Structure Elucidation of a New Toxin from the Mushroom Cortinarius rubellus Using Gas Chromatography-Mass Spectrometry (GC-MS)

Abstract

Cortinarius orellanus (Fries) and C. rubellus (Cooke), which were formerly also known as C. speciosissimus, are poisonous mushrooms containing the toxin orellanine and several degradation products of orellanine, including orelline and orellinine. Mass intoxication by poisonous mushrooms was observed in Poland in 1952-1957 [1]. In 1957, the cause of these outbreaks was described by Grzymala as poisoning by a member of the Cortinarius family. The toxin orellanine was first isolated from C. orellanus by Grzymala in 1962; the chemical structure of orellanine was later determined to be 3,3¢,4,4¢-tetrahydroxy-2,2¢-bipyridine-N,N¢-dioxide. Poisoning with C. orellanus and C. rubellus has a very specific character. The first symptoms of intoxication usually do not appear until 2 - 3 days after ingestion, but in some cases intoxication appears after three weeks. The target organ for the toxin is the kidney. Histologically, it is easy to record the specific damage. The presence of degradation products of orellanine in kidney can be confirmed chromatographically, suggesting that the cause of poisoning is orellanine. However, the presence of orellanine in the blood of intoxicated persons has not been directly detected. A specific model was developed by Brondz et al. for the detection of orellanine, orelline, and orellinine in animal stomach fluids [2-4]. The hypothesis that the fungal toxin orellanine as a diglucoside can be transported from the digestive system by the blood to the kidney could not be supported. The toxin orellanine as a diglucoside is very unstable in an aqueous acidic environment. However, in the present study, it was possible to record an additional substance in animal stomach fluids using GC-MS after ingestion of C. rubellus. This substance, which has been named rubelline, is part of a toxic mixture in C. orellanus and C. rubellus and is closely related to orellanine.