The number of poisoning cases caused by the Lepiota genus is globally increasing. This genus has more poisonous species than the Amanita genus, and many Lepiota species can cause severe toxicity and death if ingested. As recognized in the literature, L. castanea is a toxic species containing amatoxin. Although crude analytical methods have shown that L. castanea contains amatoxins, more recent and sensitive analyses suggest otherwise. Toxin concentrations can vary even among the same fungal species due to geographical and climatic differences. Therefore, this confusion can be resolved by analyzing L. castanea toxins from different geographical regions. This study aimed to demonstrate the toxin levels of L. castanea collected from forests in different regions of Turkiye (Istanbul and Kocaeli) using sensitive methods. The collected mushrooms were analyzed for alpha amanitin, beta amanitin, gamma amanitin, amanin, phallacidin, and phalloidin levels using RP-HPLC-UV and LC-ESI-MS/MS methods. L. castanea mushroom was found to be free of amatoxin and phallotoxin. Our study revealed for the first time that L. castanea mushrooms from different geographical regions of Turkiye do not contain amatoxin and phallotoxin. Supporting these findings with new studies from different parts of the world would be appropriate.

The discovery and identification of mushroom toxins has long been an important area in the fields of toxicology and food safety. Mushrooms are widely favored for their culinary and medicinal value; however, the presence of potentially lethal toxins in some species poses a substantial challenge in ensuring their safe consumption. Therefore, the development of a robust and sensitive analytical method is necessary for accurately identifying the risks associated with mushroom consumption. The study of mushroom toxins, which are characterized by their diversity and substantial variations in chemical structures, present a considerable challenge for achieving precise and high-throughput analysis. To address this issue, the present study employed a robust approach combining a solid-phase extraction (SPE) purification technique with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to establish an analytical method for the detection and quantification of five amatoxins and two tryptamines (psilocybin and bufotenine) present in some mushrooms. Several optimization procedures were undertaken, including optimizing the chromatographic conditions, mass spectrometric parameters, and sample extraction and purification. The procedure involved the extraction of dry mushroom powder with methanol containing 0.3% formic acid, followed by purification using a strong cation exchange cartridge (SCX). The analytes were separated on a T3 chromatographic column (100 mm×2.1 mm, 1.8 μm) using mobile phases of acetonitrile and 5 mmol/L ammonium acetate solution containing 0.1% formic acid. The multiple reaction monitoring (MRM) mode was employed for data acquisition. Amatoxins were quantified using matrix-matched standard calibration curves, whereas isotopic internal standards were used to quantify tryptamine. The results showed that all seven toxins exhibited good linearities (r2>0.99) within the optimized concentration range. The limits of detection (LODs) for bufotenine, psilocybin, and amatoxins were determined as 2.0, 5.0, and 10 μg/kg, respectively, while the limits of quantification (LOQs) were determined as 5.0, 10, and 20 μg/kg, respectively. The LOD and LOQ values further underscore the ability of the method to detect minute quantities of toxins, making it particularly well suited for screening food samples for potential contamination. Using dried shiitake mushroom powder as the matrix, the recoveries of the two tryptamines ranged from 80.6% to 117%, with relative standard deviations (RSDs) ranging from 1.73% to 5.98%, while the recoveries of amatoxins ranged from 71.8% to 115%, with RSDs varying from 2.14% to 9.92% at the three concentration levels. The consistent and satisfactory recoveries of amatoxins and tryptamines demonstrated the ability of this method to accurately quantify the target analytes even in a complex matrix. Comparison with the results of supplementary test method recognized by State Administration for Market Regulation for food (BJS 202008) demonstrated comparable results, indicating no significant differences (p>0.05) in amatoxin contents. The newly developed method is rapid, accurate, precise, meets the required standards, and is suitable for the detection of seven toxins in wild mushrooms. As part of the application of this method, a comprehensive investigation of the distribution of toxins in wild mushrooms from Fujian Province was undertaken. In this study, 59 wild mushroom samples from nine cities were collected in the Fujian province. Species identification was conducted using rDNA-internal transcribed space (rDNA-ITS) molecular barcode technology, which revealed the presence of toxins in the two samples. Notably, one specimen named Amanita fuligineoides contained α-amanitin, β-amanitin, and phalloidin in quantities of 607, 377, and 69.0 mg/kg, respectively. Additionally, another sample, identified as Tricholomataceae, had a psilocybin concentration of 12.6 mg/kg.

