Abstract
Periodontal diseases and tooth decay are the most common oral and dental diseases in the world. Oxidation, habits, diet and bacterial infections are among the effective factors in the mentioned diseases. Streptococcus mutans is the main bacteria that causes tooth decay. New strategies needed in order to prevent these diseases. Bacterial exopolysaccharides (EPSs) could be considered for this purpose. In this study, minimum inhibitory concentration (MIC) and minimum batericidal concentration (MBC) tests were used to determine the antibacterial properties of EPS against S. mutans. Then, using the crystal violet method, the postbiotic effect on the reduction of biofilm formation (adhesion) by S. mutans bacteria was investigated. In addition, the antioxidant properties of these compounds were measured using the DPPH method. The results showed that exopolysaccharide has a significant inhibitory effect against the S. mutans growth. The minimum inhibitory concentration as well as the minimum bactericidal concentration were 18.75 and 37.5 mg/ml, respectively. The concentration of 18.75 mg/ml significantly reduced biofilm adhesion. The results obtained from the evaluation of the antioxidant property showed that EPS indicated good antioxidant properties at much lower concentrations (4 mg/ml).