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The volatile oils of fresh and air-dried buds of 3 different varieties of Cannabis, namely, high cannabidiol (CBD) chemotype, intermediate CBD/tetrahydrocannabinol (THC) chemotype, and high THC chemotype were prepared by hydrodistillation. Gas chromatography analysis of the volatile oils resulted in the identification of 71 compounds, of which 33 were monoterpenes and 38 were sesquiterpenes. The volatile oil obtained from the THC chemotype showed an increase in the ratio of the sesquiterpenes to monoterpenes content. The content of terpinolene was dramatically decreased upon drying of THC chemotype. Moderate increase in β-caryophyllene and caryophyllene oxide was observed. However, there was no detectable change in the percentage of monoterpenes and sesquiterpenes content in both the intermediate type and CBD chemotype upon drying. The insecticidal activity of the volatile oils was evaluated. The oil obtained from the fresh and dried high CBD cannabis showed good biting deterrent activity at 10 ug/cm ² compared with N, N-diethyl-meta-toluamide at 4.78 µg/cm ² , and good larvicidal activity.
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1National Center for Natural Products Research, School of Pharmacy,
University of Mississippi, University, MS, USA
2Department of Pharmacognosy, Faculty of Pharmacy, Minia University,
Minia, Egypt
3Department of Pharmacognosy, Faculty of Pharmacy, Near East University,
Nicosia, Cyprus
4Department of Pharmacognosy, Faculty of Pharmacy, Anadolu University,
Eskisehir, Turkey
5Department of Pharmaceutics and Drug Delivery, School of Pharmacy,
University of Mississippi, MS, USA
Corresponding Author:
Mahmoud A. ElSohly, National Center for Natural Products Research,
School of Pharmacy, University of Mississippi, University, MS 38677, USA.
Email: melsohly@ olemiss. edu
Bioactive Natural Products from Terrestrial and Marine Resources, Especially Terpenes, but not limited to- Original Article
Natural Product Communications
Volume 15(5): 1–7
© The Author(s) 2020
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Chemical Composition of Volatile Oils of
Fresh and Air- Dried Buds of Cannabis
chemovars, Their Insecticidal and
RepellentActivities
Amira S. Wanas1,2, Mohamed M. Radwan1, Suman Chandra1, Hemant Lata1, Zlatko Mehmedic1,
Abbas Ali1, KHC Baser3, Betul Demirci4, and Mahmoud A. ElSohly1,5
Abstract
The volatile oils of fresh and air- dried buds of 3 different varieties of Cannabis, namely, high cannabidiol (CBD) chemotype, inter-
mediate CBD/tetrahydrocannabinol (THC) chemotype, and high THC chemotype were prepared by hydrodistillation. Gas chro-
matography analysis of the volatile oils resulted in the identification of 71 compounds, of which 33 were monoterpenes and 38
were sesquiterpenes. The volatile oil obtained from the THC chemotype showed an increase in the ratio of the sesquiterpenes to
monoterpenes content. The content of terpinolene was dramatically decreased upon drying of THC chemotype. Moderate increase
in β-caryophyllene and caryophyllene oxide was observed. However, there was no detectable change in the percentage of mono-
terpenes and sesquiterpenes content in both the intermediate type and CBD chemotype upon drying. The insecticidal activity of
the volatile oils was evaluated. The oil obtained from the fresh and dried high CBD cannabis showed good biting deterrent activity
at 10 ug/cm2 compared with N,N- diethyl- meta- toluamide at 4.78 µg/cm2, and good larvicidal activity.
Keywords
cannabis essential oils, gas chromatography, insecticidal, larvicidal
Received: February 20th, 2020; Accepted: April 21st, 2020.
Terpenes are the main fragrant compounds in plant resins and
volatile oils responsible for the plants’ distinctive smells.
Terpenes in Cannabis plants are responsible for strain- specific
variations in the smell of the plants.1 The distinct scent of a
cannabis cultivar is the result of the balance of the different
terpenes produced by that particular plant’s breeding.2
Cannabis sativa plants are particularly rich in terpenes, repre-
sented by 120 compounds that are typically monoterpenes and
sesquiterpenes.3 The most common terpenes in cannabis are
β-caryophyllene, myrcene, limonene, α-pinene, β-pinene, α-hu-
mulene, and linalool.1 Monoterpenes are predominant in fresh
plant material but their yield diminishes upon drying and stor-
age,4,5 resulting in a higher relative proportion of sesquiter-
penes in dried cannabis.
Terpenoids play various ecological roles and their composi-
tion is under genetic control.6 They are considered as a contrib-
uting factor that determines plant community properties and
ecosystem functions and thought to have evolved primarily as
defense compounds. In addition, certain terpenoids in the mix-
ture may be recycled into the plant’s primary metabolism.
Other compounds are emitted into the environment, through
volatilization, decomposition of the plant, or by exudation,
playing a major role in numerous interactions. The remarkable
stickiness of cannabis exudates traps insects as it has insecti-
cidal and repellent activities7 and provides a synergistic mecha-
nochemical defense in combination with the insecticidal
phytocannabinoid acids, mainly tetrahydrocannabinolic acid
(THCA), cannabidiolic acid (CBDA), and cannabichromenic
acid (CBCA). These cannabinoids are biosynthesized from the
Natural Product Communications
2
common substrate, cannabigerolic acid, in the storage cavity of
the glandular trichomes.8
The lipophilic nature of terpenes increases the blood–brain
barrier permeability leading to many sites of pharmacological
actions.9 The therapeutic potential of terpenes are numerous,
including anti- inflammatory, anti- oxidant, analgesic, anticonvul-
sant, antidepressant, anticancer, antimutagenic, anesthetic, anti-
nociceptive, antihistaminic, and antispasmodic activities.1,10
Limonene displayed antinociceptive activity in chemical
nociceptive mice models and causes peripheral analgesia
through opioid receptors stimulation.11 Myrcene has potent
anti- inflammatory, analgesic, and anxiolytic properties.12
β-Caryophyllene (BCP) is the most common sesquiterpenoid
in cannabis plants and extracts, especially after heat decarbox-
ylation,13 was shown to be a selective natural CB2 receptor ago-
nist without psychoactivity.14
Literature reports suggest that besides the individual activi-
ties of terpenes, they are responsible for improving the canna-
binoids activities, a phenomenon referred to as known “the
entourage effect” especially in the treatment of pain.15
In continuation of our investigation of the cannabis volatile
oil,16 herein, we examined the different chemical composition
of the volatile oil of the cannabis chemotypes before and after
drying as well as their insecticidal activity.
