Terpene profile: limonene

Terpenes are responsible for giving cannabis its unique array of aromas. Ever wonder what gives Lemon Skunk its powerful citrus aroma? Well, it's limonene, a tiny terpene produced in the resin glands of those pretty buds you're smoking.

However, recent research shows that these tiny compounds do much more than just give off nice smells. They may also play a big role in influencing the effects (both recreational and medicinal) of cannabis in general.

WHAT IS LIMONENE?

Limonene is a terpene found in many plants. In cannabis, it is produced by the trichomes of the flowers. It is a very fragrant terpene that gives off strong citrus aromas. Apart from cannabis, you’ll find limonene in citrus peels and plants like lemongrass, mint, rosemary, pine, and many others.

Limonene has many different uses. In the food industry, for example, limonene is often used as an additive to enhance the flavor of certain foods. It is also used in cosmetic products to add a fresh, citrus aroma to creams, lotions, balms, etc.

Limonene is also a natural insecticide, so it is often added to insecticidal sprays as an alternative to harsher chemicals. In fact, limonene is also biodegradable and rapidly breaks down into carbon dioxide and water.

Limonene has also been shown to cut through grease and grime, which is why you’ll find it as an active ingredient in commercial cleaning products. Orange Power or Mr Muscle’s Orange range, for example, contain limonene. It can also be used as a paint stripper, and is often used in the manufacturing of glues and paints. It is a flammable compound that has also been considered for its potential as a biofuel.

WHAT ARE THE EFFECTS AND POSSIBLE MEDICAL BENEFITS OF LIMONENE?

Despite its recognizable aroma, limonene also has interesting ways of acting upon the body. The medicinal benefits of limonene may not be surprising, seeing as the compound has long been used in both traditional and modern medicine.

As an essential oil, limonene can be used in aromatherapy to offer relief from stress and anxiety, as well as provide calming effects. Limonene is also believed to have anti-fungal and antibacterial properties. Additionally, it is often used in cosmetics because it can help promote the absorption of other compounds through the skin.

THE SCIENCE BEHIND LIMONENE

Recent studies suggest that limonene may also be beneficial for contributing to the treatment of certain cancers. For example, a 2009 study published in the Journal of Carcinogenesis showed that limonene improved the effectiveness of docetaxel on human prostate cancer cells.[1] The authors of the study suggest this could be because the compounds combine to affect proteins involved in apoptosis (natural cell death).

Research from the Cancer Research Institute at Tata Memorial Centre, Mumbai, suggests that orange oil (which contains between 90–95% limonene) helped reduce the growth of liver tumors in rats.[2]

Essential oils containing limonene have also been shown to effectively reduce stress and anxiety while producing sedative effects. A 2014 study showed that both limonene and its metabolite (perillyl alcohol) helped reduce stress in rats purposely put under environmental stress.[3]

Other studies have argued that limonene can help reduce pain. An animal study published in the journal Nutritional Neuroscience in 2015 showed that limonene reduced heightened pain sensations in rats.[4]

Further research states that limonene’s anti-inflammatory functions can help relieve heartburn, boost metabolism and weight loss, dissolve gallstones, and improve the healing of wounds.

THE SIGNIFICANCE OF TERPENES

These findings are obviously very significant and have created a heightened interest in limonene, among many other terpenes. Research like the above has also helped open up the discussion of medical marijuana beyond the cannabinoids THC and CBD.

The benefits of limonene make a strong case for preserving the terpenes in cannabis. Unfortunately, many terpenes are lost when cannabis is cured or combusted. Luckily, the world of concentrates is helping bring about extraction methods that retain as many terpenes as possible.

LIMONENE-RICH CANNABIS STRAINS

Among all the different terpenes found in cannabis, limonene and myrcene are usually found in the highest concentrations. As you may imagine, strains with strong citrus aromas will usually contain higher amounts of limonene than strains with woody or earthy scents.

If you’re interested in strains with higher concentrations of limonene, consider trying the following:

• Super Lemon Haze: As the name suggests, this strain has a powerful citrus aroma thanks to limonene. It’s an uplifting sativa from the Haze family that has long been super-popular head stash.
• Durban Poison: Unlike Super Lemon Haze, Durban doesn’t have a very citrusy aroma. Instead, it tends to be more earthy and sweet. Nonetheless, Durban Poison usually contains high concentrations of limonene.
• Jack Herer: This is a legendary strain that contains high amounts of limonene, as well as the terpenes pinene and myrcene.