Hebrew U researcher targets dangerous food ‘slime’

Hard to see but dangerous, it lurks on those fresh vegetables you bought for health reasons. It’s a layer of bacteria called “biofilm,” and an Israeli researcher has found a way to stop it from contaminating your food.

Biofilm is better known as “slime,” which sounds gruesome and accurately reflects its threat. Slime makes millions of people sick every year.

A researcher who’s an American immigrant to Israel has a cure. His process has been patented and is in the pre-market development stage.

Michael Brandwein, a graduate student at Hebrew University of Jerusalem, developed a way to disrupt the bacteria and prevent the formation of biofilm.

Using a molecule synthesized at Hebrew University, Brandwein was able to interfere with the genetic processes that lead to biofilm formation. Besides preventing bacterial biofilm on fruits and vegetables, said Brandwein, the technology could ensure that shipped frozen and fresh foods of all kinds will be safer when they get to the consumer.

The thin, barely visible coat of slime that grows on many household surfaces, such as countertops, sinks, fruits, and vegetables consists of germs that researchers believe are at the root of many persistent and chronic bacterial infections.

As people around the world seek out healthier diets, demand for fresh fruits and vegetables has grown. To satisfy the demand, food wholesalers are shipping more produce from further distances. Shipping containers provide a fertile host for the formation of the bacteria that form biofilms. The bacteria thrive in the moist, closed environment of the packages, and they eventually begin to emit a slimy, glue-like substance that sticks to whatever surface they attach themselves to. That goo makes bacteria far more dangerous than “dry” germs, scientists say. The slime is more difficult to remove, and it includes a higher than usual concentration of bacteria.

In the case of produce shipments, the surface of the fruits and vegetables themselves gets covered in biofilm. Unless cleaned thoroughly, that produce could become the very opposite of healthy. According to the United States Centers for Disease Control and Prevention, food-borne diseases cause about 48 million illnesses each year in the US, 45 percent of which are attributable to bacteria.

Scientists have discovered that biofilms form when bacteria “communicate” with each other through a process called “quorum sensing.” When molecules in bacteria detect germs in sufficient quantity, they trigger a genetic process that leads to the formation of biofilm. In his research, Brandwein discovered that a molecule called TZD, synthesized at Hebrew University, has the ability to interfere with this genetic process. Added to packaging and shipping crates, TZD prevents the formation of biofilm, resulting in cleaner, healthier produce.

For his efforts, Brandwein, a researcher under the supervision of Prof. Doron Steinberg from the Biofilm Research Laboratory of the Hebrew University’s Dental Faculty, was chosen as one of two graduate students to receive a Kaye Innovation Award during the 77th annual meeting of the Hebrew University Board of Governors on June 11. He is set to receive his master’s degree in biomedical sciences at the Hebrew University this year.

Brandwein developed the solution for corrugated cardboard boxes, the worldwide medium for transporting most fresh agricultural produce. The technology was successfully incorporated into industry-specific acrylic polymers meant to coat the corrugated cardboard used for fresh produce. Hebrew University, through its technology transfer company, Yissum, holds patents on the process and has signed an agreement with B.G. Tech of Kibbutz Beit Guvrin for further development and commercialization.

“While millions of dollars have been spent globally to develop antimicrobial polymers, no one has succeeded in developing and marketing anti-quorum sensing/anti-biofilm polymers. We therefore predict that our product will enjoy exclusivity for many years to come,” said Brandwein. “We envision our technology being applied to frozen food packaging, poultry and meat packaging and other areas within the food packaging industry.”