Impact of Commiphora myrrha on bacteria (Streptococcus mutans and Lactobacillus species) related to dental caries

Dental caries is a chronic disease caused by the interaction of oral microorganisms, diet and host factors over time. Streptococcus mutans is considered as the main bacteria involve in dental decay, while the level of Lactobacillus spp. is directly related to the presence or onset of caries. Commiphora myrrha is an ancient plant which extracts are used as antiseptic and anti-inflammatory for mouth and throat due to it is antimicrobial activity. This study assessed the impact of Commiphora myrrha on two bacteria Streptococcus mutans and Lactobacillus spp. involved in dental caries. Three samples of Streptococcus mutans bacteria were collected randomly from patients with dental caries in Khartoum dental teaching hospital, while Lactobacillus spp. were obtained from fermented milk. Disk and well diffusion methods were used to test the effect of four concentration (100,50,25 and 12.5 mg/ml) of Myrrha volatile oil, extracted by hydro-distillation technique. The biochemical analysis of Commiphora myrrha oil was carried out using Gas Chromatography/Mass Spectrophotometric technique. The finding revealed that the four concentrations of oil were effective on Streptococcus mutans with the largest inhibition zone (18.7{+/-} 0.6 mm) through the well diffusion method and inhibition zone of (14.00 mm) with disc diffusion method regardless the two methods these inhibition zones were recorded at 100 mg/ml, with Minimum Bactericidal Concentration (MBC) at 3.125 mg/ml. While Lactobacillus spp. bacteria sensitive to three concentrations (100,50 and 25 mg/ml) and resistance to concentration 12.5 mg/ml, it is MBC found to be 25 mg/ml. In conclusion, this research revealed that Myrrh oil is effective on both S.mutans and Lactobacillus spp. Hence, Myrrha oil is a potential antibacterial product of interest in dental caries.