Aflatoxins B1, B2, G1, and G2: Separation and purification

Aflatoxins B₁, B₂, G₁, and G₂ have been separated on a series of chromatographic columns. Chromatography of crude products isolated from molded wheat and rice on silicic acid with washed chloroform:ethanol (99:1) gave relatively pure B₁. The rest of the column fractions containing predominantly G₁, along with B₁, B₂, and G₂, were pooled and fractionated on a Silica Gel G column. The mobile phase was washed chloroform:acetone:ethanol (97.3:2.0:0.75). Thin-layer chromatography was used to follow column development. Each of the aflatoxins was treated with either decolorizing carbon or copper carbonate to remove colored pigments, and rechromatographed on Silica Gel G. Crystalline aflatoxins were prepared from chloroform solutions by addition ofn-hexane, methanol, or ethanol. Presented at the AOCS Meeting, New Orleans, May 1967. No. Utiliz. Res. Dev. Div., ARS, USDA.