Results and Discussion
The volatile oils of fresh (F) and air- dried buds (D) of 3 differ-
ent chemotypes of cannabis plant including CBD chemotype
(fiber type), CBD/THC chemotype (intermediate type), and
THC chemotype (drug type) were prepared by hydrodistilla-
tion. Gas chromatography (GC)–mass spectrometry (MS) and
GC/flame- ionization detector (FID) were used to analyze the
prepared volatile oils.
The GC–MS analysis resulted in the identification of 71
compounds with 33 monoterpenes and 38 sesquiterpenes. The
identification was based on a direct comparison with authentic
samples and/or by comparing the retention times and mass
spectral fragmentation with the data published by “Başer
Library of Essential Oil Constituents” and Wiley GC/MS
Library, MassFinder 3 Library. The percentage of each com-
pound was determined depending on its relative response in
the FID chromatograms. Table1 shows a list of all identified
compounds, relative retention indices, and their percentage
composition.
Generally, the composition of the different essential oils
varied and the percentage of monoterpenes decreased upon
drying. The collected data shows the change in the percentage
of the monoterpenes and the sesquiterpenes content in each
chemotype due to drying.
On drying of CBD chemotype, it was observed that the
monoterpenes content of the volatile oil was higher in the oil of
the fresh material (58.7%) than in the dried one (46.5%) (Table2).
The oil of the fresh fiber type (CBD chemovar) was rich in
myrcene (27.5%) and limonene (14%). An obvious increase in the
caryophyllene oxide content from 3.4% to 10.3% along with a
10% reduction in the myrcene content from 27.5% to 17.1% and
a slight change of the limonene from 17% to 14% were the most
significant changes on drying.
An increase in the percentage of sesquiterpenes from 61.0%
to 71.6% and a reduction of monoterpene content from 33.7%
to 25.5% was observed as a result of drying the THC chemo-
type plant material (Table2). The volatile oil of the fresh drug
type showed significant content of β-caryophyllene and ter-
pinolene compared with the other 2 types. Terpinolene content
was shown to decrease upon drying ranging from 9.4% to
1.7%. Moderate increase in β-caryophyllene and caryophyllene
oxide was observed.
However, there was no detectable change in the percentage
of the monoterpenes and sesquiterpenes content of the oil of
the intermediate chemovar upon drying. Its freshly prepared
oil was rich in α-pinene, β-pinene, and limonene. The relative
concentration of these compounds only slightly changed on
drying. The chemical structures of the major components of
the essential oil of cannabis are shown in Figure1.
Biting deterrent activity of these volatile oils was deter-
mined by using K&D bioassay.17 All the essential oils showed
higher biting deterrence activity than the solvent control, etha-
nol. The biting deterrent activity of essential oil of MX-2- F,
VI-2- F, and A-17–2- F was similar to N,N- diethyl- meta-
toluamide (DEET), whereas the activity of all the other essen-
tial oils was significantly lower than DEET (Figure2). Biting
deterrent activity of MX-2- D and VI-2- D was similar to etha-
nol. The oil obtained from the fresh and dried CBD chemo-
type cannabis showed good biting deterrent activity at 10 ug/
cm2 compared with DEET at 4.78 ug/cm2. Biting deterrent
activity of the essential oils is given in Figure2.
Out of 6 essential oils tested in our screening bioassay, only
4 oils showed larvicidal activity against 1- day old Aedes aegypti
larvae, whereas the others were inactive at the maximum dose
of 125 ppm (Table3). The 50% lethal concentration (LC50)
values for these 4 oils ranged between 21.5 and 27.5 ppm.
Based on 95% confidence interval (CI), LC50 values of VI-2- D
and A-17-2- F were similar to VI-2- F, whereas these values were
significantly lower than A-17-2- F. However, these variations
among the essential oils are very small. These data suggest that
some compounds or their combinations were responsible for
this activity. Further studies should focus on the testing of the
pure compounds from these oils to identify the compounds
responsible for these insecticidal activities.
Experimental
Plant Material
Indoor and outdoor C. sativa plants of 3 chemotypes (high
THC, THC/CBD, and high CBD) were grown at the University
of Mississippi. Outdoor grown plants were harvested in 2014
Wanas etal. 3
Table 1. The Chemical Composition of the Volatile Oils Prepared From Fresh and Dried Cannabis Samples.
