Glutinosin: a fungistatic metabolic product of the mould Metarrhizium glutinosum S. Pope

Abstract

Culture media on which the fungus Metarrhizium glutinosum has grown are highly toxic to other fungi. The fungus grows well on such standard synthetic media as Czapek-Dox or Raulin-Thom, but use of a crude grade of glucose instead of pure dextrose encourages sporulation and slightly increases the fungistatic activity of culture filtrates. It has been shown that yeast extract, biotin and aneurin supplements to a pure dextrose medium produce a similar response. In a study of the nature of the nitrogen source in the culture medium in relation to production of fungistatic culture filtrates, it has been found that nitrate nitrogen is very effective for growth of the fungus but not very effective for production of the fungistatic substance. Inorganic ammonium salts are ineffective in both respects, but peptone or ammonium tartrate were found to be highly effective both for growth and production of the fungistatic substance.