Diversity, Dispersal and Mode of Reproduction of Amanita exitialis in Southern China.

Amanita exitialis is a poisonous mushroom and has caused many deaths in southern China. In this study, we collected 118 fruiting bodies of A. exitialis from seven different sites in Guangdong Province in southern China and investigated their genetic relationships using 14 polymorphic molecular markers. These 14 markers grouped the 118 fruiting bodies into 20 multilocus genotypes. Among these 20 genotypes, eight were each found only once while the remaining 12 were each represented by two to 54 fruiting bodies. Interestingly, among the 12 shared genotypes, four were shared between/among local populations that were separated by as far as over 80 km, a result consistent with secondary homothallic reproduction and long-distance spore dispersal. Despite the observed gene flow, significant genetic differentiations were found among the local populations, primarily due to the over-representation of certain genotypes within individual local populations. STRUCTURE analyses revealed that the 118 fruiting bodies belonged to three genetic clusters, consistent with divergence within this species in this geographic region. Interestingly, we found an excess of heterozygous individuals at both the local and the total sample level, suggesting potential inbreeding depression and heterozygous advantage in these populations of A. exitialis. We discuss the implications of our results for understanding the life cycle, dispersal, and evolution of this poisonous mushroom.

Comparative Assessment of Antifungal and Antibacterial Activities of Crude Extracts of the King Tuber Culinary-Medicinal Mushroom, Pleurotus tuber-regium (Agaricomycetes) from Cameroon.

Antifungal and antibacterial activities of crude extracts of carpophore compared with those of sclerotium of Pleurotus tuber-regium were investigated on 11 species of bacterial and 3 fungal human pathogens. The minimal inhibitory concentration (MIC) of carpophore extract was recorded to be 12.5 mg/mL on Bacillus subtilis, Enterococcus faecalis, Staphylococcus epidermidis, Escherichia cloacae, Proteus mirabilis, P. vulgaris, Klebsiella oxytoca, and K. aerogenes and 6.25 mg/mL on Staphylococcus aureus, Escherichia coli, and Mycobacterium smegmatis as well as on all three species of fungal pathogens including Candida albicans, Aspergillus fumigatus, and A. ochraceus. In comparison, the MIC of sclerotium was recorded to be 12.5 mg/mL on Bacillus subtilis and Klebsiella aerogenes; 6.25 mg/mL on Enterococcus faecalis, Staphylococcus aureus, S. epidermidis, Enterobacter cloacae, E. coli, Mycobacterium smegmatis, Proteus mirabilis, P. vulgaris, and Klebsiella oxytoca; and 3.13 mg/mL on the three fungal pathogens. Based on the abovementioned figures, it appears that strains of pathogenic fungi tested are much more sensitive to crude extracts than the abovementioned bacteria. In fact, antimicrobial activities of crude extracts of P. tuber-regium, no matter whether it is that of the carpophore or its sclerotium, are in general stronger on human pathogenic fungi than bacteria. These figures also demonstrate that crude extracts of sclerotium show a higher antimicrobial activity than that of carpophore. Carpophores and sclerotia of P. tuber-regium could therefore constitute a source of new molecules potentially more efficient than synthetic products against some human pathogenic fungi and bacteria.

Localization of the bioluminescence system in the pileus of Mycena chlorophos.

Mycena chlorophos, which is primarily distributed in Southeast Asia, is a luminous fungus that emits a bright green light from its pileus for about 2 days at approximately 20°C and high relative humidity. The distribution of bioluminescent tissues in the whole pileus and its sections was heterogeneous. The light intensity in the cap and the upper region of the gill was greater than that in the lower region of the gill. At the microscopic level, the light was predominantly emitted from the membranes of hymenium and basidia cells on the gill. The emission was both cell and region specific. The luminescence system was localized in the cell membrane, and a part of the system was on the cell membrane surface.

Biological Activities of the Polysaccharides Produced from Different Sources of Xylaria nigripes (Ascomycetes), a Chinese Medicinal Fungus.

Xylaria nigripes, a local rare medicinal fungus, has multi-antioxidant activities owing to its water extraction as shown by previous research. However, the main indicator causing the antioxidant effect was not clear, so this research focused on the antioxidant activities from different sources of X. nigripes such as fruiting body polysaccharides, mycelium intracellular polysaccharides, mycelium extracellular polysaccharides, and their deproteinization products. The mycelium intracellular polysaccharide (XnIPS-1) from X. nigripes showed the highest reducing power of antioxidant activity, since it revealed the lowest IC50 values in all the assayed methodologies. The IC50 values of chelating ferrous ion ability, ABTS radical scavenging activity, and DPPH free radical scavenging were 1412, 174.25, and 351.56 µg/mL, respectively. In addition to these results, this research also explored the mechanism between polysaccharides and antioxidants compared by FT-IR analysis. The spectrum shows that the X. nigripes polysaccharide structure changed after the proteins were removed.

