Amanita Research Articles

First report of the saprotrophic mushroom Amanita thiersii Pers. (Amanitaceae, Basidiomycota) in the state of Goiás, Central-West Brazil

Amanita is a group of mushrooms of medical and culinary interest. Amanita thiersii is a species that has been little reported regarding its areas of occurrence. It is known that records of A. thiersii have been reported in Argentina, Mexico, and the United States. Our study reports the first record of A. thiersii in Brazilian territory. The specimen was collected in an area of the Cerrado domain, specifically in a Cerradão with mixed sandy-saprolitic soil. The identification of the mushroom A. thiersii was performed using an identification key for the genus Amanita. This is the first report of Amanita thiersii in Brazilian territory, collected in the Central-West region, state of Goiás.

Detection and quantification of Amatoxin in wild mushrooms from North-East India using HPLC-PDA method for food safety purposes

Misidentification and ingestion of poisonous mushrooms pose significant threats to food safety, particularly in Mizoram, India, where over ten fatalities due to mushroom poisoning have been reported in the past decade (2013-2023). This study aimed to address this critical issue by identifying and quantifying the cause of death due to consumption of wild mushroom from Champhai district, Mizoram, India and to test the reliability of HPLC-PDA for detection and quantification of amatoxins. HPLC-PDA confirmed the presence of α-amanitin in Amanita virosa and Amanita bisporigera in the samples. α-amanitin is a water-soluble, heat-stable, and highly toxic cyclic octapeptide present in the genus Amanita, which includes Amanita phalloides, Amanita verna, and Amanita virosa. Amanitin cytotoxicity arises from the inhibition of RNA polymerases, namely RNA polymerase II, which obstructs mRNA production in kidney and liver cells. Validation of the method demonstrated good precision and accuracy, with LOD and LOQ values of 88 ng g-1 and 210 ng g-1, respectively. The method was successfully applied to quantify α-amanitin in ten wild mushroom samples, revealing its presence only in Amanita virosa (1.17 mg g-1) and Amanita bisporigera (1.91 mg g-1) species. These findings underscore the importance of accurate α-amanitin detection methods in ensuring food safety and public health, particularly in regions prone to mushroom poisoning incidents. It is noteworthy that this study marks the initial exploration for detection and quantification of α-amanitin from poisonous mushrooms found in the wild regions of Champhai district in Mizoram, representing the first report of such in the area.

Indogenous knowledge of macromycetes of the genus Amanita in Burkina Faso

Indogenous knowledge of macromycetes of the genus Amanita in Burkina Faso

Phylogenetic and morphological studies reveal large diversity and three new species in Amanita sect. Vaginatae (Agaricales, Basidiomycota) from Europe

European members of the species-rich sect. Vaginatae of the genus Amanita are studied focusing on Central (Austria, Hungary, N Italy and Romania), Western (France) and North European (Norway) collections. The combination of a 4-locus (nrDNA ITS, nrDNA LSU, RPB1 and TEF1-α) molecular phylogenetic analysis and a morphological approach resulted in the discovery of three new species: Amanita deflexa and A. griseofulva from stirps Fulva and A. opaca from stirps Coryli. Furthermore, the albinotic white forms of A. griseofulva (f. albida) and A. opaca (f. cettoi) are formally named. As a result of the comprehensive taxonomic revision of Amanita sect. Vaginatae, 370 newly generated sequences are deposited to GenBank, and 17 species new to Hungary are reported. This study provides another step towards understanding the taxonomy and diversity of Amanita section Vaginatae in Europe.

Analyzing DNA barcoding and identifying toxins caused by neurotoxic mushroom poisoning using liquid chromatography tandem mass spectrometry

