Identification of toxic oligopeptides inAmanita fungi employing capillary electrophoresis-electrospray ionization-mass spectrometry with positive and negative ion detection

Mushrooms to live or die: toxicity of some Basidiomycota using Artemia franciscana

Consumption of wild mushrooms has increased in recent years; however, not all of them are edible and there is no precise information on those that may cause poisoning. Therefore, studies to obtain data about their toxicity are needed. For this purpose, we used the brine shrimp Artemia franciscana, a crustacean employed in toxicity tests and with wide application in the toxin detection, including mycotoxins. Mushrooms were collected in the state of Jalisco, Mexico, with which aqueous extracts were prepared. Dilutions of the stock solution of each extract were made to final concentrations of 50, 100, 250, 500, and 1000 µg/mL. Potassium dichromate (PD) was used as positive control and artificial seawater as negative control. The median lethal dose (LD50) of extracts on nauplii of A. franciscana was calculated. The aqueous extracts obtained from Amanita amerivirosa, A. muscaria, Chlorophyllum molybdites, and Leucopaxillus amarus showed a LD50 < 70 µg/mL, similar to PD (LD50 = 37 µg/mL). This is the first indication of the probable toxicity of Leucopaxillus amarus in humans. Cantharellus cibarius and Scleroderma texense caused the lower toxicity to the nauplii. The brine shrimp bioassay was effective in evaluating the toxicity of Basidiomycota. Scleroderma texense has been reported to be toxic, but it was not for this crustacean nauplii, and probably not to humans either, as recent literature has reported.

Analytical methods for amatoxins: A comprehensive review

Amatoxins are toxic bicyclic octapeptides found in certain wild mushroom species, particularly Amanita phalloides. These mushrooms contain predominantly α- and β-amanitin, which can lead to severe health risks for humans and animals if ingested. Rapid and accurate identification of these toxins in mushroom and biological samples is crucial for diagnosing and treating mushroom poisoning. Analytical methods for the determination of amatoxins are critical to ensure food safety and prompt medical treatment. This review provides a comprehensive overview of the research literature on the determination of amatoxins in clinical specimens, biological and mushroom samples. We discuss the physicochemical properties of toxins, highlighting their influence on the choice of the analytical method and the importance of sample preparation, particularly solid-phase extraction with cartridges. Chromatographic methods are emphasised with a focus on liquid chromatography coupled to mass spectrometry as one of the most relevant analytical method for the determination of amatoxins in complex matrices. Furthermore, current trends and future perspectives in amatoxin detection are also suggested.

Amanitins in Wild Mushrooms: The Development of HPLC-UV-EC and HPLC-DAD-MS Methods for Food Safety Purposes

Mushroom poisoning remains a serious food safety and health concern in some parts of the world due to its morbidity and mortality. Identification of mushroom toxins at an early stage of suspected intoxication is crucial for a rapid therapeutic decision. In this study, a new extraction method was developed to determine α- and β-amanitin in mushroom samples collected from central Portugal. High-performance liquid chromatography with in-line ultraviolet and electrochemical detection was implemented to improve the specificity of the method. The method was fully validated for linearity (0.5-20.0 µg·mL^-1), sensitivity, recovery, and precision based on a matrix-matched calibration method. The limit of detection was 55 µg mL^-1 (UV) and 62 µg mL^-1 (EC) for α-amanitin and 64 µg mL^-1 (UV) and 24 µg mL^-1 (EC) for β-amanitin. Intra- and inter-day precision differences were less than 13%, and the recovery ratios ranged from 89% to 117%. The developed method was successfully applied to fourteen Amanita species (A. sp.) and compared with five edible mushroom samples after extraction with Oasis^® PRIME HLB cartridges without the conditioning and equilibration step. The results revealed that the A. phalloides mushrooms present the highest content of α- and β-amanitin, which is in line with the HPLC-DAD-MS. In sum, the developed analytical method could benefit food safety assessment and contribute to food-health security, as it is rapid, simple, sensitive, accurate, and selectively detects α- and β-amanitin in any mushroom samples.

Amatoxins (α- and β-Amanitin) and phallotoxin (Phalloidin) analyses in urines using high-resolution accurate mass LC-MS technology

