Biochemical and antibacterial properties of essential oil from Teucrium polium using resazurin as the indicator of bacterial cell growth

Due to the side effects of chemical and synthetic antimicrobial agents and emerging increase inbacterial resistances, more studies have recently focused on characterization of novel potential natural antimicrobial agents of plant, animal and microbial sources. Such substances are thought to have more half life and fewer side effects. In the present study, biochemical composition and antibacterial effects of Teucrium polium essential oil have been evaluated against some bacterial pathogens of clinical importance. The chemical analysis of the essential oil by Gas chromatography/ mass spectrophotometer (GC/MS) shows the presence of 58 substances (90.48%) mainly including Bicyclodec-1-ene and 1,3-Cyclooctadiene Respectively. Minimum inhibitory concentration of the essential oil determined using resazurin as bacterial cell growth indicator shows the highest antimicrobial activities against Bacillus cereus and Pseudomonas aeruginosa. The highest MIC values were observed in cases of Escherichia coli and Salmonella typhimurium. These results indicate that this essential oil has a high potential of antibacterial effect and resazurin can be used as a good growth indicator for different bacterial pathogens. Therefore, it can be suggested to purify and evaluate the active substances of this essential oil for future application as antibacterial agent and food preservative to combat pathogenic and toxigenic microorganisms.