Molecular identification of poisonous mushrooms using nuclear ITS region and peptide toxins: a retrospective study on fatal cases in Thailand

Abstract

Cases of mushroom poisoning in Thailand have increased annually. During 2008 to 2014, the cases reported to the National Institute of Health included 57 deaths; at least 15 died after ingestion of amanitas, the most common lethal wild mushrooms inhabited. Hence, the aims of this study were to identify mushroom samples from nine clinically reported cases during the 7-year study period based on nuclear ITS sequence data and diagnose lethal peptide toxins using a reversed phase LC-MS method. Nucleotide similarity was identified using BLAST search of the NCBI database and the Barcode of Life Database (BOLD). Clade characterization was performed by maximum likelihood and Bayesian phylogenetic approaches. Based on BLAST and BOLD reference databases our results yielded high nucleotide similarities of poisonous mushroom samples to A. exitialis and A. fuliginea. Detailed phylogenetic analyses showed that all mushroom samples fall into their current classification. Detection of the peptide toxins revealed the presence of amatoxins and phallotoxins in A. exitialis and A. fuliginea. In addition, toxic α-amanitin was identified in a new provisional species, Amanita sp.1, with the highest toxin quantity. Molecular identification confirmed that the mushrooms ingested by the patients were members of the lethal amanitas in the sections Amanita and Phalloideae. In Thailand, the presence of A. exitialis was reported here for the first time and all three poisonous mushroom species provided new and informative data for clinical studies.

Potential DNA barcodes for Melilotus species based on five single loci and their combinations

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Optimisation of biomass, exopolysaccharide and intracellular polysaccharide production from the mycelium of an identified <em>Ganoderma lucidum</em> strain QRS 5120 using response surface methodology

“…Molecular identification of a wild fungal sample is important to determine the species of the sample [22]. Thus, molecular identification was performed on wild G. lucidum .…”

Molecular identification and optimization of cultural conditions for mycelial biomass production of wild strain of Chlorophyllum molybdites (G.Mey) Massee from the Philippines

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