Effect of oleanolic acid-cyclodextrin inclusion compounds on dental caries by in vitro experiment and rat-caries model.

Earlier work in vitro showed that oleanolic acid (OA) was a potential inhibitor of insoluble glucan (ISG) synthesis from mutans streptococci (MS). In this study, two oleanolic acid-cyclodextrin inclusion compounds (OA-CDs), oleanolic acid-G1-beta-cyclodextrin (OA-G1-beta CD) and oleanolic acid-beta-cyclodextrin (OA-beta CD), were assayed for their effects on ISG synthesis from Streptococcus mutans MT8148R, and on the growth of oral bacteria. OA-beta CD inhibited ISG synthesis by 55.3 and 37.4% at 62.5 and 15.6 micrograms/ml of OA, respectively. Both OA-CDs inhibited the growth of MS, S. sanguis, and S. salivarius at 4 to 8 micrograms/ml of OA. The anticariogenic effect of the OA-beta CD was examined in a rat-caries model. Rats in the infected control groups showed the highest caries score. The infected treatment group B (0.5% OA in diet) showed lower scores than the control group. These results suggest that OA-beta CD is a potential anti-caries agent.