Scientists develop biodegradable gum

By Eric Chima

University scientists have managed to make gum that will not stick to shoes, create biodegradable plastics and even regrow skin tissues – all with the help of corn.

Graciela Padua, associate professor in food science and human nutrition, spent the past six years working with a protein called corn zein, a byproduct of ethanol. She used it to create a variety of products, including a biodegradable, non-sticky gum that could eventually replace the synthetic gums that are chewed today.

“(Marketing) corn-based gum is not far-fetched,” Padua said. “Companies are interested, and if they take the lead and we supply the technology, there’s no reason we couldn’t see it.”

The gum hardens, instead of becoming sticky, once it is spit out. Once it lands on the ground, it breaks down to nothing in as few as two weeks, Padua said.

Gum companies have been working on biodegradable gums for a long time, according to Soo-Yeun Lee, assistant professor of nutrition sciences. In February, Wrigley patented a gum made of a blend of proteins that are found in the seeds of various grains.

Lee, a sensory scientist, was in charge of testing the University’s corn zein gum for texture and taste.

Lee said some compounds successfully matched synthetic gums in texture, while others did better in matching flavor. She was confident, though, that a compound could be created to match normal gums in both texture and flavor.

Padua said the same formula used to make the corn-based gum could be adapted to make biodegradable plastics and different kinds of films for packaging. Her latest project involves using the versatile zein as a building block for human tissues to grow on.

“In order to grow tissues to heal wounds or organs you need the cells, and they need a physical support to guide their growth,” Padua said. “Normally the body provides the infrastructure, but when you have a wound, it can’t do that. The zein can.”

Zein has several advantages over other polymers that have been used to grow tissues in the past, Padua said. It is biocompatible, meaning that it would integrate with the rest of the body’s tissues, and it is capable of bonding with the cells to provide a better support.

Padua has begun working on the tissue regeneration project with University researchers in electrical engineering and biochemistry. Padua said it would be at least three years before the group has results to pass on to the medical community, and at least five years before the process could be put into use.

The problem with zein-based products, at least for now, is its relatively high cost. Because it is treated mainly as a byproduct, it is not readily available. The cost of making a zein-based chewing gum, for instance, would be significantly higher than synthetic gums, Lee said.

“It would definitely be an advantage for the environment and consumers if it’s the right price,” Lee said. “But the extra cost will be passed down to consumers, so will consumers pay more money?”

But Tom Schuh, operations manager of the city of Champaign, said the type of gum being chewed is less important than the chewer.

“The main problem gum causes for us is aesthetically,” Schuh said. “It looks terrible. (Biodegradable gum) would be helpful, but it would still look bad for the two weeks it was sitting there … What we need is for scientists to develop a human that won’t litter.”