by Seshata on 21/02/2014 | Medicinal

Medicinal Properties of Terpenes & Terpenoids

Plants Terpenoids and terpenes are aromatic compounds that are found in thousands of plant species, and are responsible for the various flavours and fragrances of cannabis. We have known about their presence in cannabis for decades, but it is only recently that awareness of their potential therapeutic properties has begun to expand.


Terpenoids and terpenes are aromatic compounds that are found in thousands of plant species, and are responsible for the various flavours and fragrances of cannabis. We have known about their presence in cannabis for decades, but it is only recently that awareness of their potential therapeutic properties has begun to expand.

What are terpenes & terpenoids?

Terpenes are a large class of naturally-occurring organic compounds; they are also known as isoprenes, as their structure is based on repeating isoprene (C5H8) units. Terpenes are major constituents of plant resin and essential oils extracted from such plants.

Over 120 different terpenes and terpenoids have been isolated from cannabis, and many have medicinal properties of their own
Over 120 different terpenes and terpenoids have been isolated from cannabis, and many have medicinal properties of their own

Terpenes are basic hydrocarbons, whereas terpenoids contain extra functional groups that could be comprised of a range of chemical elements. However, it is common for the term ‘terpene’ to also include terpenoids in many existing writings. Terpenoids, also known as isoprenoids, are the largest group of organic compounds found thus far, comprising at least 20,000 distinct molecules.

The isoprene rule

Limonene, which is comprised of two linked isoprene units, can be expressed as (C5H8)2, which equates to C10H16. Several other terpenes also have this structure, but the two isoprene units are arranged differently; collectively, they are known as monoterpenes (the mono- prefix refers to the number of complete terpene units; i.e. one terpene unit equals two isoprene units).

Terpenoids with three linked isoprene units are known as sesquiterpenes (sesqui- meaning 1.5), and those with four are diterpenes, and so on. The formula (C5H8)n, where n is the number of linked isoprene units, is known as the isoprene rule, and is one of nature’s most common building blocks.

The cannabis plant produces cannabinoids through a convoluted series of chemical reactions that is thought to involve terpenes as ‘building blocks’. Cannabinoids are known as terpenophenolic compounds, as they are comprised of terpene blocks attached to phenol (C6H6O) groups; as terpenes are precursors to cannabinoids, abundance of terpenes is usually a sign of high cannabinoid levels.

Which of these compounds are present in cannabis?

It is thought that cannabis contains over 120 terpenes, although many of these are found in trace amounts and may have negligible, if any, effect.

The primary terpenes and terpenoids that have been identified in cannabis are limonene, myrcene, pinene, linalool, eucalyptol, ?-terpinene, ß-caryophyllene, caryophyllene oxide, nerolidol and phytol.

These compounds, unlike cannabinoids, are not unique to cannabis (although there are now indications that other plant species do contain some phytocannabinoids) and many are in fact very familiar to us.

Limonene

Limonene is the monoterpene primarily responsible for the fragrance of citrus fruits—specifically, the D-isomer. D-limonene smells strongly orange-fragranced in its isolated form, and is in widespread use as a flavour additive in food production and an aroma compound in perfumery. It is also in use as an alternative medicine, due to its observed ability to reduce heartburn and gastric acid reflux.

Like cannabis, citrus fruits contain limonene, linalool, citral, and terpinene
Like cannabis, citrus fruits contain limonene, linalool, citral, and terpinene

As well as this, it is used as a natural, renewable solvent in cleaning products, due to its ability to dissolve oils and other lipids; it is even capable of stripping paint and is considered an effective substitute for turpentine. It must be handled with care by humans, as in high concentrations it can act as an irritant.

D-limonene is now also added to cannabis extracts as a flavour enhancer, as many of the existing terpenes are lost in processing.

Myrcene

Myrcene is another monoterpene, and is the most abundant terpene found in cannabis, making up over 60% of the essential oil of some strains. It is also found in bay leaves, wild thyme, hops, ylang-ylang, lemongrass and verbena.

Myrcene is responsible for the ‘green hop aroma’ found in dry-hopped beers (beers that have hops added post-fermentation, at low temperatures, to enhance their ‘hoppy’ flavour); the aroma itself is described as resinous, herbaceous, and slightly metallic—and very pungent at high concentrations.

Another plant that contains significant myrcene is Myrcia sphaerocarpa (Myrcia is the genus for which myrcene is named), a small shrub with astringent leaves and roots which is native to Brazil and has long been in use there as a treatment for dysentery, diarrhoea, diabetes and hypertension.

