Eucalyptol is a cyclic monoterpene with an ether bridge (R−O−R’) between carbon 1 and 8, and for this “structural” reason this compound is also known as 1,8-cineole. It is the main component in the oil extracted from the leaves of Eucalyptus species, where it represents the majority (90% or more) of all the aromatic compounds. This terpene also represents one of the main active components of several other essential oils from various plant species (e.g. Camphor laurel, Croton, Psidium, Rosmarinus, Salvia, Sweet basil, Tea tree and Wormwood). It represents a minor constituent of Cannabis Sativa L.
Eucalyptol’s function within the cannabis plant and impact on its direct environment
Eucalyptol has recently been identified as a volatile rhizosphere component in Arabidopsis, and in species such as Salvia and Artemisia it is known to behave as “natural killer” for the surrounding life (phenomenon called “allelopathy”) thus suppressing the germination, growth and reproduction of herbaceous plants having no resistance to such substance. (essentially clearing the surrounding area of the root system of competing flora)
Eucalyptol’s flavour and aroma profile
Eucalyptol emanates a balsamic, sweet-minty smell with bitter, camphor-like undertones and a typical pungent, cooling, almost spicy taste. It is insoluble in water, but miscible with ether, ethanol, and chloroform. It has been identified as “GRAS” (Generally Recognized As Safe) by the Flavor Extract Manufacturers Association (FEMA). Also, it is approved by the US Food and Drug Administration (FDA) as a flavouring agent for food use.
The medicinal properties of Eucalyptol
Eucalyptol exhibits a range of medical properties: it is antimicrobial, anti-inflammatory, antioxidant, analgesic, antibiotic, antifungal, antiviral against herpes simplex virus and spasmolytic and its use was tested in a variety of pathologies. Its effects include:
- Improvement of brain function and increasing cerebral blood flow: Studies have shown that the inhalation of Eucalyptol increases cerebral blood flow and enhances the activity of a brain area called “cortical”. The administration of Eucalyptol has also shown to determine improvements in the cerebral blood flow; significant improvements in cerebral blood flow are observed even after inhaling cannabis smoke.
- Anti-inflammatory and antioxidant against inflammatory airway diseases: Eucalyptol has shown to have a positive effect on various airway diseases including; colds, rhinitis, respiratory infections, and sinusitis. Eucalyptol effects on the respiratory tract may be summarized as follows:
- Protective action against necrosis of the liver. Gastric damage induced by alcohol (ethanol) consumption or colon damage in various animal models.
- Gastro-protective effect on ulcer: by increasing the secretion of gastric mucus.
- Analgesic: According to studies in humans, inhalation of eucalyptus oil has demonstrated to have a relieving effect on pain and to reduce blood pressure in patients who underwent total knee replacement. Eucalyptol is also associated in relieving a specific type of pain called “orofacial pain” located on the mouth and face area, by acting as an antagonist of the TRPV1 channel, involved in the release of substances resulting in the generation of impulses sent to higher CNS areas where they will often be perceived as pain.
- Anti-anxiety: If inhaled this aromatic terpene has also shown to reduce anxiety in patients before starting a procedure called “selective nerve root block” (SNRB), utilized in pain management.
- Antibacterial and antifungal: Eucalyptol demonstrated antibacterial activity against Bacillus subtilis and antifungal properties against Trichophyton mentagrophytes, Cryptococcus neoformans, and Candida albicans.
- Preventive effectin rats against the sexual transmission of Herpes simplex virus type 2, a condition often associated with HIV.
- Potential preventive role against tuberculosis.