Honey breakthrough reveals manuka's secrets
3 September 2009
New research on New Zealand's world-famous antibacterial manuka honey has unveiled another of its secrets.
Watson and Son, a major New Zealand producer of manuka honey, in collaboration with Professor Peter Molan of Waikato University's Honey Research Unit, has commissioned research by a specialist research laboratory in Singapore, which shows that a special molecule acts to augment the antibacterial activity of methylglyoxal in the honey – a process known as synergy.
The unique type of antibacterial activity in manuka honey was discovered in research at the University of Waikato in 1982. Evidence shows manuka's special antibacterial properties are effective at healing wounds, but research also shows that this activity is present in only some manuka honeys.
Last year, Waikato University Associate Professor Merilyn Manley-Harris of the Chemistry Department, showed that methylglyoxal was responsible for the antibacterial activity in manuka honey.
However Prof Molan has long maintained there is also a synergy at work in the honey and last October, New Zealand beekeeper-chemist Denis Watson commissioned a specialist research laboratory in Singapore to investigate several active fractions in manuka honey. Mr Watson is one of New Zealand's largest manuka producers. In partnership with iwi groups in the Far North he has more than 15,000 beehives in manuka plantations around New Zealand.
Dr Manley-Harris and Prof Molan say they are delighted companies are taking the initiative to commission research of this calibre.
The results have proven the existence of a formerly secret synergist: a special molecule that combines with the methylglyoxal molecule and other fractions in the honey to create the very powerful antibacterial activity the honey is world famous for. The discovery is also the key to understanding why the clinically proven antibacterial activity is so effective and why international research to date has shown that bacteria fail to develop the resistance that is inevitable with conventional antibiotics.
Research is now underway in a special project between Waikato University's Honey Research Unit and Watson and Son to confirm the mode of action of the synergist and to further understand its interaction with other fractions including methylglyoxal. This latest research will provide the medical industry with a full scientific understanding of the antibacterial properties of manuka.
This research has huge relevance to the vitally important active manuka honey industry, says Prof Molan.
"The industry is now worth in excess of $100 million in export earnings, but not all manuka honeys are equal and the way to test potency has been an issue for some time," he says.
"My original assay uses a simple test method of comparing the bacterial kill-zone of a honey sample to the kill-zone of a standard antiseptic (in this case phenol). For a variety of reasons this can't be perfect and is open to interpretation and a margin of error. The ideal objective is to have a simple analytical chemical test that can be carried out by any lab anywhere in the world. But such a test isn't possible until we know what we're trying to measure. Discovering the synergist was the key," Prof Molan says.
"Our work now includes developing an algorithm to find the strength of a honey's antibacterial activity by measuring the level of the synergist and the level of methylglyoxal present. It will then be possible to very precisely determine the non-peroxide activity of manuka honey (the 'original manuka activity') by chemical analysis."
Meanwhile, WaikatoLink, the research commercialisation division of the University of Waikato, will launch a new global consumer standard for manuka honey later this month. The standard will give consumers complete assurance as to what they’re buying and will use Prof Molan's name, says WaikatoLink Commercial Manager Fraser Smith.
"Professor Molan is acknowledged as the discoverer of active manuka honey. He was awarded the MBE for his work and is arguably the most published honey scientist in the world. Consumers know and respect him and his work. Putting his name on the standard and on the jar makes sense and gives consumers surety about what they’re getting," Mr Smith says.