Background: Neurotoxic mushroom poisoning often exhibits rapid symptom onset, typically attributed to compounds such as Ibotenic acid, which affect the central nervous system. This study addresses a new case of mushroom-related food poisoning in southern Thailand. Objective: The objectives are to determine the presence of ibotenic acid in cases of mushroom-related food poisoning utilizing liquid chromatography-tandem mass spectrometry (LC-MS/MS) and to identify toxic Amanita species implicated in these cases. Materials and methods: Remnant mushroom samples obtained from three clinically reported cases were used. Nucleotide similarity was compared against the rRNA/ ITS databases using NCBI BLAST search. Phylogenetic analyses were conducted using maximum likelihood (ML) and FastTree approaches. LC-MS/MS was employed to separate of Ibotenic acid, determine its molecular weight and perform precursor ion fragmentation. Results: Analysis of the rRNA/ITS databases revealed a high nucleotide similarity between suspected mushroom samples and Amanita digitosa. Detailed phylogenetic analysis confirmed that mushroom samples from the three poisoning cases clustered with A. digitosa. LC-MS/MS analysis showed the presence of ibotenic acid, with precursor ion (m/z 159) and product ion (m/z 113.1) as the major toxic substances. Clinically, patients poisoned by ibotenic acid-containing mushrooms exhibited a short latent period with symptoms of nausea, vomiting, vertigo, delirium, confusion, and fatigue. Conclusion: The genus Amanita comprises both edible and inedible species that produce several lethal toxins. The report of ibotenic acid in A. digitosa is a novel finding, valuable for food safety monitoring and healthcare decision-maker. This is especially notable due to the accuracy and rapidity of the analytical process.

Simple andrapid detection ofthree amatoxins andthree phallotoxins inhuman body fluids by UPLC-MS-MS andits application in15 poisoning cases.

Amatoxins and phallotoxins are toxic cyclopeptides found in the genus Amanita and are among the predominant causes of foodborne sickness and poisoning-related fatalities in China. This study introduces and validates a simple, rapid and cost-effective ultra-performance liquid chromatography-mass spectrometry method for the simultaneous determination and quantification of α-amanitin, β-amanitin, γ-amanitin, phallisacin, phallacidin and phalloidin in human blood and urine. Quick therapeutic decision-making is supported by a 9 min chromatographic separation performed on a Waters Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8 µm) using a gradient of high-performance liquid chromatography (HPLC)-grade water and methanol:0.005% formic acid. The analyte limit of quantification was 1-3 ng/mL in blood and 0.5-2 ng/mL in urine. Calibrations curves, prepared by spiking drug-free blood and urine, demonstrated acceptable linearity with mean correlation coefficients (r) greater than 0.99 for all phallotoxins and amatoxins. Acceptable intraday and interday precision (relative standard deviation <15%) and accuracy (bias, -4.8% to 13.0% for blood and-9.0% to 14.7% for urine) were achieved. The validated method was successfully applied to analyze 9 blood samples and 2 urine samples testing positive for amatoxins and/or phallotoxins. Amatoxins and/or phallotoxins were identified in each whole blood sample at a range of 1.12-5.63 ng/mL and in two urine samples from 1.01-9.27 ng/mL. The method has the benefits of simple sample preparation (protein precipitation) and wide analyte coverage, making it suitable for emergency quantitative surveillance toxicological analysis in clinics and forensic poisoning practice.

Diversity and taxonomy of the genus Amanita (Amanitaceae, Agaricales) in the Yanshan Mountains, Northern China.

Globally, the species of Amanita are key components of ectomycorrhizal ecosystems. Some of them are widely known as poisonous or edible fungi. Although many new Amanita species from China have been described, the species diversity of Yanshan Mountains remains unknown. We here describe three new species, namely, A. borealis sp. nov. (Sect. Amanita), A. brunneola sp. nov. (Sect. Caesareae), and A. yanshanensis sp. nov. (Sect. Validae), based on morphological observations and molecular phylogenetic analyses. In addition, nine known species, namely, A. caesareoides (Sect. Caesareae), A. chiui (Sect. Vaginatae), A. muscaria (Sect. Amanita), A. oberwinklerana (Sect. Roanokenses), A. ovalispora (Sect. Vaginatae), A. subglobosa (Sect. Amanita), A. subjunquillea (Sect. phalloideae), A. vaginata var. vaginata (Sect. Vaginatae), and A. virosa (Sect. phalloideae), were reported from Yanshan Mountains for the first time. Our results emphasize that China has a high diversity of Amanita species and that additional studies are required to understand the exact species number. These findings play a crucial role in Amanita toxin research and ecological conservation. This study investigated the areas where Amanita species-related research is lacking. The study also attempted to better understand Amanita distribution and thus contribute to related research. This study enriches the species diversity of Amanita in Yanshan Mountains and offers additional data supporting the macrofungal systematics, toxin research, and diversity and ecological studies of Amanita in future studies.

