Fungal strain matters: colony growth and bioactivity of the European medicinal polypores Fomes fomentarius, Fomitopsis pinicola and Piptoporus betulinus

Tailoring the Mechanical Properties of Fungal Mycelium Mats with Material Extrusion Additive Manufacturing of PHBH and PLA Biopolymers

To advance the concept of a circular economy, fungal mycelium-based materials are drawing increased attention as substitutes for nonsustainable materials, such as petroleum-based and animal-derived products, due to their biodegradability, low carbon footprint, and cruelty-free nature. Addressing the challenge of mechanical properties in fungal mycelium products, this study presents a straightforward approach for reinforcing fungal mycelium mats. This is achieved by using two bio-based and biodegradable polymers, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) and polylactic acid (PLA), via material extrusion additive manufacturing (MEX AM), commonly known as 3D printing, to produce fungal mycelium-biopolymer composites. By analyzing the mechanical properties, roughness, and morphology, this study demonstrates significant improvements in ultimate tensile strength with the application of PHBH and even more with PLA, while elasticity is reduced. The study also discusses potential improvements to enhance the quality of the fungal mycelium-biopolymer composites without trading off bio-based and biodegradable features, offering a promising pathway for the development of more durable and sustainable fungal mycelium products.

Fungal Strain Influences Thermal Conductivity, Hydrophobicity, Color Homogeneity, and Mold Contamination of Mycelial Composites

Mycomaterials are biomaterials made by inoculating a lignocellulosic substrate with a fungus, where the mycelium acts as a binder and enhances material properties. These materials are well suited as sustainable alternatives to conventional insulation materials thanks to their good insulation properties, low density, degradability, and fire resistance. However, they suffer from mold contamination in moist environments and poor perception ("organic" appearance). Furthermore, most mycomaterials to date have been derived from a limited range of fungal species, leaving the vast phenotypic diversity of fungi largely untapped. We hypothesized that by exploring a broader range of strains, we could enhance the likelihood of discovering a material that meets the needs for insulation panels. We generated mycomaterials from nine fungal strains and measured their thermal conductivity, mold resistance, and perception properties. We observed significant variations across strains on these three parameters. Thermal conductivity ranged from levels comparable to extruded polystyrene to nearly as effective as polyurethane (0.039 to 0.019 W/mK). All materials generated were hydrophobic (equivalent to 105-122° contact angle), but differed by a factor of two in color appearance and sensitivity to mold (0-94% of surface colonized). We also found a method to improve resistance to mold using deactivated contaminant propagules.

Enhancement of antioxidant activity and total phenolic content of Fomitopsis pinicola mycelium extract

BACKGROUND

Fomitopsis pinicola is one of the most common fungi found in temperate zone of Europe, widely distributed spread in Asia and North America. Fungus has a wide range of therapeutic activity: antitumor, antimicrobial, anti-inflammatory, antidiabetic, antifungal, hepatoprotective, hemostatic action. A number of studies have confirmed the significant antioxidant activity of F. pinicola fruiting bodies. However, the controlled cultivation conditions that influence fungal growth and metabolite production of F. pinicola, particularly the mycelial growth and biosynthesis of metabolites in its culture broth, as well as the antioxidant activity of its mycelium, remain poorly understood.

RESULTS

This study investigated the impact of cultivation conditions on F. pinicola mycelium growth, phenols synthesis and antioxidant activity. Difference in the biosynthetic activity of F. pinicola under tested cultivation conditions was established. A highest value of 2,2-diphenyl-1-picryl-hydrazyl (DPPH•) inhibition (78.2 ± 0.9%) was found for a mycelium cultivated at 30 ºC, while cultivation at a lower temperature (20 ºC) was suitable for biomass growth (8.5 ± 0.3 g/L) and total phenolic content (TPC) 11.0 ± 0.6 mg GAE/g. Carbon and nitrogen sources in a cultivation broth significantly influenced the studied characteristics. Xylose supported the highest DPPH• inhibition (89.91 ± 0.5%) and TPC (16.55 ± 0.4 mg GAE/g), while galactose yielded the best biomass (4.0 ± 0.3 g/L). Peptone was the most effective nitrogen source for obtaining the mycelium with high potential of DPPH• radical inactivation (90.42 ± 0.5%) and TPC (17.41 ± 0.5 mg GAE/g), while the maximum biomass yield (7.8 ± 0.6 g/L) was found with yeast extract in cultivation medium. F. pinicola demonstrated the ability to grow and produce bioactive metabolites across a wide pH range from 2.5 to 7.5. Shaking cultivation resulted in the highest TPC (21.44 ± 0.10 mg GAE/g), though the same level of antioxidant activity (93%) was achieved under both shaking and static cultivation on the 7th and 28th days, respectively.

CONCLUSION

Controlling cultivation parameters makes it possible to regulate the metabolic and biochemical processes of F. pinicola, facilitating the balance needed to obtain optimal biomass, phenols and antioxidant activity. The findings show the potential to increase phenol production by 2.25 and 2.23 times under shaking and static conditions, respectively, while maintaining a high level of activity.

Characterising the Metabolomic Diversity and Biological Potentials of Extracts from Different Parts of Two Cistus Species Using UHPLC-MS/MS and In Vitro Techniques

This study investigates the biochemical composition and biological properties of different parts (leaves, roots, and twigs) of two Cistus species (Cistus monspeliasis and Cistus parviflorus). The extracts were analysed using UHPLC-MS/MS to determine their chemical profiling. A range of antioxidant assays were performed to evaluate the extract's antioxidant capabilities. The enzyme inhibition studies focused on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase, and α-glucosidase and tyrosinase. In addition, the study examined the antimicrobial effects on different bacteria and yeasts and evaluated the toxicity using the MTT assay. Quinic acid, citric acid, gallic acid, catechin, quercetin derivatives, kaempferol, myricetin, ellagic acid, prodelphinidins, procyanidins, scopoletin, and flavogallonic acid dilactone are the main bioactive compounds found in both species. In enzyme inhibition assays, C. monspeliasis roots exhibited significant activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), with the values of 2.58 ± 0.02 mg GALAE/g and 11.37 ± 1.93 mg GALAE/g, respectively. Cytotoxicity studies showed mostly weak toxicity, with some samples moderately reducing viability in RAW and HepG2 cells. These findings underscore the diverse biochemical profiles and bioactive potential of Cistus species, suggesting their utility as natural sources of antioxidants and enzyme inhibitors for pharmaceutical and nutraceutical development.

