In vitro Anti-bacterial, anti-biofilm formation activities and urease inhibitory effect of four medicinal plants of Lamiaceae family against Klebsiella pneumoniae

Introduction and Obejectives: Klebsiella pneumoniae is among the most frequently recovered from nosocomial infections. This opportunistic pathogen has a high potential for antibiotic resistance and also it can generate a thick layer of biofilm. Antibiotic resistant strains were emerging and widely spread worldwide. Thus, it is necessary to combat drug resistant strains through the use of novel drugs. Some medicinal plants possess remarkable activity against bacterial agents. Among them, Lamiaceae family are in pharmaceutical interest. So, the aim of the study was to evaluate the in vitro antibacterial and anti-biofilm formation activities of Satureja rechingeri, S. khuzestanica, S. bachtiarica and S. mutica essential oils against K. pneumoniae. Materials and Methods: The Essential oils were obtained from Medicinal Herbs Research Center of Tehran. The tested strain was a standard strain of K. pneumoniae ATCC700603 For evaluation of the minimum inhibitory concentration (MIC) of essential oils, the microdilution method was used. Also standard method was used for evaluation of anti-biofilm activities of Sub-MIC value of essential oils. Colorimetric and Iodometric assays were used for determination of urease and betalactamas activity. Results: According to our data, the MIC value of essential oils was 4096μg/ml. Sub-MIC value of essential oils were inhibited biofilm formation of K. pneumoniae. But S. khuzestanica had more activity and S. mutica had less activity than others. Also, urease activity of K. pneumoniae was inhibited by sub-MIC value of all tested oils. Conclusion: According to our analysis S. khuzestanica had a good antibacterial, anti-biofilm formation activities and urease inhibitory effects against K. pneumoniae, but additional studies and researches is required to explore the exact mechanisms of the antibacterial action and functions of this phytocompound.

Keywords:

K. pneumoniae , Lamiaceae , Satureja , S. khuzestanica , anti-biofilm