Fiber type Intermediate type Drug type
RRI Compound V1-2- F V1-2- F (%) V1-2- D
(%)
A17-2- F
(%)
A17-2- D
(%)
MX-2- F
(%)
MX-2- D
(%)
1032 α-Pinene 2.2 4.0 15.4 15.6 3.6 6.0
1035 α-Thujene 0.1 0.2 0.2 0.2 0.2 0.3
1076 Camphene tr 0.1 0.3 0.3 0.1 0.2
1118 β-Pinene 1.5 2.1 7.8 7.5 2.3 3.5
1132 Sabinene 0.1 - - - 0.1 tr
1159 δ-3- Carene 0.3 - - - 0.3 0.3
1174 Myrcene 27.5 17.1 7.9 9.8 10.3 6.9
1188 α-Terpinene - - - - 0.2 -
1203 Limonene 14.0 17.0 33.0 27.1 1.2 1.9
1218 β-Phellandrene 0.6 0.2 0.1 0.2 0.6 0.4
1246 (Z)-β-Ocimene 0.2 tr 0.1 0.1 0.1 tr
1266 (E)-β-Ocimene 2.2 - 0.3 0.7 2.8 0.5
1280 p- Cymene 0.5 0.6 0.1 0.1 0.3 0.6
1290 Terpinolene 2.7 tr - 0.3 9.4 1.7
1429 Perillene tr 0.2 - - - -
1452 α,ρ-Dimethylstyrene 0.1 0.3 - - 0.2 tr
1474 trans- Sabinene hydrate 0.1 tr 0.1 0.1 tr tr
1477 4,8- Epoxyterpinolene 0.5 0.4 - 0.1 0.2 tr
1498 (E)- b- Ocimene epoxide 0.1 tr 0.1 - - -
1553 Linalool 0.3 0.3 1.0 0.9 0.6 0.8
1589 Isocaryophyllene 0.1 tr 0.2 0.2 0.2 tr
1594 trans-β-Bergamotene 0.5 0.9 0.3 0.3 0.6 0.7
1596 α-Guaiene 2.8 2.3 0.7 0.8 3.0 3.7
1611 Terpinen-4- ol 0.1 0.2 0.1 0.1 0.1 0.1
1612 β-Caryophyllene 7.6 6.2 6.6 9.0 16.5 20.7
1639 trans- p- Mentha-2,8- dien-1- ol 0.1 tr 0.2 tr - -
1650 γ-Elemene 0.1 tr 0.1 0.1 0.4 0.2
1661 Alloaromadendrene 0.1 0.2 - tr - -
1668 (Z)-β-Farnesene 0.4 0.4 0.2 0.4 0.7 0.7
1670 trans- Pinocarveol - - 0.2 0.1 - -
1687 α-Humulene 2.6 2.9 3.3 3.8 5.1 6.1
1688 Selina-4,11- diene 0.2 0.2 0.1 0.1 0.3 0.3
1704 γ-Muurolene - - 0.2 0.1 0.4 0.4
1706 α-Terpineol 0.6 0.8 0.9 0.9 0.3 0.3
1730 δ-Guaiene (=α-Bulnesene) 5.5 4.6 1.4 1.6 6.6 8.2
1740 Valencene - - 0.4 0.4 - -
1741 β-Bisabolene 0.9 1.0 tr -- 0.6 0.7
1742 β-Selinene 1.1 1.5 1.3 1.3 1.7 2.0
1744 α-Selinene 1.0 1.1 0.6 0.7 1.8 2.0
1747 Isoeremophilene 0.2 0.4 0.2 0.3 0.5 0.8
1751 Carvone - - 0.1 0.1 - -
1755 Bicyclogermacrene - - 0.2 - 0.2 0.3
1758 (E,E)-α-Farnesene 0.3 - - - 1.1 0.4
1773 δ-Cadinene 0.1 - - 0.1 0.2 tr
1776 γ-Cadinene 0.1 - - tr 0.2 tr
1785 7- epi-α-Selinene - - 0.2 0.2 - -
1784 (E)-α-Bisabolene 1.1 0.1 - 0.3 0.6 0.6
1796 Selina-3,7(11)- diene 4.1 3.7 2.5 3.0 9.1 13.2
1804 Myrtenol - - 0.1 0.1 - -
1830 2,6- Dimethyl-3(E),5(E),7 octatriene-2- ol 0.2 - 0.1 0.1 0.2 tr
1845 trans- Carveol 0.1 0.1 0.1 tr - -
1854 Germacrene- B 0.5 0.4 0.6 0.5 5.1 2.7
1864 p- Cymen-8- ol 1.6 2.5 0.1 0.2 0.5 1.6
(Continued)
Natural Product Communications
4
and indoor grown plants produced in 2017. Voucher speci-
mens from each variety were kept at the Coy Waller Laboratory,
University of Mississippi with codes CFP- MX, CFP- V1, and
CFP- A17 for high THC, high CBD, and THC/CBD, respec-
tively. Fresh mature buds of the 3 cannabis chemotypes were
harvested and divided into 2 equal parts of each chemotype.
One part of each kept fresh, while the other part air- dried at
room temperature for 1 week.
Preparation of the Volatile Oil
The volatile oil from each variety of fresh and dried plant
material was prepared by steam distillation using the Clevenger
apparatus. The terpene content of the prepared volatile oils
was determined by GC- FID analysis.
GC-FID Analysis
The GC- FID analysis was carried out using an Agilent 6890N
GC system, with the detector temperature set at 300°C. To
obtain the same elution order as with the GC–MS method,
simultaneous auto- injection was done on a duplicate of the
same column applying the same operational conditions.
Relative percentage amounts of the separated compounds
were calculated from the FID chromatograms. The analysis
results are given in Table1.
Identification of the essential oil components was carried
out by comparison of their relative retention times with those
of authentic samples or by comparison of their relative reten-
tion index (RRI) to a series of n- alkanes. Alternatively, com-
puter matching against commercial18,19 and in- house “Başer
Library of Essential Oil Constituents” built up by genuine
compounds and components of known oils, as well as MS lit-
erature data20,21 was also used for the identification.
