Antimicrobial Effect of Psoralea corylifolia Extract on Streptococcus mutans, Streptococcus sobrinus, Candida albicans

Background: The increasing prevalence of dental caries and oral candidiasis has led to growing interest in natural antimicrobial agents with fewer adverse effects than conventional antiseptics.Psoralea corylifolia, a traditional medicinal plant, has been reported to possess antimicrobial properties; however, its effects on major oral pathogens remain unclear.Methods: The antimicrobial activity of P. corylifolia ethanol extract against Streptococcus mutans, Streptococcus sobrinus, and Candida albicans was evaluated using the paper disk diffusion method, optical density (optical density at 600 nm) measurements at 6, 12, 24, 48, and 72 hours, and colony-forming unit (CFU) assays.Data were analyzed using one-way analysis of variance followed by Tukey's post-hoc test, with p0.05 considered statistically significant.Results: The extract demonstrated significant concentration-dependent antimicrobial activity against all tested microorganisms (p0.05).At 4 mg/ml, the maximum inhibition zones were 7.50.5 mm for S. mutans, 2.00.0 mm for S. sobrinus and 2.00.5 mm for C. albicans.Optical density and CFU analyses further confirmed significant reductions in microbial growth compared to that in the control group, with up to 9496% reduction in viable cell counts at 0.5 mg/ml.Conclusion: P. corylifolia extract exhibits measurable antimicrobial effects against major oral pathogens in vitro.Although its inhibition zones were smaller than those of chlorhexidine (13.30.6 mm for S. mutans), the extract demonstrated consistent antimicrobial activity across all experimental methods.These findings suggest that the extract has the potential to be used as a complementary natural antimicrobial agent for preventive oral care.Further studies are required to evaluate its cytotoxicity, mechanism of action, and clinical applicability.