Terpenes are a diverse class of organic hydrocarbon compounds that are often used as a means of defence by plants and insects that produce them due to their strong aroma and anti-bacterial effect. They are a major component of “essential oils”. Although sometimes used interchangeably with the word “terpenes”, terpenoids (or isoprenoids) are modified terpenes as they contain additional functional groups, usually oxygen-containing.
Terpenes are made up of linked, repeating isoprene molecules, making them quite volatile compounds and easily combustible. They have a range of attractive tastes and smells including that of fresh berries, citrus, mint, pine to name just a few.
Terpenes were adapted by the cannabis plant, as with other plants that produce them, as both a deterrent to predators and as an attractor to pollinators. Terpene production can be influenced by not only the strain of hemp, but the climate, weather, age, maturation, soil type and fertilisers that the plant is exposed to during its growth.
Terpenes have diverse structures ranging from the relatively basic structure of the mono-terpene Limonene pictured below…
to Squalene, a more complex triterpene which serves as the universal precursor to natural steroids like Testosterone:
Terpenes and their effects
Cannabis contains more identified terpenes than any other plant species based on current knowledge. The cannabis plant has had over 255 different kinds of terpenes currently identified. The most abundant are:
Myrcene, for example, induces a sleepy, tired attitude, while limonene can make the consumer feel happy. Others contain imperceptible effects, such as caryophyllene’s gastro–protective properties.
Terpenes themselves are thought to produce significant biological effects of their own in mammals, many in line with the reported benefits of CBD. They also interact with CBD itself in a number of unique ways and may enhance the effects of CBD. In fact, some terpenes can bind directly to CB1 and CB2 receptors to differing degrees which is thought to explain why some terpenes can induce calm whereas others seem to provide increases to alertness, energy and focus.
Beyond just changing how a user feels, it has been shown previously that some terpenes can modulate the brain’s neurotransmitters including dopamine and serotonin by altering their rate of synthesis and the availability of their receptors; this may explain which some terpenes have powerful effects on pain and mood, two areas that dopamine and serotonin signalling regulate.