Honey and its antibacterial properties

[wolski888]

Antioxidants react with reactive oxygen species (such as hydrogen peroxide) to produce water. And example of this is catalase which is present in bacteria such as E. coli and P. aeruginosa.

It is also known that Honey has antibacterial properties. One factor is hydrogen peroxide that kills the bacteria. Buckwheat honey, for example, has a great amount of antioxidants (causing its dark colour) and a great amount of hydrogen peroxide (more than most honeys). Don't they contradict each other?

And in an experiment I did, Buckwheat had the most negative effect on the growth of the previously mentioned bacteria. other honey's such as Clover, Wildflower, and Agave showed no antibacterial activity. Is there any way to make sense of this?

Another factor is water concentration. Honey is a lower amount of water tend to be more effective against bacteria. Buckwheat honey, again for example, has a low amount of water which agrees with the fact that it is good against bacteria.

Also, I researched that a protein that bees have called defensin-1 is found in honey. And it has the most effect on antibacterial activity. So does that mean, from the experiment, that Buckwheat usually contains a lot of defensin-1 while the honeys do not. Explaning how they showed no inhibition of growth in bacteria.

Any comments or if possible primary articles would be appreciated.

 

[zoobyshoe]

And in an experiment I did, Buckwheat had the most negative effect on the growth of the previously mentioned bacteria. other honey's such as Clover, Wildflower, and Agave showed no antibacterial activity. Is there any way to make sense of this?

I know nothing about biology, but I became curious about reports honey was anti-bacterial, and did some googling last year. Most sites said the honey had to be raw and unprocessed, pretty much straight from the hive. Clover was said not to give the bees the right raw materials to produce the antibacterial stuffs. Wildflower was supposed to be good. It's interesting to find your experiment contradicted that latter claim.

I was curious to what extent primitive man might have used honey to combat infections, but didn't find anything particularly enlightening about that.

 

[JorgeLobo]

Honey by its chemical composition is not that "antibacterial" - most of the stuff about its "antioxidants" is hype. That said, it does have significant physical antibacterial activity and that's attrbutable not so much to water content (%) as water activity. Water activity refers to the amount of free water avaiable for microbial growth and honey's high sugar content binds water well. This factor is more static (inhibits growth) than cidal (killing). Honey has been used to treat infections and it's efficacy is attributed to lowering of water activity.
Be aware that honey is also been associated with fatal botulism in infants due to bacterial carriage.

 

[mbrmark]

Dear Wolski888 Try this website.
http://bio.waikato.ac.nz/honey/contents.shtml
has loads of information on honey
can also use google using keywords "honey" and "pdf" to find article listed in the primary literature on honey

 

[Ryan_m_b]

You may want to try a pubmed search.

 

[wolski888]

Thank you all. I have tried Google Scholar, found some good stuff and should be fine.

 

[256bits]

Honey by its chemical composition is not that "antibacterial" - most of the stuff about its "antioxidants" is hype. That said, it does have significant physical antibacterial activity and that's attrbutable not so much to water content (%) as water activity. Water activity refers to the amount of free water avaiable for microbial growth and honey's high sugar content binds water well. This factor is more static (inhibits growth) than cidal (killing). Honey has been used to treat infections and it's efficacy is attributed to lowering of water activity.
Be aware that honey is also been associated with fatal botulism in infants due to bacterial carriage.

Since the OP has answered, I hope this is not considered a hijack:
Question for you since you seem to know the field.
Packing meat in salt, or brine, inhibits spoilage due to the dying out of cells, bacterial cells are rendered inert.

Does packing in sugar also dry out bacterial cells - any osmotic pressure involved - or is it only a function of what you have mentioned regarding water activity.