Higher Learning LV Staff
Feb 3, 20234 min
Updated: Feb 11, 2023
Welcome to the second homework assignment for Module 3: Cannabinoids 1 > Lesson 8: Review for the course Cannabis Foundation: Part 1. This assignment teaches students about the sometimes significant differences between indoor and outdoor cultivated cannabis and—more specifically—the various results of these dramatically different environments on terpene and cannabinoid profiles.
A 2023 study entitled "Comparison of the Cannabinoid and Terpene Profiles in Commercial Cannabis from Natural and Artificial Cultivation" that was published in the journal Molecules used high-tech gas/liquid chromatography and mass spectrometry to analyze "the terpene and cannabinoid profiles for commercial cannabis from genetically identical plants grown indoors using artificial light and artificially grown media or outdoors in living soil and natural sunlight."
"Until recently, cultivation and use of cannabis plants for medicinal, industrial, and recreational use were strictly prohibited and there is severely limited scientific research in this field," reported the study. It noted that the recent global wave of medical and adult-use cannabis legalization means that a better understanding of the herb's "chemical diversity is of great importance for consumers and producers."
The biochemical properties of marijuana "are derived from the plethora of secondary metabolites" that includes cannabinoids, flavonoids, terpenoids, and sterols.
The study explained that the biochemical properties of marijuana "are derived from the plethora of secondary metabolites" that includes cannabinoids, flavonoids, terpenoids, and sterols. It noted that each of these chemical categories has been identified within the flowers, leaves, stem barks, and roots of cannabis plants.
The study employed commercial cannabis samples cloned from a common parent, one of which was grown outside in natural light and in living soil and the other which was grown indoors under artificial lights. "The outdoor samples were grown in raised beds using a proprietary mixture of all-natural soil and composts under full sunlight," reported the scientists, while the indoor samples "were grown under artificial light in a proprietary growth medium."
The study tested for a relatively large set of cannabinoids, including THCA, delta-9 THC, THCV, delta-8 THC, CBGA, CBG, CBNA, CBN, CBC, CBDA, CBD, CBDVA, and CBL.
Terpenes tested involved 3-carene, α-bisabolol, α-cedrene, α-pinene, α-terpineol, α-terpinene, β-caryophyllene, β-eudesmol, β-pinene, borneol, camphene, camphor, cedrol, carene, citronel-lol, fenchol, gamma-terpinene, geraniol, geranyl acetate, humulene, fenchone, isoborneol, limonene, linalool, menthol, nerolidol, p-cymene, phytol, pulegone, and terpinolene.
The research cultivated and analyzed two commercial cultivars of cannabis, both from the 2021 growing season: Red Velvet and Cheetah Piss. Clones were acquired in California and grown in Garberville, California, in Humboldt County.
"The most common terpenes detected in both indoor and outdoor samples were BCP, humulene, and limonene—all of which were produced in greater volumes in outdoor cannabis."
The most common terpenes detected in both indoor and outdoor samples were BCP, humulene, and limonene (in order of dominance). In all three examples, the outdoor-grown marijuana produced notably greater volumes of these terpenes. However, it should be noted that, in a few cases, the indoor-grown samples produced more of a particular terpene. This was the case for alpha-pinene, borneol, fenchol, and terpineol.
"Our analyses showed significant differences in the terpene and cannabinoid profiles of two cultivars of cannabis grown in two different conditions.
"Whether the cannabis is grown indoors under artificial lights using artificial growth media or outdoors in living soil with sunlight influences the types and amounts of molecules that are present in the flowers. Indoor samples have a greater preponderance of oxidized and degraded cannabinoids and the outdoor samples are able to express more cannabinoids with potentially desirable bioactivity.
"Our analyses showed significant differences in the terpene and cannabinoid profiles of two cultivars of cannabis grown in two different conditions."
"Therefore, a comprehensive understanding of the composition of secondary metabolites, such as cannabinoids and terpenes grown in different environmental conditions, is of primary importance for the medical and recreational use of cannabis. Growing cannabis that expresses the unusual cannabinoids, such as C4- and C6-Δ9-THCA, could have significant medicinal benefit.
"There is also an important conclusion from this study revealing inadequacies in California COA testing to delineate important components of cannabis that are being sold. The lack of testing for many of the important terpenes (e.g., sesquiterpenes), cannabinoids (e.g., THCA derivatives with different length hydrocarbon sidechains), and their degradation products (e.g., CBNA) highlights the deficiency of the California COA testing.
"The ROC curve analysis using a random forest model revealed that α-guaiene, α-bergamotene, CBN, CBNDA, and CBT could serve as the top five potential predictive markers for these cultivars to discriminate the outdoor-grown from indoor ones.
"There is also an important conclusion from this study revealing inadequacies in California COA testing to delineate important components of cannabis that are being sold."
"This study is the first to evaluate the impact of natural and artificial cultivations on the profile of cannabinoids and terpenes in commercial cannabis. However, our analysis was limited by the restricted samples sizes and the limited information on the growing conditions of each cultivar in each environment.
"Further studies with larger sample sizes and different environmental conditions and breeds could enhance our understanding of the bio-chemical diversities of cannabinoids and terpenes with different medicinal and physiological properties."