Trogia venenata (Agaricales), a novel poisonous species which has caused hundreds of deaths in southwestern China

About 400 unexplained sudden deaths have occurred in Yunnan Province in southwestern China during summers over the last 35?years. Extensive field investigations revealed that a fungus called ??little white mushroom?? or ??nail-like mushroom?? by the local people could be one of the chief causes. Fieldwork showed that this fungus is a common saprophytic species growing on rotten wood in southwestern, central, and northwestern Yunnan in subtropical mountainous areas between 1,700 and 3,000?m altitude. Morphological and molecular phylogenetic analyses revealed that it is a new species of the genus Trogia, closely related to the palaeotropical T. infundibuliformis and its allies. Accordingly, T. venenata is described and illustrated.     

Evidence for Inbreeding and Genetic Differentiation among Geographic Populations of the Saprophytic Mushroom Trogia venenata from Southwestern China

During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China.     

枝顶孢霉对毒光盖伞子实体形成的影响

报道枝顶孢霉Acremonium strictum对毒光盖伞Psilocybe venenata子实体形成的影响。拮抗试验结果表明它们之间存在着较弱的干扰竞争作用;人工培养时,毒光盖伞混合菌株产生大型、小型和畸形3种类型的子实体,推测毒光盖伞畸形子实体的形成可能是枝顶孢霉寄生的结果,为毒光盖伞的人工栽培和进一步合理利用、野生蕈菌的驯化提供了理论依据。     

Alstolenine, 19,20-dihydropolyneuridine and other minor alkaloids of the leaves of Alstonia venenata

Structures of alstolenine and 19,20-dihydropolyneuridine, two new indole alkaloids of the leaves of Alstonia venenata have been established. In add     

云南蘑菇中毒事件中的毒蘑菇物种多样性

近年来,云南省每年发生超过500起蘑菇中毒事件,造成2 000余人中毒,约30人死亡,成为我国蘑菇中毒危害最为严重的省份。系统研究蘑菇中毒事件中的毒蘑菇多样性,可以为蘑菇中毒精准防控提供科学依据和技术支撑。本研究对云南省2013年以来开展过科学物种鉴定的223起中毒事件进行了系统分析,发现云南省蘑菇中毒一年四季均有发生,主要集中在6-9月份,中毒事件数和中毒人数7月份达到高峰,而6月份死亡人数最多。地区分布分析发现云南省蘑菇中毒事件涉及14个市州,中毒事件数前5位分别为德宏、玉溪、保山、楚雄和普洱,均位于云南中部及以南地区。223起中毒事件中共成功鉴定出47种毒蘑菇,分属6种中毒类型(急性肝损害型、急性肾衰竭型、横纹肌溶解型、胃肠炎型、神经精神型和光敏性皮炎型)。这些毒蘑菇包含发现于中国的新物种16种,以及2019年以来发现的中国新记录种3种。致命鹅膏Amanita exitialis和亚稀褶红菇Russula subnigricans分别造成19人和9人死亡,是云南省最危险的2种剧毒蘑菇。青褶伞Chlorophyllum molybdites、日本红菇R. japonica、光硬皮马勃Scleroderma cepa、近江粉褶菌Entoloma omiense和发光类脐菇Omphalotus olearius位列胃肠炎型中毒的前5位。热带紫褐裸伞Gymnopilus dilepis、毒歧盖伞近似种Inosperma cf. virosum和兰茂牛肝菌Lanmaoa asiatica位列神经精神型中毒的前3位。叶状耳盘菌Cordierites frondosus是目前云南省造成光敏性皮炎型中毒的唯一物种。     

Echitoserpidine: A new alkaloid of the fruits of Alstonia venenata

The structure of echitoserpidine, a new alkaloid of the fruits of Alstonia venenata has been established as (1) on the basis of spectral and chemical evidence.     

5-Methoxy-1-oxo-tetrahydro-β-carboline,an alkaloid from Alstonia venenata

A new oxo-tetrahydro-β-carboline alkaloid has been isolated from the root bark of Alstonia venenata. It was identified as 5-methoxy-1-oxo-tetrahydro-β-carboline.     

16-Epivenenatine and 16-epialstovenine,new stereomers from Alstonia venenata

16-Epivenenatine and 16-epialstovenine have been isolated from Alstonia venenata. The structures and stereochemistry of these two new bases have been determined from spectral analysis, chemical studies and correlation experiments with venenatine and alstovenine.     

