Efficacy of Azadirachta indica organic extracts against clinical methicillin resistant Staphylococcus aureus isolates

In current study we investigated the efficacy of organic extracts of Azadirachta indica leaves against Methicillin Resistant Staphylococcus aureus (MRSA) clinical isolates. For this purpose fresh leaves were used to prepare ethanol, methanol and chloroform extract. Secondly, a cross sectional study was conducted to isolate MRSA in clinical samples from patients having surgical/ non-surgical wounds from Allied Hospital and District Head Quarter Hospital, Faisalabad. The S. aureus isolates were initially identified by biochemical characterization, followed by identification of MRSA using cefoxitin disc diffusion test that was finally confirmed by genomic amplification of mecA gene, responsible for resistance. All MRSA isolates were tested to find vancomycin resistant S. aureus (VRSA) using E-strips (M.I.C. Evaluator^TM, Oxide, UK). The data showed an overall 37% prevalence of S. aureus including 56.75% clinical MRSA isolates while none of the isolated S. aureus showed resistance to vancomycin. The antimicrobial activity was measured as mean zone of inhibition for each extract against all MRSA isolates and it was found as 15.38±2.26, 16.09±3.09 and 17.42±2.48 for methanol, ethanol and chloroform extracts respectively. Chloroform extract showed significantly high antimicrobial activity against MRSA isolates. Altogether, the current study exposed the high prevalence of MRSA isolates from tertiary care hospitals. However, all MRSA isolates were found susceptible to organic extracts of A. indica leaves.