Antibacterial Properties of Citrus limon and Pineapple Extracts on Oral Pathogenic Bacteria (Streptococcus mutans and Streptococcus sanguis)

Background: Micro-organisms resistant to most of the commercial antibiotics are rapidly expanding and there is an urgent need for detection of novel antimicrobial compounds. Tooth decay is a dental infection with bacterial sources such as Streptococcus mutans and Streptococcus sanguis. Objectives: The present study aimed to evaluate the in vitro antibacterial effects of different concentrations of Citrus limon peel, pineapple fruit, and pineapple peel extracts on oral pathogens such as S. mutants and S. sanguis. Materials and Methods: In this experimental study, the hydroethanolic extracts of the selected plants were prepared by maceration method and their antibacterial effects were evaluated by agar well diffusion method. Results: Two-fold dilutions of plant extract solutions were tested to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against each selected microorganism. The results of the current study revealed that pineapple peel extracts had the highest antibacterial effect on S. sanguis (MIC: 1.56 mg/mL and MBC: 3.12 mg/mL). Pineapple fruit had the lowest antibacterial activity against S. mutans (MIC: 25 mg/mL and MBC: 100 mg/mL). C. limon peel had significant antibacterial activity against S. mutans and S. sanguis. Conclusion: The peel of C. limon and pineapple had significant antibacterial activity against cariogenic microorganisms such as S. mutans and S. sanguinis.