ABSTRACT Aspergillus parasiticus NRRL 2999 did not produce aflatoxins on peptone‐mineral salts medium, but did accumulate blue‐fluorescent material having Rf's on thin‐layer chromatographic plates similar to aflatoxins B1 and B2. The blue‐fluorescent material was ultimately resolved into nine compounds. The four major compounds were tentatively identified by mass spectrometry as deoxyaspergillic acid, flavocol, deoxydehydroxymutaaspergillic acid, and 2‐hydroxy‐3,6‐di‐sec‐butylpyrazine, blue‐fluorescent pyrazines that have previously been isolated from other aspergilli. Evaluation of AOAC‐ recommended solvent systems for aflatoxin analyses indicated that diethyl ether/methanol/water (98:1:1) was the best TLC solvent system for separating aflatoxins from interferring fluorescent material. Pyrazine production was inversely related to carbohydrate content of the medium. Care should be taken in evaluating aflatoxin analyses of material with high protein and low carbohydrate levels.
