Study Confirms Antiviral Effect of Whole Essential Oils
A study just released in the Journal of Phytotherapy research affirms the antiviral action of essential oils of Eucalyptus, Tea Tree and Thyme. The study brings up two important points:
- Essential oils are effective in destroying the Herpes Simplex Virus. The effects of essential oils such Melissa, Tea Tree, Geranium and Hyssop have a significant body of research describing the effect against this particular virus.
The Herpes Virus is far and away the most studied, likely as so many folks are in need of treatment. At the same time, it would be very interesting to see more studies on essential oils for treatment of Influenza types. There's no reason the same effects wouldn't be found -- it would be helpful to have scientific backing as to which oils work best for which viruses. (Though Aroma-Medicine doctors have a pretty good idea -- you will find descriptions of antiviral activity for many essential oils on the web).
- The final line of the abstract indicates the power of the natural synergy of essential oils. It is noted that the whole Tea Tree oil is ten times more effective than any of the single isolated compounds, with lower toxicity. Proponents of natural medicine have always held this to be the case of pure essential oils, and other plant-based medicines.
Astani A, Reichling J, Schnitzler P. Department of Virology, Hygiene Institute, University of Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
Essential oils are complex natural mixtures, their main constituents, e.g. terpenes and phenylpropanoids, being responsible for their biological properties. Essential oils from eucalyptus, tea tree and thyme and their major monoterpene compounds alpha-terpinene, gamma-terpinene, alpha-pinene, p-cymene, terpinen-4-ol, alpha-terpineol, thymol, citral and 1,8-cineole were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1) in vitro.
These essential oils were able to reduce viral infectivity by >96%, the monoterpenes inhibited HSV by about >80%. The mode of antiviral action has been determined, only moderate antiviral effects were revealed by essential oils and monoterpenes when these drugs were added to host cells prior to infection or after entry of HSV into cells. However, both essential oils and monoterpenes exhibited high anti-HSV-1 activity by direct inactivation of free virus particles.
All tested drugs interacted in a dose-dependent manner with herpesvirus particles thereby inactivating viral infection. Among the analysed compounds, monoterpene hydrocarbons were slightly superior to monoterpene alcohols in their antiviral activity, alpha-pinene and alpha-terpineol revealed the highest selectivity index. However, mixtures of different monoterpenes present in natural tea tree essential oil revealed a ten-fold higher selectivity index and a lower toxicity than its isolated single monoterpenes.