Anti-ultraviolet, antibacterial, and biofilm eradication activities against Cutibacterium acnes of melanins and melanin derivatives from Daedaleopsis tricolor and Fomes fomentarius

Fomes fomentarius and Daedaleopsis tricolor produced significant amounts of water-insoluble melanins, and our previous study successfully enhanced their water solubility by arginine modification. This research aimed to investigate the anti-ultraviolet, antibacterial, and biofilm eradication activities of both the melanins and arginine-modified melanin (melanin derivatives) from these two fungi against an acne-causing bacterium (Cutibacterium acnes). Apart from these, the cytotoxicity of the melanins and melanin derivatives on human skin cells was also evaluated. Melanin derivatives of both two fungi showed significantly higher antibacterial and biofilm eradication activities compared with their original forms. Specifically, the MIC50 values of the melanin derivatives (1,000 μg/mL) are the same as those of erythromycin. Regarding biofilm eradication capacity, the MBEC50 value of D. tricolor melanin derivative (250 μg/mL) was just half of both erythromycin and F. fomentarius melanin derivative. However, it required a 2-fold higher concentration of melanin derivatives than erythromycin to inhibit 90% of the bacterial population and eradicate 90% of their biofilm. Regarding anti-ultraviolet activity, blending melanins or melanin derivatives with a moisturizer/sunscreen enhanced their UV light absorption and the sun protection factor (SPF) values. In addition, melanins showed better effects than their derivatives, and those of D. tricolor were better than F. fomentarius. Remarkably, adding D. tricolor melanin (10%) to a Nivea pure cream could turn this cream into a broad-spectrum sunscreen, with its SPF value and critical wavelength increasing from 7.74 and 338.67 to 14.02 and 377.0, respectively. In addition, adding melanin or a melanin derivative of D. tricolor to an Olay sunscreen enhanced the SPF and the critical wavelength of the sunscreen from 17.25 and 371.67 to 23.82 and 374 and 23.38 and 372, respectively. Notably, melanins and melanin derivatives showed no toxicity in human fibroblasts. The obtained data suggest that arginine modification significantly enhanced the antibacterial and biofilm eradication activities of melanins from D. tricolor and F. fomentarius. However, this is not the case when it comes to their anti-ultraviolet activities. In addition, melanin and melanin derivatives from D. tricolor are potential candidates for anti-acne sunscreen products and are worth further investigation.

Antiproliferative and Antibacterial Activity of Polyporoid Fungi from Veracruz, Mexico

Polyporoid fungi represent a vast source of bioactive compounds with potential pharmacological applications. The importance of polyporoid fungi in traditional Chinese medicine has led to an extensive use of some species of Ganoderma for promoting health and longevity because their consumption is associated with several bioactivities. Nevertheless, bioactivity of some other members of the Polyporaceae family has also been reported. This work reports the antiproliferative and antibacterial activity of crude extracts obtained from fruiting bodies of polypore fungi collected from the central region of Veracruz, Mexico, aimed at understanding the diversity of polypore species with potential pharmacological applications. 29 collections were identified macro- and microscopically in 19 species of polyporoid fungi, belonging to 13 genera. The antiproliferative activity screening of extracts against solid tumor cell lines (A549, SW1573, HeLa, HBL-100, T-47D, WiDr) allow us to identify four extracts with strong bioactivity [half-maximal growth inhibition (GI50) ≤ 50 μg/mL]. After this, a phylogenetic analysis of DNA sequences from the ITS region obtained from bioactive specimens allowed us to identify three extracts as Pycnoporus sanguineus (GI50 = ≤ 10 μg/mL) and the fourth bioactive extract as Ganoderma oerstedii (GI50 = < 50 μg/mL. Likewise, extracts from P. sanguineus showed mild or moderate antibacterial activity against Escherichia coli, Staphylococcus aureus and Xanthomonas albilineas. Bioprospecting studies of polyporoid fungi add to the knowledge of the diversity of macrofungi in Mexico and allow us to select one of the bioactive P. sanguineus to continue the pursuit of bioactive compounds through mycochemical studies.

Antimicrobial Activity of Different Collections of Medicinal Polypore Fungus Fomitopsis pinicola (Agaricomycetes)

The study of antimicrobial activity (AMA) of 14 genetically identified dikaryotic strains of red belted medicinal polypore Fomitopsis pinicola isolated from Betula sp. and other deciduous trees, as well as conifers Picea sp. and Abies alba in Russia, France and Italy against test fungi and bacteria is discussed. The results of this study have shown that F. pinicola strains possess significant antimicrobial potential against dermatophytes (Chrysosporium keratinophilum, Microsporum gypseum, Trichophyton terrestre) and Penicillium species (P. griseofulvum, P. sp.) isolated from soil samples in Armenia, as well as Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium) and Gram-positive (Staphylococcus aureus) bacteria received from different culture collections. In dual culture experiments, F. pinicola showed high antagonistic/antifungal activity toward test fungi by suppressing their average growth rate (GRavr) and sporulation causing morphological changes of colonies. The cultural broth (CB) samples obtained from 21-d static culture of F. pinicola demonstrated higher antifungal activity (AFA) with fungicidic (FC) and fungistatic (FS) effects against dermatophytes and more than 50% GRavr inhibitory effect for Penicillium spp. compared with mycelial extracts (ME) samples. Tested CB and ME samples of F. pinicola showed also antibacterial activity (ABA) against test bacteria. The AMA of CB samples was higher than the activity of ME samples. The mycelium of F. pinicola may be considered a potential source of extra- and intracellular antimicrobial compounds. Further studies to elucidate the mechanism of antimicrobial effect of F. pinicola for developing mushroom-derived biotech products are warranted.