GC–MS Analysis
The GC–MS analysis was carried out with an Agilent 5975 GC-
MSD system. Innowax FSC column (60 m × 0.25 mm internal
diameter and 0.25 μm film thickness) was used with helium as
carrier gas (0.8 mL/min). GC oven temperature was kept at
60°C for 10 minutes and programmed to 220°C at a rate of
4°C/min, and kept constant at 220°C for 10 minutes and then
programmed to 240°C at a rate of 1°C/min. Split ratio was
Fiber type Intermediate type Drug type
1882 cis- Carveol 0.1 0.2 0.2 0.1 - -
2001 Isocaryophyllene oxide 0.5 1.8 1.0 0.7 0.1 0.5
2008 Caryophyllene oxide 3.4 10.3 5.4 5.0 1.7 3.9
2030 Methyl eugenol 0.1 0.2 0.1 0.2 0.1 0.2
2045 Humulene epoxide- I 0.1 0.2 0.1 0.1 0.1 tr
2050 (E)- Nerolidol 0.3 0.7 0.4 0.5 0.5 0.3
2071 Humulene epoxide- II 0.9 3.0 1.8 1.6 0.4 0.8
2081 Humulene epoxide- III 0.3 1.9 tr 0.1 tr 0.2
2103 Guaiol - - - - 0.3 -
2127 10- epi−γ-Eudesmol - - - 0.3 -
2232 α-Bisabolol - 3.5 0.6 0.6 1.8 1.6
2250 α-Eudesmol - - - - 0.3 tr
2257 β-Eudesmol - - - - 0.3 tr
2269 Dimyrcene II- b - tr - - - -
2273 Porosadienol 0.3 0.5 - 0.4 0.6 0.4
2324 Caryophylla-2(12),6(13)- dien-5α-ol
(=Caryophylladienol II)
0.2 0.3 0.2 0.2 0.3 tr
2389 Caryophylla-2(12),6- dien-5α-ol (=Caryophyllenol
I)
- - - 0.2 0.3 -
2392 Caryophylla-2(12),6- dien-5β-ol (=Caryophyllenol
II)
0.1 0.4 0.2 0.2 0.2 0.2
RRI, relative retention indices; tr, traces (<0.1%).
RRI calculated against n- alkanes. Percentage calculated from flame ionization detector data.
Table 1. Continued
Table 2. Monoterpenes and Sesquiterpenes Contents of Cannabis
Volatile Oils.
Chemotype Monoterpenes (%) Sesquiterpenes (%)
V1-2- F 58.7 48.6
V1-2- D 46.5 35.6
A17-2- F 68.3 29.1
A17-2- D 64.3 32.8
MX-2- F 33.7 61.0
MX-2- D 25.5 71.6
Wanas etal. 5
adjusted at 40:1. The injector temperature was set at 250°C.
Mass spectra were recorded at 70 eV. Mass range was from m/z
35-450.
Insects
Yellow fever mosquitoes used in these studies were from a lab-
oratory colony maintained at the Mosquito and Fly Research
Unit, Center for Medical, Agricultural and Veterinary
Entomology, USDA- ARS, Gainesville, Florida, since 1952.
Mosquitoes were reared to the adult stage by feeding the larvae
on a larval diet of 2% slurry of 3:2 Beef Liver powder (now
Foods, Bloomingdale, Illinois) and Brewer’s yeast (Lewis
Laboratories Ltd., Westport, CT, USA). The eggs were hatched
and the larvae reared to pupal stage in an environment con-
trolled room maintained at 27 ± 2°C and 60 ± 10% relative
humidity in a photoperiod regimen of 12:12 (L:D) hour. The
adult mosquitoes were maintained in the laboratory using the
procedures described by Ali et al.22
In Vitro K&D Bioassay
Bioassays were conducted using a 6- celled in vitro Klun and
Debboun (K&D) bioassay system.17 Briefly, the bioassay sys-
tem consists of 6 (3 × 4 cm) wells each of which contains
approximately 6 mL of the feeding solution. As described by
Ali et al,22 a feeding solution consisting of citrate phosphate
dextrose adenine (CPDA-1) and adenosine triphosphate (ATP)
was used instead of blood. All the compounds were tested in
this study, and DEET, 97%, N, N- diethyl- meta- toluamide
(Cas# 134–62-3, Sigma- Aldrich, St. Louis, MO, USA) at 25
nmol/cm2 was used as a positive control. All the treatments
were freshly prepared in molecular biology grade 100% etha-
nol. The temperature of the feeding solution in the reservoirs
Figure 1. Chemical structures of the major components of volatile oils of cannabis.
Natural Product Communications
6
was maintained at 37°C by using a circulatory bath. The reser-
voirs were covered with a layer of collagen membrane (Devro,
Sandy Run, SC, USA). The test samples were randomly applied
to 6 (4 × 5 cm) marked areas of organdy (A fine, thin cotton
fabric) and positioned over the membrane- covered CPDA-1 +
ATP solution. The K&D module containing 5 female mosqui-
toes per cell was positioned over treated organdy and trap
doors were opened to expose the treatments to the females.
The number of mosquitoes biting through treated organdy in
each cell was recorded after a 3- minute exposure and mosqui-
toes were prodded back into the cells to check the actual
feeding. A replicate consisted of 6 treatments: 4 test samples,
DEET, and ethanol- treated organdy as solvent control.
Treatments were replicated 5 times.
Larvicidal Bioassays
Bioassays were conducted using the bioassay system described
by Pridgeon et al.23 Further methods and statistical analyses
were done as previously described by Ali et al.22
Dimethylsulfoxide was used as a solvent to prepare the treat-
ments and was also used as a negative control. Permethrin
Figure 2. Mean bting deterrence index (BDI) values of essential oils of cannabis chemovars against Aedes aegypti. All the essential oils were
tested at 10 ug/cm2. Ethanol was the solvent control and N,N- diethyl- meta- toluamide (DEET) at 25 nmol/cm2 was used as positive control.
Means were separated by using Ryan–Einot–Gabriel–Welsch multiple range test (P ≤ 0.05).
Table 3. Toxicity of Essential Oils of Cannabis Chemovars Against 1- Day- Old Aedes Aegypti Larvae at 24 Hours Post- Treatment.
Essential oil LC50 (95% CI)LC90 (95% CI)χ2df
MX-2- F >125
MX-2- D >125
V1-2- F 23.3 (20.8-26.1) 38.9 (33.7-48.1) 61.3 48
V1-2- D 21.5 (19.1-24.2) 38.7 (33.2-48.5) 67.8 48
A-17-2- F 21.8 (19.3-24.6) 40.6 (34.6-51.2) 70.5 48
A-17-2- D 27.5 (24.7-30.5) 42.6 (37.3-52.1) 52.5 48
Permethrina0.0034 (0.003-0.004)
df, degree of freedom; CI, confidence interval; LC50, 50% lethal concentration; LC90, 90% lethal concentration.
