SEM images of dried peppermint leaves were obtained for the untreated samples as well as for those extracted by OAHD (for 30 min), MAHD (for 30 min) and HD (for 60 min)after two different extraction methods: using salted water or salted hydro distillation method (SHD) and using distilled water or normal hydro distillation method (NHD). The leaves were freeze-dried using a freeze drier (Armfield, UK) and fixed on the aluminum sample holder and then sputtered with gold in a sputter coater (Polaron SC7640, UK). All the samples were examined with a scanning electron microscope (Cambridge,UK) under high-vacuum condition and at an accelerating volt-age of 20.0 kV and at a working distance of 7.5–9.5 mm (i.e. thedistance between the surface of the sample and the micro-scope lens).