Essential oils capable of killing superbugs, research finds


FOR MANY PEOPLE essential oils are associated with sweet-smelling rooms or a relaxing bath, but their antibacterial components make them “highly efficient” in the treatment of so-called hospital “superbugs”, according to new research.

Scientists based at Sligo Institute of Technology have discovered that some essential oils are capable of killing the most resistant bacteria including MRSA as well as Vancomycin-resistant Enterococcus (VRE) and Extended Spectrum Beta Lactamase (ESBL).

Superbugs, which have been attributed to overcrowding and poor hygiene in hospitals, are potentially life threatening, especially for people already frail due to illness.

Describing the findings as “very promising”, the research team, which includes staff from the Department of Microbiology at Sligo General Hospital, said the oils were effective against bacteria which were resistant to conventional antibiotics.

PhD student Julien Thibault said most antibiotics were “useless” in the fight against superbugs because of their enzyme content. Those antibiotics which do have an effect are so toxic that they are administered as a last resort because of risks to, for example, liver and kidney, he explained.

While essential oils are widely available in a range of outlets including pharmacies, health stores and supermarkets and are popular for use as antiseptic treatments and in aromatic oil burners, there has been little focus until now on their impact on resistant bacteria.

Essential oils are composed of plant extracts which generally contain a large number of chemicals, some of which have antibacterial properties.

The researchers tested a large range of oils and their components, and found that among the most effective at killing the MRSA, VRE and ESBL strains were clove, lemongrass, citronella, thyme, oregano, cinnamon while the popular tea tree oil was also found the be “quite effective”.

“The list is not exhaustive – a large majority of the oils tested showed activity at relatively low concentrations,” said Mr Thibault.

He said that while the results were promising, further work was needed to provide viable alternatives to patients. “This is a starting point,” he said, adding that caution was always needed when using essential oils.

Dr Fiona McArdle from Sligo IT, the supervisor on the project, said they were hoping to do further research so that the “huge potential” in the use of natural products in the treatment and eradication of superbugs could be exploited.

Mr Thibault said it had already been established that essential oils as vapour did have some antibacterial properties.