Comparative and quantitative studies of fungitoxicity against fungal spores and mycelia.

In studies on the mode of action of antifuingal agents, it may be valuable to reveal the difference in drug sensitivity between fungal spores and mycelia. Various methods employed in the evaluation of antifungal substances do not necessarily apply to the solution of this problem. For the estimation of "sporostatic" activity of an agent, the inhibitory effect on the course of germination of spores can be taken as a measure of (luantitative evaluation of the activity. On the other hand, the quantitation of growth inhibitory activity oni mycelia ("mycostatic" activity) of an agent is much more complicated. In the present experiment, mycelial fragments prepared from pellets formed in the submerged culture of a fungus were used for the quantitative evaluation of mycostatic as well as the "mycocidal" activities of a given agent. The mycelial fragments formed individual colonies on agar media. Therefore, techniques for bacteriostatic and bactericidal tests routinely employed could be easily modified to mycostatic and mycocidal tests.