Growth, morphology, and formation of cinnabarin in Pycnoporus cinnabarinus in relation to different irradiation spectra

BACKGROUND

The demand for natural pigments in general, and for fungi-derived pigments in particular, is constantly rising. Wood-decomposing fungi represent a promising source for natural pigments and they are usually easy to cultivate in pure culture. One of them, i.e., Pycnoporus cinnabarinus, offers a highly interesting spectrum of bioactivity, partly due to the formation of the orange-red pigment cinnabarin. However, apart from a few studies addressing its diverse potential biotechnological applications, there is still a large gap of knowledge concerning the influence of light on the formation of cinnabarin. The aim of this work was to investigate the effect of different irradiations on the cinnabarin content, the growth, and the morphology of three different P. cinnabarinus strains. We used highly standardized irradiation conditions and cultivation techniques in combination with newly developed methods for the extraction and direct quantification of cinnabarin.

RESULTS

Red, green, blue, and UV-A irradiation (mean irradiance Ee = 1.5 ± 0.18 W m-2) had considerable effects on the growth and colony appearance of all three P. cinnabarinus strains tested. The cinnabarin content determined was, thus, dependent on the irradiation wavelength applied, allowing strain-specific thresholds to be defined. Irradiation with wavelengths below this strain-specific threshold corresponded to a lower cinnabarin content, at least at the intensity applied. The orange-red pigment appeared by light microscopy as incrusted extracellular plaques present on the hyphal walls. Highly efficient vegetative propagation occurred by arthroconidia, and we observed the tendency that this asexual reproduction was (i) most frequent in the dark but (ii) never occurred under UV-A exposure.

CONCLUSION

 This study highlights a differential photo-dependence of growth, morphology, and cinnabarin formation in P. cinnabarinus. This confirms that it is advisable to consider the wavelength of the light used in future biotechnological productions of natural pigments.

Appraisals on the chemical characterization and biological potentials of Ranunculus constantinopolitanus extracts using chromatographic, computational, and molecular network approaches

In this context, phytochemicals were extracted from Ranunculus constantinopolitanus using ethyl acetate (EA), ethanol, ethanol/water (70%), and water solvent. The analysis encompassed quantification of total phenolic and flavonoid content using spectrophotometric assays, chemical profiling via high performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) for the extracts, and assessment of antioxidant activity via 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), Cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), metal chelating (MCA), and phosphomolybdenum (PBD) assays. Moreover, antimicrobial activity was assessed against four different bacterial strains, as well as various yeasts. Enzyme inhibitory activities were evaluated against five types of enzymes. Additionally, the extracts were examined for their anticancer and protective effects on several cancer cell lines and the human normal cell line. All of the extracts exhibited significant levels of ferulic acid, kaempferol, and caffeic acid. All tested extracts demonstrated antimicrobial activity, with Escherichia coli and Pseudomonas aeruginosa being most sensitive to EA and ethanol extracts. Molecular docking studies revealed that kaempferol-3-O-glucoside strong interactions with AChE, BChE and tyrosinase. In addition, network pharmacology showed an association between gastric cancer and kaempferol-3-O-glucoside. Based on the results, R. constantinopolitanus can be a potential reservoir of bioactive compounds for future bioproduct innovation and pharmaceutical industries.

Antifungal Activity of Medicinal Mushrooms and Optimization of Submerged Culture Conditions for Schizophyllum commune (Agaricomycetes)

The main goal of the present study was the exploration of the antifungal properties of Agaricomycetes mushrooms. Among twenty-three tested mushrooms against A. niger, B. cinerea, F. oxysporum, and G. bidwellii, Schizophyllum commune demonstrated highest inhibition rates and showed 35.7%, 6.5%, 50.4%, and 66.0% of growth inhibition, respectively. To reveal culture conditions enhancing the antifungal potential of Sch. commune, several carbon (lignocellulosic substrates among them) and nitrogen sources and their optimal concentrations were investigated. Presence of 6% mandarin juice production waste (MJPW) and 6% of peptone in nutrient medium promoted antifungal activity of selected mushroom. It was determined that, extracts obtained in the presence of MJPW effectively inhibited the grow of pathogenic fungi. Moreover, the content of phenolic compounds in the extracts obtained from Sch. commune grown on MJPW was several times higher (0.87 ± 0.05 GAE/g to 2.38 ± 0.08 GAE/g) than the extracts obtained from the mushroom grown on the synthetic (glycerol contained) nutrient medium (0.21 ± 0.03 GAE/g to 0.88 ± 0.05 GAE/g). Flavonoid contents in the extracts from Sch. commune varied from 0.58 ± 0.03 to 27.2 ± 0.8 mg QE/g. Identification of phenolic compounds composition in water and ethanol extracts were provided by mass spectrometry analysis. Extracts demonstrate considerable free radical scavenging activities and the IC50 values were generally low for the extracts, ranging from 1.9 mg/ml to 6.7 mg/ml. All the samples displayed a positive correlation between their concentration (0.05-15.0 mg/ml) and DPPH radical scavenging activity. This investigation revealed that Sch. commune mushroom has great potential to be used as a source of antifungal and antioxidant substances.

Pilot-Scale Production of the Natural Colorant Laetiporic Acid, Its Stability and Potential Applications

Laetiporus sulphureus, a wood-decaying basidiomycete, produces yellow-orange pigments in fruiting bodies and, as was recently shown, in submerged cultivated mycelia. Out of four strains, the most potent laetiporic acid producer was identified and its yield compared in different media. The complex Moser b medium was replaced by potato dextrose broth, achieving higher yields at a lower cost. Cultivation was then scaled up from shake flask to a 7 L stirred tank bioreactor. Optimization of parameters led to increased product concentrations up to 1 g L−1, the highest yield reported so far. An in situ product recovery strategy with a biphasic system was established, increasing the yield by 19% on the shake flask scale. A crude ethanolic extract of the biomass was examined for color stability and application trials. In contrast to what has been suggested in the past, the pigment showed limited long-term stability to oxygen and light, but was stable under storage in the dark at 4 °C under nitrogen. The orange extract was successfully incorporated into different matrices like foods, cosmetics and textiles. Laetiporic acid can potentially replace petrochemical based synthetic dyes, and can thus support the development of a circular bioeconomy.

