Production of sterigmatocystin.

A procedure for the isolation of pure sterigmatocystin is described. It involves cultivation of an appropriate fungus on sterile maize, and extraction and column chromatographic purification of the crude extract. With this method sterigmatocystin may be obtained at a fraction of its commercial cost. Aspergillus versicolor seemed to be the best producer (5-12 g/kg) in 250 ml Erlenmeyer flasks. The yield dropped markedly with increasing flask size.