Compounds isolated from licorice root may help prevent cavities, according to researchers at the University of California, Los Angeles. In test tube studies, the scientists showed that an extract from a plant root that is used to make licorice candy and other products contains at least two compounds that appear to be potent inhibitors of Streptococcus mutans, a major cause of dental caries. Their study is scheduled to appear in the Feb. 24 print version of the Journal of Natural Products, a monthly peer-reviewed joint publication of the American Chemical Society and the American Society of Pharmacognosy.