LC50 and LC90 values are in ppm.
aPositive standard, purity 46.1% and 53.2% for cis and trans, respectively.
Wanas etal. 7
(95.7%) (Chem Service, Inc. West Chester, PA, USA) was used
as a positive control.
Statistical Analyses
Proportion not biting (PNB) was calculated using the proce-
dure described by Ali et al.22
PNB = 1
(Total number of females biting
Total number of females )
Data on the PNB were analyzed using SAS Proc ANOVA
(SAS Institute, Inc., Carry, NC, USA, 2007) and means were
separated using Ryan–Einot–Gabriel–Welsch multiple range
test. LC50 values for larvicidal data were calculated by using
SAS, Proc Probit.
Declaration of Conf licting Interests
The author(s) declared no potential conflicts of interest with respect
to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support
for the research, authorship, and/or publication of this article: this
work was supported in part by the National Institute on Drug Abuse,
contract # N01DA-15-7793.
ORCID ID
Mahmoud A. ElSohly https:// orcid. org/ 0000- 0002- 0019- 2001
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... The terpenes are among the main compounds of the essential oil (EO) of cannabis [76]. Cannabis' EO is a liquid with a yellow color more or less pronounced, composed of mono-and sesquiterpenes but also of other molecules such as terpene alcohols and cannabinoids [75,[77][78][79][80]. Diverse biological activities have been associated with C. sativa EO including insecticidal, nematicide, antimicrobial, fungicidal, anti-leishmanial, antioxidant, anti-acetylcholinesterase or neuroactive activities [81][82][83][84][85]. The terpenes present in β-myrcene Caryophyllene Caryophyllene oxide α-humulene cannabis EO are responsible for the smell of the plant [7,81]. ...
... As mentioned above, biomass conditioning has a significant effect on the EO yield and composition. Drying and storing the plant lead to a significant decrease in the percentage of EO, as observed in several studies [83,87,91]. The two processes cause the evaporation of high vapor pressure components. ...
... The two processes cause the evaporation of high vapor pressure components. In particular, EO composition is characterized by a higher loss of the most volatile components, monoterpenes, and therefore an increased percentage of sesquiterpenes [83,87,91]. A further decrease in the EO yield occurs when the drying temperature is increased [98]. ...
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Cannabis sativa L. is a controversial crop due to its high tetrahydrocannabinol content varieties; however, the hemp varieties get an increased interest. This paper describes (i) the main categories of phenolic compounds (flavonoids, stilbenoids and lignans) and terpenes (monoterpenes and sesquiterpenes) from C. sativa by-products and their biological activities and (ii) the main extraction techniques for their recovery. It includes not only common techniques such as conventional solvent extraction, and hydrodistillation, but also intensification and emerging techniques such as ultrasound-assisted extraction or supercritical CO2 extraction. The effect of the operating conditions on the yield and composition of these categories of phenolic compounds and terpenes was discussed. A thorough investigation of innovative extraction techniques is indeed crucial for the extraction of phenolic compounds and terpenes from cannabis toward a sustainable industrial valorization of the whole plant.
... The studies included in the systematic review found remarkable toxicity of C. sativa extracts against all the Arachnida using mostly aerial parts and inflorescences. 12,56,65,69 In the Insecta group, C. sativa toxicity was reported against Oryzaephilus surinamensis, 61 Tribolium confusum, 61 Aedes aegypti, 70 Aedes albopictus, 53 Anopheles gambiae, 67 Anopheles stephensi, 67 Musca domestica, 15,54 Aulacorthum solani, 56 Brevicoryne brassicae, 52 Myzus persicae, 54 Schizaphis graminum, 12 Manduca sexta, 66 Plodia interpunctella, 61 Spodoptera littoralis, 15,54 Culex quinquefasciatus, 15,63 Sitophilus oryzae, 77 and Callosobruchus chinensis, 77,79 although one study found the C. sativa extract to be ineffective against C. quinquefasciatus. 54 Other species in which C. sativa extracts did not show relevant toxicities included Reticulitermes virginicus, 68 Brassicogethes aeneus, 72 Trogoderma granarium, 57 Chaoborus plumicornis, 68 Drosophila melanogaster, 68 and Frankliniella occidentalis. ...
... Unfortunately, 15 studies included in this review 12,55,56,58,59,62-65,70,74-79 did not perform phytochemical analyses, adding a notable degree of uncertainty that should be avoided in future research. The most commonly reported compounds in the studies reviewed that performed phytochemical analyses 15,[52][53][54]56,57,60,[67][68][69][70]72,73 were terpenoids [(E)-caryophyllene, trans-caryophyllene, myrcene, a-humulene, and a-pinene]. These volatile compounds are well known for their diverse biological activities against insects, because they can act as insecticides, 101 antifeedants, 102 or repellents, 103 among many other functions. ...
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Background: Despite the benefits that synthetic pesticides have provided in terms of pest and disease control, they cause serious long-term consequences for both the environment and living organisms. Interest in ecofriendly products has subsequently increased in recent years. Methods: This article briefly analyzes the available ethnobotanical evidence regarding the use of Cannabis sativa as a pesticide and offers a systematic review of experimental studies. Results: Our findings indicate that both ethnobotanical and experimental procedures support the use of C. sativa as a pesticide, as remarkable toxicity has been observed against pest organisms. The results included in the systematic review of experimental studies (n = 30) show a high degree of heterogeneity, but certain conclusions can be extracted to guide further research. For instance, promising pesticide properties were reported for most of the groups of species tested, especially Arachnida and Insecta; the efficacy of C. sativa as a pesticide can be derived from a wide variety of compounds that it contains and possible synergistic effects; it is crucial to standardize the phytochemical profile of C. sativa plants used as well as to obtain easily reproducible results; appropriate extraction methods should be explored; and upper inflorescences of the plant may be preferred for the production of the essential oil, but further studies should explore better other parts of the plant. Conclusion: In the coming years, as new findings are produced, the promising potential of C. sativa as a pesticide will be elucidated, and reviews such as the present one constitute useful basic tools to make these processes easier.