Use of Secondary Metabolites of Wood-Decaying Fungi to Reduce Damping off Disease

Phytopathogenic fungi can cause plant diseases that are difficult to control, including mass mortality of some tree species. The Fusarium oxysporum complex (sensu lato) is one of the most dangerous groups of phytopathogenic fungi, causing the death of conifer species, including Pinus sylvestris seedlings in forest and ornamental nurseries. Recently, non-chemical methods of plant protection have become the basis of integrated pest management (IPM) in the European Union (EC Directive). The possibility of protection of pine seedlings against the pathogen F. oxysporum using active substances from wood-destroying fungi commonly found in forests was examined. Methanolic extracts of Fomitopsis pinicola, Ganoderma applanatum, and Trametes versicolor were found to contain substances effective in both prevention and treatment of infected seedlings. G. applanatum and T. versicolor showed particular biological activity in increasing plant resistance. Efficacy, especially of the extract of F. pinicola, increased with concentration. Further field trials are needed to confirm the results obtained in laboratory tests on plant protection.

The photosensitizer emodin is concentrated in the gills of the fungus Cortinarius rubrophyllus

The colorful agaricoid fruiting bodies of dermocyboid Cortinarii owe their magnificent hue to a mixture of anthraquinone (AQ) pigments. Recently, it was discovered that some of these fungal anthraquinones have an impressive photopharmacological effect. The question, therefore, arises as to whether these pigments are also of ecological or functional significance. According to the optimal defense hypothesis, toxic molecules should be enriched in spore-producing structures, such as the gills of agarics. To test this hypothesis, we studied the distribution of fungal AQs in the fruiting body of Cortinarius rubrophyllus. The fungus belongs to the well-studied Cortinarius subgenus Dermocybe but has not been chemically characterized. Here, we report on the pigment profile of this beautiful fungus and focus on the distribution of anthraquinone pigments in the fruiting body for the first time. Here it is statistically confirmed that the potent photosensitizer emodin is significantly enriched in the gills. Furthermore, we show that the extract is photoactive against cancer cells and bacteria.

Establishment of the basidiomycete Fomes fomentarius for the production of composite materials

Background

Filamentous fungi of the phylum Basidiomycota are considered as an attractive source for the biotechnological production of composite materials. The ability of many basidiomycetes to accept residual lignocellulosic plant biomass from agriculture and forestry such as straw, shives and sawdust as substrates and to bind and glue together these otherwise loose but reinforcing substrate particles into their mycelial network, makes them ideal candidates to produce biological composites to replace petroleum-based synthetic plastics and foams in the near future.

Results

Here, we describe for the first time the application potential of the tinder fungus Fomes fomentarius for lab-scale production of mycelium composites. We used fine, medium and coarse particle fractions of hemp shives and rapeseed straw to produce a set of diverse composite materials and show that the mechanical materials properties are dependent on the nature and particle size of the substrates. Compression tests and scanning electron microscopy were used to characterize composite material properties and to model their compression behaviour by numerical simulations. Their properties were compared amongst each other and with the benchmark expanded polystyrene (EPS), a petroleum-based foam used for thermal isolation in the construction industry. Our analyses uncovered that EPS shows an elastic modulus of 2.37 ± 0.17 MPa which is 4-times higher compared to the F. fomentarius composite materials whereas the compressive strength of 0.09 ± 0.003 MPa is in the range of the fungal composite material. However, when comparing the ability to take up compressive forces at higher strain values, the fungal composites performed better than EPS. Hemp-shive based composites were able to resist a compressive force of 0.2 MPa at 50% compression, rapeseed composites 0.3 MPa but EPS only 0.15 MPa.

Conclusion

The data obtained in this study suggest that F. fomentarius constitutes a promising cell factory for the future production of fungal composite materials with similar mechanical behaviour as synthetic foams such as EPS. Future work will focus on designing materials characteristics through optimizing substrate properties, cultivation conditions and by modulating growth and cell wall composition of F. fomentarius, i.e. factors that contribute on the meso- and microscale level to the composite behaviour.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40694-022-00133-y.

Collection and Characterization of Wood Decay Fungal Strains for Developing Pure Mycelium Mats

Wood decay fungi (WDF) seem to be particularly suitable for developing myco-materials due to their mycelial texture, ease of cultivation, and lack of sporification. This study focused on a collection of WDF strains that were later used to develop mycelium mats of leather-like materials. Twenty-one WDF strains were chosen based on the color, homogeneity, and consistency of the mycelia. The growth rate of each strain was measured. To improve the consistency and thickness of the mats, an exclusive method (newly patented) was developed. The obtained materials and the corresponding pure mycelia grown in liquid culture were analyzed by both thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) to evaluate the principal components and texture. TGA provided a semi-quantitative indication on the mycelia and mat composition, but it was hardly able to discriminate differences in the production process (liquid culture versus patented method). SEM provided keen insight on the mycelial microstructure as well as that of the mat without considering the composition; however, it was able to determine the hyphae and porosity dimensions. Although not exhaustive, TGA and SEM are complementary methods that can be used to characterize fungal strains based on their desirable features for various applications in bio-based materials. Taking all of the results into account, the Fomitopsis iberica strain seems to be the most suitable for the development of leather-like materials.

