Taken from Ed Rosenthals Big Book of Buds 3
Chemically speaking,
terpenes are composed of repeating units of isoprene, which is a five carbon unit chain or ring with eight hydrogen atoms attached(C5H8).
Terpenes use the simple isoprene units as blocks to build 10, 15, 20 and 30 carbon units(these are called, respectively, the C10-monoterpenoid, C15 sesquiterpenoid, C20-diterpenoid, C30- triterpenoid) and can twist and turn the molecular structure to form simple chains or three-dimensional (polycyclic) structures. In addition,
terpenes can form bonds with other molecules, which affect how animals and plants react to them. Depending on how they stack against each other, they form different aromatic compounds.
Most of the aromas that we associate with plants are the results of
terpenes and flavonoids. Humans can smell and taste these compounds, but that is not the only ways that they affect us. Aromatherapy uses inhaled essential oils to regulate mood, sleep paterns, acuity and the healing process. Lavender oil is a soothing agent and relaxant; rosemary is used to focus attention and provide a sense of satisfaction. These effects are a result of the combination of
terpenes and other chemicals found in the oils of these plants. While
terpenes affect the brain in their own way, they also modify the effect of THC within the brain, adding subtleties to the high.
Some
terpenes may affect the high in this way because they lock into receptor sites in the brain and modify its chemical output. A few, such as thujone, one of the main
terpenes in wormwood(used to make absinthe), bind weakly to the CB1 receptor. Others may alter the permeability of cell membranes or the blood brain-barrier, and allow in either more or less THC. Others affect serotonin and dopamine chemistry (neurotransmitters) by shutting off their production, affecting their movement, binding to their receptor sites, or slowing their natural destruction.
Dopamine and serotonin, two of the main regulators of mood and attitude are affected by some
terpenes.
By tempoarily altering brain function,
terpenes can affect mood, sensitivity, and perception of the senses as well as bodily perceptions such as balance and pain. When
terpenes are mixed as they are in natural plant oils, they each play a rolein affecting brain function. Some combinations may work synergystically and others antagonistically, but each "recipe" affects moods and feelings in its own way.
Over 100
terpenes have been identified in marijuana. Ther are actually many more when one considersmultiple variations of each terpene. For instance, the characteristic citrus odor found in fruit rinds differ by type and even variety of fruit- oranges and lemons have different odors, and their
terpenes called -limonenes- are mirror versions of each other. Even different varieties of oranges differ in their distinct odor. This is due to slight differences in the amounts of or form of
limonene, as well as other compounds that have citrus elements.
About 10-29 percent of marijuana smoke resin is composed of
terpenes. Some
terpenes present in marijuana appear only occasionaly in samples while others are found all the time. The percentage of
terpenes and the ratios in which they are found vary by plant variety. You can experience this yourself as different varieties have different smells, indicating a different essential oil makeup.
Age, maturation and time of day of harvest can affect the amount and perhaps ratios of
terpenes. As plants mature, their odor gets more intense and often changes as they ripen. Climate and weather also affect terpene and flavonoid production. The same variety(even genotype) produces different quantities and perhaps different oils when grown in different soils or with different fertilizers.
Terpenes are constantly being produced but they evaporate under pressure from sunlight and rising temperatures. Plants have more
terpenes at the end of the dark period than after a full day of light.(just one of the reasons its better to harvest early morning after a full nights darkness) You can test this yourself. Check a plants odor early in the morning and at the end of a sunny day. You will find more pungency early in the morning.
Hops and both grouos of cannabis lowTHC hemp and marijuana, contain similar complements of
terpenes. One researcher found that the oil of common black pepper(piper nigrum) has a similar group of
terpenes as Cannabis.
Terpenes are produced in the trichomes, the same glands where THC is produced. They comprise between 10 and 20 percent of the total oils produced by the glands.
The most abundant
terpenes in marijuana are described below in general order of abundance. Individual samples may differ widely, both in total percentages of
terpenes and in their ratios.
Myrcene is the most prevalent terpene found in most varieties of marijuana but not found in hemp. It is also present in high amounts in hops, lemon grass, East Indian bay tree, verbena and the plant from which it derives its name mercia.
Myrcene appears in small amounts in the essential oils of many other plants.
Its odor is variously described as clove like, earthy, green-vegatative, citrus, fruity with tropical mango and minty nuances(In fact,
myrcene is found in large qauntities in cavalo, rosa, espada, and paulista mangos). The various odors are the result of slight differences in the overall esential oil makeup. All of these flavors and odors are commonly used to describe Cannabis.
Myrcene is a potent analgesic, anti-inflammatory and antibiotic. It blocks the actions of cytochrome, aflatoxin B and other pro-mutagens that are implicated in carcinogenesis. It is present in small amounts in many essential oils associated with anti-depressive and uplifting behavior.
Myrcene is probably a synergist of THC: A combination of the two molecules creates a stronger experience than THC alone.
Myrcene probably affects the permiability of the cell membranes, thus it may allow more THC to reach brain cells.
LIMONENE is found in the rinds of citrus and many other fruits and flowers. It is the second, third or fourth most prevalent terpene in cannabis resins. Everyone is familiar with the odor of citrus resins. They explode into the air when a fruit is peeled. The exact order is determined by the structure of the terpene.
