Antibacterial Activity of Mentha piperita (Peppermint) Oil against Wound Infections Caused by Carbapenem-Resistant Klebsiella in Rats

Drug resistant Klebsiella pneumoniae causes nosocomial infections, pneumonia, wound sepsis and infections of newborns and intensive care patients. In many cases antibiotics are no longer very effective in patients treated for K. pneumoniae infections. Various studies have shown antimicrobial properties of essential oils and different compounds that are part of them. This study aimed to determine the antibacterial efficacy and minimum inhibitory concentration of the Mentha piperita essential oil against resistant strain of K. pneumoniae. Efficiency of peppermint oil when used with antibiotics in wound management as well as controlling K. pneumoniae infection was also investigated in this study. Well diffusion method was used to determine the antibacterial activity of peppermint oil, where its inhibitory capacity was observed along with antibiotics and compared with control. Bacterial load of K. pneumonia OXA48 resistant strain on wound in rat models was also studied and compared. Klebsiella pneumoniae OXA48 and K. pneumoniae ATCC 700603 were inhibited by effectively by 40 µl/ml of peppermint oil in well diffusion assays. In rat models the wounds were healed, and epithelization was quicker in 10% peppermint oil treated wounds. Wounds applied with a combination of peppermint oil and Imipenem were more effectively protected from infection and showed better healing as well. Peppermint oil depicted both inhibitory capacities against K. pneumonia OXA48 and promoted wound healing as well. Further studies regarding PMO and its efficacy in wound management as well as its associated molecular mechanism would provide better understanding regarding its potential.