A New High-Throughput-Screening-Assay for Photoantimicrobials Based on EUCAST Revealed Unknown Photoantimicrobials in Cortinariaceae

Antimicrobial resistance is one of the biggest health and subsequent economic threat humanity faces. Next to massive global awareness campaigns, governments and NGOs alike stress the need for new innovative strategies to treat microbial infections. One of such innovative strategies is the photodynamic antimicrobial chemotherapy (PACT) in which the synergistic effects of photons and drugs are exploited. While many promising reports are available, PACT - and especially the drug-design part behind - is still in its infancy. Common best-practice rules, such as the EUCAST or CLSI protocols for classic antibiotics as well as high-throughput screenings, are missing, and this, in turn, hampers the identification of hit structures. Hit-like structures might come from synthetic approaches or from natural sources. They are identified via activity-guided synthesis or isolation strategies. As source for new antimicrobials, fungi are highly ranked. They share the same ecological niche with many other microbes and consequently established chemical strategies to combat with the others. Recently, in members of the Cortinariaceae, especially of the subgenus Dermocybe, photoactive metabolites were detected. To study their putative photoantimicrobial effect, a photoantimicrobial high-throughput screening (HTS) based on The European Committee on Antimicrobial Susceptibility Testing (EUCAST) was established. After validation, the established HTS was used to evaluate a sample set containing six colorful representatives from the genus Cortinarius (i.e., Cortinarius callisteus, C. rufo-olivaceus, C. traganus, C. trivialis, C. venetus, and C. xanthophyllus). The assay is built on a uniform, light-emitting diode (LED)-based light irradiation across a 96-well microtiter plate, which was achieved by a pioneering arrangement of the LEDs. The validation of the assay was accomplished with well-known photoactive drugs, so-called photosensitizers, utilizing six distinct emission wavelengths (λexc = 428, 478, 523, 598, or 640 nm) and three microbial strains (Candida albicans, Staphylococcus aureus, and Escherichia coli). Evaluating the extracts of six Cortinarius species revealed two highly promising species, i.e., C. rufo-olivaceus and C. xanthophyllus. Extracts from the latter were photoactive against the Gram-positive S. aureus (c = 7.5 μg/ml, H = 30 J/cm2, λ = 478 nm) and the fungus C. albicans (c = 75 μg/ml, H = 30 J/cm2, λ = 478 nm).

Functional expression and characterization of two laccases from the brown rot Fomitopsis pinicola

Laccase is predominantly found in lignin degrading filamentous white rot fungi, where it is involved in the oxidative degradation of this recalcitrant heteropolymer. In brown rot fungi it is much less prevalent: laccases from only a few brown rots have been detected and only two have been characterized. This study tries to understand the role of this ligninolytic enzyme in brown rots by investigating the catalytic properties of laccases secreted by Fomitopsis pinicola FP58527 SS1. When grown on either poplar or spruce wood blocks, several laccases were detected in the secretome. Two of them (FpLcc1 and FpLcc2) were heterologously produced using Trichoderma reesei QM9414 Δxyr1 as expression host and purified to homogeneity by consecutive steps of hydrophobic interaction, anion exchange and size exclusion chromatography. With the substrates 2,2-azino-bis(3-ethylthiazoline-6-sulfonate) (ABTS), 2,6-dimethoxyphenol (2,6-DMP) and guaiacol both laccases showed similar, low pH-optima below 3 for ABTS and 2,6-DMP and at pH 3.5 for guaiacol which is at the acidic end of laccases isolated from white rot fungi. The determined K_M values were low while k_cat values measured at acidic conditions were comparable to those reported for other laccases from white rot fungi. While both enzymes showed a moderate decrease in activity in the presence of oxalic and citric acid FpLcc2 was activated by acetic acid up to 3.7 times. This activation effect is much more pronounced at pH 5.0 compared to pH 3.0 and could already be observed at a concentration of 1 mM acetic acid.

Unleashing the Biological Potential of Fomes fomentarius via Dry and Wet Milling

Fomes fomentarius, usually referred to as tinder conk, is a common wood-based fungus rich in many interesting phytochemicals and with an unique porous structure. Dry or wet ball milling of this sponge on a planetary mill results in small particles with sizes in the range of 10 µm or below. Suspended in water and without preservatives or other stabilizers, the resulting micro-suspensions are sterile for around six days, probably due to the increased temperatures of around 80 °C especially during the wet milling process. The suspensions also exhibit excellent antioxidant activities as determined in the DPPH, ferric reducing antioxidant potential (FRAP) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. In the DPPH assay, IC₅₀ values of 0.02–0.04% w/v and 0.04% w/v were observed for dry and wet milled samples, respectively. In the FRAP assay, IC₅₀ values of <0.02% w/v and 0.04% w/v were observed for dry and wet milled samples, respectively. In contrast, the ABTS assay provided IC₅₀ values of 0.04% w/v and 0.005% w/v, respectively. Notably, this activity is mostly—albeit not exclusively—associated with the highly porous particles and their large surfaces, although some active ingredients also diffuse into the surrounding aqueous medium. Such suspensions of natural particles carrying otherwise insoluble antioxidants on their surfaces provide an interesting avenue to unleash the antioxidant potential of materials such as sponges and barks. As dry milling also enables longer storage and transport, applications in the fields of medicine, nutrition, agriculture, materials and cosmetics are feasible.

Identification of Feldin, an Antifungal Polyyne from the Beefsteak Fungus Fistulina hepatica

Fruiting body-forming members of the Basidiomycota maintain their ecological fitness against various antagonists like ascomycetous mycoparasites. To achieve that, they produce myriads of bioactive compounds, some of which are now being used as agrochemicals or pharmaceutical lead structures. Here, we screened ethyl acetate crude extracts from cultures of thirty-five mushroom species for antifungal bioactivity, for their effect on the ascomycete Saccharomyces cerevisiae and the basidiomycete Ustilago maydis. One extract that inhibited the growth of S. cerevisiae much stronger than that of U. maydis was further analyzed. For bioactive compound identification, we performed bioactivity-guided HPLC/MS fractionation. Fractions showing inhibition against S. cerevisiae but reduced activity against U. maydis were further analyzed. NMR-based structure elucidation from one such fraction revealed the polyyne we named feldin, which displays prominent antifungal bioactivity. Future studies with additional mushroom-derived eukaryotic toxic compounds or antifungals will show whether U. maydis could be used as a suitable host to shortcut an otherwise laborious production of such mushroom compounds, as could recently be shown for heterologous sesquiterpene production in U. maydis.

