terpinen-4-ol, α-terpinene, and α-terpineol components active
None significantly more active than the others or TTO
Two active components:
terpinen-4-ol and α-terpineol
Combination significantly more effective than either component
F = 40.17, df = 2, p < 0.0001
Active and inactive:
α-terpinene and 1,8-cineole
F = 26.24, df = 2, p < 0.0001
α-terpinene and p-cymene
F = 10.50, df = 2, p = 0.0014
Active and inactive:
α-terpineol and 1,8-cineole
F = 56.43, df = 2, p < 0.0001
α-terpineol and γ-terpinene
and F = 19.86, df = 2, p < 0.0001
The ten most abundant components of the commercial sample of TTO.
The relative percentages in the oil as observed by GC/MS.
The normal range for α-terpinene is 5-13%.
Composition of commercially purchased components that were active or part of a significant synergism
Terpinen-4-ol is not the only active component, α-terpineol and α-terpinene are just as active
Terpenes are shown to cause a loss of membrane integrity and disrupt proton motive force (Sikkema et al. 1995; Cox et al. 1998)
These components are not active on their own but contribute to the overall activity of the oil
In bacteria, 1,8-cineole has been shown to disrupt the cell membrane to allow active components in (Carson et al. 2006)
Revise ISO for TTO to contain more α-terpinene
Use of TTO in alternative treatments of infectious disease
More work with TTO and anthrax endospores in containment labs
Clinical trials for prevention/healing of cutaneous infections in places where refrigeration of antibiotics is impossible
• Carson, C. F., K. A. Hammer, and T. V. Riley. 2006. Melaleuca (Tea Tree) Oil: a review of antimicrobial and other medicinal properties. Clinical Microbiology Review 19: 50-62.
• Carson, C. F., and T. V. Riley. 1993. Antimicrobial activity of essential oil of Melaleucaalternifolia. Letters in Applied Microbiology 16: 49-55.
• Carson, C. F., and T. V. Riley. 1995. Antimicrobial activity of the major components of the essential oil of Melaleuca alternifolia. J. of Applied Bacteriology 78: 264-269.
• Cox, S. D., J. E. Gustafson, C. M. Mann, J. L. Markham, Y. C. Liew, R. P. Hartland, H. C. Bell, J. R. Warmington, and S. G. Wyllie. 1998. Tea tree oil causes K+ leakage and inhibits respiration in Escherichia coli. Letters Applied Microbiology 26: 355-358.
• Raman, A, U. Weir, and S. F. Bloomfield. 1995. Antimicrobial effects of tea tree oil and its major components on Staphylococcus aureus, Staphylococcus epidermidis, and Propionibacterium acnes.Applied Microbiology 21: 242-245.
• Sikkema, J., J. A. De Bont, and B. Poolman. 1995. Mechanisms of membrane toxicity of hydrocarbons. Microbiological Reviews 59: 201–222.