In Europe, amatoxin-containing mushrooms are responsible for most of the deadly poisonings caused by macrofungi. The present work presents a multidisciplinary revision of the European species of Amanita sect. Phalloideae based on morphology, phylogeny, epidemiology, and biochemistry of amatoxins and phallotoxins. Five distinct species of this section have been identified in Europe to date: A. phalloides, A. virosa, A. verna, the recently introduced North American species A. amerivirosa, and A. vidua sp. nov., which is a new name proposed for the KOH-negative Mediterranean species previously described as A. verna or A. decipiens by various authors. Epitypes or neotypes are selected for species lacking suitable reference collections, namely A. verna and A. virosa. Three additional taxa, Amanita decipiens, A. porrinensis, and A. virosa var. levipes are here considered later heterotypic synonyms of A. verna, A. phalloides, and A. amerivirosa, respectively.

Mushrooms containing Amanita peptide toxins are the major cause of mushroom poisoning, and lead to approximately 90% of deaths. Phallotoxins are the fastest toxin causing poisoning among Amanita peptide toxins. Thus, it is imperative to construct a highly sensitive quantification method for the rapid diagnosis of mushroom poisoning. In this study, we established a highly sensitive and automated magnetic bead (MB)-based chemiluminescence immunoassay (CLIA) for the early, rapid diagnosis of mushroom poisoning. The limits of detection (LODs) for phallotoxins were 0.010 ng/ml in human serum and 0.009 ng/ml in human urine. Recoveries ranged from 81.6 to 95.6% with a coefficient of variation <12.9%. Analysis of Amanita phalloides samples by the automated MB-based CLIA was in accordance with that of HPLC-MS/MS. The advantages the MB-based CLIA, high sensitivity, repeatability, and stability, were due to the use of MBs as immune carriers, chemiluminescence as a detection signal, and an integrated device to automate the whole process. Therefore, the proposed automated MB-based CLIA is a promising option for the early and rapid clinical diagnosis of mushroom poisoning.

About 95% of fatal mushroom poisonings worldwide are caused by amatoxins and phallotoxins mostly produced by species of Amanita, Galerina, and Lepiota. The genus Lepiota is supposed to include a high number of species producing amatoxins. In this study, we investigated 16 species of Lepiota based on 48 recently collected specimens for the presence of amatoxins by liquid chromatography coupled to a diode-array detector and mass spectrometry (UHPLC-QTOF-MS/MS). By comparing the retention times, UV absorptions, and diagnostic MS fragment ions with data obtained from the benchmark species Amanita phalloides, we detected α-amanitin and γ-amanitin in Lepiota subincarnata, α-amanitin and amaninamide in Lepiota brunneoincarnata, and β-amanitin and α-amanitin in Lepiota elaiophylla. Phallotoxins have not been detected any of these species. Two possibly undescribed amatoxin derivatives were found in Lepiota boudieri and L. elaiophylla, as well as one further non-amatoxin compound in one specimen of L. cf. boudieri. These compounds might be used to differentiate L. elaiophylla from L. xanthophylla and species within the L. boudieri species complex. No amatoxins were detected in L. aspera, L. castanea, L. clypeolaria, L. cristata, L. erminea, L. felina, L. fuscovinacea, L. lilacea, L. magnispora, L. oreadiformis, L. pseudolilacea, L. sp. (SeSa 5), and L. subalba. By combining the occurrence data of amatoxins with a phylogenetic analysis, a monophyletic group of amatoxin containing species of Lepiota is evident. These chemotaxonomic results highlight the relevance of systematic relationships for the occurrence of amatoxins and expand our knowledge about the toxicity of species of Lepiota.

Cell division in plants consists of separating the mother cell in two daughter cells by the centrifugal growth of a new wall. This process involves the reorganization of the structural elements of the cell, namely the microtubules and actin cytoskeleton which allow the coordination, the orientation, and the progression of mitosis. In addition to its implication in those plant-specific structures, the actin cytoskeleton, in close association with the plasma membrane, exhibits specific patterning at the cortex of the dividing cells, and might act as a signaling component. This review proposes an overview of the techniques available to visualize the actin cytoskeleton in fixed tissues or living cells during division, including electron, fluorescent, and super-resolution microscopy techniques.

