Gum with bark to take bite out of bad breath

CHICAGO (Reuters) - Magnolia bark extract -- a traditional Chinese medicine -- may be the newest weapon in the war on bad breath.

Chewing gum maker Wm Wrigley Jr Co said on Tuesday that it has added a bit of this germ-killing compound to their Eclipse gum and mints. The hope is to not simply mask bad breath, as most strongly flavored mints and gums do, but to kill odor-causing bacteria.

Magnolia bark extract has long been a staple of traditional Chinese medicine. It is used to treat fever, headache and stress -- and has proven effective against germs that cause ulcers. Recent studies have shown it has low toxicity and few side effects.

Most bad breath occurs when bacteria in the mouth break down proteins, producing foul-smelling sulfur compounds. But many antimicrobial agents cause nasty side effects like tooth staining, making them impractical for oral care.

According to research published last fall by company scientists, researchers in Wrigley's lab tested magnolia bark extract on cultures of three types of oral microorganisms. The extract killed 99.9 percent of the microorganisms within five minutes, the researchers said.

In a study of nine volunteers who chewed the mints after lunch, they killed off more than 61 percent of the germs that cause bad breath within 30 minutes -- which is comparable to some commercial mouthwashes, the company study found. Mints without the extract were only 3.6 percent effective.

Gum with the extract took a bit longer to kill oral bacteria. The extract also helped kill a group of bacteria that causes tooth decay.

Wrigley's tree-bark gum will be on U.S. store shelves later this summer. Mints with the tree-bark extract will be available this fall.

(Editing by Will Dunham and Philip Barbara)