Evidence that phomopsins A and B are not the only toxic metabolites produced by Phomopsis leptostromiformis.

The toxicities of up to four different toxic preparations containing metabolites of Phomopsis leptostromiformis were examined in two experiments with sheep and one with rats. It was shown that the different toxic preparations containing similar amounts of phomopsin A varied substantially in toxicity. Crystalline phomopsin A was the least toxic. It is suggested that the increased toxicity of the other three preparations was due to the presence of toxic metabolites additional to phomopsins A and B. Evidence to support this suggestion is presented.