Mycotoxin intoxications can result from the consumption of amatoxins like α- and β-amanitin or of phallotoxin, present in several toxic mushrooms like Amanita phalloides. To identify and quantify amatoxins and phallotoidin in biological matrixes, we developed a method using liquid chromatography coupled with an ultra-high-resolution and accurate mass instrument (liquid chromatography-high-resolution-mass spectrometry, LC-HR-MS), Q Exactive™ (Thermo Fisher). The method includes a simple solid-phase extraction of urine samples spiked with flurazepam as internal standard (IS), using Bond Elut Agilent Certify cartridges (C18, 200 mg, 3 mL). LC separation was performed on a C18 Accucore column (100 × 2.1 mm, 2.6 µm) using a gradient of 10 mM ammonium acetate buffer containing 0.1% (v/v) formic acid and of acetonitrile with 0.1% (v/v) formic acid. Separation of analytes was obtained in 7 min, with respective retention times for α-amanitin, β-amanitin, phalloidin and IS of 1.9, 1.7, 3.5 and 3.8 min, respectively. Quantitation on the LC-HR-MS system was performed by extracting the exact mass value of each protonated species using a 5-p.p.m. mass window, which was 919.3614, 920.3455, 789.3257 and 388.1586 for α-amanitin, β-amanitin, phalloidin and IS, respectively. Calibration curves were obtained by spiking drug-free urine at 1-100 ng/mL. Mean correlation coefficients, r(2), were above 0.99 for each amatoxins and phalloidin. According to currently accepted validation procedures, the method was tested for selectivity, calibration, accuracy, matrix effect, precision and recovery. Authentic urine samples from 43 patients suffering from a suspected intoxication with mushrooms were analyzed by LC-HR-MS, and the results were compared with ELISA competitive immunoassay. The LC-HR-MS presented large benefits over immunoassay of being specific, faster and more sensitive, making it suitable for daily emergency toxicological analysis.

Rapid genetic detection of ingested Amanita phalloides

Mushrooms are often poorly digested by humans. Thus, their remains (tissues, spores) may persist in the gastrointestinal tract and can be detected in feces several days after mushroom consumption. In this report, we present protocols for the rapid PCR-based detection of fungal traces in a variety of complex samples. Novel primers were designed to amplify portions of ribosomal DNA from deadly poisonous European members of the genus Amanita, namely the death cap (A. phalloides), the destroying angel (A. virosa) and the fool's mushroom (A. verna), respectively. Assay sensitivity was sufficient to discover diluted DNA traces in amounts below the genomic content of a single target mushroom cell. Specificity testing was performed with DNA extracts from a variety of mushroom species. Template amplification was exclusively observed with intended targets and it was not compromised by a vast excess of non-target DNA (i.e. DNA from human and human fecal origin, respectively). A series of experiments was conducted with prepared specimens in order to follow the course of mushroom food processing and digestion. Amplification by direct PCR was successful with raw, fried and digested mixed mushrooms. To improve assay performance with fecal samples, a rapid protocol for sample pre-processing (including water-ether sedimentation and bead beating) and a modified PCR reaction mix were applied. Thereby, it was possible to detect the presence of A. phalloides DNA in spiked feces as well as in clinical samples (vomit, stool) from two independent cases of suspected mushroom poisoning.

Bioactive Lipids Metabolites in Amanita Virosa

Thrombin is the key serine proteinase of the coagulation cascade and, therefore, a suitable target for inhibition of blood coagulation. An extract of Amanita virosa considerably inhibited thrombin (48%), but showed no inhibitory activity on trypsin. On the basis of inhibition selectivity between thrombin and trypsin and potency of thrombin inhibition, A. virosa constitutes a good starting material for the isolation of further compounds that are active against thrombin. Bioassay oriented fractionation of the extract of A. virosa led to the isolation of a complex mixture of triglycerides (TGs), monoacylglycerols (MAGs), free fatty acids (FAs) and ergosterol. The structures of the isolated lipids metabolites were determined on the basis of chemical and spectroscopic evidences.

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

In this review, selected applications of CE-MS in recent years have been highlighted for the separation, detection and determination of environmental pollutants and food contaminants in selected samples. Trace analysis by CE-MS of analytes such as low molecular mass amines, nitroaromatics, alkylphosphonic acids, azo dyes, antidepressants, and antibiotic drugs, among others, in air, sediment and water samples have been reviewed. The CE-MS analysis of pesticides such as triazolopyrimidine sulphoanilides, different types of antibiotics (sulphonamides, beta-lactones, quinolones and tetracyclines) and other exogenous compounds such as acrylamide and toxic oligopeptides in food samples has also been reviewed. The review gives details on the fragmentations, where available, that the ionic species exhibit in-source and in ion trap, triple quadrupole and ToF MS analysers. A critical evaluation is also given of these recent CE-MS analytical methods for the separation, detection and determination of trace levels of such pollutants and contaminants with analytical information on the treatment of the samples, CE separation conditions, linearity ranges, LODs and recoveries from the different matrices presented.

Recent food safety and food quality applications of CE-MS

The first on-line coupling of CE with MS detection more than 20 years ago provided a very powerful technique with a wide variety of applications, among which food analysis is of special interest, especially that dealing with food safety and food quality applications, the major topics of public interest nowadays. With this review article, we would like to show the most recent applications of CE-MS in both fields by recompiling and commenting articles published between January 2004 and October 2008. Although both applications are difficult to separate from each other, we have included in this work two main sections dealing with each specific field. Future trends will also be discussed.