WEST LAFAYETTE, Ind., Dec. 7 (UPI) -- U.S. researchers say a nanoparticle can hold and release an antimicrobial agent, extending the shelf life of foods susceptible to Listeria contamination.
Scientists at Purdue University say they've developed several forms of a nanoparticle that could contain and stabilize nisin, a food-based antimicrobial peptide, keeping it effective for up to three weeks against Listeria monocytogenes, a university release said Tuesday.
The potentially lethal food-borne pathogen found in meats, dairy and vegetables is especially troublesome for pregnant women, infants, older people and others with weakened immune systems.
"People have been using nisin for a number of years, but the problem has been that it is depleted quickly in a food system," said Arun Bhunia, a Purdue professor of food science. "This nanoparticle is an improved way to deliver the antimicrobial properties of nisin for extended use."
A solution containing the nanoparticles and free nisin could be sprayed onto foods or included in packaging, Yuan Yao, who developed the nanoparticle/nisin pairing, said.
The solution would have an equal amount of both free nisin and nisin on the nanoparticles.
"When you reduce the amount of free nisin, it will trigger a release of more nisin from the nanoparticles to re-establish the equilibrium," Yao said. "There will be a substantial amount of nisin preserved to counteract the Listeria."
Yao said a sufficient amount of nisin to combat Listeria could be preserved for up to 21 days.