Multiple effect of hydroxylamine on mushroom tyrosinase

Mushroom tyrosinase is affected by hydroxylamine (NH₂OH) in several ways. At relatively low concentrations (up to 33 mM) NH₂OH shortens the lag period of tyrosine hydroxylation. The o-dihydroxyphenolase activity of mushroom tyrosinase is slightly stimulated by short exposure to relatively low concentrations ofNH₂OH (1.5 mM). Relatively high concentrations ofNH₂OH (above 20 mM) inhibit the o-dihydroxyphenolase activity of the enzyme and lowers the extent of final pigment production. Preincubation of mushroom tyrosinase with different concentrations ofNH₂OH for different times results in the inactivation of the enzyme. The rate of inactivation occurred much faster under anaerobic than under aerobic conditions. It was also found that NH₂OH changes the spectra of o-quinones prepared chemically or of products formed during the oxidation of o-dihydroxyphenols by mushroom tyrosinase. These spectral changes were attributed to the formation of oximes (mono- or dioximes) as a result of an interaction between o-quinones and NH₂OH. The apparent inhibition exerted by NH₂OH on the o-dihydroxyphenolase activity of mushroom tyrosinase is, in part, due to spectral changes in pigmented product formation and, in part, due to the inactivation of the enzyme by NH₂OH.     

Tolerance to dry bubble disease (Lecanicillium fungicola) in Iranian wild germplasm of button mushroom (Agaricus bisporus)

Agaricus bisporus is the most widely cultivated mushroom. The mushroom crop is subjected to several fungal diseases. Dry bubble disease caused by Lecanicillium fungicola is among notorious diseases of A. bisporus. This study aimed to assess phenotypic resistance to dry bubble disease among A. bisporus wild strains, collected from Iran regions. The reliability of resistance evaluations regarding disease incidence and intensity was well documented. The extraordinary tolerance of some wild strains to even high degrees of inoculum concentrations (10⁷ and 10⁸ spore/m² mushroom growth bed) of the pathogen in compare to commercial cultivars approved potentials of the wild germplasm in breeding programs for resistance. Also, the potential of some Microsatellite loci for the molecular-based rapid screening of tolerance was established by attributing SSR loci of phenotypically tolerant strains to QTLs for dry-bubble resistance-related traits.     

Evaluation of Mercury Contamination in Fungi Boletus Species from Latosols,Lateritic Red Earths,and Red and Yellow Earths in the Circum-Pacific Mercuriferous Belt of Southwestern China

For the first time, highly elevated levels of mercury (Hg) have been documented for several species of the edible Fungi genus Boletus growing in latosols, lateritic red earths, and red and yellow earths from the Yunnan province of China. Analysis of Hg concentrations in the genus suggests that geogenic Hg is the dominant source of Hg in the fungi, whereas anthropogenic sources accumulate largely in the organic layer of the forest soil horizon. Among the 21 species studied from 32 locations across Yunnan and 2 places in Sichuan Province, the Hg was found at elevated level in all samples from Yunnan but not in the samples from Sichuan, which is located outside the mercuriferous belt. Particularly abundant in Hg were the caps of fruiting bodies of Boletus aereus (up to 13 mg kg^-1 dry matter), Boletus bicolor (up to 5.5 mg kg^-1 dry matter), Boletus edulis (up to 22 mg kg^-1 dry matter), Boletus luridus (up to 11 mg kg^-1 dry matter), Boletus magnificus (up to 13 mg kg^-1 dry matter), Boletus obscureumbrinus (up to 9.4 mg kg^-1 dry matter), Boletus purpureus (up to 16 mg kg^-1 dry matter), Boletus sinicus (up to 6.8 mg kg^-1 dry matter), Boletus speciosus (up to 4.9mg kg^-1 dry matter), Boletus tomentipes (up to 13 mg kg^-1 dry matter), and Boletus umbriniporus (up to 4.9 mg kg^-1 dry matter). Soil samples of the 0–10 cm topsoil layer from the widely distributed locations had mercury levels ranging between 0.034 to 3.4 mg kg^-1 dry matter. In Yunnan, both the soil parent rock and fruiting bodies of Boletus spp. were enriched in Hg, whereas the same species from Sichuan, located outside the mercuriferous belt, had low Hg concentrations, suggesting that the Hg in the Yunnan samples is mainly from geogenic sources rather than anthropogenic sources. However, the contribution of anthropogenically-derived Hg sequestered within soils of Yunnan has not been quantified, so more future research is required. Our results suggest that high rates of consumption of Boletus spp. from Yunnan can deliver relatively high doses of Hg to consumers, but that rates can differ widely because of large variability in mercury concentrations between species and locations.     

