Isolation and purification of AAL-toxin from Alternaria alternata grown on rice.

An isolation and purification procedure is described for AAL-toxin, a secondary metabolite produced by Alternaria alternata. The method involves growth of the fungus on rice media, extraction with chloroform followed by methanol: water from fungus-infested rice, and purification of the aqueous layer that contains AAL-toxin by using chromatography methods. The AAL-toxin was of type A, and white in color, and its purity was > or = 95% with mol. wt 522 (M + 1).