Polysaccharides from extracts of Antrodia camphorata mycelia and fruiting bodies modulate inflammatory mediator expression in mice with polymicrobial sepsis.

OBJECTIVES: Antrodia camphorata (AC) is a traditional Chinese medicine, and the polysaccharides contained within AC (AC-PSs) are reported to possess various biological functions. This study extracted AC-PSs from mycelia and fruiting bodies and evaluated their influences on inflammatory mediator expressions in septic mice. METHODS: There were one normal control (NC) and three experimental groups. The normal control group underwent a sham operation, whereas the experimental groups underwent cecal ligation and puncture (CLP) to induce sepsis. Mice in the experimental groups were further divided into saline, mycelia, and fruiting body treatment groups. Saline or AC-PSs were injected intraperitoneally twice at 0.5 and 1 h after CLP and the mice were sacrificed at 6 or 16 h after sepsis for further analysis. RESULTS: Compared with the normal control group, interleukin (IL)-6, tumor necrosis factor-α, IL-10, and monocyte chemotactic protein-1 levels in plasma and/or peritoneal lavage fluid in the septic mice dramatically increased after CLP. The increased levels of these inflammatory mediators in the two AC-PS-treated groups had decreased by 16 h after CLP. Messenger RNA expressions of tumor necrosis factor-α, IL-6, and IL-10 in the splenocytes were lower in the 2 AC-PS-treated groups than in the saline group. Consistent with the results, lung nuclear factor-κB expressions decreased and less severe interstitial inflammation was observed in the histologic finding after CLP in mice that had received AC-PSs. The fruiting body group had higher white blood cell counts and lower IL-6 levels in the peritoneal lavage fluid 6 h after CLP, whereas the interferon-γ level was higher 16 h after CLP than in the saline group. These alterations were not found in mice injected with the mycelia extract. CONCLUSION: The administration of AC-PSs from mycelia or fruiting bodies decreased the inflammatory mediator expressions at the location of injury and in the circulation, especially in the late stage of sepsis. AC-PSs from fruiting bodies seemed to be more effective in decreasing the inflammatory response than those from mycelia. These findings suggest that AC-PSs from mycelia and fruiting bodies have potential protective effects against polymicrobial sepsis.

Nutritional characteristics of proteins from the volva and pileus in cultivated mushroom Dictyophora rubrovolvata.

Dictyophora rubrovolvata is one of the commercially important mushroom species in China. However, its volva and pileus account for about 65% of the whole mushroom (by fresh weight), and most of them are dumped without utilization. To effectively utilize the waste, the present study determined their proximate composition and investigated the nutritional characteristics of their proteins via the analysis of amino acid composition and protein fractionation. The results showed that the volva and pileus were rich in protein with 26.74% and 15.55% (dry basis), respectively. Predicted protein efficiency ratio values of proteins of the volva and pileus were 2.8 and 2.2, and the amino acid scores were 96 and 85.The albumin was the highest fraction both in the volva and pileus, accounting for 69.52% and 27.91% of the crude protein. The protein quality of the volva was therefore higher than that of the pileus. The volva might be developed as resource of high-quality vegetable-base protein.

Elemental composition of Physarum compressum Alb. et Schw. sporocarps and their structures cultivated on rabbit dung and agar substrates.

The elemental composition of spores, peridium walls, and lime nodes of Physarum compressum sporocarps, cultivated on rabbit dung as a natural growing environment for the slime mold and on artificial agar medium, was compared to evaluate differences that may be dependent on substrates. Whole fruiting bodies and samples of both experimental media were extracted with nitric acid or Parr digest bomb, respectively, and analyzed by means of total X-ray reflection fluorescence (TXRF). Electron probe microanalysis (EPMA) of spores, peridium walls, and lime nodes structure was carried out with the scanning electron microscope equipped with energy-dispersive spectrometer. Because of minute sizes and roughness of investigated structures, Monte Carlo simulations were utilized to establish analytical conditions of EPMA. Biological and geological standards were used in the quantification of element concentrations. According to TXRF, the fruiting bodies from agar medium revealed lower concentrations of K, Ca, Cr, Mn, and Fe in relation to fruiting bodies from the dung, reflecting elemental relationships in the experimental media. According to EPMA, the highest Ca concentration was found in the lime nodes followed by the peridium and the spores. Culturing of the slime molds on the rabbit dung indicated higher concentration of Ca in the lime nodes and peridium walls when compared with those obtained from the sporocarps grown on agar media. The opposite relation was found for the spores. The concentration of Na, Mg, P, S, and Cl was generally lower in all structures of the sporocarps harvested from the dung than from the agar medium. K was in higher concentration in analyzed structures from dung than from agar. Different element uptake (except for Ca and K) was revealed by the two methods: TXRF and EPMA.

