Honeybee hives may hold a secret to fighting cavities, researchers say. Michel Hyun Koo and his colleagues at the University of Rochester and the State University of Campinas in Brazil have determined that propolisthe sticky material bees concoct to hold their hives togethercontains potent anticavity ingredients.

Propolis, the composition of which can vary greatly depending on the location of a honeybee hive, contains more than 100 compounds. The most promising anticavity propolis so far comes from hives in southern Brazil, which Koo found after studying more than 2,500 Brazilian bee samples. The active ingredients in propolis, the scientists say, inhibit the action of glucosyltransferase (GTF) enzymes, key players in the buildup of plaque on teeth, as well as enzymes produced by the plaque-building bacteria Streptococcus mutans.

The hive-derived substances blocked nearly 95 percent of enzyme action in laboratory tests and between 60 to 70 percent on surfaces mimicking the exterior of teeth. In addition, the propolis cut the cavity rate in rats by approximately 60 percent, the scientists report. "The potential with these natural products is enormous," Koo says. "The bees are doing a great work for human health by facilitating the identification of compounds with applicability to dental science."