Determination of ibotenic acid and muscimol in species of the genus Amanita section Amanita from China

The genus Amanita sect. Amanita harbors approximately 150 species in the world, and 27 species have been recognized in China. Some of the species in China have continuously caused poisoning. The responsible toxins should be ibotenic acid (IBO) and muscimol (MUS). However, species of the section Amanita containing IBO and MUS and their systematic positions are unclear. In this study, the contents of IBO and MUS in 84 samples of 24 species in section Amanita were detected using UPLC‒MS/MS, and the distribution of toxin-containing species in the molecular phylogeny was analyzed by the combined (ITS, nrLSU, RPB2, TUB2 and TEF1-α) dataset using maximum likelihood (ML) analysis and Bayesian inference (BI). Our results indicated that 10 of the 24 species contained IBO and MUS ranging from 0.6125 to 32.0932 and 0.0056–5.8685 g/kg dry weight, respectively. Among these 10 species, the toxins of eight species, including Amanita altipes, A. concentrica, A. flavopantherina, A. griseopantherina, A. pseudopantherina, A. rubrovolvata, A. subglobosa and A. sychnopyramis, were detected for the first time. In addition, the IBO and MUS contents of A. subglobosa in different growth stages showed that both toxins decreased in the mature stage. The phylogenetic analysis showed that all species of sect. Amanita from China were divided into 5 groups. And IBO- and MUS-containing species were gathered in clades Ⅰ and Ⅳ, but not all of the species in the two clades contain the toxins. No presence of IBO and MUS in the species of clades Ⅱ, Ⅲ and Ⅴ were confirmed.

Into the void: ECM fungal communities involved in the succession from rockroses to oak stands

Oak forests accompanied by Cistus species are a common landscape in the Mediterranean basin. It is argued that Cistus dominated fields serve as recruitment areas for Quercus seedlings, as they help in the transmission of the fungal community through vegetative succession in these ecosystems. To test these assumptions, we analyzed the fungal community in terms of its richness and composition, taking into account the effects of host (Oaks vs. Cistus) and forest structure, mainly based on age. Edaphic variables related to the different structures were also analyzed to examine how they evolve through succession and relate to shifts in the fungal community. No differences in fungal richness were observed between old Cistus stands and younger Quercus, while a brief increase in ECM richness was observed. Community composition also showed a greater overlap between old Cistus and young Quercus stands. We suggest that the most important step in fungal transfer from one host to another is the shift from the oldest Cistus fields to the youngest Quercus stands, with the genera Amanita, Cortinarius, Lactarius, Inocybe, Russula, and Tomentella probably playing a major role. In summary, our work has also revealed the network of fungal community structure in the succession of Cistus to Oak stands, it would suggest that the fungi share niches and significantly enhance the ecological setting of the transition from Cistus to Oak stands.

Notes on Amanita section Validae in Hainan Island, China.

Hainan is the second largest island in China with the most extensive and well-preserved tropical forests and is also the largest island of the Indo Burma Biodiversity Hotspot. It provides in situ conservation for the unique ecosystem of the island. Recent studies have shown that there are diverse fungal species in Hainan. In this study, about 40 collections of the genus Amanita have been studied based on the morphology and molecular systematics, including 35 Chinese specimens (24 from Hainan, and eleven from other regions) and three specimens from other countries (Singapore and Malaysia). In total, five new species belonging to Amanita section Validae are described: A. cacaina, A. parvigrisea, A. pseudofritillaria, A. pseudosculpta, and A. yangii. Amanita parvifritillaria is recorded for the first time in Hainan. It is also the first report of this fungus occurring, outside Yunnan Province, China. Among the five new species, two are unique in this section because of the appendiculate pileus margin and the absence of an annulus. Based on these new findings, the diagnosis of the section Validae should be slightly modified to include a few species with appendiculate margin and the lack of annulus.

Three species of Amanita section Lepidella (Amanitaceae, Agaricales) from northern Thailand

The genus Amanita, comprising three subgenera and eleven sections, is one of the most species diverse genera within the class Agaricomycetes. To date, 54 species have been validly reported from Thailand. During surveys of macro-fungi in northern Thailand in 2019 and 2020, three Amanita species were collected and identified as the members of Amanita sect. Lepidella based on morphological and molecular data. Among the three species, two species were identified as A. aureofloccosa and A. manicata and A. aureofloccosa is reported as a new record in Thailand. Interestingly, the third species was distinct from all other known species within sect. Lepidella. We describe the third species as a new species, namely A. albicarnosa. All these three taxa are documented with morphological characteristics, a phylogenetic tree, line drawings, color photographs, and comparisons with morphologically similar taxa. A distributional map of the sampling sites and a key to the Thai species of Amanita sect. Lepidella are also provided.

