CANADA – Researchers at McMaster University have developed a way to coax bacteriophages—harmless viruses that eat bacteria—into linking together and forming microscopic beads, creating a formidable defense against bacterial contamination and infection.
These beads can be used to safely get rid of dangerous infections like E. coli 0157 on food and other items.
Millions of phages are packed inside each bead, which has a diameter of roughly 20 microns (one 50th of a millimeter).
The McMaster engineering team behind the invention, led by professors Zeinab Hosseinidoust, who holds the Canada Research Chair in Bacteriophage Bioengineering, and Tohid Didar, who holds the Canada Research Chair in Nano-Biomaterials, and graduate student Lei Tian, have created a spray using nothing but the microbeads.
In a paper that was featured in the prestigious journal Nature Communications, the researchers reveal their sprayable new super-disinfectant which they claim is both food-safe and incredibly effective.
Tian collaborated with graduate student and Vanier scholar Shadman Khan to test the antimicrobial spray on food products.
“When we spray it on food, we basically gather billions of mini-soldiers to protect our food from bacterial contamination,” says Tian, who led the study as part of his Ph.D. research.
The research builds on the same chemistry work that Hosseinidoust’s lab had previously used to trigger phages to connect in quantities sufficient to form a gel.
“They link together like microscopic Lego pieces. This organized natural structure makes them much more durable and easier to package, store, and use,” she says.
Phages ousting antibiotics
Phage disinfectants and cures had shown great promise before penicillin was developed in the 1940s, but once penicillin-based antibiotics hit the market, interest in exploring their potential waned.
The effectiveness of current antibiotics is increasingly being diminished by antimicrobial resistance, sparking a surge of interest in phage research.
“When we spray it on food, we basically gather billions of mini-soldiers to protect our food from bacterial contamination.”
Phages, which are naturally present in the body and the environment, multiply when they come into contact with the target bacteria, greatly enhancing their antibacterial activity.
“It’s a chain reaction, creating a dynamic and ongoing response that is even more overpowering than antibiotics. No other antibacterial product—not even bleach—has the special properties that phages do,” Didar says.
Another significant benefit of utilizing phages in agriculture and food production is their ability to be directed very precisely to eradicate dangerous bacterial strains without eliminating beneficial bacteria that improve food flavor, aroma, and texture.
The U.S. Food and Drug Administration (FDA) has already given phages the go-ahead for use in food, so the researchers believe the novel phage spray has bright prospects for commercial use.
The research paper shows the sprayable material can eliminate E. coli 0157 in lettuce and meat, which are often the sources of disease outbreaks.
According to the researchers, the technique can easily be replicated against other bacteria that cause food poisoning like Salmonella and Listeria, either separately or in combination.
To prevent contamination at the source, the researchers claim that phage sprays might be utilized in food processing, packaging, cleaning, and even as a treatment for irrigation water and equipment.
The study finished under the auspices of McMaster’s Global Nexus for Pandemics and Biological Threats, expands and combines earlier work from Didar’s group with that of Hosseinidoust’s lab to develop microscopic sensors and surfaces to detect and ward against food infections.
The study also has Leon He, Kyle Jackson, Ahmed Saif, and Zeqi Wan as co-authors.