Antibacterial Activity of Lemongrass and Kaffir Lime Leaf Extracts Against Streptococcus mutans
Keywords:
Lemongrass, Kaffir lime leaf, Antibacterial activity, Streptococcus mutansAbstract
Dental caries is a major global public health problem that affects quality of life, particularly among children, adolescents, and the elderly, impacting cognitive development, nutrition, and personality. Streptococcus mutans is recognized as the primary bacterium responsible for dental caries. This experimental study aimed to investigate the inhibitory effects of aqueous extracts of lemongrass and kaffir lime leaves against S. mutans. The antibacterial activity was evaluated using the disc diffusion method and the broth dilution method. The mechanism of acid production inhibition was assessed using the glycolytic pH drop assay. The results demonstrated that all extracts were able to inhibit the growth of S. mutans strain ATCC 25175T. The MIC found to be most effective was 1.56 mg/mL. Furthermore, the glycolytic pH drop assay revealed that the combined lemongrass and kaffir lime leaf extract at a concentration of 1.56 mg/mL achieved the greatest inhibition of pH reduction, with a rate of only 0.009 units per minute. This finding indicates a strong ability to suppress acid production by S. mutans. The study highlights the potential of these herbal extracts for development into anti-caries products, with further clinical and commercial applications in the future.
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