Antimicrobial Effect of Methanolic and Acetonic of Zataria Multiflora, Capsicum Annum L. and Piper Nigrum L. Extracts on Pseudomonas aeruginosa Strains Isolated from Patients Hospitalized in the Burn Ward of Shahid Motahari Hospital in Tehran

Background: Pseudomonas aeruginosa (P. aeruginosa) is one of the main causes of nosocomial infection. Burn patients are at high risk of acquiring this bacterium due to skin damage and their immune deficiency, and mortality rate in these infected patients is high (40-50%). Therefore, due to antibiotic resistance of MBL containing strains in this bacterium, the aim of this study is to investigate the effect of methanol and acetone of Zataria multiflora, Capsicum annum L. and Piper nigrum L. on strains containing MBL in this bacterium. M aterials and Methods: This lab study was conducted on samples from burn patients, which were gathered between 2015 and 2016. In this study first, disc diffusion and MIC were done based on the CLSI protocol; and using a combined disk, we detected metallo-beta-lactamase. Next, the bla (IMP) and bla (VIM) genes were identified by the PCR method. In order to investigate the effect of three plants extract on bacteria, the bacteria was affected by triple extracts using MIC and disk diffusion. R es ults: According to the results, all three plants had an acceptable effect on Pseudomonas aeruginosa strains containing metallo-beta-lactamase, and to be more precise, the acetone type of extract of Capsicum Annum L at a concentration of 1.5 mg / ml had the best effect in treating of these bacteria. C onclusion: The results of this study indicate the presence of several mechanisms of resistance to beta-lactam antibiotics among Pseudomonas aeruginosa strains collected from burn patients. The emergence of these types of XDRs has led to health problems, especially in burn patients. According to the results, the methanolic and acetonic extract of all three plants have been shown to be effective in inhibiting the growth of MBL-containing Pseudomonas aeruginosa .