Neotype of Amanita spissa var. laeta (Basidiomycota, Amanitaceae)

While studying the genus Amanita in Brazil, a specimen identified by J. Rick as Amanita spissa var. laeta was found. Its morphological analysis suggested that this material certainly corresponded to the one used in the protologue of this name. For this reason, it is designated here as the neotype.

In vivo and in vitro α-amanitin metabolism studies using molecular networking

Amanitin poisonings are among the most life-threatening mushroom poisonings, and are mainly caused by the genus Amanita. Hepatotoxicity is the hallmark of amanitins, powerful toxins contained in these mushrooms, and can require liver transplant. Among amatoxins, α-amanitin is the most studied. However, the hypothesis of a possible metabolism of amanitins is still controversial in this pathophysiology. Therefore, there is a need of clarification using cutting-edge tools allowing metabolism study. Molecular network has emerged as powerful tool allowing metabolism study through organization and representation of untargeted tandem mass spectrometry (MS/MS) data in a graphical form. The aim of this study is to investigate amanitin metabolism using molecular networking. In vivo (four positive amanitin urine samples) and in vitro (differentiated HepaRG cells supernatant incubated with α-amanitin 2 μM for 24 h) samples were extracted and analyzed by LC-HRMS/MS using a Q Exactive™ Orbitrap mass spectrometer. Using molecular networking on both in vitro and in vivo, we have demonstrated that α-amanitin does not undergo metabolism in human. Thus, we provide solid evidence that a possible production of amanitin metabolites cannot be involved in its toxicity pathways. These findings can help to settle the debate on amanitin metabolism and toxicity.

Novel Cyclic Peptides from Lethal Amanita Mushrooms through a Genome-Guided Approach.

Most species in the genus Amanita are ectomycorrhizal fungi comprising both edible and poisonous mushrooms. Some species produce potent cyclic peptide toxins, such as α-amanitin, which places them among the deadliest organisms known to mankind. These toxins and related cyclic peptides are encoded by genes of the “MSDIN” family (named after the first five amino acid residues of the precursor peptides), and it is largely unknown to what extent these genes are expressed in the basidiocarps. In the present study, Amanita rimosa and Amanita exitialis were sequenced through the PacBio and Illumina techniques. Together with our two previously sequenced genomes, Amanita subjunquillea and Amanita pallidorosea, in total, 46 previously unknown MSDIN genes were discovered. The expression of over 80% of the MSDIN genes was demonstrated in A. subjunquillea. Through a combination of genomics and mass spectrometry, 12 MSDIN genes were shown to produce novel cyclic peptides. To further confirm the results, three of the cyclic peptides were chemically synthesized. The tandem mass spectrometry (MS/MS) spectra of the natural and the synthetic peptides shared a majority of the fragment ions, demonstrating an identical structure between each peptide pair. Collectively, the results suggested that the genome-guided approach is reliable for identifying novel cyclic peptides in Amanita species and that there is a large peptide reservoir in these mushrooms.

Forensic differentiation of amanita mushrooms using atr-ftir spectroscopy coupled with chemometrics

In mushroom poisoning cases, genus Amanita is responsible for majority of fatalities. Most of such cases are due to the accidental consumption of inedible mushrooms, but there is a high probability of their use forhomicidal purposes. Mushroom species can be identified based on the morphological features, however, in the field of forensic science,available exhibits are recovered in trace amounts, which pose a serious challenge before the forensic experts to analyse the samples in a non-destructive manner. In current work, ATR FT-IR spectroscopy has been used for the non-destructive identification and differentiation of six species of genus Amanita. To distinguish the selected mushroom species, chemometric tools like PCA and PLS-DA were applied. All samples were not successfully classified using the PCA model, therefore the PLS-DA model was applied to enhance the classification rate. PLS-DA model yielded a significant classification rate for the differentiation among the samples of different wild mushroom species. Furthermore, blind validation test was conducted and all unknown samples were classified accurately to their respective class. The obtained R-square value for PLS-DA model was 0.99 which is highly significant for the prediction accuracy.

Mushroom Poisoning Outbreaks - China, 2020.

