Various Cannabinoids and Related Compounds

• Author: James G. Wigmore
• Pages: 384-448

 

 

Various Cannabinoids and Related

Compounds

8.01 BOTANICAL CANNABIS

There has been a worldwide increase in the potency of botanical can-

nabis, such as mar ijuana and hashish (, , , ), which

has caused increases i n public health risks such as driving under the

inf‌luence of cannabis (DUIC) and psychological health problems. Since

live marijuana pla nts are  percent water, seized samples by the police

may decrease in weight by up to  percent as it dries out at ambient

temperatures () , and does not necessarily mean that t he police

were sampling the seized plants. Stored cann abis will also decrease in

THC concentration if exposed to sunlight or oxygen (). Marijuana

is a highly variable plant and the total cann abinoid content of seven

identical plants grown beside each other under controlled indoor grow-

ing conditions ranged from  to  percent ().

Botanical ca nnabis contains many other volatile compounds, but

the main distinction between cannabis a nd other related plants such

as hops is the presence of THC and CBN (, , ). Mature,

budding cannabis plant s have a stronger odour than non-mature plants

and are the easiest dr ug to detect by drug-sning dogs, such as German

Shepherd s (, ).

Reference Number: 80101

, ., . , .. ,  .. . “Dif‌fer-

entiation of Marijuana Headspace Volatiles from Other Plants and

Hemp Products Using Capillary Micro-Extraction of Volatiles (CMV)

Chapter 8: Various Cannabinoids and Related Compounds  

Reference Number: 

Coupled to Gas-Chromatography-Mass Spectrometry (GC-MS).” For-

ensic Chemistry, : –,  ( tables,  f‌igures,  references)

Abstract: Currently the main method of illicit drug detection is by

trained drug-sni ng canines. A new method to detect illicit drugs such

as marijuan a was developed to identify small qua ntities of drugs in a large

space. A capillary m icro-extraction of volatiles (CMV) pre-concentrates

the volatiles in the air with in minutes, which can then be analyzed by a

GC-MS. Whole hop leaf, hemp paper, hemp f‌ibres, ropes, seeds, a cigar,

and marijuan a samples were analyzed by this system. Of all the sa mples

analyzed, hops showed the most simila r volatile emissions to cannabis,

although THC was not detected in hops. Of the sixteen volati les found

in the headspace of cannabis samples, only alpha-santalene, valencene,

beta-bisabolene, and in some cases THC and cann abinol were detected

and specif‌ic to the mar ijuana sample.

Table: Comparison of Major Volatile Organic Compounds

Detected in Marijuana and Other Related Plants.*

Sample

Alpha Pinene

Beta Pinene

Beta Myrcene

Limonene

Beta Linalool

Beta

Caryophyllene

Alpha

Terpineol

tetrahydro-

cannabinol

cannabinol

Marijuana X X X X X X X X X

US Northern Brewer Hops XXXXX X

Whole sterilized hemp seeds X X X

Handmade hemp paper

Hemp rope

Cigar (tobacco) X

Tex as S age X X

Oakleaf Fig X

St. Augustine Gra ss X X

* X = Detected.

Source: Adapted from Wiebelh aus et al, 

The capillary micro-ex tractor of volatiles (CMV) was found to be a vi-

able complement to canine detection of illicit drug s, specif‌ically mari-

juana. Its ability to collect trace amount s of volatile compounds within

a short (approximately one minute) extraction time facilitates the d e-

velopment of a technique for f‌ield testing for the presence of mar ijuana

plants. The CMV was shown as a suitabl e investigative tool and it was

  Wigmore on Cannabis

Reference Number: 

also found that such a device could detect a collection of volatile com-

pounds that are characteristic to marijuana pla nts. These identif‌ied

compounds provide marijuana a distinct chemic al signature that can

be compared to other samples. In order to determine that the vola-

tile compounds identif‌ied are unique to marijuana he adspace, a more

diverse set of samples must be collected and a nalyzed. This will help

establish a collective chemical prof‌ile of mari juana that may be used for

comparisons. A database can then be created an d utilized for detecting

marijuana in multiple environments through u se of the CMV sampling.

Reference Number: 80102

, .., .. , . ,  .. . “Development and Valid-

ation of a Reliable and Robust Method for the Analysis of Cannabin-

oids and Terpenes in Cannabis.” Journal of the Association of Ocial

Agricultural Chemists International, : –,  ( tables,  f‌ig-

ures,  references)

Abstract: As of , there have been over  dif‌ferent chemical com-

pounds found in the cannabis pla nt, of which  are terpenoids. To

analyze the cannabinoids and terpenes in dr ied plant material, approxi-

mately  to  grams of the mar ijuana f‌lower or bud is homogenized in a

stainless-steel cof‌fee grinder and  mg of the grounds are placed in

a centrifuge tube with . mm of zirconia beads. Reagent grade etha-

nol, -biphenyl carboxylic acid (BPCA), and nonane (internal standard)

are added and the sample is centrifuged twice. The extract is analyzed

for cannabinoids using High Pressure Liquid Chromatography (HPLC)

with a diode array detector. HPLC is preferred for cannabinoids to pre-

vent degradation during analysis. The terpenes are measured using a

Gas Chromatograph (GC) with a f‌la me ionization detector. Cannabis is

a highly variable plant and the cannabinoid content of the f‌lowers is

very inhomogeneous. In one study of seven identical cannabis plants

that were grown indoors beside each other, the range of total canna-

binoids was from  to  percent w/w, and the total terpenes from .

to . percent. This variability is the reason why some medical ma ri-

juana manufacturers make extracts to ensure a more uniform product.

The variation in THC within the plant is greater than the variability

between plants.