Evaluation antioxidant activity, phytochemical constituents and antimicrobial of Mentha Piperita essential oil on some infectious and poisonous microorganisms

Mentha Piperita belonging to the family of Lamiaceae, is a usable medicinal herb that has therapeutic effects that essential oil has various applications in pharmaceutical industries and food. The aim of this study was to investigate the antioxidant properties, phytochemical constituents and antimicrobial effects of Mentha Piperita “in vitro”. Antioxidant activity was evaluated through 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and ß-carotene/linoleic acid assay. The essential oil was individually tested by disc diffusion assay and evaluating minimum inhibitory concentration (MIC) by method micro dilution broth and agar dilution. The minimum bactericidal/fungicidal concentration (MBC/MFC) and phytochemical constituents were tested. The results of the Kirby-Baur test showed that the maximum diameter of inhibition zone of Mentha piperita to the Candida albicans and the minimum zone diameter was associated with Salmonella typhi. The MIC of Mentha piperita for Staphylococcus epidermidis, Listeria innocua, Salmonella typhi and Candida albicans were 9.2, 18.4, 73.6 and 4.6 mg/ml, respectively. The IC50 and B-CL of Mentha piperita essential oil were equal to 1300 μg/ml and 41.3% respectively. Preliminary phytochemical analysis demonstrated the presence of most of the phytochemicals including flavonoids, saponins, flavone, saponins, tannins and alkaloids in the essential oil tested. Based on the present study, the essential oil from Mentha piperita antioxidant activity and antimicrobial activity against several clinical isolates tested and thus can be a good source of food industrial.