Limonene Everything
you need to know

Everything you need to know about Limonene 

Limonene is the third most abundant terpene in Cannabis
and the second most prevalent terpene on Earth
(Hartsel, Eades, Hickory, & Makriyannis, 2016). 
As we learn more about Cannabis, we realize that this ancestral plant's therapeutic
effects do not come only from cannabinoids like THC or CBD. Terpenes and flavonoids
also have a crucial role in determining the outcomes and benefits of a patient's treatment.   

Terpenes are essential oils found on the flower’s trichomes and define
several factors such as flavor, smell, and euphoric effects. When combined with other
chemical compounds such as cannabinoids, they can enhance
medicinal benefits, known as the entourage effect. 
Currently, there are more than a hundred and fifty terpenes identified
in cannabis plants; their potential is being sought after by many
and can ultimately define the effects produced and desired.
Terpenes exist in many plants to defend the plants
from harmful environmental factors, such as predators. 
Aside from its characteristic aroma, Limonene can absorb quickly
into the bloodstream and can improve other terpenes’ absorption.  

What is Limonene? 

Limonene, commonly known as d-limonene for its chemical structure,
is a terpene present in lemons and citrus apart from Cannabis. 
It is present as a monoterpene in resin glands, used for centuries as
a natural treatment for multiple health issues and an ingredient
in household items. It can be found concentrated in orange peels,
other fruit rinds, cosmetics, and cleaning products. 
Like other terpenes, Limonene is produced by a wide range of plants other than Cannabis,
including juniper, citrus fruits, lemons, rosemary, and peppermint.
Its aroma can be identified as zesty citrus and can reduce allergic lung
inflammation apart from its antioxidant properties (Hansen, Wolkoff & Larsen 2016).
It is also known for its anti-anxiety attributes, potent antifungal and antibacterial qualities,
and stimulating the immune system. Currently, it is also considered
to help in the potential suppression of breast cancer cells.
While they are abundant in strains that smell like lemon,
this is not always the case. To determine if a strain is high in Limonene,
you'll need to lab-test to know its actual content.
Limonene happens in trace amounts, frequently less than 2%. 

Limonene aroma? 

Limonene fragrance is identified as citrusy, bitter, sweet, and sour.
As stated, it is found in fruits like lemon and oranges and works as a protection mechanism.
Its smell helps against pests that perceive the aromas as being toxic (Kushka, 2019). 
The Entourage Effect: How Limonene interacts with other Cannabinoids 
As explained by Doctor Ethan Russo in his 2011 study, cannabinoids
and terpenes blend in the human body to modify one another effects and,
in essence, create an overall different, or "greater," efficacy based on the same molecules
present and, of equal importance, the ratios in which they appear (Russo, 2011). 

Limonene interacts with cannabinoids like CBC-A, THC-A, CBD-A, CBC AND CBG,
and functions with other terpenes such as linalool and caryophyllene.
One of Limonene's recognized properties is reducing
THC's anxiety and creating a feeling of well-being. 

Limonene Benefits 

Limonene has shown promising potential in the following treatments:  

Antioxidant and Anti-inflammatory: 

A 2015 study in the Food and Chemical Toxicology found that
Limonene exhibits antioxidant effects. At varying doses, it was a non-toxic method
of reducing oxidation-induced DNA damage
(Bancali, 2015) 

A 2017 study published demonstrated Limonene's ability to
reduce disease activity and organ damage. These effects resulted from the
terpene's antioxidant and anti-inflammatory properties,
which have been reported by other researchers
(Yu, Yan, Zun, 2017). 

Anti-anxiety:  

Limonene is widely used to treat anxiety and insomnia.
A 2013 study published studied Limonene's ability to reduce depression and
anxiety in rodent models of these disorders. The results suggested Limonene
improved anxiety-like states by interacting with the brain's serotonin system
(Costa, Cury, 2013). 

