There are many other compounds other than cannabinoids found inside hemp that are both biologically active, and flavorful and fragrant. These are known as terpenoids, or terpenes, and are extremely common chemical compounds found in most plants and some animals, and serve to function as important biosynthetic cellular messengers. A large amount of hormones, including estrogens, are in fact, terpenoids, and they have the same basic organic chemical structure.
You may not know this, but all cannabinoids are chemically classified as terpenes, but these cannabinoids are found in cannabis alone. In this article we’ll be covering terpenes commonly found in cannabis and other plants.
Terpenes are unique oils which are secreted by glandular hairs found most commonly on floral leaves and the flowers of female plants. The particular smell and flavor of the terpene helps to identify the strain along with their known health effects. Grapefruit, lemon, pine and lavender are often used to describe the taste or smell of different varieties of hemp.
We will switch between using the terms “hemp” and “cannabis” somewhat interchangeably, in that cannabis refers to all varieties of the plant, such as hemp and marijuana, whereas referring to hemp alone refers to industrial hemp; the variety of cannabis with negligible levels of THC (less than 0.3%) and best known for its many industrial uses and herbal remedies.
The terpene found most abundantly in hemp is the terpene myrcene. In some varieties of hemp, it can make up 60% of the essential oils. Indica strains that have above 0.5 percent levels of myrcene can cause sedation. The aroma of myrcene has been described as earthy, musky, and herbal, somewhat similar to cloves. There are several varieties of plants whose oils contain myrcene such as citrus fruits, hops, eucalyptus, bay leaves, wild thyme, and lemongrass, along with many other plants.
Myrcene has unique medicinal properties. It has been found to be a sedative and muscle relaxant. It works to lower the resistance across the blood-brain barrier, which allows it and other chemicals to cross the barrier more rapidly. Myrcene also allows the effects of cannabinoids like THC to take effect more quickly. Myrcene also has the ability to increase the saturation level of the CB1 receptor, which can then maximize the psychoactive effect of tetrahydrocannabinol (THC) in cannabis.
Myrcene works as a strong analgesic (pain killer), antibiotic, anti-inflammatory, and antimutagenic, which can also block the action of cytochrome and other mutagenic carcinogens. A study from 2014 found that myrcene can act as an inhibitor of gastric and duodenal ulcers with researchers suggesting it could assist in preventing peptic ulcer disease. Myrcene’s relaxing sedative effects make it a viable option for those wishing to alleviate symptoms of insomnia and pain.
Cannabis plants grown with high levels of limonene often have very strong citrus odors like lemons, oranges and limes, and tend to promote an uplifting mood and attitude. Considered a monocyclic monoterpenoid, limonene is one of two major compounds formed from the terpene, pinene, and is an important compound found in citrus fruit rinds, juniper, rosemary, and peppermint, along with several pine needle oils.
Limonene is rapidly absorbed into the bloodstream after inhalation. It assists in the absorption of other terpenes through the skin and other body tissue. Limonene makes for the perfect anti-fungal for conditions such as toenail fungus, as it has the ability to suppress the growth of many species of bacteria and fungi. Limonene may have benefits in protecting against various cancers, with research showing it reversed mammary tumors in mice and stimulated apoptosis (when rogue cells in the body are programmed to die), in breast cancer tissue. It has also been shown to help aid in weight loss.
Limonene is a natural insecticide that plants use to ward off predators, and, while its main use was in perfumes and food until a couple of decades ago, it’s not best found to be used as the primary active ingredient in citrus cleaner as it has a very low toxicity or adverse effects on human health.
Testing on the effects of limonene have been carried out with participants experiencing an increase in attention, mental focus, well-being and even sex drive. Limonene can prevent the breakdown of the RAS gene, one of the factors that contributes to the development of tumors, and protects against aspergillus and carcinogens present in smoke.
