Determining the Antibacterial Effect of Mentha Longifolia Essential Oil on Cariogenic Bacteria and Its Compounds: an in vitro Study

Continuous use of chemical agents to reduce the number of cariogenic bacteria leads to adverse effects; therefore, in recent years, many studies have focused on plant-based substances. This study explores the antibacterial effects of ( ) essential oil on ( ), ( ), and as cariogenic microorganisms and determines the compounds in it. In this experimental study, , , and Lactobacillus isolates were collected from the saliva samples of five children with severe early childhood caries (S-ECC). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of essential oil were determined by Broth microdilution method. Chlorhexidine 0.2% and phosphate-buffered normal saline (pH= 7.0) were used as positive and negative controls, respectively. The chemical composition of essential oil was evaluated by gas chromatography-mass spectrometry. The data were analyzed with a paired t-test and the below 0.05 was considered significant. The MIC and MBC ratios for were 3.12% and 6.25%, for were 6.25% and 12.5%, ​​and were 3.12% and 6.25%, respectively. Chemical analysis of essential oil showed that 34 various compounds. Piperitone oxide (27.59%), Transcariophylline (14.55%), and 2-cyclohexane-1-one (12.24%) were the major constituents. essential oil has both growth inhibitory and bactericidal effects on all the three species of bacteria. This antibacterial effect was similar against and Lactobacillus, which was greater than , thus, it can be used as a supplementary for caries prevention compounds.