The effect of a surfactant in media for the enumeration, growth and identification of airborne fungi

Air sampling on to culture media for viable fungi is complicated by the presence of fast-growing species. A non-ionic surfactant (Triton N-101) incorporated into the medium effectively reduced the spread of such species and thus facilitated the enumeration and identification of fungal colonies collected by an Andersen sampler. The concentration of surfactant from 250 to 8000 ppm was not critical. Sixteen species of common moulds inoculated on surfactant media showed restricted radial growth but never total inhibition. Surfactant did not prevent sporulation and did not greatly affect morphological characteristics. Rose bengal media performed poorly in comparative tests. These observations indicate the practical value of this surfactant in aeromycological studies.