Antimicrobial and Cytotoxic Activity of Silver Nanoparticles Stabilized by Natural Biopolymer Arabinogalactan

Silver nanoparticles were synthesized by chemical reduction of silver nitrate using arabinogalactan polysaccharide as a reducing agent and a stabilizer. The average size of nanoparticles, obtained by analyzing TEM-images, was 10.8[Formula: see text]nm; zeta potential [Formula: see text][Formula: see text]mV. A study of the sol by electron diffraction showed that silver in the sample is in metallic form. The resulting preparation of silver nanoparticles showed both antibacterial and antifungal activity. A pronounced antibacterial activity of silver nanoparticles was demonstrated both in relation to conditionally pathogenic gram-positive (Bacillus subtilis and B. coagulans) and gram-negative (Escherichia coli) bacteria. Silver nanoparticles also possess antifungal activity against macromycete Fomitopsis sp., as well as two strains of micromycetes Trichoderma citrinoviride and Fusarium sporotrichioides. Using the methods of light and fluorescence microscopy, MTT-analysis and Real-time cell analysis, the cytotoxic activity of silver nanoparticles was investigated on HepG2 human hepatocellular carcinoma cells. It was demonstrated that nanoparticles cause a suppression of cell metabolic and proliferative activity, as well as dose-dependent induction of cell death (average relative EC[Formula: see text] value was [Formula: see text]g/ml). The preparation of silver nanoparticles stabilized by arabinogalactan can be used in medicine, as a potential antimicrobial and antitumor agent.

A Wild Fomes fomentarius for Biomediation of One Pot Synthesis of Titanium Oxide and Silver Nanoparticles for Antibacterial and Anticancer Application

The present study offers an alternative method for green synthesis of the formation of two types of nanoparticles (NPs). These NPs, titanium oxide and silver NPs (TiO₂ and Ag NPs, respectively), were obtained from the amalgamation of intracellular extract of a wild mushroom, Fomes fomentarius, with aqueous solutions of titanium isopropoxide and silver nitrate, respectively. F. fomentarius was identified phenotypically and by 18S ribosomal RNA gene sequencing (Gene accession no: MK635351). The biosynthesis of TiO₂ and Ag NPs was studied and characterized by X-ray diffraction (XRD), diffuse reflectance UV-Visible spectroscopy (DR-UV), fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and transmission electron microscope (TEM). Success was achieved in obtaining NPs of differing sizes and shapes. The antibacterial and anticancer activity of the NPs was significant with morphological damage being caused by both, although Ag NPs (10–20 nm) were found to have profound effects on bacterial and cancer cells in comparison to TiO₂ NPs (100–120 nm). These metal NPs, synthesized using wild mushrooms, hold a great potential in biomedicinedue to an effective enzyme combination, which permits them to modify different chemical compounds to less toxic forms, which is required for ecofriendly and safe biomaterials.

Aspects Determining the Dominance of Fomitopsis pinicola in the Colonization of Deadwood and the Role of the Pathogenicity Factor Oxalate

Carbon and mineral cycling in sustainable forest systems depends on a microbiome of basidiomycetes, ascomycetes, litter-degrading saprobes, ectomycorrhizal, and mycoparasitic fungi that constitute a deadwood degrading consortium. The brown rot basidiomycete Fomitopsis pinicola (Swartz: Fr.) P. Karsten (Fp), as an oxalate-producing facultative pathogen, is an early colonizer of wounded trees and fresh deadwood. It replaces basidiomycetous white rot fungi and non-basidiomycetous fungal phyla in the presence of its volatilome, but poorly in its absence. With the goal of determining its dominance over the most competitive basidiomycetes and its role in fungal successions within the forest microbiome in general, Fp was exposed to the white rot fungus Kuehneromyces mutabilis (Schaeff.: Fr.) Singer & Smith (Km) in aseptic dual culture established on fertilized 100 mm-long wood dust columns in glass tubes with the inclusion of their volatilomes. For the mycelia approaching from the opposite ends of the wood dust columns, the energy-generating systems of laccase and manganese peroxidase (MnP), the virulence factor oxalate, and the exhalation of terpenes were determined by spectrophotometry, High Pressure Liquid Chromatography (HPLC), and Gas Chromatography-Mass Spectrometry (GC-MS). Km mycelia perceived the approaching Fp over 20 mm of non-colonized wood dust, reduced the laccase activity to 25%, and raised MnP to 275%–500% by gaining energy and presumably by controlling oxalate, H2O2, and the dropping substrate pH caused by Fp. On mycelial contact, Km stopped Fp, secured its substrate sector with 4 mm of an impermeable barrier region during an eruption of antimicrobial bisabolenes, and dropped from the invasion mode of substrate colonization into the steady state mode of low metabolic and defensive activity. The approaching Fp raised the oxalate production throughout to >20 g kg−1 to inactivate laccase and caused, with pH 1.4–1.7, lethal conditions in its substrate sector whose physiological effects on Km could be reproduced with acidity conditions incited by HCl. After a mean lag phase of 11 days, Fp persisting in a state of high metabolic activity overgrew and digested the debilitated Km thallus and terminated the production of oxalate. It is concluded that the factors contributing to the competitive advantage of F. pinicola in the colonization of wounded trees and pre-infected deadwood are the drastic long-term acidification of the timber substrate, its own insensitivity to extremely low pH conditions, its efficient control of the volatile mono- and sesquiterpenes of timber and microbial origin, and the action of a undefined blend of terpenes and allelopathic substances.

Characterisation of Extracts and Anti-Cancer Activities of Fomitopsis pinicola

Fomitopsis pinicola (Sw. Karst) is a common bracket fungus, with a woody texture. It is found predominantly in coniferous forests in temperate regions throughout Europe and Asia. Fomitopsis pinicola has been extensively used for medicinal purposes, particularly in Chinese and Korean traditional medicine. In this mini-review, the anti-cancer characteristics of F. pinicola extracts were investigated. In vitro experiments revealed the pro-apoptotic, anti-oxidant and anti-inflammatory properties of extracts, whilst two of three in vivo studies reported an inhibition of tumour growth and prolonged survival. Only studies wherein fungal specimens were sourced from Europe or Asia were included in this review, as samples sourced as F. pinicola from North America were probably not F. pinicola, but a different species. Although not one of the most revered fungal species, F. pinicola has been used as a medicinal fungus for centuries, as well as consumed as a health food supplement. To date, the results from only three in vivo studies, investigating anti-cancer properties, have been published. Further studies, using comprehensively identified specimens, are required to fully elucidate the anti-cancer properties of F. pinicola extracts.

