Nov. 16, 2007 -- Magnolia bark extract contains chemicals that kill bacteria that cause bad breath (halitosis), a new study shows.
Those compounds are called magnolol and honokiol, according to the study, published in the Journal of Agricultural and Food Chemistry.
In lab tests, magnolia bark extract killed virtually all of the oral bacteria it encountered.
Those bacteria included two types of bacteria that cause bad breath and a third type that causes cavities.
Nine healthy adults took a breath test an hour after eating lunch.
First, they provided a saliva sample. Then they were given breath mints or chewing gum, some of which contained magnolia bark extract. Lastly, they provided saliva samples 30 minutes and an hour after using the gum or breath mints.
Those who had gotten the products containing magnolia bark extract had a bigger reduction in their bad-breath bacteria.
For instance, those who got the mints laced with magnolia bark extract had a 61% drop in their bad-breath bacteria within 30 minutes of using the mints.
In comparison, bad-breath bacteria dropped by about 4% in that time frame for people who got ordinary mints without magnolia bark extract.
The researchers work at the Wrigley Company, which makes products including gums, breath mints, and breath strips.
They didn't scrape bark off magnolia trees. Instead, they used magnolia bark extract, magnolol, and honokiol supplied by companies in Japan and China. The study doesn't recommend a do-it-yourself brew to fight bad breath.