Aspergillus ustus

Abstract
A. ustus grew best on Czapek-Dox medium with 4% glucose and 0.1% Bacto-Yeast extract, at 28[degree] C. The antibiotic substance was extracted from the medium by various solvents. It inhibited growth of Mycobacterium tuberculosis and M. ranae in equal degree. It was weakly antibiotic against Staphylococcus and Streptocococcus and had no activity against Escherichia coli. The active agent was stable and relatively non-toxic to mice.