A mutant strain of Aspergillus parasiticus lost its aflatoxin producing ability but produced four yellow pigments. The major one represented 0.13% of the mycelial mass and was identified as versicolorin A by comparison of its physical and chemical properties with those reported for an authentic compound. A trihydroxyanthraquinone, versicolo-

The major product formed from reacting pure aflatoxin B1 with ammonium hydroxide at 100°C under pressure was isolated in crystalline form. The compound, molecular weight 286 (mass spectra), ultraviolet (UV) absorption, λMe0H 227, 324 nm (ε 15,920, 12,440), is nonfluorescent, exhibits phenolic properties, and lacks the lactone group characteristic of aflatoxin B1. Acidification of the compound did not regenerate aflatoxin B^ Calculations made from UV absorption spectra indicate that this molecular weight 286 compound comprises about 30% of the crude ammoniation product. It is postulated that the new product, C16H14O5, arises from opening the lactone ring of aflatoxin B1 during ammoniation, formation of the ammonium salt of the resultant hydroxy acid, and loss of carbon dioxide from this β-keto acid. Because this compound arises from decarboxylation, the trivial name aflatoxin D1 is proposed.

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