Antibacterial effect of essential oils from Salvia leriifolia Benth. against some oral pathogens

Salvia leriifolia Benth. is a native medicinal plant species of Razavi Khorasan province, which possess valuable pharmacological properties including anti-microbial, anti-inflammatory, antioxidant, analgesic and sedative activities. In this study (basic/applied), antibacterial activity of essential oils from S. leriifolia against anaerobic bacteria cause oral-pharynx infections was investigated.
Aerial parts of S. leriifolia were collected at flowering stage from Bajestan in Razavi Khorasan Province. Essential oils were obtained using stem distillation methods and were analysed by GC-MS. Effects of different concentrations of essential oils (6.25, 12.5, 25 and 50 mg/ml) against Streptococcus mutans, Streptococcus pyogenes, Streptococcus sanguis and Actinomyces viscosus were evaluated by agar disk diffusion, hole-plate diffusion, common calibrated, agar dilution and broth dilution methods.
Among 35 compounds identified in S. leriifolia essential oils, β-pinene (23.35%), α-muurolol (17.11%), α-pinene (14.13%) and 1,8 cineole (13.25%) were the main compounds, respectively. Essential oil of S. leriifolia had significant inhibitory effect on the growth of all bacteria in a dose- dependent manner, so that maximum inhibitory effect was observed at concentration of 50 mg/ml. S. mutans (MBC=31.99 mg/ml, MIC=13.98 mg/ml) was the most sensitive bacterium and S. pyogenes (MBC=51.99 mg/ml, MIC=25.32 mg/ml) was the most resistance one.
Essential oils of Salvia leriifolia can be used as a natural product in herbal mouthwashes to control oral pathogens.