مقایسه فعالیت ضد باکتریایی روغن اسانسی تیموس و آمپیسیلین در شرایط اینویترو

Many plants play important role in pharmaceutical, food, medicine and    cosmetic industries for their volatile oils. Numerous studies have been carried    out on various plant species and effect of their essential oils or extracts on    microorganisms. In the present study antibacterial effect of Iranian thyme    on two pathogens of E.coli and S.aureus, is reported for the first time.    Antibacterial property of thyme oil is compared with that of ampicillim.           Essential oil of Thymus x-porlock was extracted by steam distillation and    its antimicrobial effects on E.coli and S. aureus were studied. Disc diffusion    method was conducted to evaluate the zone of microbial growth inhibition.    The antibacterial effect was also studied against three different    concentrations of microbial suspension to find out MIC (Minimal Inhibitory    Concentration) and MBC (Minimal Bactericidal Concentration).The results    were compared with those of ampicillin.           Fresh oil from Thymus x-porlock at 1/16 and 1/8 dilutions inhibited E.coli      and S.aureus growth with 17mm and 22mm microbial growth inhibition    zones respectively.  Ampicillin at 4 mg/ml concentration was bactericidal    against E.coli showing 11mm zone of microbial growth inhibition. Ampicillin    was bactericidal against S.aureus at 6mg/ml concentration with 23mm    growth inhibition zone.           The essential oil of thyme showed a very good bactericidal activity    within shorter time than that of ampicillin.