... Three types of terpenes/terpenoids are usually found in the cannabis plant which are (i) monoterpenes (10C) of two isoprene units; (ii) sesquiterpenes (15C) of three isoprenes; (iii) diterpenes (20C) of four isoprenes; and (iv) triterpenes (30C) of six isoprenes [26]. To date, more than 200 volatiles have been reported from the different cannabis genotypes of which 58 monoterpenes and 38 sesquiterpenes have been characterized [50][51][52][53]. Figure 5a illustrates a chromatogram of the terpene extract from the floral tissue of cannabis. Among others, the major monoterpene components are limonene, β-myrcene, α-pinene, and linalool with traces of α-terpinolene and tran-ocimene [54,55] (Figure 5b), while predominate sesquiterpenes are E-caryophyllene, caryophyllene oxide, E-β-farnesene, and β-caryophyllene [56]. ...
... β-Caryophyllene, a spice (pepper) aroma, is the most available sesquiterpenoid in cannabis plants and extracts, especially after decarboxylation by heat. It is an agonist with the CB2 receptor without psychoactivity [52]. It is also responsible for the cannabis anti-inflammatory effects [66]. ...
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Terpenes are the primary constituents of essential oils and are responsible for the aroma characteristics of cannabis. Together with the cannabinoids, terpenes illustrate synergic and/or entourage effect and their interactions have only been speculated in for the last few decades. Hundreds of terpenes are identified that allude to cannabis sensory attributes, contributing largely to the consumer’s experiences and market price. They also enhance many therapeutic benefits, especially as aromatherapy. To shed light on the importance of terpenes in the cannabis industry, the purpose of this review is to morphologically describe sources of cannabis terpenes and to explain the biosynthesis and diversity of terpene profiles in different cannabis chemovars.
... Likewise, yield obtained using Soxhlet was higher than other technologies such maceration and unconventional ultrasound assisted extraction. CSEO yield values vary widely depending on a wide range of factors such as plant part used for extraction (inflorescence, leaves, stems, etc), phenology, extraction time, solvent, extraction technology, drying methods among others as discussed in previous works (Amaducci et al., 2012;Wanas et al., 2020;Zeroual et al., 2021a, b). It is noteworthy that Fiorini et al. (2020) found that microwave-assisted extraction using high irradiation power and relatively long extraction times performed better in terms of essential oil yield and CBD content as compared to conventional hydrodistillation (Fiorini et al., 2019). ...
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Hemp known botanically as Cannabis sativa L. (CS) is an important industrial crop. A huge literature was devoted to its biology owing to its numerous health-healing properties and biotechnological applications. However, little is known about essential oil (CSEO) chemical composition in the cultivars grown in Morocco. In this research work, we aimed at investigating CSEO chemical composition of three cultivars namely: ‘Beldiya’, ‘Mexicana’, and ‘Critical Plus’. CSEOs were isolated from dried inflorescences using hydrodistillation and then subjected to chemical analysis using GC-MS. Our results showed that CSEOs yield and chemical composition varied significantly among cultivars. ‘Critical Plus’ showed the greatest record of CSEO yield (0.688%), while ‘Mexicana’ had the lowest value (0.330%). However, ‘Critical Plus’ presented the smallest values for the most of major compounds. Chemical composition showed an important phytochemical richness especially terpenoids. The most abundant compounds found in CSEOs were the following: β-caryophellene (13.39–25.32%), β-myercene (10.03–20.09), α-humulene (4.88–8.73%), caryophellene oxide (1.46–6.07%), decane (1.41–4.46%), and α-pinene (1.91–3.66%). The highest records of these compounds were reported in ‘Beldiya’ (β-caryophellene, caryophellene oxide, and decane) and ‘Mexicana’ (β-myercene, α-humulene, and α-pinene). Principal component analysis allowed a good separation of the three investigated cultivars based on their essential oil major compounds. It could be concluded that, the studied cultivars were caryophellene chemotypes, the local cultivar ‘Beldiya’ along with ‘Mexicana’ performed better in terms of essential oil yield and major phytochemicals over ‘Critical Plus’.
... Hemp EO is considered a niche product with high benefits and broad potential uses (Mediavilla and Steinemann 1997;Bertoli et al. 2010) from the cosmetic to the medical-pharmaceutical industry due to its natural antioxidant and antimicrobials (against Candida spp.) properties (Novak et al. 2001;Nissen et al. 2010;Nafis et al. 2019). Hemp EO has also been shown to have anti-leishmaniasis activities (Wanas et al. 2016), insecticidal and larvicidal activity against Aedes aegypti larvae (Górski et al. 2016;Bedini et al. 2016;Wanas et al. 2020), nematocide (Mukhtar et al. 2013), fungicide properties (Wielgusz et al. 2012), and allelopathic effect (Synowiec et al. 2016) finding utilization also in crop protection (Górski et al. 2016). Its use in the food sector is also very interesting and promising as flavoring for beverages and additives in pastry and catering (Meier and Mediavilla 1998). ...