Myrcene has been demonstrated to produce analgesic effects in laboratory testing on rats; myrcene and limonene, along with the terpenoid citral (found in many citrus fruits, lemon myrtle, lemongrass and lemon verbena) have also been found to exert sedative and motor relaxant effects in mice.

Pinene

Pinene is another monoterpene, which occurs naturally as two isomers (molecules with the same chemical formula but different structures). These isomers are known as a-pinene and ß-pinene; they are usually sourced from turpentine (produced by dry distillation of coniferous wood) and make up 58-65% and around 30% of its total volume, respectively.

As well as in cannabis, both a- and ß-pinene are found in pines and other conifers, as well as in Salvia (sage), Artemisia (sagebrush), and Eucalyptus. A-pinene is also found in olive, rosemary, sassafras and bergamot; it is the most widespread naturally-occurring terpene. B-pinene is also found in hops and cumin.

A-pinene is known for its inhibitory effect on root growth in many plant species, thought to occur through the production of reactive oxygen species that cause oxidative stress within the root system; it is believed that many plant species exude it from their leaves as a natural herbicide, preventing other plants from competing against them for resources. In small doses, it also acts as a bronchodilator in humans, and exhibits anti-inflammatory, antibacterial and antibiotic properties.

Linalool

Linalool is a monoterpenoid with the chemical formula C10H18O; it is found in hundreds of plant species

including mint, laurel, cinnamon, birch, and some citrus. Linalool is a chiral molecule, meaning that it has two enantiomers, or two isomers that are non-superimposable mirror images.

Bay laurel and many related herbs contain linalool, which is a known sedative, muscle relaxant and anxiolytic
Bay laurel and many related herbs contain linalool, which is a known sedative, muscle relaxant and anxiolytic

The ‘left’ enantiomer is known as S-linalool, is found in coriander, palmarosa grass and sweet orange, and has a sweet, floral scent; the ‘right’ enantiomer is known as R-linalool, is found in lavender, basil and bay laurel, and has a woody, astringent aroma.

Linalool’s main medicinal function is as an anxiolytic—an anxiety-reducing drug. Lavender has been in use as a calmative for thousands of years, and recent tests on rats have borne out its sedative and motor relaxant effects.

Other terpenes & terpenoids in cannabis

Eucalyptol, a monoterpenoid, is abundant in nature. As well as in cannabis, it is found in eucalyptus, tea tree, bay leaves, basil and sage; it is well-known for its antiseptic, antibacterial and anti-inflammatory properties.

G-terpinene, a monoterpene found in various citrus fruits and herbs such as oregano and marjoram, is known to have antioxidant properties; phytol, a diterpenoid, is used by insects as a deterrent to predators, and is also used in various household products such as detergents and soaps.

D-limonene is now often added to solvent extracts to enhance flavours lost during processing
D-limonene is now often added to solvent extracts to enhance flavours lost during processing

B-caryophyllene, a sesquiterpene found in cloves, rosemary and hops, exhibits anti-inflammatory effects and has been demonstrated to act as a selective agonist of the CB2-receptor (no other terpenes or terpenoids have been found to affect the CB receptors). Caryophyllene oxide is the substance in cannabis that is identifiable by drug-sniffing dogs.

Nerolidol, present in neroli, ginger and jasmine, is a sesquiterpenoid with a fresh, woody scent; it is currently being investigated both as a facilitator for transdermal delivery of drugs (due to its ability to penetrate the skin) and as an inhibitor of Leishmania protozoa.

Differences between types of cannabis

Of course, terpene and terpenoids concentration will vary between strains, between related individuals, and even between two clones of the same individual, if subject to different environmental conditions while growing.

Cannabis, hops, rosemary and cloves all contain ß-caryophyllene, the only terpene known to affect the cannabinoid receptors
Cannabis, hops, rosemary and cloves all contain ß-caryophyllene, the only terpene known to affect the cannabinoid receptors

However, researchers have noted that plants of the wide-leafed Afghani Cannabis indica type are more likely to contain high ratios of guaiol, isomers of eudesmol, and other unidentified compounds; plants of the narrow-leafed C. indica type that is indigenous to the valleys of the Himalayas are higher in transß-farnesene.

Guaiol is a sesquiterpenoid found in cypress and Guaiacum (a genus of five slow-growing shrubs and trees native to the tropical Americas); guaiacum itself has been in use as a treatment for coughs, arthritis and syphilis for centuries. Eudesmol, another sesquiterpenoid, is used as a fixative in perfumery, while transß-farnesene acts as a natural insecticide in many plant species, including potatoes.