Limonene has anti-bacterial, anti-fungal and anti cancer activities. It inhibits the ras cancer gene cascade, which promotes tumor growth. It is used to synergistically promote the absorbtion of other
terpenes by penetrating cell membranes.
Limonene sprays are also used to treat depression.
Since
Limonene is such a potent anti-fungal and anti-cancer agent, it is thought to protect against aspergillus fungi and carcinogens found in cannabis smoke streams
.
Plants use
Limonene to repulse predators. For instance, flies have a group of receptors similar in function to the taste buds on our tongues. One of them detects noxious chemicals, and responds to
Limonene as if it were toxic. This is hard wired into the flies brain.
In humans,
Limonene's design facilitates a direct response by quickly permeating the blood-brain barrier. The result is increased systolic blood pressure. One test, reported subjective alertness and restlessness. Various
Limonene analogs can cue the brain to sexuality, buoyancy, or focused attention.
Caryophylene is a major terpene found in black pepper(15-25%), clove(10-20%) and cotton(15-25%). It is found in smaller %'s in many other herbs, and spices. It has a sweet, woody and dry clove odor and tastes pepper spicy with camphor and astringent citrus backgrounds. It contributes to black pepper's spiciness. The oil is used industrially to enhance tobacco flavor.
Caryophylene, given in high amounts, is a calcium and potassium ion channel blocker. As a result, it impedes the pressure excerted by heart muscles. As a topical it is analgesic and is one of the active constituents that makes clove oil, a preferred treatment for toothache.
It does not seam to be involved in mood change.
Pinene is the familiar odor associated with pine trees and their resins. It is the major component in turpentine and is found in many other plant essential oils in noticeable amounts including rosemary, sage, and eucalyptus. Many additional plant oils contain pinene.
Pinene is used medically as an expectorant, and topical antiseptic. It easily crosses the blood-brain barrier where it acts as a acetylcholinesterase inhibitor; that is, it inhibits activity of a chemical that destroys an information transfer molecule. This results in better memory. Largely due to the presence of pinene, rosemary and sage are both considered "memory plants."
Concoctions made from their leaves have been used for thousands of years in traditional medicine to retain and restore memory.
Pinene probably gives true skunk varieties, the ones that stink like the animal, much of their odor. It is also a bronchodilator. The smoke seems to expand in your lungs and the high comes on very quickly since a high percentage of the substance will pass into the bloodstream and brain. It also increases focus, self satisfaction and energy, which seems counterintuitive, but for the presence of
terpineol.
TERPINEOL has a lilac, citrus or apple blossom/lime odor. It is a minor constituent of many plant essential oils. It is used in perfumes and soaps for fragrance.
Terpineol is obtained commercially from processing other turpines. It reduces motillity- the capability for movement- by 45% in lab rat tests. This may account for the couchlock effects of some cannabis although that odor is not usually associated with body highs. However,
Terpineol is often found in cannabis with high pinene levels. Its odor would be masked by the pungent woodsy aromas of pinene.
BORNEOL smells much like the menthol aroma of camphor and is easily converted into it. It is found in small quantities in many essential oils. Comercially it is derived from artemisia plants such as wormwood and some species of cinnamon.
It is considered a "calming sedative" in chinese medicine. It is directed for fatigue, recovery from illness and stress.
The camphor like overtones of Silver Haze varieties are unmistakable. The high does have a calming effect as well as its psychedelic aspects. This probably means there is a large amounts of
borneol present.
DELTA 3-CARENE has a sweet pungent odor. It is a constituent of pine and cedar resin but is found in many other plants including rosemary. In aroma therapy, cypress oil, high in D-3-carene, is used to dry excess fluids, tears, running noses, excess menstrual flow and perspiration. It may contribute to the dry eye and mouth experienced by some marijuana users.
LINALOOL has a floral scent reminiscent of spring flowers such as lily of the valley, but with spicy overtones. It is refined from lavender, neroli, and other essential oils. Humans can detect its odor at rates as low as one part per million in the air.
Linalool is being tested now for treatment of several types of cancer. It is also a component of several sedating essential oils. In tests on humans who inhaled it, it caused severe sedation. In tests on lab rats it reduced there activity by almost 75%.
PULEGONE has a minty-camphor odor and flavor that is used in the candy industry. It is implicated in liver damage in very high dosages. It is found in tiny quantities in marijuana.
Pulegone is an acetylcholinesterase inhibitor. That is, it stops the action of the protein that destroys acetylcholine, which is used by the brain to store memories. It may counteract THC's activity, which leads to low acetylcholine levels. The result is you would forget more on THC alone than THC accompanied by pulegone.
1,8-CINEOLE is the main ingredient in oil of eucalyptus. It has camphor-minty odor. It is also found in other fragrant plants and in minor amounts in marijuana. It is used to increase circulation, pain relief and has other topical uses.
Cineole easily crosses the blood-brain-barrier and triggers a fast olfactory reaction. Eucalyptus oil is considered centering, balancing and stimulating. It is probably the stimulating and thought provoking part of the cannabis smoke stream.
Terpenes and their interactions with each other and resultant effect on brain activities is fascinating teritory, and another level of exploration and creativity for seed breeders. By learning the odors of the
terpenes you may be able to predict the mind altering properties each lends to a bud.