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The use of hemp ( Cannabis sativa L.) essential oil (EO) has shown a significant increase in interest and use during recent years. In this work, a new and simple reversed-phase HPLC with photodiode-array (PDA) detector method has been developed and optimized for the detection and quantification of cannabidiolic acid (CBDA), cannabidiol (CBD), cannabinol (CBN), Δ9-tetrahydrocannabinol (Δ9-THC), and Δ9-tetrahydrocannabinolic acid (THCA). The cannabinoids were extracted from the EO by partition with n -hexane and water, followed by sonication, evaporation to dryness under nitrogen, and reconstitution with methanol:chloroform (9:1, v/v) before HPLC-PDA analysis. The method shows good selectivity and robustness, linearity in the range 0.5–100 mg L ⁻¹ with R ² higher than 0.999 for all cannabinoids analyzed, LOD of 0.11–0.16 mg L ⁻¹ , and LOQ of 0.35–0.48 mg L ⁻¹ . The recovery was between 78 and 100% and the intra-day and intermediate precision, expressed as relative standard deviation (RSD), was < 4% and 4–10%, respectively.
... The amount of the compounds belonging to this class of secondary metabolites is very different from those reported by Bertoli et al. [21], Benelli et al. [10] and Nissen et al. [28], in which the main detected chemical class was represented by monoterpenes, with significant differences between monoecious and dioecious genotypes; in these papers, however, the starting material consisted of the fresh inflorescences, rather than the dried ones. Assuming that the monoterpene content decreased in the drying process and storage [26,27,29,30], the predominance of sesquiterpenes in the examined EOs might be due, at least in part, to the drying process, which might have induced some changes in the chemical composition of the starting material, such as (i) evaporation of the low boiling-point compounds [27], and (ii) the induction of oxidative reactions, as in the conversion of βcaryophyllene in caryophyllene oxide, and α-humulene in humulene oxide II [30]. Nevertheless, few of the literature studies used the dried hemp inflorescences for the collection and characterization of the EOs. ...
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Cannabis sativa L. is an annual species cultivated since antiquity for different purposes. While, in the past, hemp inflorescences were considered crop residues, at present, they are regarded as valuable raw materials with different applications, among which extraction of the essential oil (EO) has gained increasing interest in many fields. The aim of the present study is the evaluation of the yield and the chemical composition of the EO obtained by hydrodistillation from eleven hemp genotypes, cultivated in the same location for two consecutive growing seasons. The composition of the EOs was analyzed by GC-MS, and then subjected to multivariate statistical analysis. Sesquit-erpenes represented the main class of compounds in all the EOs, both in their hydrocarbon and oxygenated forms, with relative abundances ranging from 47.1 to 78.5%; the only exception was the Felina 32 sample collected in 2019, in which cannabinoids predominated. Cannabinoids were the second most abundant class of compounds, of which cannabidiol was the main one, with relative abundances between 11.8 and 51.5%. The statistical distribution of the samples, performed on the complete chemical composition of the EOs, evidenced a partition based on the year of cultivation, rather than on the genotype, with the exception of Uso-31. Regarding the extraction yield, a significant variation was evidenced among both the genotypes and the years of cultivation.
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Background: Cannabis has a long history of being credited with centuries of healing powers for millennia. The cannabis plant is a rich source of cannabinoids and terpenes. Each cannabis chemovar exhibits a different flavor and aroma, which are determined by its terpene content. Methods: In this study, a gas chromatography-flame ionization detector method was developed and validated for the determination of the 10 major terpenes in the main three chemovars of Cannabis sativa L. with n-tridecane used as the internal standard following the standard addition method. The 10 major terpenes (monoterpenes and sesquiterpenes) are α-pinene, β-pinene, β-myrcene, limonene, terpinolene, linalool, α-terpineol, β-caryophyllene, α-humulene, and caryophyllene oxide. The method was validated according to Association of Official Analytical Chemists guidelines. Spike recovery studies for all terpenes were carried out on placebo cannabis material and indoor-growing high THC chemovar with authentic standards. Results: The method was linear over the calibration range of 1–100 μg/mL with r2>0.99 for all terpenes. The limit of detection and limit of quantification were calculated to be 0.3 and 1.0 μg/mL, respectively, for all terpenes. The accuracy (%recovery) at all levels ranged from 89% to 104% and 90% to 111% for placebo and indoor-growing high THC chemovar, respectively. The repeatability and intermediate precision of the method were evaluated by the quantification of target terpenes in the three different C. sativa chemovars, resulting in acceptable relative standard deviations (less than 10%). Conclusions: The developed method is simple, sensitive, reproducible, and suitable for the detection and quantification of monoterpenes and sesquiterpenes in C. sativa biomass.
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β-Caryophyllene is a natural bicyclic sesquiterpene found in many essential oils, including Cannabis sativa L. Due to its unique ability to selectively bind to the CB2 receptor, β-caryophyllene has been identified as an anti-inflammatory, antimicrobial, antitumor, and antioxidant agent. Moreover, β-caryophyllene is known to relieve anxiety, pain and is a valuable candidate for the treatment of neurodegenerative disorders, cancer, and osteoporosis. The determination of β-caryophyllene from essential oil requires time-consuming sample preparation and extraction from plant material. Solid-phase microextraction (SPME) allows the determination of β-caryophyllene directly in the solid or liquid sample. Nevertheless, selecting appropriate calibration media is crucial in this technique. In this work, seven deep eutectic solvents (DESs) were synthesised in a microwave reactor and investigated as a calibration media in SPME of β-caryophyllene from the complex matrix – hemp seed oil. The analyte was further identified by gas chromatographic – mass spectrometric analysis (GC-MS) and the selection criterion for the extraction efficiency was its peak area.
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The n-hexane extracted volatile fraction of high potency Cannabis sativa L (Cannabaceae). was assessed in vitro for antifungal, antibacterial and antileishmanial activities. The oil exhibited selective albeit modest, antifungal activity against Cryptococcus neoformans with an IC50 value of 33.1 μg/mL. Biologically-guided fractionation of the volatile fraction resulted in the isolation of three major compounds (1-3) using various chromatographic techniques. The chemical structures of the isolated compounds were identified as α-humulene (1), β-caryophyllene (2) and caryophyllene oxide (3) using GC/FID, GC/MS, 1D- and 2D-NMR analyses, respectively. Compound 1 showed potent and selective antifungal activity against Cryptococcus neoformans with IC50 and MIC values of 1.18 μg/mL and 5.0 μg/mL respectively. Whereas compound 2 showed weak activity (IC50 19.4 μg/mL), while compound 3 was inactive against C. neoformans.