Biological Control of Olive Green Mold in Agaricus bisporus Cultivation

Successful methods to control the damaging weed mold Chaetomium olivaceum (olive green mold) in mushroom beds are not presently known. An attempt was made to control C. olivaceum by biological means. A thermophilic Bacillus sp. which showed dramatic activity against C. olivaceum on Trypticase soy agar (BBL Microbiology Systems)-0.4% yeast extract agar plates was isolated from commercial mushroom compost (phase I). When inoculated into conventional and hydroponic mushroom beds, the bacillus not only provided a significant degree of protection from C. olivaceum, but also increased yields of Agaricus bisporus.     

Discrimination training with multimodal stimuli changes activity in the mushroom body of the hawkmoth Manduca sexta

Background

The mushroom bodies of the insect brain play an important role in olfactory processing, associative learning and memory. The mushroom bodies show odor-specific spatial patterns of activity and are also influenced by visual stimuli.

Methodology/Principal Findings

Functional imaging was used to investigate changes in the in vivo responses of the mushroom body of the hawkmoth Manduca sexta during multimodal discrimination training. A visual and an odour stimulus were presented either together or individually. Initially, mushroom body activation patterns were identical to the odour stimulus and the multimodal stimulus. After training, however, the mushroom body response to the rewarded multimodal stimulus was significantly lower than the response to the unrewarded unimodal odour stimulus, indicating that the coding of the stimuli had changed as a result of training. The opposite pattern was seen when only the unimodal odour stimulus was rewarded. In this case, the mushroom body was more strongly activated by the multimodal stimuli after training. When no stimuli were rewarded, the mushroom body activity decreased for both the multimodal and unimodal odour stimuli. There was no measurable response to the unimodal visual stimulus in any of the experiments. These results can be explained using a connectionist model where the mushroom body is assumed to be excited by olfactory stimulus components, and suppressed by multimodal configurations.

Conclusions

Discrimination training with multimodal stimuli consisting of visual and odour cues leads to stimulus specific changes in the in vivo responses of the mushroom body of the hawkmoth.     

Improving biocontrol of black vine weevil (<Emphasis Type="Italic">Otiorhynchus sulcatus</Emphasis>) with entomopathogenic fungi in growing media by incorporating spent mushroom compost

Amending a peat-based growing medium with 10% v/v spent mushroom compost, a source of fungal chitin and other nutrients, prolonged the persistence of entomopathogenic fungi (Metarhizium brunneum Petsch and Beauveria bassiana (Balsamo) Vuillemin; Hypocreales: Clavicipitaceae). This resulted in improved efficacy of M. brunneum against black vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae) larvae compared with using inoculum without spent mushroom compost. B. bassiana only controlled larvae when used in combination with spent mushroom compost (75?±?7% reduction in live larvae). Mixing entomopathogenic fungal inoculum with spent mushroom compost and growing medium was as effective in controlling black vine weevil larvae as using spent mushroom compost colonised with M. brunneum or B. bassiana in the growing medium (80?±?12% reduction in live larvae). The former method is preferable since it does not require production and storage of colonised spent mushroom compost, or registration of new substrate formulations of M. brunneum or B. bassiana.     

Stimulation of yield in the cultivated mushroom by vegetable oils

Supplementation of mushroom compost at spawning and at casing with various refined and crude seed oils resulted in 1 to 1.5 lb/ft² increases in mushroom yield. Supplementation at casing with ground seeds or protein-oil combinations caused 2 to 2.5 lb/ft² increases in mushroom yield. Further evidence is presented for a relationship between lipid metabolism and the initiation of fruiting in the cultivated mushroom, Agaricus bisporus (Lange) Sing. Preliminary results suggest the possible involvement of sterols in the fruiting stimulation.     

The microbial population in the air of cultivation facility of oyster mushrooms

The microbial population in the air of mushroom cultivation facility was studied to understand the population structure and size depending on the cultivation methods and regions. The air contents of ten farmers’ oyster mushroom cultivation facilities in Kyunggi province were sampled. The results indicated that there was no difference in population size depending on the regions of mushroom cultivation. In addition, the population size of bacteria in the growth room was bigger than that of the cooling room and outside of the mushroom house, but the fungal population was similar in size between cultivation stages. With regard to population structure, Pseudomonas and Penicillium species were most frequently isolated from the air of oyster mushroom cultivation facility.     