A proteomics study of barley powdery mildew haustoria.

A number of fungal and oomycete plant pathogens of major economic importance feed on their hosts by means of haustoria, which they place inside living plant cells. The underlying mechanisms are poorly understood, partly due to difficulty in preparing haustoria. We have therefore developed a procedure for isolating haustoria from the barley powdery mildew fungus (Blumeria graminis f.sp. hordei, Bgh). We subsequently aimed to understand the molecular mechanisms of haustoria through a study of their proteome. Extracted proteins were digested using trypsin, separated by LC, and analysed by MS/MS. Searches of a custom Bgh EST sequence database and the NCBI-NR fungal protein database, using the MS/MS data, identified 204 haustoria proteins. The majority of the proteins appear to have roles in protein metabolic pathways and biological energy production. Surprisingly, pyruvate decarboxylase (PDC), involved in alcoholic fermentation and commonly abundant in fungi and plants, was absent in our Bgh proteome data set. A sequence encoding this enzyme was also absent in our EST sequence database. Significantly, BLAST searches of the recently available Bgh genome sequence data also failed to identify a sequence encoding this enzyme, strongly indicating that Bgh does not have a gene for PDC.

The structure and histochemistry of sclerotia of Ophiocordyceps sinensis.

The structure and histochemistry of sclerotia of Ophiocordyceps sinensis (synonym: Cordyceps sinensis) are described. The remains of the caterpillar epidermis and sometimes setae of the caterpillar were attached to the pigmented layer that is external to the rind of the sclerotium. The outer aerial hyphae and hyphae of the inner medulla were densely interwoven around the epidermis of the caterpillar; these eventually differentiated into the rind of the sclerotium. The medulla of the sclerotium consisted of three intergrading regions of hyphal density: high, low and a region of intermediate hyphal density. All hyphae of the medulla contained large quantities of protein, polysaccharide and polyphosphate; only the region of high hyphal density was rich in beta-1,3 glucans; the center of the sclerotium was almost devoid of hyphae and contained what are most likely the remains of caterpillar tissue. These features are compared with those of sclerotia of other fungi, and their possible significance is discussed.

Evaluation of ergosterol and its esters in the pileus, gill, and stipe tissues of agaric fungi and their relative changes in the comminuted fungal tissues.

A gradient reversed-phase high-performance liquid chromatography (HPLC) method was developed for the rapid determination of free ergosterol, ergosteryl esters, and ergocalciferol. The HPLC method was used to evaluate the distribution of ergosterol and ergosteryl esters in the different parts (stipe, pileus, and gills) of the agaric fungi, Agrocybe aegerita, Termitomyces albuminosus, and Lentinus edodes, and the relative changes of free and esterified ergosterols during the degradation of ergosterol in the comminuted fungal tissues. The results showed that total ergosterol levels and the relative abundances of free to esterified ergosterols were different among the various species and in the different parts of these agaric fungi. The results also indicated that ergosteryl esters were more stable than free ergosterol. While the content of free ergosterol markedly decreased, substantial amounts of ergosteryl esters remained for a long period, and even an increase in the contents of ergosteryl esters was also found in some comminuted fungal tissues. Therefore, it is possible that free ergosterol in the cell membrane of the dead fungal hyphae undergoes degradation or esterification, by which excess free ergosterol may be removed, and stored in cytosolic lipid particles. It is suggested that free ergosterol (not total ergosterol) should be used as a biomarker for fungal biomass.

Levels and determinants of beta(1-->3)-glucans and fungal extracellular polysaccharides in house dust of (pre-)school children in three European countries.

