Color Reaction Identification of Omphalotus guepiniformis Causing Food Poisoning

Simple identification using a color reaction was applied to investigate poisoning, putatively caused by Omphalotus guepiniformis. Some leftover uncooked mushrooms had turned turquoise green when a beam reagent (5 w/v% potassium hydroxide ethanolic solution) was dripped onto the mushroom pileus. Furthermore, ethanol extract of the mushrooms exhibited the same color reaction. Then, illudin S, a toxic compound contained in O. guepiniformis, was detected in uncooked leftover mushrooms using LC-MS/MS analysis. Therefore, this case was inferred as caused by O. guepiniformis. These results indicate the identification method described above as useful for screening tests for investigating food poisoning caused by O. guepiniformis.