A new circular economy approach for integrated production of tomatoes and mushrooms

Spent mushroom Substrate is the by-product generated at the end of the mushroom growing cycle. It can be used in agriculture for different purposes, including seedling production, soil conditioning or application as an organic fertilizer. Tomato is one of the world?s most important crops, requiring considerable care, in terms of both nutrition and disease control. The objective of this study was to investigate the viability of spent mushroom substrate as a nutrient source for tomato seedlings and develop an integrated tomato and mushroom co-production system. For seedling production, different compositions were evaluated with spent mushroom substrate from Pleurotus ostreatus or substrate colonized with Agaricus bisporus. The parameters evaluated comprised germination rate, seedling quality and physicochemical analysis. A tomato and mushroom integrated production system was developed using a 40-liter pot divided into upper (spent mushroom substrate and soil), middle (spent mushroom substrate from P. ostreatus) and lower (gravel) layers. For seedlings production, plants treated with the substrate colonized with A. bisporus presented a superior root length (10.1 cm) and aerial part length (6.6 cm). Co-production of tomato and mushrooms was also shown to be viable. In this co-cultivation system between tomato and mushroom, the treatment with the substrate colonized with A. bisporus differed from others, with this treatment presenting high yields of tomato (2.35 kg/plant pot) and mushrooms (1.33 kg/plant pot) within the same bucket. With this co-production system, the tomato production time was reduced by 60 days and prolonged continuous mushroom production by 120 days. These findings show a sustainable approach to manage different agroindustrial residues, encouraging the use of these residues for olericulture and fungiculture production.     

Interaction of human serum albumin with membranes containing polymer-grafted lipids: spin-label ESR studies in the mushroom and brush regimes

The adsorption of human serum albumin (HSA) to dipalmitoyl phosphatidylcholine (DPPC) bilayer membranes containing poly(ethylene glycol)-grafted dipalmitoyl phosphatidylethanolamine (PEG-DPPE) was studied as a function of content and headgroup size of the polymer lipid. In the absence of protein, conversion from the low-density mushroom regime to the high-density brush regime of polymer-lipid content is detected by the change in ESR outer hyperfine splitting, 2A_max, of chain spin-labelled phosphatidylcholine in gel-phase membranes. The values of 2A_max remain constant in the mushroom regime, but decrease on entering the brush regime. Conversion between the two regimes occurs at mole fractions X_PEG(m→b)≈0.04, 0.01-0.02 and 0.005-0.01 for PEG-DPPE with mean PEG molecular masses of 350, 2000 and 5000 Da, respectively, as expected theoretically. Adsorption of HSA to DPPC membranes is detected as a decrease of the spin label 2A_max hyperfine splitting in the gel phase. Saturation is obtained at a protein/lipid ratio of ca. 1:1 w/w. In the presence of polymer-grafted lipids, HSA adsorbs to DPPC membranes only in the mushroom regime, irrespective of polymer length. In the brush regime, the spin-label values of 2A_max are unchanged in the presence of protein. Even in the mushroom regime, protein adsorption progressively becomes strongly attenuated as a result of the steric stabilization exerted by the polymer lipid. These results are in agreement with theoretical estimates of the lateral pressure exerted by the grafted polymer in the brush and mushroom regimes, respectively.     

Influence of Ficus carica and Olea europaea leaves extracts on the mycelial growth of mushrooms in vitro

The use of 20% plant leaves extracts included fig (Ficus carica) and olive (Olea europaea) and their mixture 1:1 as an amendment in the solid agar medium (PDA) is beneficial to promote the growth of four mycelial mushrooms. These are Pleurotus ostreatus (Grey oyster mushroom), Pleurotus cornucopiae (Yellow oyster mushroom), Coriolus versicolor (Turkey Tail mushroom), and Ganoderma lucidum (Reishi mushroom). C. versicolor showed better growth reached 67?mm significantly (p?<?0.05) on OC medium after five days. While, P. cornucopiae recorded the lowest growth on FC medium reached 35.3?mm. Induction percentage of mycelial growth is changing according to the type of medium and species of fungus. In general, FOH medium exhibited the best percentage of induction was 14.89%, followed 12.48% and 9.43% by OH and OC media, while the lower percentages were 5.02% and 5.12% on FH and FC media, respectively. FC medium did not induce growth of P. cornucopiae and C. versicolor. The sterilization by Autoclave and Millipore filter showed different induction percentages. Finally, the extracts of fig and olive were useful to add in the culture media to improve the growth of mycelial mushroom in vitro.