Anticancer: 

A study published in the New Zealand journal found that Limonene
inhibited the cells' growth while suppressing transplanted tumors' proliferation.
Another study in 2009 determined that it could be used to treat individual
prostate cancer types. A 2012 study published demonstrated that as part
of a blood orange oil emulsion, Limonene could kill human colon cancer cells
(Kotamballi, 2012). 

Antidepressant: 

limonene has shown effective in raising the mood. Some suggest the terpene
as a natural antidepressant that assists restore homeostasis
by blocking stress-induced immunosuppression. 

Antifungal: 

 Limonene inhibits the growth of fungi, distinctly of species that attack food. 

Immune Stimulation: 

Limonene has been successful in regulating and boosting immune function.
This terpene shows multiple therapeutic benefits, including mood enhancement,
digestion improvements, and anti-inflammatory properties.
These give Limonene exceptional value for hundreds of illnesses
and conditions related to inflammation, such as cancer,
asthma, and arthritis. Other related benefits are:
aid with acid flux (heartburn), dissolve gallstones,
and a mild appetite suppressant 
(Harris, 2010).  

**Note: As always, with medical conditions and symptoms,
please consult with your doctor for personalized medical advice.
The Food and Drug Administration has not
evaluated the statements made regarding these products.
The efficacy of these products has not been confirmed by FDA-approved research.
These products are not intended to diagnose, treat, cure, or prevent any disease. 

References:

Hartsel, J., Eades, J., Hickory, B., & Makriyannis, A.
(2016, February 19).
Cannabis sativa and Hemp. Retrieved October 15, 2020,
from https://www.sciencedirect.com/science/article/pii/B978012802147700053X 

Hansen JS, Nørgaard AW, Koponen IK, Sørli JB, Paidi MD, Hansen SW,
Clausen PA, Nielsen GD, Wolkoff P, Larsen ST.
Limonene and its ozone-initiated reaction products
attenuate allergic lung inflammation in mice. J Immunotoxicol.
2016;13:793–803. doi:10.1080/1547691X.2016.1195462.
 [PubMed]   [CrossRef]   [Google Scholar] 

Kushka. (, 2019).
What is Limonene?
from https://www.dinafem.org/en/blog/what-is-limonene/ 

Staff, L. (2020, July 28).
What Is Limonene & What Are Its Benefits in Cannabis?
Retrieved October 15, 2020, from
https://www.leafly.com/news/cannabis-101/what-is-limonene-and-
what-are-the-benefits-of-this-cannabis-terpe 

N; B. (n.d.). The antioxidant and antigenotoxic properties
of citrus phenolics Limonene and naringin. Retrieved October 15, 2020,
from https://pubmed.ncbi.nlm.nih.gov/25896273/ 

Z; Y. (n.d.). D-limonene exhibits anti-inflammatory and antioxidant properties
in an ulcerative colitis rat model via regulation of iNOS, COX-2, PGE2, and ERK signaling pathways.
Retrieved October 15, 2020, from https://pubmed.ncbi.nlm.nih.gov/28260017/ 

Costa, C., Cury, T., Cassettari, B., Takahira, R., Flório, J., & Costa, M.
(2013, February 23).
Citrus aurantium L. essential oil exhibits anxiolytic-like activity
mediated by 5-HT(1A)-receptors and reduces cholesterol
after repeated oral treatment.
Retrieved October 15, 2020, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3598547/ 

BS; C. (n.d.). D-limonene rich volatile oil from blood oranges
inhibits angiogenesis, metastasis, and cell death in
human colon cancer cells. Retrieved October 15, 2020,
from https://pubmed.ncbi.nlm.nih.gov/22935404/ 

Harris, B (2010).
Phytotherapeutic uses of essential oils. In: Baser KHC, Buchbauer G (eds).
Handbook of Essential Oils: Science, Technology, and Applications.
CRC Press: Boca Raton, FL, pp. 315–352.