Stability of necatorin, a highly mutagenic compound from Lactarius necator mushroom.

The mutagenic compound necatorin [7-hydroxycoumaro(5,6-c)cinnoline] was present in fresh Lactarius necator mushrooms at concentrations ranging from 3 to 20 mg/kg. Blanching decreased the concentration of necatorin in the mushrooms to about 25% of the original value. Pure necatorin was shown to be susceptible to decomposition by light, especially at high pH. The destruction of pure necatorin by boiling was most effective at pH 5.0, whereas at the other pH values studied (0.5 and 13.5) necatorin was relatively stable during boiling.