The health benefits of these compounds are not fully understood, but they may contribute to the differences in medicinal properties found between the different subtypes of cannabis. As our understanding grows, so too will knowledge of how best to develop and utilise new medical strains.

Comment Section

Post a comment

Nebula

Great article about terpenes & terpenoids, thanks for sharing this!

23/02/2014

thegreengrower

A very informative and interesting article. Always a pleasure to read about positive attitudes towards the properties of cannabis, and in the way it may be able to benefit the use of cannabis for medicinal purposes.

24/02/2014

anti inflammatory capsules

We are a bunch of volunteers and starting a new scheme
in our community. Your site provided us with useful information
to work on. You've done an impressive process and
our entire community shall be thankful to you.

25/02/2014

Alamgir,ANM

Very informative and useful

10/05/2014

kato hannington

good literature

22/07/2014

David Watson

You should say what terpenes are useful for what type of effects?
Limonene for up, Myrcene for couchlock for example.
And there are 140 terepenes found in Cannabis that they have ID'ed so far, email me and I will send you the list.
I tried the top 12 terpenes one at a time, with 25mg pure THC with Rob Clarke.
You have just scratched the surface of terpenes.

03/10/2015

Chris

Hey David,

I would love to learn more about all the terpenes in cannabis and your experiences. Could you email me the list, when you have a second. I would love to share this info with my patients.

Thanks in advance.

Chris
chris@greenwaydoctors.com

06/03/2016

nancy

David- I would love to hear more about what you are doing and have done with profiling terpenes....

n.netherland@medicann.com

05/04/2016

Dan

Hi David,

If you're willing to share, I'd also love to hear more about what you're up to.

Thanks,
Dan

22/07/2016

David

I would love to hear more about what you are doing and have done with profiling terpenes

16/02/2017

Jegason

I'm a lab manager at a cannabis testing facility. I would find the list of terpenes to be extremely useful for our clients.

Please email me if you get a chance. I sure appreciate it!

17/04/2017

Marc

I have visited the Greek island of Kefaloni three times and on each visit have notice a strong 'cannabis' type smell along the roadside. On my last visit I manage to identify the plant that was producing the aroma. It was a lush green and had clumps or clusters of what I imagine were seed pods of some sort. Unfortunately I couldn't keep my sample.
Have you any idea what this plant may be? Are hops, tea and cannabis related by the same aromatic compounds and is this compound found naturally in other species?

07/10/2015

Shehryar

It provides a clear cut view about terpenoids.

27/06/2016

Emmanuella

What is the work of terpenoid in Annona muticata

03/09/2016

Scarlet Palmer

Hello Emmanuella,

Thank you for your comment. I'm afraid we cannot answer that question as the plant you refer to (I think you mean Annona muricata?) is not covered in this article, and is not a member of the cannabis family. Sorry we can't be more help!

With best wishes,

Scarlet

07/09/2016

lydia

would like to know the modern methods of extraction and separation of terpenoids

28/10/2016

Alan Luck

Great article - I have been using terps for about 2 years now, I buy them from Kleanterpenes.com in the Aroma section. I use alpha pinene, limonene and citral in an aromatherapy diffuser in the morning to wake up (i'll use an e-pen mixed with propylene glycol if I'm especially tired). I use myrcene, linalool and one of terpineol, terpinene or terpinolene at nighttime before I go to bed and it keeps me out all night. I add nerolidol if I'm having a lot of trouble sleeping, or maybe I add linalool and myrcene to a sock and put it under the covers. All this said, these are concentrated aromatics and certain ones can irritate the skin, or the eyes, or like linalool is therapeutically anxiolytic at 1ppm in the air but is toxic at 20ppm. When I first started I took too much and turned my right arm red for 2 days with a rash. Not to mess around with, don't drink it and don't take a bath in it. Pinene as another example is only shipped ground because it is as flammable as pure alcohol. Don't light a match around it, but breathing small amounts improves lung function and can even kill the most stubborn lung infection. These same compounds have anti-cancer activity, so the person with the herb garden in King. Sage, Rosemary, Dill, Thyme, etc all have these compounds. I currently mix custom flavors for people to add to bong water or diffusers for non-cannabis people. Long live terpenes!

27/11/2016

Terpenes and Testing Magazine

Great article, lots of informative material,Very nice work , thank you for the information

Thanks,
Terpenes and Testing Magazine

14/04/2017

Leave a Comment

Please enter a name
Oops, looks like you forgot something?