Influence of trace elements and nitrogen sources on versicolorin production by a mutant strain of Aspergillus parasiticus

Mycopathologia. 1979 Dec 28;69(3):161-6. doi: 10.1007/BF00452829.

Abstract

A mutant strain of Aspergillus parasiticus blocked in aflatoxin biosynthesis accumulates versicolorin A and versicolorin C. The effect of trace elements on the growth and versicolorin production by this strain was studied in a defined medium. The omission of manganese was slightly stimulatory to versicolorin production; when zinc was omitted from the medium, no detectable versicolorins were produced. Experiments on nitrogen sources in a high-sucrose medium indicated that fourfold to fivefold increases in versicolorin yields could be obtained by substituting 3 ml/l corn steep liquor or 0.1 M NH4NO3 for the 0.023 M (NH4)2SO3 used previously as the nitrogen source in studies on versicolorin production by this strain. These improved yields will facilitate attempts to accumulate enough versicolorin A and versicolorin C for toxicity and carcinogenicity testing. Chromatographic profiles of mycelial extracts of cultures grown in a defined medium with 0.1 M NH4NO3 as the nitrogen source revealed 2 previously unrecognized compounds. The accumulation of these new metabolites in a mutant blocked in aflatoxin production may indicate that they are biosynthetically related to aflatoxin.

MeSH terms

  • Anthraquinones / biosynthesis*
  • Aspergillus / drug effects
  • Aspergillus / metabolism*
  • Culture Media
  • Manganese / pharmacology
  • Mutation
  • Quaternary Ammonium Compounds / pharmacology*
  • Trace Elements / pharmacology*
  • Zinc / pharmacology

Substances

  • Anthraquinones
  • Culture Media
  • Quaternary Ammonium Compounds
  • Trace Elements
  • versicolorins
  • Manganese
  • Zinc