Beta-caryophyllene is found in Thai basil, clove, cinnamon leaf, lavender, and black pepper, and has a peppery, woody, and/or spicy aroma. Research shows that caryophyllene may be effective in cancer treatment plans. It's also one of the only known terpenes to interact directly with the endocannabinoid system. Studies are showing that caryophyllene binds to the CB2 receptors and that it is a functional CB2 agonist. Caryophyllene is a highly functional non-psychoactive CB2 receptor ligand in foodstuff and a macrocyclic anti-inflammatory cannabinoid in hemp.
In 2012, medical researcher suggested that caryophyllene could make an excellent therapeutic agent to prevent nephrotoxicity (impacting the kidneys) caused by anti-cancer chemotherapy drugs like cisplatin when delivered through a CB2 receptor pathway. In that same year, another study focused on the chemical composition and pharmacological properties of essential oil isolated from black pepper, of which caryophyllene is a main constituent. It was discovered to have anti-inflammatory, antinociceptive, and antioxidant qualities. Hemp strains high in this terpene, may be of value in assisting with pain related to neuropathy and arthritis.
In 2013, a study found the combination of phytocannabinoids, specifically cannabidiol (CBD) and beta-caryophyllene, administered orally, appears to be a potential treatment for chronic pain. The hemp variety of cannabis often naturally contains high-CBD and low-THC levels.
Pinene is considered to be a bicyclic monoterpenoid, possessing aromas of fir and pine. The two structural isomers of pinene can be found in nature (alpha-pinene and beta-pinene), both of which are important components of pine resin. In fact, this terpene is nature’s most abundant terpenoid, found mainly inside balsamic resin, pinewoods, and some citrus fruits, as well as many other conifers and non-coniferous plants. The two isomers constitute the main component of wood turpentine. Pinene is a principal monoterpene, important physiologically in both plants and animals, and tends to react with other chemicals, forming other terpenes, such as limonene, and other compounds.
Pinene has been used as a local antiseptic and an anti-inflammatory expectorant. It is also thought to be a bronchodilator. Plants rich in pinene give off a smoke sensation of sucking more air, which can cause hyperventilation or sometimes cough. Alpha-pinene can be isolated from pine needle oil and is a natural compound that has shown anti-cancer properties. In Traditional Chinese Medicine, it has been used as an anti-cancer agent. Tetrahydrocannabinol (THC) effects may be reduced when combined with this terpene.
Pinene can easily cross the brain barrier to help prevent the destruction of molecules responsible for the transmission of information, which results in an improvement in memory function. Sage and rosemary have been considered advantageous to human health for thousands of years in traditional medicinal practices partly due to their makeup of pinene. It can counteract the effects of THC and improve concentration. Memory lapses seem to occur more often with the use of pure THC versus THC mixed with pinene. The solution then, would be to utilize a variety of cannabis grown with balanced levels of both THC and other terpenes.
There are three very closely related monoterpenoids, they are; alpha-terpineol, 4-terpineol, and terpinen-4-ol, and have aromas that closely resemble that of flower blossoms and lilacs. These compounds are often found in varieties of hemp that are also high in pinene, though, the fragrances of terpineol are often overpowered by other more redolent terpenes. Alpha-terpineol has been found to have relaxing, calming effects and shows antioxidant, antimalarial, and antibiotic properties. It is also known to have anti-inflammatory, anti-tumor, anxiolytic, and sedative properties.
Varieties of hemp that contain high levels of the non-cyclic monoterpenoid linalool promote relaxing, calming effects. Linalool has lavender and floral undertones and for a millenia, has been utilized as a sleeping agent. Linalool seems to reduce the anxiety that pure THC can bring on, making it useful in treating anxiety and psychosis.
One particular research paper suggested that linalool may greatly reduce lung inflammation brought on by cigarette smoke. It may stop the carcinogenesis aggravated by benz(a)anthracene, a component of the tar generated by the combustion of tobacco.
Linalool has the ability to activate immune cells through specific receptors and/or pathways and may actually boost the immune system in general. Studies have shown that the anti-inflammatory effect of linalool can contribute to the slowdown and reversal of Alzheimer’s disease.
