Abstract
A recent cannabis use survey revealed that 60% of cannabis users rely on smelling
the flower to select their cannabis. Olfactory indicators in plants include volatile
compounds, principally represented by the terpenoid fraction. Currently, medicinal-
and adult-use cannabis is marketed in the United States with relatively little differentiation
between products other than by a common name, association with a species type, and
Δ-9 tetrahydrocannabinol/cannabidiol potency. Because of this practice, how terpenoid
compositions may change during an extraction process is widely overlooked. Here we
report on a comparative study of terpenoid and cannabinoid potencies of flower and
supercritical fluid CO2 (SC-CO2) extract from six cannabis chemovars grown in Washington State. To enable this comparison,
we employed a validated high-performance liquid chromatography/diode array detector
methodology for quantification of seven cannabinoids and developed an internal gas
chromatography-mass spectrometry method for quantification of 42 terpenes. The relative
potencies of terpenoids and cannabinoids in flower versus concentrate were significantly
different. Cannabinoid potency increased by factors of 3.2 for Δ-9 tetrahydrocannabinol
and 4.0 for cannabidiol in concentrates compared to flower. Monoterpenes were lost
in the extraction process; a ketone increased by 2.2; an ether by 2.7; monoterpene
alcohols by 5.3, 7 and 9.4; and sesquiterpenes by 5.1, 4.2, 7.7, and 8.9. Our results
demonstrate that the product of SC-CO2 extraction may have a significantly different chemotypic fingerprint from that of
cannabis flower. These results highlight the need for more complete characterization
of cannabis and associated products, beyond cannabinoid content, in order to further
understand health-related consequences of inhaling or ingesting concentrated forms.
Key words
Cannabis sativa
- Cannabaceae - cannabinoid - HPLC/DAD - GC/MS - terpenoid
