Antibiotic effects of some aquatic hyphomycetes

<e1>In vitro</e1>, antibiotic effects of the culture filtrates of 29 species of aquatic hyphomycetes against Gram-negative and Gram-positive bacteria, yeasts and hyphomycetes were studied. The culture filtrates of 38% of isolates were active in at least one of our tests for biological activity. Fifteen species inhibited growth of bacteria and four demonstrated antifungal activity. Filtrates of 35% of the isolates were antibacterial. About 50% of the isolates, those with the largest <e1>in vitro</e1> inhibitory activities (<e1>Dimorphosphora foliicola</e1>, <e1>Flagellospora</e1> sp. and <e1>Mycocentrospora</e1> sp.) were obtained from wood. Filtrates of <e1>Articulospora tetracladia</e1> were not only active against Gram −ve bacteria, but were also antiviral against bacteriophage T4 and influenza virus.