Comparing the Effects of Alfalfa Root Extract and Chlorhexidine on Streptococcus mutans, Primary Contributor to Tooth Decay
Abstract
Tooth decay is one of the most prevalent infectious diseases and mouthwashes play a crucial role in combating it. Given the adverse effects of chemical mouthwashes and the growing popularity of herbal alternatives, this study aims to investigate the impact of alfalfa root extract on Streptococcus mutans, the primary bacteria responsible for tooth decay. The study’s findings were compared with those of chlorhexidine, a standard chemical mouthwash. Alfalfa roots were processed and extracted using the maceration technique. The extract's effect on S. mutans proliferation was assessed through Disk Diffusion and Well Diffusion assays, with chlorhexidine as a standard for comparison. The study also determined the alfalfa extract’s Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). Alfalfa extract showed dose-dependent antimicrobial activity, with inhibition zones at ≥62.5 mg/mL in disk diffusion and ≥31.25 mg/mL in well diffusion. Inhibition zones increased significantly from 24 to 48 hours at higher concentrations (p < 0.05). At ≥250 mg/mL, alfalfa produced larger zones than chlorhexidine (p < 0.05), with comparable effects at 125 mg/mL. The MIC was 31.2 mg/mL and MBC was 62.5 mg/mL indicating bacteriostatic and bactericidal effects. Alfalfa root extract shows significant antimicrobial activity against S. mutans, comparable to chlorhexidine at higher concentrations. It is a promising foundation for creating an effective, low-cost mouthwash to combat dental caries with minimal side effects. Further clinical studies are needed to fully understand the extract's impact on tooth decay.
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Details
Primary Language
English
Subjects
Bacteriology
Journal Section
Research Article
Authors
Publication Date
February 8, 2026
Submission Date
August 9, 2025
Acceptance Date
January 7, 2026
Published in Issue
Year 2026 Volume: 10 Number: 1