BACKGROUND: Mold growth is believed to be one causative factor underlying the association between dampness in buildings and increased respiratory morbidity. Measurements of beta(1-->3)-glucans and fungal extracellular polysaccharides (EPS) are used as markers of mold exposure in field studies. Little is known about their levels and determinants in homes. OBJECTIVE: To study levels and determinants of beta(1-->3)-glucan and EPS levels in mattress and living room floor dust in three European countries. METHODS: Mattress and living room floor dust was collected in the homes of 1065 German, Dutch, and Swedish (pre-)school children. All samples were analyzed for beta(1-->3)-glucans and EPS in one central laboratory. Determinants were assessed by questionnaire. RESULTS: Amounts of dust, EPS and beta(1-->3)-glucan levels differed between countries. Amounts of dust, beta(1-->3)-glucan and EPS levels for mattresses were only weakly correlated with those for living room floors. Floor dust beta(1-->3)-glucan loads, EPS loads and EPS concentrations were strongly correlated with the amount of dust sampled, which is largely determined by the type of floor that was sampled (carpeted floors had 5-20 higher amounts of dust). None of the other determinants was consistently and statistically significantly associated with amounts of dust, beta(1-->3)-glucan and EPS concentrations on floors and mattresses. CONCLUSION: Mattress dust and floor dust are two different measures of exposure to the investigated mold components. Living room floor beta(1-->3)-glucan and EPS loads and EPS concentrations are largely determined by the type of floor sampled. Differences between countries can only partly be explained by the determinants studied.

[Analysis of the main amatoxins and phallotoxins in Amanita exitialis--a new species in China].

The content and distribution of the main Amatoxins (alpha-amanitin, beta-amanitin) and Phallotoxins (Phallacidin, Phallisin, Phalloin, Phalloidin) in the three tissues (cap, stipe and volva) of Amanita exitialis were evaluated by means of high-performance liquid chromatography. The results showed that Amanita exitialis was a lethal mushrooms, the cap had the highest content of total toxins, it reached 8152.6 microg/g dry weight, the toxins content in stipe reached 3742.3 microg/g dry weight, whereas the volva had the lowest content of total toxins,it had only 1142.5 microg/g dry weight. The distribution of Amatoxins and Phallotoxins in the tissues were revealed and it displayed that the content of Amatoxins (alpha-amanitin and beta-amanitins especially alpha-amanitin) in the cap, stipe or volva of A. exitialis was higher than that of Phallotoxins (Phallacidin, Phallisin, Phalloidin and Phalloin). But the content of Phallotoxins especially Phallacidin was gradationally higher from cap to stipe and to volva.

Activation of the alternative complement pathway by Agaricus blazei Murill.

Components of Agaricus blazei Murill have been demonstrated to have a wide range of immunopotentiating activities. The present study was designed to evaluate the effect of A. blazei Murill upon activation of the complement system in human serum in vitro. Additional studies were performed to determine the cytotoxic effect of complement-opsonized particles of A. blazei Murill against human tumor cells in culture. A fine particle of A. blazei Murill (ABP), prepared by mechanical disruption, was used throughout the experiments. ABP activated the human complement system via the alternative pathway in human serum. Activation of the alternative pathway was both time- and dose-dependent. When the particles from fruiting bodies of A. blazei Murill (ABP-F) were reacted with human serum, the formation of complement-opsonized ABP, iC3b-ABP-F complexes, and binding of the complexes to human peripheral blood monocytes, were demonstrated in vitro by immunofluorescence. Further, the resident human peripheral nucleated cells incubated in the presence of iC3b-ABP-F complexes inhibited the proliferation of human tumor cell line TPC-1 in vitro.

[Changes in the composition of dendrochines in the cultivation dynamics of Dendrodochium toxicum 100115]. / Izmenenie komponentnogo sostava dendrodokhinov v dinamike kul'tivirovaniia Dendrodochium toxicum 100115.

The dynamics of change in the component composition of dendrodochines in the process of cultivation of Dendrodochium toxicum 100115 has been studied. It has been shown on the basis of the data of thin-layer chromatography that verrucarines A and J are found during the whole period of the fungus growth. Rhoridines A and E in the initial period of cultivation (1-2 days) are found in trace quantities only. Rhoridine A is found on the 1-3 and 8-10th days of the producer cultivation and its content is inconsiderable only on the 4-6th day. An analysis of qualitative content of the studied verrucarines and rhoridines evidence for its considerable changes in the dynamics of the fungus growth and supposes the reci procal transformation of certain components. The registered processes are accompanied by the change of biological activity of preparations with respect to the used test-objects. A possible mechanism of the producer resistance to its own toxical metabolites is discussed in the light of the data obtained.