Effectiveness of Salvadora persica extracts against common oral pathogens.

OBJECTIVE: The purpose of this study was to evaluate the antibacterial activity of ethanol and hexane extracts of Salvadora persica against common oral pathogens.

MATERIALS AND METHODS: Well diffusion, Minimum Inhibition Concentration (MIC), Minimum Bactericidal Concentration (MBC), and Broth microdilution tests were used to determine the optimum antimicrobial concentrations of S. persica extracts against Streptococcus mutans ( S. mutans ), Streptococcus sanguis ( S. sanguis ), and Streptococcus salivarius ( S. salivarius ) over 1, 3, 6, 12, and 24 h. Chlorhexidine (CHX) 0.2% was used as a positive control.

RESULTS: The findings showed that the microbial activity of both extracts was concentration-dependent. Ethanol extract of S. persica at 25, 50, and 100 mg/ml had more growth inhibitory effect against all isolates compared to hexane extract. In addition, ethanol extract at 8 mg/ml (MBC value) was able to eradicate the growth of all isolates. S. sanguis and S. salivarius were very sensitive to hexane extract and required 4 mg/ml (MBC value) for their eradication while S. mutans was the most resistant (MBC = 8 mg/ml).The statistical findings of CFU counts showed no significant difference ( p  = 1.000) in antibacterial effectiveness between the two extracts against all isolates. A significant decline overtime in CFU counts was noted, except at 12 h and 24 h where no significant difference ( p  = 0.793) was observed and was comparable to CHX.

CONCLUSION: Ethanol and hexane extracts of S. persica were found to exhibit maximum antimicrobial activity against S. mutans , S. sanguis and S. salivarius at high concentrations.