Australia’s stingless bees may help fight antibiotic resistance

For generations, Australia’s tiny native stingless honey bees have been part of Indigenous medicine. Scientists now believe they may hold clues to tackling one of modern medicine’s biggest challenges: antibiotic-resistant bacteria. Researchers at the University of Sydney examined the potential medicinal benefits of honey and propolis (a mixture of plant resin and beeswax that bees use to build their nests) produced by Australia’s stingless bees, and the early results are hard to ignore. They found that the honey stopped the growth of every bacterium tested, including two hard-to-treat pathogens. These sugarbag bees hold valuable clues to tackling the growing threat of antimicrobial resistance. The findings are published in the journal PLOS One.

Australia’s stingless bees could combat antibiotic resistanceStingless bees, also known as sugarbag bees, are native to Australia. Their honey has long been used in Indigenous medicine. However, almost all research on medicinal honey has focused on the European honey bee. These Australian species have been largely left out of the conversation. A new study led by PhD candidate Jasmin Li aimed to close that gap. Li’s team tested honey and propolis from Tetragonula carbonaria, a native Australian stingless bee, against 16 bacterial and fungal pathogens. The new study builds on earlier research from the same university. Both studies add to what scientists know about these bees, which have been overlooked for far too long.

What Li and the team found was striking. The honey stopped the growth of every bacterium they tested. That list included two hospital pathogens, Pseudomonas aeruginosa and Klebsiella pneumoniae, both of which are difficult to treat.

The sugarbag honey was comparable in strength to medical-grade Manuka and Jarrah honeys. That matters because those honeys are already well studied, giving the native honey a benchmark against which to be measured. That’s not all.

The researchers found that the honey also worked against fungi. It was active against the fungi that cause ringworm and athlete’s foot, two common infections that affect millions of people.

One of modern science’s biggest challenges is tackling growing antimicrobial resistance. This happens when pathogens change in ways that allow them to survive the medicines designed to kill them. When that happens, drugs that once worked stop working, leaving doctors with fewer treatment options. This is where honey from Australia's native stingless bees has caught scientists’ attention. Some of the pathogens in this study are already a concern for researchers tracking resistance, and the honey’s effect on them is a reason to keep investigating.

However, the same cannot be said of propolis. The researchers found that it was highly potent yet very selective. This means it worked well against some pathogens but not others. That pattern differs sharply from the propolis produced by European honey bees.

Selectivity can be a strength. A product that targets specific germs may be easier to study and may leave other useful microbes alone. The research does not yet establish how far that potential could extend, but the contrast is enough to make the propolis worth a closer look."Now that we've shown how powerful sugarbag honey is, the next step is finding out what makes it so effective, because those compounds could offer new ways to tackle difficult infections," co-author Dr Kenya Fernandes from the university's Faculty of Science, who supervised the research, said in a statement.

Neither product’s antimicrobial activity could be explained by the usual known compounds. That points to antimicrobial substances that have yet to be identified, which could become valuable leads for new drugs as resistance grows.