Phylogenetic analysis, morphological studies, element profiling, and muscarine detection reveal a new toxic Inosperma (Inocybaceae, Agaricales) species from tropical China.

Tropical Asian collections of Inosperma are usually poisonous mushrooms that have caused many poisoning incidents. However, the species diversity and the toxic mechanisms of these Inosperma species are still unclear. In this study, we describe the discovery of Inosperma wuzhishanense sp. nov. from Wuzhishan City, Hainan Province, tropical China. The new species was identified based on morphological and multi-locus (ITS, nrLSU, and RPB2) phylogenetic analyses. The new species is characterized by its reddish-brown pileus, fibrillose stipes with finely protruding fibrils, rather crowded lamellae, smooth and ellipsoid basidiospores, and mostly clavate, thin-walled cheilocystidia. The new species is phylogenetically nested in the Old World tropical clade 2 and is sister to the tropical Indian taxa I. akirnum. Detailed descriptions, color photos of the new species, and comparisons with its closely related species are provided. Additionally, the muscarine content of the new species was analyzed by ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). The muscarine contents ranged from 4,359.79 ± 83.87 mg/kg to 7,114.03 ± 76.55 mg/kg, 2,748.37 ± 106.85 mg/kg to 4,491.35 ± 467.21 mg/kg, and 2,301.36 ± 83.52 mg/kg to 2,775.90 ± 205.624 mg/kg in the stipe, pileus, and lamellae, respectively. The elemental composition and concentration were determined using inductively coupled plasma-mass spectrometry (ICP-MS). A total of 24 elements were detected. Among the heavy metals detected, arsenic showed the highest level of toxicity with a concentration of 36.76 ± 0.43 mg/kg.

A new species of Inosperma, and first record of I. afromelliolens (Inocybaceae, Fungi) from West Africa.

Here, we present the newly identified Inosperma macrocarpa and the first record of I. afromelliolens from West Africa. Inosperma macrocarpa is nested in an Old World Tropical clade, based on a molecular phylogeny inferred from the sequences of ITS, LSU, RPB2, and TEF1. Complete descriptions and illustrations, including photographs and line drawings, of the new species are presented. Morphological and molecular analyses based on collections from Benin confirmed the presence of I. afromelliolens in West Africa. Toxicity analysis showed that neither species contained muscarine, which further supports the hypothesis that the ability to produce muscarine is a derived trait of Inosperma.

Five new species of Inosperma from China: Morphological characteristics, phylogenetic analyses, and toxin detection.

Many species of Inosperma cause neurotoxic poisoning in humans after consumption around the world. However, the toxic species of Inosperma and its toxin content remain unclear. In the present study, we proposed five new Inosperma species from China, namely, I. longisporum, I. nivalellum, I. sphaerobulbosum, I. squamulosobrunneum, and I. squamulosohinnuleum. Morphological and molecular phylogenetic analyses based on three genes (ITS, nrLSU, rpb2) revealed that these taxa are independent species. A key to 17 species of Inosperma in China is provided. In addition, targeted screening for the most notorious mushroom neurotoxins, muscarine, psilocybin, ibotenic acid, and muscimol, in these five new species was performed by using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Our results show that the neurotoxin contents in these five species varied: I. sphaerobulbosum contains none of the tested neurotoxins; I. nivalellum is muscarine positive; I. longisporum and I. squamulosohinnuleum contain both ibotenic acid and muscimol, and I. squamulosobrunneum only contains muscimol; psilocybin was not detected in these five new species.

Toxin screening of Pseudosperma umbrinellum (Agaricals, Basidiomycota): First report of phalloidin in Inocybaceae mushroom.

Pseudosperma species are widely distributed worldwide. Many of them cause poisoning incidents every year, and the toxin responsible for poisoning is muscarine, which could stimulate the parasympathetic nervous system. This study established a method using multiwalled carbon nanotube purification and liquid chromatography-tandem mass spectrometry for the targeted screening of mushroom toxins (muscarine, isoxazole derivatives, tryptamine alkaloids, three amatoxins and three phallotoxins) from Pseudosperma umbrinellum, a common poisonous mushroom distributed in north and northwestern China. Surprisingly, in addition to muscarine, phalloidin was also detected in P. umbrinellum, and the contents were 3022.2 ± 604.4 to 4002.3 ± 804.6 mg/kg (k = 2; p = 95%) muscarine and 5.9 ± 1.2 to 9.3 ± 1.8 mg/kg (k = 2; p = 95%) phalloidin.

A New Muscarine-Containing Inosperma (Inocybaceae, Agaricales) Species Discovered From One Poisoning Incident Occurring in Tropical China.

Currently, mushroom poisoning still poses a huge problem to humans' health and life globally. Poisoning incidents caused by Inosperma spp. were reported continuously in tropical China in recent years. In this study, a new poisonous Inosperma species, discovered from a poisoning incident, was described in tropical China based on morphological, molecular, and toxin detection evidence; detailed descriptions, photographs, and comparisons to closely related species were provided. For qualitative analysis, through targeted screening using ultra-high liquid chromatography triple quadrupole mass spectrometry (UPLC-MS/MS), the new species contains muscarine and no other toxins (two isoxazole derivatives, two tryptamine alkaloids, three amatoxins, and three phallotoxins). For quantitative analysis, muscarine contents in the pileus and the stipe were 2.08 ± 0.05 and 6.53 ± 1.88 g/kg, respectively.

Identification of Gyromitra infula: A Rapid and Visual Method Based on Loop-Mediated Isothermal Amplification.