An Italian Research Culture Collection of Wood Decay Fungi

One of the main aims of the University of Pavia mycology laboratory was to collect wood decay fungal (WDF) strains in order to deepen taxonomic studies, species distribution, officinal properties or to investigate potential applications such as biocomposite material production based on fungi. The Italian Alps, Apennines and wood plains were investigated to collect Basidiomycota basidiomata from living or dead trees. The purpose of this study was to investigate the wood decay strains of the Mediterranean area, selecting sampling sites in North and Central Italy, including forests near the Ligurian and Adriatic seas, or near the Lombardy lakes. The isolation of mycelia in pure culture was performed according to the current methodology and the identity of the strains was confirmed by molecular analyses. The strains are maintained in the Research Culture Collection MicUNIPV of Pavia University (Italy). Among the 500 WDF strains in the collection, the most interesting isolates from the Mediterranean area are: Dichomitus squalens (basidioma collected from Pinus pinea), Hericium erinaceus (medicinal mushroom), Inocutis tamaricis (white-rot agent on Tamarix trees), Perenniporia meridionalis (wood degrader through Mn peroxidase) and P. ochroleuca. In addition, strains of species related to the Mediterranean climate (e.g., Fomitiporia mediterranea and Cellulariella warnieri) were obtained from sites with a continental-temperate climate.

UsingFomitopsis pinicolafor bioinspired synthesis of titanium dioxide and silver nanoparticles, targeting biomedical applications

The current study proposes a bio-directed approach for the formation of titanium oxide and silver nanoparticles (TiO₂ and Ag NPs), using a wild mushroom, Fomitopsis pinicola, identified by 18S ribosomal RNA gene sequencing (gene accession no. MK635350) and phenotypic examination. NP synthesis was confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance UV-visible spectroscopy (DR-UV), and scanning and transmission electron microscopy (SEM/TEM). Furthermore, the impact of NPs on Escherichia coli and Staphylococcus aureus and a human colon cancer cell line (HCT) were evaluated by MIC/MBC and MTT assays, respectively, along with structural morphogenesis by different microscopy methods. The results obtained showed that TiO₂ and Ag NPs were found to be significantly active, however, slightly enhanced antibacterial and anticancer action was seen with Ag NPs (10–30 nm). Such NPs can be utilized to control and treat infectious diseases and colon cancer and therefore have potential in a range of biomedical applications.

This study proposes a bio-directed approach for the formation of titanium oxide and silver nanoparticles (TiO₂ and Ag NPs), using a wild mushroom, Fomitopsis pinicola, identified by 18S ribosomal RNA gene sequencing (gene accession no. MK635350) and phenotypic examination.

ANTIBACTERIAL ACTIVITY OF FOMITOPSIS BETULINA CULTURAL LIQUID

The antibacterial activity of Fomitopsis betulina cultural liquid (native, native concentrated, lyophilized, dried) against standard bacteria (Escherichia coli АТСС 25922, Pseudomonas aeruginosa АТСС 27853, Staphylococcus aureus АТСС 25923), and clinical isolates (Acinetobacter baumannii 50/1496 MBL, A. baumannii 88/2995 MBL, E. coli 116/3196 KPC, Klebsiella pneumoniae 6/509 ESBL, AmpC, KPC, P. aeruginosa 99/3066 MBL, P. aeruginosa 125/3343 MBL, S. haemoliticus 22/824 MRSA, S. aureus 134/3569 MRCNS) has been evaluated by the serial dilutions method. The antibacterial activity of F. betulina against S. haemoliticus and A. baumannii has been found for the first time. All samples of F. betulina cultural liquid demonstrated the inhibitory effect against standard bacterial strains at the minimum bactericidal concentration (MBC) ranging from >2.0 up to 18.75 mg/ml, and against multidrug-resistant clinical isolates with MBC from 7.8 up to 48.42 mg/ml. The dried F. betulina cultural liquid showed the highest antimicrobial activity against standard bacteria and clinical isolates, except A. baumannii 50/1496 MBL, while native concentrated cultural liquid was the most effective against this pathogen. The study showed that the antibacterial activity of the cultural liquid of F. betulina was improved by concentration and drying. The results obtained indicate that F. betulina cultural liquid contains alternative antimicrobial agents, useful for the treatment of bacterial diseases and might be a perspective substance for the pharmaceutical industries

How to resolve cryptic species of polypores: an example in Fomes

Species that cannot be easily distinguished based on morphology, but which form distinct phylogenetic lineages based on molecular markers, are often referred to as cryptic species. They have been proposed in a number of fungal genera, including the basidiomycete genus Fomes. The main aim of this work was to test new methods for species delimitation in cryptic lineages of polypores, and to define useful characters for species identification. A detailed examination of a number of different Fomes strains that had been collected and isolated from different habitats in Italy and Austria confirmed the presence of distinct lineages in the Fomes fomentarius clade. Our zero hypothesis was that the Mediterranean strains growing on Quercus represent a species which can be delimited based on morphological and physiological characters when they are evaluated in statistically relevant numbers. This hypothesis was tested based on phylogenetic analysis of the rDNA ITS region, morphological characters of basidiomes and pure cultures, growth rates and optimum growth temperature experiments, mycelial confrontation tests, enzyme activity tests and volatile organic compound (VOC) production. The Mediterranean lineage can unambiguously be delimited from F. fomentarius. A syntype of an obscure and previously synonymized name, Polyporus inzengae, represents the Mediterranean lineage that we recognize as Fomes inzengae, a distinct species. The rDNA ITS region is useful for delimitation of Fomes species. Moreover, also a variety of morphological characters including hymenophore pore size, basidiospore size, and diameter of skeletal hyphae are useful delimiting characters. The ecology is also very important, because the plant host appears to be a central factor driving speciation. Physiological characters turned also out to be species-specific, e.g. daily mycelial growth rates or the temperature range of pure cultures. The production of VOCs can be considered as a very promising tool for fast and reliable species delimitation in the future.

