It uses hydrogen peroxide, acidity, osmotic effect, high sugar concentration and polyphenols to actively kill bacterial cells, said a study presented at the 247th National Meeting of the American Chemical Society (ACS).
Previous studies have shown that honey inhibits the formation of biofilms by disrupting quorum sensing, which weakens bacterial virulence, rendering the bacteria more susceptible to conventional antibiotics, said the researchers.
Honey to control biolfilms?
Susan Meschwitz, assistant professor, department of chemistry and Salve Regina University, told FoodQualityNews.com that it would make sense to prevent and control biofilm formation by using naturally occurring compounds such as honey.
She said they are testing various honeys to see if they can inhibit quorum sensing and initial studies indicate that some can.
“We are in the preliminary stages of our research where we are looking at the effect that honey has on a process called quorum sensing, which is a bacterial communication system.
“It is believed that in many bacteria, this quorum sensing controls the production of virulence factors and biofilm formation.”
Antibiotic resistance is becoming a growing issue in the food industry with a US study showing that Kosher chicken has the highest frequency of antibiotic-resistant E. coli at nearly twice that of conventional products.
The US Centers for Disease Control and Prevention (CDC) said last year that antibiotic use for promoting growth of food producing animals plays a role in drug resistance and should be “phased out”.
Researchers will test the same honeys for their ability to inhibit biofilm formation.
“We are in the process of developing these assays. Many of these effects have already been seen with New Zealand Manuka honey.
“We are hoping to see this effect also with honeys from floral sources common to North America. Also, the fact that honey uses various mechanisms for its antimicrobial properties makes it less likely for bacteria to be able to build up a resistance.”
The osmotic effect, which is the result of the high sugar concentration in honey, draws water from the bacterial cells, dehydrating and killing them, Meschwitz said at the ACS meeting.
"The unique property of honey lies in its ability to fight infection on multiple levels, making it more difficult for bacteria to develop resistance," she said.