Summary What is already known about this topic? Acute liver failure, rhabdomyolysis, acute renal failure, and hemolysis caused by poisonous mushrooms are the most important mushroom poisoning threats to the Chinese population. The most notorious lethal mushrooms are the species from genera Amanita, Lepiota, and Galerina that cause acute liver failure, and Russula subnigricans that leads to rhabdomyolysis. What is added by this report? In 2020, the total number of investigations reached 676, involving an estimated 102 species of poisonous mushrooms, 24 of which were newly recorded in China. Gyromitra venenata was newly discovered in incidents in Yunnan and Guizhou provinces and were the first reported poisonings due to gyromitrins in China since 2000. The rare poisoning Shiitake mushroom dermatitis was recorded in China. Hemolysis poisoning caused by Paxillus involutus was recorded for the second time since the beginning of the new century, resulting in one death in Inner Mongolia Autonomous Region. What are the implications for public health practice? Promoting knowledge about safe consumption of mushrooms is essential to reduce mushroom poisonings. It is not wise to collect and eat wild mushrooms. For southwestern provinces such as Yunnan, especially, caution must be exercised with unfamiliar mushroom species.

Retke vrste iz roda Amanita zabeležene u okviru Specijalnog rezervata prirode "Goč-Gvozdac"

Five species of the genus Amanita Pers.: Amanita nivalis Grev, Amanita pini Neville &amp; Poumarat, Amanita friabilis (P. Karst.) Bas Amanita betulae Neville &amp; Poumarat and Amanita coryli f. albida Neville &amp; Poumarat., were observed during the research of macromycetes of the Special Nature Reserve "Goč-Gvozdac" in the period from 2014 to 2021. These are the first records of these species in Serbia. Since these species are rare in other European countries, this paper aims to contribute to a better knowledge of these species. Enclosed are the photographs taken at the site, macroscopic and microscopic descriptions of the species with corresponding photographs of the finds including comments relating to distribution, ecology and taxonomy.

Camera trap detection of mycophagy among co‐occurring vertebrates

AbstractThirty camera traps were deployed for a total of 4179 trap‐nights between January and June 2020 as part of a project assessing post‐fire recovery of pademelons (Thylogale spp.) in northern New South Wales. By chance, one camera documented a site that was highly productive for the ectomycorrhizal fungal genus Amanita. This camera provided a rare opportunity to document a diversity of co‐habitating vertebrates that utilise these ectomycorrhizal fungi for food and in turn perform an important ecosystem function through the dispersal of their spores. Our camera recorded eleven vertebrate species; of these, we captured photographic evidence of Australian brush‐turkeys (Alectura lathami), a parma wallaby (Notamacropus parma), long‐nosed bandicoots (Perameles nasuta), red‐legged pademelons (Thylogale stigmatica) and red‐necked pademelons (T. thetis) feeding on fungal fruiting bodies.

Macromycetes of the “Baydarsky” Nature Reserve

The article is the first summary on the macromycetes of the “Baydarsky” State Natural Landscape Reserve. The annotated list of macromycetes of the reserve includes 201 species of macromycetes from 97 genera, 45 families, 13 orders. The species composition of families Boletaceae (26 species), Russulaceae (22), Tricholomataceae (19), Agaricaceae (15) and Amanitaceae (12), genera Lactarius (14), Amanita (11), Tricholoma (9), Russula (8), Cortinarius and Ramaria (6 species each), Agaricus and Hygrophorus (5 species each) is found out most fully completed; the number of Boletales mushrooms in the volume of Boletus s. l. is 26 species. For the registered in the reserve 9 species, this is the first find in the Crimean Peninsula, and for 45 species this is the same one in the Sevastopol region. In the Red Book of the Russian Federation included 7 species, the Red Book of the Republic of the Crimea - 14, and the Red Book of the city of Sevastopol - 16.

Amanita in the Guineo-Congolian rainforest: Epitypes and new species from the Dja Biosphere Reserve, Cameroon

ABSTRACT Four epitypes and three new species of Amanita (Amanitaceae, Agaricales, Agaricomycetes, Basidiomycota) are described from Guineo-Congolian rainforests of Cameroon. Amanita echinulata, A. fulvopulverulenta, A. robusta, and A. bingensis are epitypified based on collections that are the first since the species were described nearly a century ago. Morphological features of the epitypes are described and enumerated. Amanita minima, Amanita luteolamellata, and A. goossensfontanae are described as new and added to the known macromycota of tropical Africa. Habit, habitat, and known distribution are provided for each species. Sequence data for the internal transcribed spacer (ITS) locus are provided for types and other collections of all taxa, and a molecular phylogenetic analysis across the genus Amanita corroborates morphology-based infrageneric placement for each.