With mushroom poisoning emerging as one of the most serious food safety problems worldwide, a rapid identification method of poisonous mushrooms is urgently required to investigate the source of poisoning. Gyromitra infula, a kind of poisonous mushroom, contains gyromitrin toxin, which causes epileptogenic neurotoxicity and hemolytic disease. This study aimed to establish a rapid and visual method of G. infula identification based on loop-mediated isothermal amplification (LAMP). A set of specific LAMP primers was designed, and its specificity in G. infula was confirmed against various mushroom species, including its closely related species and other macrofungi. The sensitivity assay showed that the minimum concentration of genomic DNA detected by LAMP was 1 ng/µl. The method's applicability was conducted by preparing mushroom samples that were boiled and digested in artificial gastric juice. The results showed that the content as low as 1% G. infula can be successfully detected. This method can be completed within 90 min, and the reaction results can be directly observed by the naked eyes. Hence, the identification method of G. infula established based on LAMP in this study is accurate, rapid, sensitive, and low-cost, which is required for clinical treatment or forensic analysis when mushroom poisoning occurs.

Iugisporipsathyrareticulopilea gen. et sp. nov. (Agaricales, Psathyrellaceae) from tropical China produces unique ridge-ornamented spores with an obvious suprahilar plage.

Iugisporipsathyra, a new psathyrelloid genus from tropical red soil of China, is established with I.reticulopilea as the type species. The new genus is characterised by basidiomata psathyrelloid, pileus rugose to appearing reticulate ridged, covered by persistent, but inconspicuous villus, pleurocystidia absent and ridge-ornamented spores with an obvious suprahilar plage. The genus is unique amongst Psathyrellaceae in producing ridge-ornamented spores with an obvious suprahilar plage and forms a distinct lineage within Psathyrellaceae, based on the Maximum Likelihood and Bayesian Inference analyses of a combined three-gene sequence dataset (ITS, LSU and ß-tub). Full descriptions and photographs of the new genus and species are presented.

 Pseudospermaarenarium (Inocybaceae), a new poisonous species from Eurasia, based on morphological, ecological, molecular and biochemical evidence.

In this study, Pseudospermaarenarium is proposed as a new species, based on morphological, ecological, molecular and biochemical evidence. The new species grows on sandy ground under Populus and Pinussylvestris in north-western China and northern Europe, respectively. It is characterised by the combination of the robust habit, nearly glabrous pileus, large cylindrical basidiospores, thin-walled cheilocystidia and ecological associations with Populusalba × P.berolinensis and Pinussylvestris and unique phylogenetic placement. Additionally, a comprehensive toxin determination of the new species using ultra-high performance liquid chromatography-tandem mass spectrometry was conducted. Results showed that it was a muscarine-positive species. The content were approximately five times higher in the pilei [4012.2 ± 803.1-4302.3 ± 863.2 mg/kg (k = 2, p = 95%)] than in the stipes [850.4 ± 171.1-929.1 ± 184.2 mg/kg (k = 2, p = 95%)], demonstrating the severity of mushroom poisoning when patients consumed different parts of the poisonous mushroom. Amatoxins, phallotoxins, ibotenic acid, muscimol, psilocybin and psilocin were not detected.

Two new Inosperma (Inocybaceae) species with unexpected muscarine contents from tropical China.

An accurate identification of poisonous mushrooms and the confirmation of the toxins involved are both of great importance in the treatment of mushroom poisoning incidents. In recent years, cases of mushroom poisoning by Inosperma spp. have been repeatedly reported from tropical Asia. It is urgent to know the real species diversity of Inosperma in this region. In the present study, we proposed two new Inosperma species from tropical Asia, namely I.muscarium and I.hainanense. They were described based on morphology and multilocus phylogeny. Detailed descriptions, color photographs and the discussion with other closely related species of the two new taxa were provided. In addition, a comprehensive muscarine determination of these two new species using ultrahigh performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) approach has been performed. Results showed that these two species were muscarine positive, with a content of 16.03 ± 1.23 g/kg in I.muscarium and a content of 11.87 ± 3.02 g/kg in I.hainanense, much higher than the known species I.virosum. Recovery of muscarine ranged from 93.45% to 97.25%, and the average recovery is 95.56%.

Effect of Shading and Forest Type on Morphological Characteristics and Bioactive Compounds of Fruiting Bodies of Songshan Lingzhi Ganoderma tsugae (Agaricomycetes).

Ganoderma tsugae strain MCCCMAS0053 cultivation on short logs results in varied yield and quality under different growth conditions. Thus, growth conditions need optimization to increase yield and quality. An indoor experiment with three shade treatments (A1, two layers of black sun-shade net; A2, one layer of black sun-shade net plus plastic mulch; A3, one layer of black sun-shade net) and a field experiment in two forest types (pine or mixed pine-oak) were conducted. The results showed that shading and forest type significantly affected light intensities and the growth, size, biomass, and bioactive components of G. tsugae fruiting bodies. In the indoor experiment, the mean dry weight of the fruiting body and the diameter of the pileus in A2 increased by 21.51-44.98% and 13.42-22.26%, respectively, compared with those of A1 and A3. Similarly, the accumulation of the bioactive compounds (polysaccharides, total amino acids, and total essential amino acids) in the pileus and stipe were greater in A2 than in A1 and A3. Furthermore, compared with pure pine forest cultivation, fruiting bodies cultivated in mixed pine-oak forest had greater dry weight, pileus diameter, and more bioactive compounds. In addition, no significant difference was found between the A2 and mixed pine-oak treatments, which had a similar light intensity (from 1116 to 2367 lx). Hence, this suggests that the A2 shade treatment or cultivation in mixed pine-oak forest is beneficial for production of G. tsugae fruiting bodies, and light intensity may play a critical role in this process.