Phallotoxins, toxic cyclopeptides found in wild poisonous mushrooms, are predominant causes of fatal food poisoning. For the early and rapid diagnosis mushroom toxin poisoning, a highly sensitive and robust monoclonal antibody (mAb) against phallotoxins was produced for the first time. The half-maximum inhibition concentration (IC50) values of the mAb-based indirect competitive ELISAs for phallacidin (PCD) and phalloidin (PHD) detection were 0.31 ng mL-1 and 0.35 ng mL-1, respectively. In response to the demand for rapid screening of the type of poisoning and accurate determination of the severity of poisoning, colloidal gold nanoparticle (GNP) and time-resolved fluorescent nanosphere (TRFN) based lateral flow assays (LFA) were developed. The GNP-LFA has a visual cut-off value of 3.0 ng mL-1 for phallotoxins in human urine sample. The TRFN-LFA provides a quantitative readout signal with detection limit of 0.1 ng mL-1 in human urine sample. In this study, urine samples without pretreatment were used directly for the LFA strip tests, and both two LFAs were able to accomplish analysis within 10 min. The results demonstrated that LFAs based on the newly produced, highly sensitive, and robust mAb were able to be used for both rapid qualitative screening of the type of poisoning and accurate quantitative determination of the severity of poisoning after accidental ingestion by patients of toxic mushrooms.

Many species of Amanita sect. Phalloideae (Fr.) Quél. cause death of people after consumption around the world. Amanita albolimbata, a new species of A. sect. Phalloideae from Benin, is described here. The taxon represents the first lethal species of A. sect. Phalloideae known from Benin. Morphology and molecular phylogenetic analyses based on five genes (ITS, nrLSU, rpb2, tef1-α, and β-tubulin) revealed that A. albolimbata is a distinct species. The species is characterized by its smooth, white pileus sometimes covered by a patchy volval remnant, a bulbous stipe with a white limbate volva, broadly ellipsoid to ellipsoid, amyloid basidiospores, and abundant inflated cells in the volva. Screening for the most notorious toxins by liquid chromatography-high-resolution mass spectrometry revealed the presence of α-amanitin, β-amanitin, and phallacidin in A. albolimbata.

A methodology based on the concepts that arise from Density Functional Theory (CDFT) was chosen for the calculation of the global and local reactivity descriptors of the Phallotoxin family of fungal peptides. The determination of the active sites for the molecules has been achieved by resorting some descriptors within Molecular Electron Density Theory (MEDT) like the Dual Descriptor and the Parr functions. Phallosacin has been found as the most reactive of the peptides on the basis of the calculated Global Reactivity Descriptors. The pKas of the seven studied peptides were established using a proposed relationship between this property and the calculated Global Hardness. The bioactivity properties of the peptides considered in this study were obtained by resorting to a homology model by comparison with the bioactivity of related molecules in their interaction with different receptors.

A fast and wide linear range method was established for the determination of mushroom toxins amanitins (α-amanitin,β-amanitin and γ-amanitin) and phallotoxins (phallacidin and phalloidin) in wild mushrooms by online liquid chromatography-diode array detector-tandem mass spectrometry (LC-DAD-MS/MS). The mushroom toxins were extracted with methanol, and diluted with water. The extracts were separated on an XBridgeTM BEH C18 column (150 mm×3.0 mm, 2.5 μm) under pH 10.7, measured by DAD and then analyzed by MS/MS. Basic mobile phase conditions were applied to improve the ionization efficiency of hydrogen ion adducts. The baseline separation of the analytes was obtained within 15 min. The limits of detection (LODs) of the sample matrix were 0.005-0.02 mg/kg. The toxins were quantified by the results measured by MS/MS when the toxin contents less than 2 mg/kg, and quantified by the results obtained from DAD when the contents more than 2 mg/kg. The linear range was 0.05-500 mg/kg for the whole method in one injection. The method was successfully applied to the analyses of amanitins and phallotoxins in Lepiota brunneoincarnata and white Amanita.