Identification of toxic oligopeptides in Amanita fungi employing capillary electrophoresis‐electrospray ionization‐mass spectrometry with positive and negative ion detection

Abstract

The identification of toxic oligopeptides employing CE-ESI-MS is presented. The analytes studied ama- and phallotoxins are of significant forensic interest because over 90% of the lethal cases of fungus poisoning in man are caused by species of Amanita which contain these toxins. A CE method was developed to separate the toxins alpha-, beta- and gamma-amanitin, phalloidin and phallacidin. Their fragmentation patterns in MS(n) experiments were investigated in the positive and in the negative ion mode, also the influence of the sheath liquid mixture of the used interface on the S/N. Method validation included the determination of the LOD and the repeatability of the migration time and peak area for both detection modes. With the optimized method LODs of 13-79 ng/mL (17-87 nmol/L) were reached. The CE-MS procedure was successfully applied to the identification of ama- and phallotoxins in extracts of air-dried mushroom samples.

Capillary electrophoresis–mass spectrometry of intact basic proteins using Polybrene–dextran sulfate–Polybrene-coated capillaries: System optimization and performance

“…With the maturing of the interfacing technology in the last decade, CE-MS has been increasingly used for relatively fast measurements of complex samples requiring great resolving power. CE-MS has been applied in various fields such as proteomics [1], metabolomics [2] and forensic science [3], as well as for pharmaceutical [4] and food analysis [5]. CE-MS also exhibits interesting possibilities for the characterization of intact proteins, providing information on protein quality including isoforms, degradation products and impurities [6].…”

Simultaneous analysis of α-amanitin, β-amanitin, and phalloidin in toxic mushrooms by liquid chromatography coupled to time-of-flight mass spectrometry

“…Regarding the toxicity of phalloidin, there is a report insisting that the compound does not exert poisonous effects by its oral intake [1]. However, after parenteral administration of The analysis of amanitin(s) and/or phalloidin has been made using high-performance liquid chromatography [4−6], capillary electrophoresis, capillary electrophoresis coupled to mass spectrometry (MS) [7,8], and liquid chromatography (LC) coupled to MS or to tandem MS [9−11]. Although the latter LC-MS (-MS) methods seem to give the most reliable and sensitive results, each of the three reported methods [9−11] has its drawbacks.…”

The application of CE‐MS in the trace analysis of environmental pollutants and food contaminants

“…Almost all fatal human fungus poisonings are caused by one of the Amanita species, Amanita phalloides (''death cap''), which is the most frequent species found in Europe while the rarely found Amanita verna (''white death cap'') and Amanita virosa (''destroying angel'') prevail in the USA. Rittgen et al [60] have presented an interesting method for the identification of toxic oligopeptides (a-, b-and g-amanitin, phalloidin and phallacidin) employing CE-ESI-MS. The amatoxins have chemical structures composed of bicyclic octapeptides containing a central tryptophane ringsystem, a sulphide-bridge and an isoleucine side chain whereas the phallotoxins are bicyclic heptapeptides with an amatoxin-like structure.…”