Humble plant oils found to kill superbugs

Published on Tuesday 30 March 2010 23:09

ESSENTIAL oils could be a cheap and effective alternative to antibiotics and potentially used to combat drug-resistant hospital superbugs, according to new research.

Extracts of common kitchen herbs and spices have been found to be especially effective at eliminating potentially lethal infections.

The study, which is due to be presented at the Society for General Microbiology's spring meeting in Edinburgh this week, shows that extracts of thyme and cinnamon were found to be particularly efficient antibacterial agents against a range of staphylococcus bugs.

Though strains of the "staph" bug are commonly found living harmlessly on human skin, they can cause infection in individuals whose immune systems are depressed.

Invasive staph infections are less common than skin infections, but they are much more serious. This is because once the bacteria penetrate the skin and enter the blood, or the organs, they can rapidly multiply and release toxins which can be fatal.

However, long-term use of antibiotics have rendered some strains drug-resistant, such as Staphylococcus aureus (MRSA), which makes them extremely difficult to treat.

The research was led by Professor Yiannis Samaras and Dr Effimia Eriotou, from the Technological Educational Institute of Ionian Islands, in Greece, who tested the "antimicrobial activity" of eight plant essential oils.

They found that thyme essential oil was the most effective and was able to almost completely eliminate bacteria within 60 minutes.

"Not only are essential oils a cheap and effective treatment option for antibiotic-resistant strains, but decreased use of antibiotics will help minimise the risk of new strains of antibiotic resistant micro-organisms emerging," said Prof Samaras.

The Greek team believes essential oils could have diverse medical and industrial applications which can be used both external or internally.

"The oils – or their active ingredients – could be easily incorporated into antimicrobial creams or gels for external application.

"In the food industry, the impregnation of food packaging with essential oils has been successfully trialled. They could also be included in foodstuffs to replace synthetic chemicals that act as preservatives," they said.

Essential oils have been recognised for hundreds of years for their therapeutic properties, although very little is still known about how they exert their antimicrobial effects in humans.

The researchers insist various scientific studies have demonstrated essential oils are not only well tolerated, but are effective against a range of bacterial and fungal species, and that their therapeutic value has been shown for the treatment of a variety of conditions, including acne, dandruff, head lice and oral infections.

Aberdeen-based microbiologist Professor Hugh Pennington said that while he supported such research, he was cautious about its effectiveness.

"This sort of idea has been around for a long time. I don't think they do any harm, but how much good they do, well, I'm slightly sceptical.

"But it's worth a try. The crucial thing is to get evidence that these oils work in patients, really.

"The problem is that when this bug causes problems in patients, it's deep inside the body and I don't think these oils are going to be much good for that."

However, Prof Pennington added that since the staph bug spent most of its life on people's skin, a mild way of reducing the number of bugs which did not require recourse to antibiotics would be "a good thing".

He said recently that purpose-built isolation facilities and extra staff to run them were needed to combat superbugs in Scotland.

Ancient methods recognise natural cure

VARIOUS essential oils have been used medicinally at different periods in history.

Cinnamon oil can be used for infection of the respiratory tract, arthritis and general pains. It calms the feeling of exhaustion and depression, tones the whole body and stimulates the glandular system, thus easing period pains.

Thyme oil strengthens the nerves, aids memory and concentration, can help with the feeling of exhaustion and combats depression, while it fortifies the lungs and helps with colds, coughs, asthma and laryngitis.

Lavender oil has a soothing and calming effect on the nerves, relieving tension, depression and panic. It is effective for headaches, migraines and insomnia.

Frankincense oil is a skin tonic and is effective with sores, wounds, scars and skin inflammation. Some studies have also shown it to be useful against skin cancer and the effects of ageing.

Black pepper oil can be used for pain relief, flu, colds, and to increase circulation.