What are Terpenes?
Terpenes - What You Need To Know
by Dr Linda Klumpers
That which we call a rose by any other name would smell as sweet. Be it a flower or a fruit - by the smell alone can you distinguish a rose from a lily and an orange from a lime. Similarly, cannabis plants have distinct aromas, which are often related to their naming: think of super lemon haze or cheese. Most of the aroma in fruit, flowers, cannabis, and other plants comes from oily compounds chemically classified as terpenes or terpenoids (modified terpenes with additional elements and chemical groups). For simplicity, we will combine both groups in this article and call them terpenes.
The number of terpenes that exist is enormous. Thousands of them are found in nature. Cannabis plants produce more than 100 different terpenes alone. Of these, less than a dozen are prominently present, while the rest are only produced in very small amounts.
Why do plants make terpenes?
Although it is not entirely clear why a plant makes terpenes, scientists believe that there are several reasons. For example, a plant can guide insects their way for pollination purposes. The antimicrobial workings of terpenes lead us to think that plants use them to guard against pathogens. Other terpenes repel herbivores, potentially protecting the plant’s reproductive parts from its enemies. This last assumption may be applied to the cannabis flower, which contains reproductive organs and produces a highly aromatic terpene smell.
Furthermore, terpenes might play a role in communication between plants. (Reinhard et al., 2004; Dudareva et al., 2004) In some plants, terpenes can play a role in photosynthesis and coloring agents. (McCreath et al., 2017)
Why do cannabis products contain terpenes?
With the flowers having the strongest smell of the plant, they contain the highest amount of terpenes. The terpenes are produced and stored by a certain type of trichomes (glands on a plant that appear hairy or frosty) and the cells around it. These hairy structures are called capitate sessile trichomes and are believed to play a role in cannabis’ defense. (Pertwee, 2014)
Raw cannabis flowers always come with terpenes. The terpenes are often an important factor in choosing a product: people like buying good smelling products! When converting a cannabis flower into any CBD product, the oils are extracted from the flower, and, depending on the extraction method that is used, terpenes are left in the CBD oil. The vernacular for this type of terpene and cannabinoid-rich extract is “full spectrum”. Full-spectrum extracts and the products made from them maintain as much as possible of the cannabinoid and terpene profile of the original flower.
All Green Earth Medicinals products are made from full-spectrum extracts.
Various manufacturers like to keep the terpenes in their CBD oil for a variety of reasons, but smell and the way they make people feel are the most important.
How do terpenes make you feel?
Terpene smells are associated with certain experiences and feelings. Cleaning agents contain citrus fragrance for a feeling of cleanliness. Toothpaste has mint to make your mouth feel fresh.. Spices like cinnamon and cloves give a feeling of warmth and are used in cold seasons’ food and beverages, such as apple ciders. The list of associations is long, and behind all these fragrances are mixtures of terpenes, often with a few of them dominating.
The question then becomes whether there is something that goes beyond all these experiences and associations; do terpenes truly have effects on our body? They do! At the same time, however, we also need to place an important marginal comment here: there are a lot of unknowns. Nonetheless, you might have read or heard anecdotally that people report on terpenes from different cannabis cultivars to give different effects. Scientifically, however, this has not been proven, although studies to understand more about this topic are ongoing.
Do products from Green Earth Medicinals contain terpenes?
Yes! While many CBD oil products on the market contain varying terpene levels that come solely from cannabis concentrates, Green Earth Medicinals has a different approach. Working with botanicals, one needs to make a fine balance between the varietal richness of naturally occurring constituents that can be different from plant to plant, and even from flower to flower (look at your rose bush or coneflowers: do any two flowers of the same plant look the same?), versus keeping your product consistent on the other hand. With consistency, Green Earth Medicinals refers to a predictable product that has the same levels of terpenes and other major constituents every time.
To be able to control the terpene level, Green Earth Medicinals applies chemical analyses for understanding the total terpene content of each cannabis cultivar’s CBD oil and balances the content they want by adding terpenes from natural sources, such as compounds from tangerine, eucalyptus, and lavender. (Poole, 2020)
Which terpenes can I find in products from Green Earth Medicinals?
