Antibacterial effects of Extract of Rosemary (Rosmarinus officinalis) compared with five common antibiotics against E coli responsible for avian colibacillosis

Background and Aim : Antimicrobial therapy is an important tool in reducing colibacillosis. Nowadays, the increased use of synthetic antibiotics leads to the incidence of resistant strains and high side effects. Therefore, The use of antimicrobial properties of medicinal plants can solve common problems in the use of antibiotics. Rosemary (Rosmarinus officinalis) is a medicinal plant uses in traditional medicine that can considered as an appropriate alternative of antibiotics.Methods : The objective of present work was to evaluate antibacterial effects of Rosemary (Rosmarinus officinalis) on Escherichia coli isolated from broiler flocks with colibacillosis. The antimicrobial effects of alcoholic extract of Rosemary was obtained on the E. Coli isolates in a culture medium and Mueller Hinton agar using disc diffusion and microdilution methods and determination of microbial susceptibility was also performed by Bauer and Kirby method.Results : The antibiotics flomequine, neomycine, trimethoprim-sulfamethoxazole, doxycycline and lincospectin were used as positive control. The hydro-alcoholic extracts of rosemary at higher concentrations was active against Escherichia coli. The test results Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) Determined that Rosemary Extracts ompared with some this antibiotics are better antibacterial effect.Conclusion : The results showed that Rosemary has antimicrobial activity. Considering the increasing resistance to synthetic antibiotics, Rosemary as a potential source of new antibacterial substances can replace chemical drugs for treat infections.

Keywords:

Antibacterial effects , Rosmarinus officinalis , E. Coli , MIC