Anticariogenic Activity of Oregano against Streptococcus Mutans Biofilm for Investigating its Potential Use as an Oral Care Agent

Abstract

Being consumed as a spice, Origanum species are also utilized for alternative medical treatment and are therefore of great economic importance. This study examined the effect of Origanum vulgare L. subsp. gracile (OVG) essential oil (EO) against planktonic cell growth and biofilm formation of cariogenic Streptococcus mutansas well as its cytotoxic activity. The antimicrobial potential of EO was screened by broth microdilution method. Crystal violet (CV) biofilm assay method has been used to determine the antimicrobial activitiy and the biofilm formation was also displayed through scanning electron microscopy (SEM). The minimum inhibitory concentration (MIC) value of the EO was determined as 2.5±0.31 mg/mL. The EO acted as an anti-biofilm agent by preventing biofilm formation at sub-MIC concentrations (27.15 to 33.2%). The SEM imaging of biofilms treated with EO showed density and morphological changes when compared to the untreated group. To determine the cytotoxicity, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay wascarried out using the NIH-3T3 murine fibroblast cells andand exhibited IC50 value of 427±1.05 μg/mL.This study has shown that with strong antibacterial and antibofilm capacity, the EO of the OVG can be used as a potentialanticariogenicagent in the oral care products.