E. adenophorum oil extracts had caused morphological and ultrastructural changes within P. myriotylum in a concentration-dependent manner. Results from the TEM are in agreement with light microscope observations. Oil extracts eliminated almost entirely cytoplasm and cellular organelles from hyphae. This suggested that the mode of antifungal activity of oil extracts of E. adenophorum is a result of the oil extracts targeting the fungal plasma membrane and endomembrane systems. Somewhat similar phenomena were observed in TEM studies by Tian et al. using Cinnamomun jensenianum essential oil on Aspergillus flavus, which is an oil abundant in terpenes . However, it was not clear whether E. adenophorum oil extracts destroy the membrane system directly by preventing membrane formation or indirectly by inducing new substance which damaged membrane integrity.