiterpene1540
6929.50113.544.2711.69selina-3,7(11)-dienebicyclic sesquiterpene1542
7029.7571.740.85 germacrene Bmonocyclic sesquiterpene1557
7130.1580.34 traces caryophyllene oxidebicyclic sesquiterpenoid1581
7230.3343.090.10 guaiolbicyclic sesquiterpenoid1596
7330.4500.18 5-epi-7-epi-α-eudesmolbicyclic sesquiterpenoid1616
7430.6633.760.11 10-epi-γ-eudesmolbicyclic sesquiterpenoid1619
7530.7991.25 traces γ-eudesmolbicyclic sesquiterpenoid1631
7630.8590.20 agarospirolbicyclic sesquiterpenoid1645
7731.0451.45 traces β-eudesmolbicyclic sesquiterpenoid1649
7831.0723.15 traces α-eudesmolbicyclic sesquiterpenoid1653
7931.2243.60 traces bulnesolbicyclic sesquiterpenoid1667
8031.312 0.16cadalenebicyclic aromatic hydrocarbon1674
8131.3772.00 traces α-bisabololmonocyclic sesquiterpenoid1684
8231.5751.02 juniper camphorbicyclic sesquiterpenoid1692
8332.523 tracesα-phellandrene dimertricyclic terpene1801
8432.7190.23 selina-4,7-diolbicyclic sesquiterpenoid1826
86.85%96.45%85.43%
44 cpd56 cpd49 cpd
Table 4. GC/MS identification of the dry flowering tops—sample LOH LL4 chemotype.
Table 4. GC/MS identification of the dry flowering tops—sample LOH LL4 chemotype.
PeakRT% (Liq)% (HS)% (SPME)CompoundTypeRI
19.3980.06 4-methyl-octanehydrocarbon863
29.515 0.22 1-hexanolorganic alcohol868
3 traces o-xylenearomatic hydrocarbon887
410.341 traces 2-heptanoneketone891
510.734 traces heptanalalkyl aldehyde901
611.239 0.29 5,5-Dimethyl-1-vinylbicyclo[2.1.1]hexanebicyclic monoterpene921
711.600 1.330.103-methyl-2-butenoic acid ethyl esterfatty acid ester924
811.8240.644.410.15α-pinenebicyclic monoterpene937
912.3450.191.330.18camphenebicyclic monoterpene952
1012.818 traces benzaldehydearomatic aldehyde962
1113.3790.915.99 β-pinenebicyclic monoterpene979
1213.941 traces6-methyl-5-heptene-2-oneunsaturated methylated ketone986
1313.917 0.17 2,2,4,6,6-pentamethylheptanehydrocarbon991
1414.0373.3019.696.11β-myrceneacyclic monoterpene991
1514.398 0.02 α-phellandrenemonocyclic monoterpene1005
1614.846 traces tracesα-terpinenemonocyclic monoterpene1017
1714.999 traces p-menth-1-enemonocyclic monoterpene1025
1815.039 tracesisomyrcenolacyclic monoterpenoid1022
1915.119 traces tracesp-cymenemonocyclic monoterpene1025
2015.2714.3922.626.07limonenemonocyclic monoterpene1030
2115.343 0.12 1,8-cineolebicyclic monoterpenoid1032
2215.632 traces cis-β-ocimeneacyclic monoterpene1038
2316.025 0.11trans-β-ocimeneacyclic monoterpene1049
2416.289 traces tracesγ-terpinenemonocyclic monoterpene1060
2516.562 traces cis-sabinene hydratebicyclic monoterpenoid1070
2617.291 0.26terpinolenemonocyclic monoterpene1088
2717.6441.283.271.93linaloolacyclic monoterpenoid1099
2817.813 tracesnonanalaldehyde1104
2918.0450.641.250.72fencholbicyclic monoterpenoid1113
3018.2940.390.630.15trans-pinene hydratebicyclic monoterpenoid1140
3118.598 0.10allo-ocimeneacyclic monoterpene1144
3218.927 traces cis-pinene hydratebicyclic monoterpenoid1121
3319.135 traces camphene hydratebicyclic monoterpenoid1148
3419.6720.220.240.20borneolbicyclic monoterpenoid1166
3520.033 traces0.11terpinen-4-olmonocyclic monoterpenoid1177
3620.4260.590.480.80α-terpineolmonocyclic monoterpenoid1189
3721.147 traces2,4-dimethyl-benzaldehydearomatic aldehyde1181
3824.931 traces α-cubebenetricyclic sesquiterpene1351
3915.196 0.10clovenetricyclic sesquiterpene1440
4025.524 traces0.15ylangenetricyclic sesquiterpene1372
4125.645 traces tracescopaenetricyclic sesquiterpene1376
4225.989 traces traces7-epi-sesquithujenebicyclic sesquiterpene1391
4326.390 traces sesquithujenebicyclic sesquiterpene1402
4426.462 traces0.38cis-caryophyllenebicyclic sesquiterpene1406
4526.6470.170.24 cis-α-bergamotenebicyclic sesquiterpene1415
4626.80716.3715.5618.65β-caryophyllenebicyclic sesquiterpene1419
