Effects of (−)‐borneol on the growth and morphology of Aspergillus fumigatus and Epidermophyton floccosom

Antifungal activity of (−)-borneol against two filamentous fungi, Aspergillus fumigatus and Epidermophyton floccosum, and relevant morphological effects were studied. Mycelial growths of the fungi were inhibited at 0.1, 0.5 and 1 mg/ml of (−)-borneol in Sabouraud dextrose agar medium. The growth inhibition of the two filamentous fungi by (−)-borneol was shown by ultra-structural modifications visualized by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). FESEM images of treated mycelia showed interesting alterations of the hyphal surfaces, while TEM observations revealed more detailed changes in cell walls and cellular organelles when compared with the normal structures of the cells. The presence of ultra-structural modifications of filamentous fungi due to treatment with (−)-borneol strongly supported the hypothesis that (−)-borneol induced morphological changes in mycelia. Copyright © 2012 John Wiley & Sons, Ltd.