Wednesday, January 30, 2008

Molan: MGO Level Not Good Indicator of Honey’s Antibacterial Activity

The representation of the antibacterial activity of manuka honey as the level in it of the active component MGO would be very misleading for consumers. A paper ("Isolation by HPLC and characterisation of the bioactive fraction of New Zealand manuka (Leptospermum scoparium) honey”) recently published in the journal ‘Carbohydrate Research’ by members of the Chemistry Department at the University of Waikato shows clearly that the level of MGO does not give a good indication of the antibacterial activity of the honey. Although it is the component responsible for the activity, complex interactions with other components of the honey cause the actual antibacterial activity that results from it in the honey to vary.

The graph shown in the published paper of MGO plotted against antibacterial activity shows that for example, a level of 50 for MGO corresponds to an antibacterial activity of UMF5, but a ten times higher level of MGO, 500, corresponds to only a five times higher antibacterial activity (UMF25, not UMF50 as may be expected). The graph also shows a lot of scatter of the data, meaning that even for a single stated level of MGO the actual antibacterial activity can very quite a lot.

The currently used rating system, UMF, measures the actual antibacterial activity of each batch of honey, tested against Staphylococcus aureus, the species of bacteria that is the most common cause of wound infections. It is a very good way of showing the antibacterial activity, has been in world-wide use for many years, and has been relied on for many research papers that have been published on the antibacterial activity of honey, and relied on for a very large amount of clinical treatment with manuka honey.

Because the level of MGO is an unreliable indication of the level of antibacterial activity and can be very misleading, I can see no advantage for it to be used to indicate antibacterial activity other than if someone wanted to fool the consumer into thinking that the higher levels of MGO are giving them a level of antibacterial activity that is far higher than they are really getting.

Dr. Peter Molan
Professor in Biological Sciences & Director of the Honey Research Unit
University of Waikato
Private Bag 3105
Hamilton 3240
New Zealand

Telephone +64 7 838 4325
Fax +64 7 838 4324

Visit the Honey Research Unit on http://honey.bio.waikato.ac.nz/

2 comments:

Manuka said...

It is interesting to see what is going on there is obviously some chemical compound in there but I don't think extracting this into a drug is going to help anyone.
The bacteria won't take long to resist against it there is obviously some synergistc activity going on in the Manuka Honey .
Is there still an U(unidentified) MF?

Manuka Honey Benefit said...

"I can see no advantage for it to be used to indicate antibacterial activity other than if someone wanted to fool the consumer into thinking that the higher levels of MGO are giving them a level of antibacterial activity that is far higher than they are really getting."

I think Dr. Molan makes a good point as the average consumer will look at the numbers and naturally think that MGO 100 is better (because it is a larger number) than UMF 10+ so they will choose that particular brand.