4727.023 traces β-copaenetricyclic sesquiterpene1432
4827.1682.231.643.86trans-α-bergamotenebicyclic sesquiterpene1435
4927.2562.792.764.73α-guaienebicyclic sesquiterpene1439
5027.464 traces epi-β-santalenebicyclic sesquiterpene1448
5127.585 0.40humulene-(v1)bicyclic sesquiterpene1455
5227.6577.505.5711.76α-humulenemonocyclic sesquiterpene1454
5328.042 traces aristolochenebicyclic sesquiterpene1476
5428.050 0.12drima-7,9-dienebicyclic sesquiterpene1461
5528.330 0.58α-curcumenemonocyclic sesquiterpene1483
5628.378 0.260.884a,8-dimethyl-2-(prop-1-en-2-yl)-1,2,3,4,4a,5,6,7-octahydronaphthalenebicyclic sesquiterpene1492
5728.4421.260.672.99β-selinenebicyclic sesquiterpene1486
5828.6271.540.793.85α-selinenebicyclic sesquiterpene1494
5928.8356.893.318.51α-bulnesenebicyclic sesquiterpene1505
6029.012 0.20γ-cadinenebicyclic sesquiterpene1513
6129.3804.151.425.06γ-selinenebicyclic sesquiterpene1538
6229.468 1.08α-bisabolenemonocyclic sesquiterpene1540
6329.4935.532.017.04selina-3,7(11)-dienebicyclic sesquiterpene1542
6429.7570.820.30 germacrene Bmonocyclic sesquiterpene1557
6530.1580.77 traces caryophyllene oxidebicyclic sesquiterpenoid1581
6630.3424.590.18 tracesguaiolbicyclic sesquiterpenoid1596
6730.438 tracesβ-atlantolmonocyclic sesquiterpenoid1607
6830.4540.35 traces 5-epi-7-epi-α-eudesmolbicyclic sesquiterpenoid1616
6930.6635.020.190.1910-epi-γ-eudesmolbicyclic sesquiterpenoid1619
7030.7991.81 traces γ-eudesmolbicyclic sesquiterpenoid1631
7130.8590.33 agarospirolbicyclic sesquiterpenoid1645
7231.0402.56 traces β-eudesmolbicyclic sesquiterpenoid1649
7331.0724.760.10 α-eudesmolbicyclic sesquiterpenoid1653
7431.2324.820.09 tracesbulnesolbicyclic sesquiterpenoid1667
7531.312 tracescadalenebicyclic aromatic hydrocarbon1674
7631.3800.60 α-bisabololmonocyclic sesquiterpenoid1684
7731.5750.54 juniper camphorbicyclic sesquiterpenoid1691
88.10%97.17%88.85%
34 cpd57 cpd47 cpd
Table 5. Number of identified compounds in different samples by three different methods and all identified different compounds in each chemotype from all three methods.
Table 5. Number of identified compounds in different samples by three different methods and all identified different compounds in each chemotype from all three methods.
GC/MSLOH LL1LOH LL2LOH LL3LOH LL4
Liquid37384534
HS51745557
SPME46574947
All identified different compounds67948477
Table 6. Quantitative determination (liquid analysis) of terpenes/terpenoids for which there were commercially available standards.
Table 6. Quantitative determination (liquid analysis) of terpenes/terpenoids for which there were commercially available standards.
CompoundLOH LL1
µg/g
LOH LL2
µg/g
LOH LL3
µg/g
LOH LL4
µg/g
α-pinene45.660.0101.647.0
camphene13.518.3329.3814.4
β-pinene83.7102.0147.562.0
β-myrcene2136.2294.3744.1544.2
limonene473.3705.9803.7457.1
linalool151.5236.1367.6231.3
β-caryophyllene1322.11704.0542.11599.4
α-humulene535.0538.4152.1605.2
caryophyllene oxide0.10.20.20.2
guaiol-313.7288.8522.3
α-bisabolol--170.064.7
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Hanuš, L.O. Comparison of Three Gas Chromatographic Methods—Identification of Terpenes and Terpenoids in Cannabis sativa L. Appl. Sci. 2024, 14, 6476. https://doi.org/10.3390/app14156476

AMA Style

Hanuš LO. Comparison of Three Gas Chromatographic Methods—Identification of Terpenes and Terpenoids in Cannabis sativa L. Applied Sciences. 2024; 14(15):6476. https://doi.org/10.3390/app14156476

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Hanuš, Lumír Ondřej. 2024. "Comparison of Three Gas Chromatographic Methods—Identification of Terpenes and Terpenoids in Cannabis sativa L." Applied Sciences 14, no. 15: 6476. https://doi.org/10.3390/app14156476

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