Researchers from the University of Sydney in Australia have found that bees that collect nectar from a variety of local plants make antibacterial honey that is more potent than single-source honey, which is made from only one plant or flower.
During a 5-year study, the results of which were published in the journal Microbiology Open, researchers analyzed 56 honey samples from more than 35 bee colonies, including areas affected by the 2020 bushfires in New South Wales and Victoria.
The researchers found that more than 75 percent of honey samples made from local plants were able to kill dangerous bacteria, even when diluted.
Researchers examine a hive at Tocal Bee Research Centre. Credit: Kenya Fernandes
Wildlife researcher Kenya Fernandez (University of Sydney)
Multifloral honey
It was noteworthy that multifloral honey showed much higher efficacy against bacteria such as coliform bacteria (E. coli) and Staphylococcus aureus.
The most prominent sources of nectar in multifloral honey are eucalyptus plants, tea trees, and Melaleuca trees, also known as "leaf bark trees," as each plant leaves its own chemical signature in the honey, explains Kenya Fernandez, a researcher in mycology at the University of Sydney.
She adds in a statement published on the university's website that "when bees collect nectar from several different plants, the compounds combine and produce a rich, antibacterial honey."
Single-source honey, however, was less effective because of the lower chemical diversity. This means that multifloral honey contains more bioactive compounds, such as hydrogen peroxide, phenols, and antioxidants, all of which help kill bacteria, even when the honey is diluted to only 10%.
Researchers examine a hive at Tocal Bee Research Centre. Credit: Kenya Fernandes
More than 75 percent of honey samples made from local plants were able to kill dangerous bacteria (University of Sydney)
Local and global health benefits
The importance of these findings lies in the fact that they offer natural solutions to the problem of bacterial resistance to antibiotics.
The World Health Organization has declared this problem to be one of the top 10 global health threats, and Australian studies indicate that it is clearly emerging there, with some bacteria's resistance to antibiotics increasing by more than 25% in 2024.
Kenya says: "Natural honey provides a natural mechanism that makes it difficult for bacteria to resist it, because it works through several chemical compounds at once, and not on a single target as with traditional antibiotics."
To reap these benefits, Dr. Kenya emphasizes the importance of continuing to support local beekeepers, through preserving biodiversity and rehabilitating forests after fires.
