Mehdi Ghasemi - Department of Biology, Ardabil Branch, Islamic Azad University, Ardabil, Iran
Keyvan Radjabalizade - Department of Biology, Ardabil Branch, Islamic Azad University, Ardabil, Iran
Kia Gharari - Department of Biology, Germi Branch, Islamic Azad University, Germi, Iran
Hashem Yaghoobi - Department of Biology, Ardabil Branch, Islamic Azad University, Ardabil, Iran

Background: Most of the population in the different areas of world is affected by bacterial infections responsible for dental caries. Due to theimportance of traditional medicines derived from herbs used for dental problems, this study investigated in vitro antibacterial activity ofMentha longifolia essential oil from Ardabil, Iran, on Streptococcus mutans, Lactobacillus rhamnosus and Actinomyces viscosus, bacteria thatcause tooth decay.Materials and Methods: The volatile oil of Mentha longifolia leaves was extracted by hydrodistillation method using a Clevenger-type apparatus and analyzed by GC and GC/MS system.The antibacterial activity was evaluated by the disk diffusion susceptibility in dilutions of62.5, 125, 250, 500, 1000 and 2000

Streptococcus mutans, Lactobacillus rhamnosus, Actinomyces viscosus, Mentha longifolia