Abstract
The optimum culture conditions for mycelial growth and aflatoxin production by a human pathogenic strain of A. flavus were established. On the basis of its physical and chemical properties, the toxin extracted from mycelia and culture filtrates was identified as aflatoxin B2. The organism produced maximum amounts of toxin after the 8th day of incubation in stationary culture at 30.degree. C in the dark. In basal medium with ammonium sulfate as the N source, at an optimum pH of 4.5, more aflatoxin was produced when sucrose rather than maltose or glucose was the C source. The optimum temperature for growth was 37.degree. C. Saprophytes reportedly showed optimum growth at 20-32.degree. C; the human pathogenic strain grew best at a higher temperature.