Terpenes, or isoprenoids, provide cannabis with its unique bouquet. The molecules are quite small and consist of repeating units of a compound called isoprene. Although less well known than the major cannabinoids, terpenes are instrumental to the physiological and psychoactive effects of cannabis. The relationship between terpenes and cannabinoids, known as the “entourage effect,” ultimately differentiates one strain of cannabis from another.
Terpenes play a vital role in the plant kingdom; they deter insect predation, protect plants from environmental stresses, and act as building blocks for more complex molecules, such as cannabinoids. Many terpenes act synergistically with other varieties of terpenes, and some either catalyze or inhibit formation of different compounds within a plant. Understanding how terpenes function allows scientists to manipulate cannabinoids to desired ratios.
Primary Terpenes Found in Cannabis
α Pinene accounts for cannabis’ familiar odor, often associated with pine trees and turpentine. α Pinene is the most common naturally occurring terpenoid and acts as both an anti-inflammatory and a bronchodilator.
Myrcene is the most prevalent terpene and is found in most varieties of cannabis. Myrcene concentration dictates whether a strain will have an Indica or Sativa effect. Strains containing over 0.5% of myrcene produce a more sedative high, while strains containing less than 0.5% myrcene have an energizing effect. Myrcene is also present in thyme, hops, lemongrass, and citrus, and is used in aromatherapy.
Limonene is a dominant terpene in strains with a pronounced Sativa effect. It is also found in the rinds of citrus fruits. Limonene aids in the absorption of other terpenes through the skin and mucous membranes, and has been used to treat anxiety and depression.
Ocimene is frequently used in perfumes for its pleasant odor. In nature, this terpene contributes to a plant’s defenses and possess antifungal properties.
Terpinolene has been shown to exhibit antioxidant and anticancer effects in rat brain cells. Studies with mice show that terpinolene has a sedative effect when inhaled. In addition, terpinolene is responsible for many of the floral notes found in Jack Herer varieties.
Terpineol is known for its pleasant smell and is often used in soaps and perfumes. It is known to have relaxing effects.
Valencene is present in Valencia oranges and contributes to cannabis’ citrus aroma.
β Caryophyllene is the only terpene known to interact with the body’s endocannabinoid system (CB2). It produces anti-inflammatory and analgesic effects.
Also present in geraniums, geraniol emits a rosey scent that makes it a popular perfume additive. It is an effective mosquito repellent and shows a potential protective effect against neuropathy.
α Humulene contributes to the “hoppy” aroma of cannabis. This terpene acts as an appetite suppressant and exhibits potent anti-inflammatory activity.
Secondary Terpenes Found in Cannabis
Phellandrene:Phellandrene is commonly found in the essential oil of plants in the eucalyptus genus. Its smell is reminiscent of peppermint, with a slight citrus tone. Recent research shows that phellandrene possesses antidepressive effects.
Carene:Carene has a sweet, pungent odor and is a main constituent of pine and cedar resin. It is used to dry out excess body fluids, such as tears, mucus, and sweat.
Terpinene:Terpinene is used as a fragrant additive in both the cosmetic and food industries.It is also considered to be a well-tolerated additive in the pharmaceutical industry. It has very strong antioxidant properties.
Fenchol:Fenchol is found in basil and is used extensively in perfumery. It is known to exhibit antibacterial properties.
Borneol:Borneol has a menthol aroma and is used as a calming sedative. It is also beneficial for combating fatigue and recovering from stress or illness. Borneol exhibits both anti-inflammatory and anti-nociceptive effects.
Bisabolol:Bisabolol is the primary constituent of German chamomile essential oil and has recently been shown to induce apoptosis in models of leukemia.
Phytol:Found in green tea, phytol is a diterpene that results from the degradation of chlorophyll. Phytol inhibits the enzyme that degrades the neurotransmitter GABA, which may partially account for its relaxing effect.
Camphene:Camphene is found in essential oils extracted from certain trees. It has recently shown promise for pain relief and antioxidant effects.
Sabinene:Sabinene is known for its spicy, oak, and black pepper accents. It has been shown to benefit liver function and digestion, relieve arthritis, and can soothe skin conditions.
Camphor:Principally derived from the camphor tree, camphor is readily absorbed through the skin. When applied topically, it produces a cooling sensation similar to that of menthol. Camphor also acts as a slight local anesthetic and an antimicrobial substance.
Isoborneol:Isoborneol is found in mugwort that exhibits antiviral properties. It is a potent inhibitor of herpes simplex virus type 1.
Menthol:Menthol exhibits analgesic properties and is used topically to treat inflammatory pain.
Cedrene:Cedrene is present in the essential oil of cedar.
Nerolidol:Nerolidol is found in oranges. It acts as a sedative and exhibits potent antifungal and antimalarial activity.
Guaiol:Guaiol is an alcohol found in the oil of guaiacum and cypress pine. It possesses antimicrobial properties.
Isopulegol:Isopulegol is a chemical precursor to menthol, and has a variety of promising routes for therapeutic research. Studies have shown that isopulegol possess gastroprotective and anti-inflammatory effects, and reduces the severity of seizures in animal models.
Geranyl Acetate:Geranyl Acetate is found in a variety of natural oils, derived from citronella, lemongrass, sassafras, roses, and many others. It has a strong floral aroma with a fruity twist, and exhibits strong antimicrobial effects.
Cymene:Commonly found in the essential oils of cumin and thyme, cymene has documented anti-inflammatory effects. Research also shows potential protective effects against acute lung injury.
Eucalyptol:Derived from eucalyptus oil, eucalyptol has a minty, earthy aroma. It has been shown to possess potent antifungal effects.
Pulegone:Pulegone has a pleasant peppermint aroma and is a strong insecticide.