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In this study we evaluated the biting deterrent effects of a series of saturated and unsaturated fatty acids against Aedes aegypti (L), yellow fever mosquito (Diptera: Culicidae) using the K & Dbioassay module system. Saturated (C6:0 to C16:0 and C18:0) and unsaturated fatty acids (C11:1 to C14:1, C16:1, C18:1, and C18:2) showed biting deterrence index (BDI) values significantly greater than ethanol, the negative control. Among the saturated fatty acids, mid chain length acids (C10:0 to C13:0) showed higher biting deterrence than short (C6:0 to C9:0) and long chain length acids (C14:0 to C18:0), except for C8:0 and C16:0 that were more active than the other short and long chain acids. The BDI values of mid chain length acids (C10:0 to C13:0) were not significantly less than N, N-diethyl-meta-toluamide (DEET), the positive control. Among the unsaturated fatty acids, C11:1 showed the highest activity (BDI = 1.05) and C18:2 had the lowest activity (BDI = 0.7). In C11:1, C12:1, and C14:1 BDI values were not significantly less than DEET. After the preliminary observations, residual activity bioassays were performed on C11:0, C12:0, C11:1, and C12:1 over a 24-h period. All the fatty acids (C11:0, C12:0, C11:1, and C12:1) and DEET showed significantly higher activity at all test intervals than the solvent control. At treatment and 1-h posttreatment, all fatty acids showed proportion not biting (PNB) values not significantly less than DEET. At 3-, 6-, and 12-h posttreatment, all fatty acids showed PNB values significantly greater than DEET. At 24-h posttreatment, only the PNB value for C12:0 was significantly higher than DEET. The dose-responses of C12:0 and DEET were determined at concentrations of 5-25 nmol/cm2. As in the residual activity bioassays, the PNB values for C12:0 and DEET at 25 nmol/cm(2) were not significantly different. However, at lower concentrations, the PNB values for C12:0 were significantly greater than DEET. These results clearly indicate that mid chain length fatty acids not only have levels of biting deterrence similar to DEET at 25 nmnol/cm(2) in our test system, but also appeared to be more persistent than DEET. In contrast, in vivo cloth patch assay system showed that the mid-chain length fatty acids, C11:0, C11:1, C12:0, and C12:1 had minimum effective dose (MED) values greater than DEET against Ae. aegypti and their relative repellency varied according to species tested. The MED values of 120 (C11:0), 145 (C12:0) and 116 (C11:1) nmol/cm(2) against Anopheles quadrimaculatus Say, indicated that these acids were not as potent as DEET with a MED of 54 nmol/cm(2). The MED ratio of the C11:0 and C11:1 for all three mosquito species indicated the C11 saturated and unsaturated acids as more repellent than their corresponding C12:0 and C12:1 homologues.
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Background.—Comprehensive literature reviews of historical perspectives and evidence supporting cannabis/ cannabinoids in the treatment of pain, including migraine and headache, with associated neurobiological mechanisms of pain modulation have been well described. Most of the existing literature reports on the cannabinoids Δ9 -tetrahydrocannabinol (THC) and cannabidiol (CBD), or cannabis in general. There are many cannabis strains that vary widely in the composition of cannabinoids, terpenes, flavonoids, and other compounds. These components work synergistically to produce wide variations in benefits, side effects, and strain characteristics. Knowledge of the individual medicinal properties of the cannabinoids, terpenes, and flavonoids is necessary to cross-breed strains to obtain optimal standardized synergistic compositions. This will enable targeting individual symptoms and/or diseases, including migraine, headache, and pain. Objective.—Review the medical literature for the use of cannabis/cannabinoids in the treatment of migraine, headache, facial pain, and other chronic pain syndromes, and for supporting evidence of a potential role in combatting the opioid epidemic. Review the medical literature involving major and minor cannabinoids, primary and secondary terpenes, and flavonoids that underlie the synergistic entourage effects of cannabis. Summarize the individual medicinal benefits of these substances, including analgesic and anti-inflammatory properties. Conclusion.—There is accumulating evidence for various therapeutic benefits of cannabis/cannabinoids, especially in the treatment of pain, which may also apply to the treatment of migraine and headache. There is also supporting evidence that cannabis may assist in opioid detoxification and weaning, thus making it a potential weapon in battling the opioid epidemic. Cannabis science is a rapidly evolving medical sector and industry with increasingly regulated production standards. Further research is anticipated to optimize breeding of strain-specific synergistic ratios of cannabinoids, terpenes, and other phytochemicals for predictable user effects, characteristics, and improved symptom and diseasetargeted therapies.
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Characteristics of higher plant terpenoids that result in mediation of numerous kinds of ecological interactions are discussed as a framework for this Symposium on Chemical Ecology of Terpenoids. However, the role of terpenoid mixtures, either constitutive or induced, their intraspecific qualitative and quantitative compositional variation, and their dosage-dependent effects are emphasized in subsequent discussions. It is suggested that little previous attention to these characteristics may have contributed to terpenoids having been misrepresented in some chemical defense theories. Selected phytocentric examples of terpenoid interactions are presented: (1) defense against generalist and specialist insect and mammalian herbivores, (2) defense against insect-vectored fungi and potentially pathogenic endophytic fungi, (3) attraction of entomophages and pollinators, (4) allelopathic effects that inhibit seed germination and soil bacteria, and (5) interaction with reactive troposphere gases. The results are integrated by discussing how these terpenoids may be contributing factors in determining some properties of terrestrial plant communities and ecosystems. A terrestrial phytocentric approach is necessitated due to the magnitude and scope of terpenoid interactions. This presentation has a more broadly based ecological perspective than the several excellent recent reviews of the ecological chemistry of terpenoids.