Purpose The purpose of our study is to investigate how to prevent dental caries by limiting the virulence of S. mutans such as their ability to proliferate and adhere to the tooth surface with the compounds of Diospyros kaki (D. kaki) peel, Momordica charantia (M. charantia) and Canavalia gladiata (C. gladiata) extracts.
Methods To determine the anti-microbial effect and Minimum Inhibitory Concentration (MIC) of the extracts, broth microdilution and agar spreading test. Potential antimicrobial activity of D. kaki peel. M. charatia and C. gladiata extracts against S. mutans was evaluated by disc diffusion method. For identification of adhesive ability with different concentrations of extracts on S. mutans, culture plates were stained with 1 ㎖ of 0.01% crystal violet for 15 minutes at room temperature and then eluted with 1 ㎖ of EtOH:Acetone (8:2) solution for 15 minutes in 37 °C incubator. Eluted solutions were then evaluated by spectrophotometer at 575nm.
Results and discussion Experiments were conducted to investigate the effectiveness of D. kaki peel, M. charantia and C. gladiata extracts on limiting the proliferation of S. mutans. MIC was measured to verify antibacterial activities of D. kaki, M. charantia and C. gladiata extracts had a bacteriostatic effect on S. mutans. At 0.25% and higher conc. of M. charatia extract was effective for growth inhibition on S. mutans. However, no significant evidence for bactericidal effects was found by paper disk assay. From the adhesion ability assay, M. charatia extract had an anti-adhesive effect.
Conclusions These results indicate that M. charatia extract had antibacterial activity and anti-adhesive effect on S. mutans. M. charatia extract as their antibacterial and anti-adhesive ability may be used to prevent or treat dental caries.