A Sydney researcher has unlocked the mystery of the miraculous healing powers of honey, adding to the calls for its use as a first line defence against serious infection.
Research undertaken by Dr Shona Blair, at Sydney University's School of Molecular and Microbial Biosciences, has shed some light on the unusual antibacterial activity of certain types of honey, leading to a greater understanding of the ability of some honeys to kill pathogenic bacteria and promote wound healing.
In a study, the potent Leptospermum honey, commonly found in Australia and New Zealand and made from jelly bush flowers found in isolated parts of northern New South Wales and from a related plant known as Manuka from New Zealand, was effective against many different drug resistant clinical isolates, including the notorious Golden Staff bacteria.
Selected Leptospermum honey attacked bacteria via several different mechanisms.
A test organism, E. coli, was stressed with honey and the genes it used to cope with the attack were identified using microarrays. Microarrays are a relatively new tool in molecular biology that allows us to study the behaviour of thousands of genes at once. After E. coli was treated with Leptospermum honey it reacted in a unique way. Some of the genes E. coli turned on were the same as those it uses to deal with stresses such as exposure to acid, salt, or heat. However, the entire gene expression pattern after exposure to
Leptospermum honey was unique when compared to any other known response. As honey "attacks" bacteria from several different angles they are overwhelmed and unable to develop resistance. This is extremely important as antibiotic resistance is one of the biggest problems faced by modern medicine, with little relief in sight.
There has been evidence for the medical use of honey throughout the history of the human race. Almost every culture that had access to honey has utilised it as a therapeutic agent, with its use as a wound dressing being particularly popular and persistent across many different cultures. It is likely that the prevalence in the use of honey as a wound dressing stems from its antibacterial activity, usually due to the production of hydrogen peroxide. However, the Leptospermum honey used in these studies has considerable antimicrobial activity of unknown origin.
Honey not only possesses significant antibacterial activity, it has also been shown to actively promote healing, regardless of the infection status of the wound. This study found that honey, but not sugar, directly stimulates human cells that are important in the immune response and in wound healing. Although further investigations are needed this stimulation begins to explain some of honeys therapeutic benefits.
Commenting on her findings, Dr Blair said that: 'Despite the ancient and modern evidence suggesting an enormous potential for honey as a wound dressing, it is largely ignored. The broad aim of the study was to investigate the therapeutic potential of honey using various in vitro techniques. This work was undertaken to generate a greater understanding of the range and mode of action of honey and help to increase its acceptance and use as an economical and effective wound dressing.'