Terpenes. You should get familiar with that word if you haven't already. These are aromatic compounds which give plants their unique scent and serve as natural pesticides. And yes, cannabis is one of those plants. With all the recent changes in the legal status of weed, scientists are now diving into a subject that was previously very difficult to study. The result? Plenty of new discoveries which are reshaping how science, and the public, view this particular plant.
Photo source: UnSplash.com
With that, let us meet our newest scrutinized compound: phellandrene. Phellandrene is what is known as a "secondary terpene". It is actually made up of two distinct isomeric molecules, alpha-phellandrene and beta-phellandrene. These are present in lower concentrations than primary terpenes in the cannabis plant and have received less attention. But don't let that fool you. Even though phellandrene is present in low concentrations in the cannabis plant it has been shown to have potential health benefits.
Phellandrene has been found to be present in higher concentrations in strains of cannabis that help decrease anxiety. It may also have anti-inflammatory properties. One study found that alpha-phellandrene inhibited leukocyte adhesion to the walls of blood vessels, as well as significantly inhibited the production of the pro-inflammatory cytokines. It may also have anti-cancer benefits, with data from in-vitro studies showing that alpha-phellandrene can induce necrosis in human liver tumors.
Another interesting fact about phellandrene is its potential for practical implications. It is a very useful natural pesticide. A 2017 toxicity study tested the genetic toxicity of the beta-phellandrene and found that, at high doses (2850, 1425, 712.5mg/kg beta-phellandrene) can damage DNA and may even damage chromosomes to cause mutations. Please note that these concentrations are way above the concentration of phellandrene present in cannabis, with concentrations of beta-phellandrene averaging around 2 mg/g and alpha-phellandrene at below 1 mg/g.
Another industry which relies on phellandrene is the cosmetics industry. It is used for its pleasant scent (peppery, minty, and slightly citrusy). The source of this phellandrene comes from oil extracted from the eucalyptus plant. The eucalyptus plant is actually a good source of phellandrene. In fact, the terpene was named after this plant (Eucalyptus phellandra, aka Eucalyptus radiata) and is a source for phellandrene oil, which is then used in cosmetics and fragrances.
A picture of eucalyptus leaves. Photo source: UnSplash.com
The percentage of alpha- and beta-phellandrene differs by strain. Another 2017 biochemistry study found that the strains "Trainwreck" and "Jack Herer" contained trace amounts of alpha-phellandrene. A follow-up to that study identified the strains "Ace of Spades" and "SAGE" as containing trace amounts of alpha- and beta-phellandrene. This is relevant for the medical marijuana industry. The idea is to use strains with higher concentrations of phellandrene to treat various diseases, such as cancer and anxiety.
Sources: International Journal of Plant Sciences, PubChem.org, Leafly.com, Life Sciences, Nutrition and Cancer, Environmental Toxicity and Pharmacology, ProfofPot.com, hytiva.com, Organic Letters, Wikipedia, Cannabis and Cannabinoid Research