AN INVESTIGATION OF DITERPENES FROM THE LEAVES OF RABDOSIA-TRICHOCARPA AND THEIR ANTIBACTERIAL ACTIVITY AGAINST ORAL MICROORGANISMS

The ethanolic extract of Rabdosia trichocarpa leaves showed antibacter ial activity against cariogenic mutans streptococci and periodontopath ic Porphyromonas gingivalis. Chromatographic separation and purificati on of the extract afforded ten diterpenes, including one novel ent-kau ren type compound named trichoranin. Some of these compounds possess p otent antibacterial activity against these oral micro-organisms, indic ating that these diterpenes may be useful natural substances for the m aintenance of oral health.