Microbiologists in Penn State’s College of Agricultural Sciences have received a $605,000 grant from the U.S. Department of Agriculture to study how microbial biofilms protect Listeria monocytogenes, the bacterium that causes the deadly foodborne illness listeriosis.
Jasna Kovac, Lester Earl and Veronica Casida Career Development Professor of Food Safety, along with Luke LaBorde, professor of food science, will use the funding from USDA’s National Institute of Food and Agriculture to conduct research on the interactions between microorganisms found in fruit-packing environments and Listeria monocytogenes.
“We will study the ability of environmental microorganisms to form robust biofilms together with L. monocytogenes and how these biofilms may protect L. monocytogenes from the antimicrobial activity of sanitizers,” said Kovac, assistant professor of food science. “The data generated in this project will help improve the cleaning and sanitizing used in the fresh produce industry to better control L. monocytogenes and support the production of safe food.”
Listeria and other microorganisms found in the natural environment, such as soil, can be introduced unintentionally into food-processing facilities with raw foods such as fruit. The research is needed, Kovac explained, because once introduced into the food-processing environment, Listeria and many other environmental microorganisms can grow on surfaces into microbial layers called biofilms.
“Microorganisms enclosed in a biofilm produce slimy substances that protect them from the antimicrobial activity of sanitizing chemicals by slowing down their penetration into the core of a biofilm,” Kovac said. “Biofilm formation can therefore result in reduced efficacy of antimicrobial sanitizers used to inactivate Listeria. This project will investigate the interactions between microorganisms found in fruit-packing environments and L. monocytogenes.”