Could Bacteria From Honeybees Replace Antibiotics?

Bee bacteria release an array of antimicrobial compounds depending on the microbe they're up against. (Photo: John/Flickr).

Bacteria are increasingly outsmarting our most overused antibiotics, creating a boom of drug-resistant diseases. This could be the dawn of a "post-antibiotic era," the World Health Organization has warned, when "common infections and minor injuries which have been treatable for decades can once again kill."

Maybe it's time for plan bee?

Honey is a natural antibacterial, which helps explain why it never goes bad — and why people have used it as medicine for thousands of years. Its viscosity, acidity and sugar content make it good at sealing wounds, and it even contains small amounts of hydrogen peroxide. But there's also something else at work. Could honey's secret weapon against bacteria be other bacteria?

Researchers in Sweden recently discovered a unique group of lactic acid bacteria living inside honeybees' "honey stomachs," an enlarged section of esophagus where the insects store nectar while foraging. According to a newly published study, those 13 bacteria are experts at stifling other bacterial infections, including dangerous superbug strains such as methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and vancomycin-resistant Enterococcus (VRE).

The bee bacteria beat every pathogen they faced, a promising result given the global threat posed by superbugs. They've only been tested against human-infecting bacteria in a lab setting, but they did work wonders for 10 horses with persistent wounds. The bacteria were mixed with honey and applied directly to the horses' wounds, which had resisted other attempted remedies. The mixture healed all 10.

These bacteria represent "one of the greatest symbiotic flora ever found in a single organism," the researchers write, protecting all honeybee species — and at least some stingless bees — from the microbial threats they face while gathering nectar. Although the exact mechanisms remain a mystery, the researchers say the secret to such strong results is likely the variety of active substances involved.

"Antibiotics are mostly one active substance, effective against only a narrow spectrum of bacteria," lead author and University of Lund microbiologist Tobias Olofsson says in a press release. "When used alive, these 13 lactic acid bacteria produce the right kind of antimicrobial compounds as needed, depending on the threat. It seems to have worked well for millions of years of protecting bees' health and honey against other harmful microorganisms. However, since store-bought honey doesn't contain the living lactic acid bacteria, many of its unique properties have been lost in recent times."

Each of the 13 lactic acid bacteria (LAB) plays a role in turning nectar into honey, according to the study, although their ratios vary in naturally harvested honey depending on the nectar source, the bees' health and the presence of other microbes in the collected nectar. "We noticed early that the LAB symbionts react in a synergistic matter and defend themselves by secreting a variety of active compounds that inhibit other microbial growth," the researchers write. "These interesting numerical variations and varying production of active compounds appear to be a well-established symbiosis among bees, LAB symbionts, flowers' nectars and microbial threats that varies with season and honeybee health."

This study bodes well for developing countries, given the availability of fresh honey, but also for many developed nations where antibiotic resistance is on the rise. The researchers say their next step is to investigate wider use of these bacteria against topical infections in more animals — including humans.