Antibacterial Potential of Essential Oils From Melaleuca Alternifolia, Mentha Piperita, and Rosmarinus Officinalis Against Staphylococcus Pseudintermedius Isolates

Staphylococcus pseudintermedius is the main opportunistic agent related to canine pyoderma, composing the natural microbiota of hair follicles. It is considered the main cause of the use of antibiotics in small animals. Reports of methicillin-resistant S. pseudintermedius (MRSP) have become frequent in the veterinary clinical routine of small animals. Essential oils (EOs) have been studied and become a therapeutic alternative. The in vitro antibacterial activity of Melaleuca alternifolia, Mentha piperita, and Rosmarinus officinalis EOs against MRSP isolates and methicillin-susceptible S. pseudintermedius (MSSP) was evaluated. Assays were performed using the broth microdilution assay aiming for minimum inhibitory concentrations (MIC). Different concentrations of the EOs were placed (31.25 to 64000 μg/ml). The MIC values of the EOs from M. alternifolia, M. piperita, and R. officinalis against MRSP isolate were 10667, 32000, and 42666 μg/ml, respectively. M. piperita (EOMP) showed the lowest MIC value (5333 μg/ml) and EOMA from M. alternifolia showed the highest MIC value (37333 μg/ml) against MSSP. Therefore, the antibacterial effectiveness of the EOs can be considered for further therapeutic use.