Tea tree oil and silver together make more effective antiseptics

In the fight against infected skin wounds, mixing tea tree oil and silver or putting them in liposomes (small spheres made from natural lipids), greatly increases their antimicrobial activity and may minimise any side effects. Wan Li Low and colleagues from the University of Wolverhampton presented research at the Society for General Microbiology meeting in Harrogate March 30 which showed that although both tea tree oil and silver (in the form of silver nitrate) were effective against a range of micro-organisms, when low concentrations of the two agents were combined, their antimicrobial activity increased. They carried out laboratory tests on pathogens that are involved in skin infections. Bacteria such as Staphylococcus aureus (which is a common cause of skin infections and abscesses) and the yeast Candida albicans, which causes thrush, were killed. These positive findings led the researchers to use microscopic spherical bodies called liposomes, made of phospholipids, the naturally occurring lipids or fats in the cell wall's membranes, to deliver the silver and tea tree oil mix to infected wounds the pathogens. This technique allows controlled release and therefore has the potential to use lower, less toxic, concentrations of the antimicrobial agents to treat infected wounds. This may also be of value to treat antibiotic resistant strains such as MRSA. Used alone, both silver and tea tree oil can cause side effects in patients. Over exposure to silver can cause a bluish-grey discolouration of the skin and applying unregulated amounts of tea tree oil externally can cause skin irritation. With increasing life expectancy, age related conditions such as chronic leg ulcers or bedsores are likely to become more common. Current treatments using traditional silver-based creams and dressings use relatively high metal concentrations. Creams containing lower amounts of the agents could provide safer and readily available over-the-counter antiseptic compounds for effective treatment without damaging the surrounding skin.