Background: This is the first report testing the antibiotic resistance-modifying activity of Mentha arvensis against MRSA (methicillin-resistant Staphylococcus aureus).
Materials and methods: In this study an ethanol extract of Mentha arvensis L. and chlorpromazine were tested for their antimicrobial activity alone or in combination with conventional antibiotics against MRSA strains.
Results: A potentiating effect of this extract on gentamicin, kanamycin and neomycin was demonstrated. Similarly, a potentiating effect of chlorpromazine on the same aminoglycosides was observed, indicating the involvement of an efflux system in the resistance to these antibiotics.
Conclusion: It is therefore suggested that extracts from M. arvensis could be used as a source of plant-derived natural products with resistance-modifying activity, such as in the case of aminoglycosides, constituting a new weapon against bacterial resistance to antibiotics, as with chlorpromazine.