Every product by Green Earth Medicinals contains a different set of terpenes, and each was added by Green Earth Medicinals with a different intention, but what do we know about terpenes from the scientific literature? We will discuss two of them:
Limonene
When examining the ingredient list of Green Earth Medicinals’ products (for example, here), you will see the following: “Tangerine to enhance absorption”. Tangerine oil contains a terpene mixture with limonene as a dominant terpene (Figure 1). Limonene is a common terpene for citrus fruits as well as for cannabis, and various animal studies have shown that it enhances skin permeability for various compounds, helping them to be absorbed through the skin more efficiently (more information in our absorption and bioavailability post). (Krishnaiah et al., 2008) Also, effect properties are believed to be induced by limonene, and some people believe that there might be an interaction with the cannabinoid THC. This interaction is currently (in 2020) being studied in a clinical trial.
Eucalyptol
Eucalyptol, also known under its splendid name 1,8-cineole, is a major terpene from the oil of a eucalyptus tree that binds to pain-regulating receptors (Figure 2). (Takaishi et al., 2008; Zhang et al., 2018) Animal studies have found that eucalyptol is pain-relieving, but evidence from human studies is lacking. (Zhang et al., 2018) Eucalyptol has also been studied for its beneficial effects in asthma and anxiety. These studies are preliminary and more research is needed to draw any conclusion. (Juergens, 2014; Kim et al., 2014)
Lavender, spearmint, hops… There is so much more to write about the dominant terpenes from the botanicals that Green Earth Medicinals uses in their products. Make sure to stay tuned for more terpene news in future blog posts!
Highlights
- Plants produce aromatic compounds called terpenes
- Cannabis plants produce more than 100 different terpenes
- CBD products often contain terpenes that are naturally occurring in the cultivar that they were extracted from
- Terpenes can influence and improve the absorption of other compounds
- Terpenes can give effects too, but this needs to be further researched to make hard conclusions
We are now working with our friends at Cannify to bring you more information on important topics. Cannify researches and educates about cannabis. It is the first company to match patients and products with science. Cannify's founder Dr. Linda Klumpers earned a Ph.D. in Clinical Pharmacology of cannabis and has been studying cannabis for over a decade. Cannify educates an audience that includes patients, healthcare providers, and university students, and is actively involved in various cannabis-related research projects.
References
- Reinhard, Judith, Mandyam V. Srinivasan, and Shaowu Zhang. "Scent-triggered navigation in honeybees." Nature 427, no. 6973 (2004): 411-411.
- Dudareva, Natalia, Eran Pichersky, and Jonathan Gershenzon. "Biochemistry of plant volatiles." Plant physiology 135, no. 4 (2004): 1893-1902.
- McCreath, Simone Badal, and Rupika Delgoda. Pharmacognosy: Fundamentals, applications and strategies. Academic Press, 2017. Chapter 11
- Pertwee, Roger G., ed. Handbook of cannabis. Oxford University Press, USA, 2014. Chapter 4
- Poole, Haley, personal communication with regards to the production procedures of Green Earth Medicinals, July 2020.
- Krishnaiah, Yellela S, and Saleh M Al-Saidan. “Limonene enhances the in vitro and in vivo permeation of trimetazidine across a membrane-controlled transdermal therapeutic system.” Current drug delivery vol. 5,1 (2008): 70-6. doi:10.2174/156720108783330970
- Takaishi, Masayuki et al. “1,8-cineole, a TRPM8 agonist, is a novel natural antagonist of human TRPA1.” Molecular pain vol. 8 86. 29 Nov. 2012, doi:10.1186/1744-8069-8-86
- Zhang, Ya-Ling et al. “1,8-cineole decreases neuropathic pain probably via a mechanism mediating P2X3 receptor in the dorsal root ganglion.” Neurochemistry international vol. 121 (2018): 69-74. doi:10.1016/j.neuint.2018.09.007
- Juergens, U R. “Anti-inflammatory properties of the monoterpene 1.8-cineole: current evidence for co-medication in inflammatory airway diseases.” Drug research vol. 64,12 (2014): 638-46. doi:10.1055/s-0034-1372609
- Kim, Ka Young et al. “The effect of 1,8-cineole inhalation on preoperative anxiety: a randomized clinical trial.” Evidence-based complementary and alternative medicine : eCAM vol. 2014 (2014): 820126. doi:10.1155/2014/820126
- Pubchem, accessed in July 2020, https://pubchem.ncbi.nlm.nih.gov/compound/440917
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