Essential Oil Research Updates
These are abstracts of research studies recently published in peer-reviewed journals around the world, along with our summary and opinions.
This first study investigates anticancer potential of the essential oil of the 'Mosquito Plant' or 'Feverleaf Teabush', Ocimum viride. This oil is primarly composed of Thymol (found, of course, in significant quantities in Thyme essential oil), along with a number of sesquiterpinoids and other constituents. It is important to note when reviewing ANY research such as this, and particularly with anti-cancer research, that these are only preliminary studies. They do not deeply investigate the possibilty for development of a protocol for humans -- though they do pave the way for more research to be peformed in this medical realm using essential oils.
This study notes that the essential oil from Ocimum viride induces cell death in a particular line of colon cancer cells - inducing cancer cell death is a crucial component of any cancer treatment, as one of the features of any cancer is that the cells do not naturally die-off, but continue to replicate without natural limitations.
Study: Cytotoxic and apoptotic activity of essential oil from Ocimum viride towards COLO 205 Cells. Food Chem Toxicol. 2009 Oct 20.
Sharma M, Agrawal SK, Sharma PR, Chadha BS, Khosla MK, Saxena AK. Oncology Group, Pharmacology Division, Indian Institute of Integrative Medicine,
Jammu, J & K, India-180016.
"We investigated the apoptosis inducing effect of essential oil (EO) from aerial parts of Ocimum viride in human colorectal adenocarcinoma cells (COLO 205 cell line). The COLO 205 cells were exposed to 0.0125 - 0.1 mul/ml of EO for 24, 48 and 72 h. Growth inhibition was determined by sulphorhodamine B (SRB) assay. Double staining with Acridine orange and Ethidium bromide for nuclear changes was performed. Cell cycle analysis and change in mitochondrial membrane potential was quantified by flow cytometry. Subsequently, using annexin V/PI assay, the proportion of cells actively undergoing apoptosis was determined. Changes in DNA were observed by DNA ladder assay. Eventually the surface morphology of apoptotic cells was studied by scanning electron microscopy."
"EO (essential oil) is cytotoxic to COLO 205 cells in dose and time dependent manner, as is evident by SRB assay. This observed cell death was due to apoptosis, as established by annexin V/PI assay, DNA Ladder formation and scanning electron microscopy. Our results reveal that EO has apoptosis inducing effect against COLO 205 cells in vitro and is a promising candidate for further anticancer study."
This second study investigated the in-vitro (in the test tube) effects of Tea Tree essential oil against the 'Swine Flu' virus. The study only looks at the direct eradication of the virus, and not at the way essential oils interact with the immune system (essential oils have been shown to improve immune system function in a number of ways). The study DOES conclude that Tea Tree essential oil can have a direct eradication effect on the H1N1 virus.
Study: In vitro antiviral activity of Melaleuca alternifolia essential oil. Lett Appl Microbiol. 2009 Sep 18.
Garozzo A, Timpanaro R, Bisignano B, Furneri PM, Bisignano G, Castro A. Department of Microbiological and Gynaecological Sciences, University of Catania, Catania, Italy.
Abstract Aims: To investigate the in vitro antiviral activity of Melaleuca alternifolia essential oil (TTO, or Tea Tree essential oil) and its main components, terpinen-4-ol, alpha-terpinene, gamma-terpinene, p-cymene, terpinolene and alpha-terpineol. Methods and Results: The antiviral activity of tested compounds was evaluated against polio type 1, ECHO 9, Coxsackie B1, adeno type 2, herpes simplex (HSV) type 1 and 2 viruses by 50% plaque reduction assay. The anti-influenza virus assay was based on the inhibition of the virus-induced cytopathogenicity. Results obtained from our screening demonstrated that the TTO and some of its components (the terpinen-4-ol, the terpinolene, the alpha-terpineol) have an inhibitory effect on influenza A/PR/8 virus subtype H1N1 replication at doses below the cytotoxic dose. The ID(50) value of the TTO was found to be 0.0006% (v/v) and was much lower than its CD(50) (0.025% v/v). All the compounds were ineffective against polio 1, adeno 2, ECHO 9, Coxsackie B1, HSV-1 and HSV-2. None of the tested compounds showed virucidal activity. Only a slight virucidal effect was observed for TTO (0.125% v/v) against HSV-1 and HSV-2. (Ed. note: Tea Tree and MANY other essential oils HAVE been shown effective in treating HSV in humans. This is not a result of direct eradication of the virus, but an interaction of the essential oil with our cell physiology that prevents infection and speeds healing of outbreaks). Conclusions: These data show that TTO has an antiviral activity against influenza A/PR/8 virus subtype H1N1 and that antiviral activity has been principally attributed to terpinen-4-ol, the main active component. Significance and Impact of the Study: TTO should be a promising drug in the treatment of influenza virus infection.