Microscopic studies of Candida albicans and Torulopsis glabrata after in vitro treatment with bifonazole. Light and scanning electron microscopy.

1-[(4-Biphenylyl)-phenylmethyl]-1H-imidazole (bifonazole, Bay h 4502, Mycospor) preferentially inhibited yeast-hypha conversion in the dimorphic fungus Candida albicans. As observed by phase-contrast and scanning electron microscopy the morphology of C. albicans yeast cells and Torulopsis glabrata cells markedly altered after treatment with bifonazole. Whereas control cells were mostly occurring singly, the bifonazole-treated cells did not separate, resulting in the formation of chains and clusters of interconnected cells. Furthermore, in contrast with control cells bifonazole-treated cells of C. albicans and T. glabrata were almost spherical in shape. Evidence is presented by means of fluorescence microscopy that bifonazole-treated yeast cells of C. albicans frequently lacked septa and often contained irregular deposition of chitin.