The Environmental Protection Agency (EPA) has approved its use as a flavor agent, pesticide and scent. Linalool’s vapors seem to be a very effective insecticide to ward off fleas, fruit flies, and cockroaches.
Delta-3-carene is a bicyclic monoterpene with a sweet, pungent odor. Found in higher concentrations, it can work as a depressant in the central nervous system. It also contains natural anti-inflammatory properties. Found in many essential oils such as juniper berry oil, fir needle, and cypress oil, this terpene is used to dry out the body’s excess fluids, such as mucus, sweat and tears. Though it is considered to be non-toxic, it may cause irritation when inhaled. Cannabis that contains high concentrations of delta-3-carene may partially cause symptoms of itchy throat, coughing and eye irritation when smoked. Delta-3-carene can be found in bell pepper, pine extract, basil oil, orange juice, grapefruit, and citrus peel oils from fruits like lemons, mandarins, limes, oranges, tangerines, and kumquats. Carene is a major component of turpentine.
Terpinolene is a commonly found terpene in rosemary, sage and Monterey cypress oil. Terpinolene is used largely throughout the US in perfumes and soaps, and is a well-known and highly-regarded insect repellent. With a piney aroma and hints of flora and herbs, terpinolene has a sweet flavor of orange and lemon citrus.
One research paper on terpinolene discovered that it can reduce anxiety and act as a sleep aid. Another paper found that it greatly reduced the protein expression of AKT1 in K562 cells, inhibiting the cell proliferation involved in a variety of cancers.
Phellandrene is a peppermint-scented terpene with a hint of citrus, and is possibly the easiest terpene to identify in a science-based setting. Dill and pepper oil are composed almost entirely of phellandrene, and it’s also the principal constituent in oil of ginger. Phellandrene has been utilized in Traditional Chinese Medicine to treat digestive disorders and is a primary compound in turmeric leaf oil, which has been commonly used to help prevent and treat systemic fungal infections. This is another terpene of great value due to the fact that cannabidiol (CBD), also found in cannabis, has anti-bacterial and anti-fungal effects.
Humulene is a sesquiterpene and can be found in strains of Cannabis sativa, hops, and Vietnamese coriander, often giving beer its distinct “hoppy” aroma. Humulene is thought of as an anti-tumor, antiinflammatory, antibacterial, and anorectic (appetite suppressant). In Chinese medicine, It is often blended with caryophyllene as a powerful remedy to treat chronic inflammation.
Nerolidol has distinctive fresh bark and woody aromas, found in citronella and ginger. It contains strong antimalarial and anti-fungal properties, and also produces sedative effects.
Alpha bisabolol can be found in chamomile and has been used for a long time in the cosmetics industry. It comes with a floral aroma, with its medicinal uses including the healing of wounds, and as a deodorizer. Alpha bisabolol is shown to be effective in treating various kinds of inflammation, along with having antimicrobial, analgesic, antibacterial, antioxidant, and anti-irritant properties.
B-Elemene has a medium strength, sweet aroma. The most concentrated form of B-elemene is isolated from a form of ginger called rhizoma zedoariae. It is a rather volatile terpene found in botanical plants such as mint and celery, and it is also prevalent in a multiple of medicinal plants. It has effective anti-cancer and anti-proliferative effects against a wide range of tumors.
a-Eudesmol comes with a sweet, woody odor. It has been shown to protect against brain injury after focal ischemia in rats. Recently, a-eudesmol has shown signs it may become useful for the treatment of migraines.
Valencene is a sesquiterpene that was given its name after the fruit in which it is most commonly found, Valencia oranges. Its sweet, citrusy flavors and aromas can be reminiscent of grapefruits, oranges, tangerines and the occasional fresh herbs or freshly cut wood. This very fragrant terpene is responsible for the familiar citrus aromas often found in a large variety of cannabis strains. It is an antifungal, antiinflammatory, and effective insect repellent.
As cannabis products rapidly expand in the marketplace, we'll see greater use of terpenes due to their ability to enhance the effects of the many of the 120+ cannabinoids such as CBD, CBG, CBN, CBDA, and THCA.