The antioxidant capacity of essential oils of Mentha spicata L., Mentha x gentilis L., Mentha crispa L., Mentha piperita L. and Mentha x piperita L. was determined by using differential pulse voltammetry. This assay was based on the reduction in the limiting current value of the oxygen electroreduction, which was used to calculate the antioxidant capacity (K) of these species. The species M. x ...