In vitro antibacterial activity and major bioactive components of Cinnamomum verum essential oils against cariogenic bacteria,Streptococcus mutans and Streptococcus sobrinus

Objective:To evaluate the antibacterial activity of Cinnamomum verum(C.verum) from32 different essential oils against cariogenic bacteria,Streptococcus mutans(S.mutans)and Streptococcus sobrinus(S.sobrinus).Methods:The antibacterial activities of each essential oil were individually investigated against S.mutans and S.sobrinus.The essential oil of C.verum was selected for further evaluation against S.mutans and S.sobrinus.Gas chromatography mass spectrometry was used to determine the major constituents of C.verum essential oil.In addition,the minimum inhibitory concentration(MIC) and minimum bactericidal concentration of the most effective constituent was investigated.Results:The essential oil from C.verum exhibited the greatest antibacterial activity.Gas chromatography mass spectrometry analysis revealed that the major components of C.verum essential oil were cinnamaldehyde(56.3%),cinnamyl acetate(7.1%) and bphellandrene(6.3%).The MIC of cinnamaldehyde was measured using broth dilution assays.The MIC of cinnamaldehyde was 0.02%(v/v) against both bacterial strains tested.The minimum bactericidal concentration of cinnamaldehyde against S.mutans and S.sobrinus were 0.2% and 0.1%(v/v),respectively.Conclusions:The essential oil of C.verum and its major component cinnamaldehyde possessed considerable in vitro antibacterial activities against cariogenic bacteria,S.mutans and S.sobrinus strains.These results showed that the essential oil of C.verum and its bioactive component,cinnamaldehyde,have potential for application as natural agents for the prevention and treatment of dental caries.

Biofilm Formation by <i>Streptococcus mutans</i>and Related Bacteria

Caries is a disease of human dentition characterized by the loss of mineralized surfaces of the tooth;it is an infectious disease of the oral cavity in which biofilms play a causative role. Control of biofilms has traditionally relied on non-specific removal of plaque by mechanical means such as brushing, although it is difficult to remove biofilms by this method. Caries is also a widespread infection in children. Streptococcus mutans and S. sobrinus are important causative agents of caries. They produce a homologous exocellular polysaccharide called glucan, which strongly adheres to the enamel surface. This is a review of oral microbial biofilm formation by S. mutans and other related bacteria.