Soy could be a natural antimicrobial: study

Soy isoflavones and peptides may inhibit the growth of microbial pathogens that cause foodborne illnesses, according to research from Canada.

Soybean derivatives are already a common ingredient in food products such as cooking oils, cheeses, ice-cream, margarine, food spreads, canned foods and baked goods. The use of soy isoflavones and peptides to reduce microbial contamination could replace synthetic additives to protect foods, according to engineering professor Suresh Neethirajan, director of the BioNano Laboratory at the University of Guelph in Ontario.

Neethirajan and fellow researchers used microfluidics and high-throughput screening to run millions of tests in a short period. They found that soy can be a more effective antimicrobial agent than commonly used synthetic chemicals, successfully limiting the growth of bacteria including Listeria and Pseudomonas pathogens.

“Heavy use of chemical antimicrobial agents has caused some strains of bacteria to become very resistant to them, rendering them ineffective for the most part,” said Neethirajan.

“Soy peptides and isoflavones are biodegradable, environmentally friendly and non-toxic. The demand for new ways to combat microbes is huge, and our study suggests soy-based isoflavones and peptides could be part of the solution.

“The really exciting thing about this study is that it shows promise in overcoming the issue of current antibiotics killing bacteria indiscriminately, whether they are pathogenic or beneficial. You need beneficial bacteria in your intestines to be able to properly process food,” he said.

The study will be published in the journal Biochemistry and Biophysics Reports.