The antibacterial effects of vitamin D3 against mutans streptococci: an in vitro study

Abstract

PurposeThis study aims to evaluate the antimicrobial effects of the cholecalciferol vitaminD3 against Streptococcus sobrinus (Strep. sobrinus) and Streptococcus mutans (Strep.mutans) bacteria in vitro that is considered the main causative bacteria in dentalcaries development.Materials and MethodsThe antimicrobial effects of vitamin D3 were evaluated against Strep. sobrinusand Strep mutans using the agar disc diffusion method. The minimum inhibitoryconcentration (MIC) and minimum bactericidal concentration (MBC) of vitaminD3 were determined using a microdilution method following the guidelines bythe Clinical Laboratory Standards Institute (CLSI). Scanning electron microscope(SEM) was used to evaluate the morphological changes of bacterial cells followingexposure to vitamin D3.ResultsStrep. sobrinus was more sensitive to vitamin D3 compared to Strep. mutans bacteria.The MIC values of vitamin D3 against Strep. sobrinus and Strep. mutans were 60 μg/mL and 250 μg/mL respectively whereas the MBC values were 120 μg/mL and 500μg/mL, respectively. Moreover, significant changes in the bacterial morphologywere observed in treated bacterial cells with vitamin D3 as compared to theuntreated control bacteria using SEM.ConclusionThese findings suggested that vitamin D3 has excellent antimicrobial effects againstStrep. sobrinus and Strep. mutans and may be considered as a promising compoundin the prevention of dental caries in the future. Further research is recommended toelucidate the mechanism of vitamin D3 on these bacteria.