Toxic properties of the mushroom Cortinarius orellanus

Abstract

The toxins of the mushrooms Cortinarius orellanus (Fries) and Cortinarius speciosissimus (Kühn & Romagn) were isolated by extraction procedures and Sephadex chromatography. All intermediate and end products of the purification process were tested in mice for acute toxicity after oral and i.p. administration. In both species a fluorescent main toxin and a nonfluorescent compound of minor toxicity were found. The main toxin of both species was identified by mass spectrometric and nuclear magnetic resonance analyses as the 2,2′-bipyridine- 3,3′,4,4′-tetrol-1,1′-dioxide, which is identical to orellanine. The purified compound was toxic when administered either orally or i.p. When given orally the LD₅₀ was 33 mg/kg body weight in mice. The oral LD₅₀ of Cortinarius orellanus (2.20 g dried mushroom/kg) and of Cortinarius speciosissimus (3.12 g/kg) depended on the orellanine content (14 mg/g in Cortinarius orellanus and 9 mg/g in Cortinarius speciosissimus). The second toxic component was ineffective in mice when given orally. It caused acute toxicity when administered i.p., but toxicity was low when compared to the main toxin. Thus it appears to be of minor importance. Intraperitoneal testing of both isolated toxins and of the extract containing the whole toxic potential of the mushrooms revealed that toxicity, time dependency and expression of toxicosis is accounted for by the sum of these two toxins. No peptidic main toxin as described by other mycologists could be detected.