1H NMR-MS-based heterocovariance as a drug discovery tool for fishing bioactive compounds out of a complex mixture of structural analogues

Chemometric methods and correlation of spectroscopic or spectrometric data with bioactivity results are known to improve dereplication in classical bio-guided isolation approaches. However, in drug discovery from natural sources the isolation of bioactive constituents from a crude extract containing close structural analogues remains a significant challenge. This study is a ¹H NMR-MS workflow named ELINA (Eliciting Nature’s Activities) which is based on statistical heterocovariance analysis (HetCA) of ¹H NMR spectra detecting chemical features that are positively (“hot”) or negatively (“cold”) correlated with bioactivity prior to any isolation. ELINA is exemplified in the discovery of steroid sulfatase (STS) inhibiting lanostane triterpenes (LTTs) from a complex extract of the polypore fungus Fomitopsis pinicola.

The microbiome profiling of fungivorous black tinder fungus beetle Bolitophagus reticulatus reveals the insight into bacterial communities associated with larvae and adults

Saproxylic beetles play a crucial role in key processes occurring in forest ecosystems, and together with fungi contribute to the decomposition and mineralization of wood. Among this group are mycetophilic beetles which associate with wood-decaying fungi and use the fruiting body for nourishment and development. Therefore, their feeding strategy (especially in the case of fungivorous species) requires special digestive capabilities to take advantage of the nutritional value of fungal tissue. Although polypore-beetle associations have been investigated in numerous studies, detailed studies focusing on the microbiome associated with species feeding on fruiting bodies of polypores remain limited. Here we investigated the bacterial communities associated with larvae and adults of Bolitophagus reticulatus collected from Fomes fomentarius growing on two different host tree: beech (Fagus sp.) and birch (Betula sp.), respectively. Among 24 identified bacterial phyla, three were the most relatively abundant (Proteobacteria, Actinobacteria and Bacteroidetes). Moreover, we tried to find unique patterns of bacteria abundances which could be correlated with the long-term field observation showing that the fruiting bodies of F. fomentarius, growing on birch are more inhabited by beetles than fruiting bodies of the same fungus species growing on beech. Biochemical analyses showed that the level of protease inhibitors and secondary metabolites in F. fomentarius is higher in healthy fruiting bodies than in the inhabited ones. However, tested microbiome samples primarily clustered by developmental stage of B. reticulatus and host tree did not appear to impact the taxonomic distribution of the communities. This observation was supported by statistical analyses.

Fomes fomentarius Ethanol Extract Exerts Inhibition of Cell Growth and Motility Induction of Apoptosis via Targeting AKT in Human Breast Cancer MDA-MB-231 Cells

Fomes fomentarius, an edible mushroom, is known to have anti-cancer, anti-inflammatory, and anti-diabetes effects. However, the underlying anti-cancer mechanism of F. fomentarius is unknown. To determine the molecular mechanism of the anti-cancer effects of F. fomentarius, various methods were used including fluorescence-activated cell sorting, Western blotting, migration, and crystal violet assays. F. fomentarius ethanol extract (FFE) decreased cell viability in six cancer cell lines (MDA-MB-231, MCF-7, A549, H460, DU145, and PC-3). FFE decreased the migration of MDA-MB-231 cells without causing cell toxicity. Furthermore, FFE attenuated the expression of matrix metalloproteinase-9 and phosphorylation of Akt as well as increased E-cadherin in MDA-MB-231 cells. FFE arrested the S and G2/M populations by inhibiting the expression of cell cycle regulatory proteins such as cyclin-dependent kinase 2, cyclin A/E, and S-phase kinase-associated protein 2. FFE increased the sub-G1 population and expression of cleaved caspase-9, -3, and cleaved poly adenosine diphosphate (ADP-ribose) polymerase at 72 h and suppressed B-cell lymphoma 2. Interestingly, FFE and AKT inhibitors showed similar effects in MDA-MB-231 cells. Additionally, FFE contained betulin which inhibited p-AKT in MDA-MB-231 cells. Our findings demonstrate that FFE inhibits cell motility and growth and induces apoptosis by inhibiting the phsphoinositide 3- kinase /AKT pathway and caspase activation.

Leaves of Indoor Ornamentals Are Biodiversity and Functional Hotspots for Fungi

Leaf-inhabiting fungi are an important, but often overlooked component of molecular biodiversity studies. To understand their diversity and function in relation to plant species and climate, the phyllospheres of 14 phylogenetically diverse ornamental plant species were analyzed under different controlled greenhouse conditions. We found unexpectedly high fungal diversity (H' = 2.8-6.5), OTU numbers (449-1050) and abundances (103-106 CFU cm-2 leaf surface) associated with all plants studied indoors. Despite experimental limitations, the composition of fungal communities were inclined toward a plant species-dependent pattern compared to the ambient climatic variables. Most detected fungi were patho- and saprotrophs showing a yeast-like growth morphology and were associated to the groups of endophytes and potential plant pathogens in a plant species-specific manner. A representative strain collection showed that 1/3 of the tested fungi (mainly Penicillium, Cladosporium, and Cryptococcus spp.) were able to inhibit mycelial growth and 2/3 inhibit sporulation of the plant pathogen Botrytis cinerea by the production of antifungal volatile organic compounds (VOCs) completely. This study indicates that plant leaves harbor a stable phyllosphere fungal diversity in diverse microclimates and enrich distinctive functional guilds.

Identifying the "Mushroom of Immortality": Assessing the Ganoderma Species Composition in Commercial Reishi Products

Species of Ganoderma, commonly called reishi (in Japan) or lingzhi (in China), have been used in traditional medicine for thousands of years, and their use has gained interest from pharmaceutical industries in recent years. Globally, the taxonomy of Ganoderma species is chaotic, and the taxon name Ganoderma lucidum has been used for most laccate (shiny) Ganoderma species. However, it is now known that G. lucidum sensu stricto has a limited native distribution in Europe and some parts of China. It is likely that differences in the quality and quantity of medicinally relevant chemicals occur among Ganoderma species. To determine what species are being sold in commercially available products, twenty manufactured products (e.g., pills, tablets, teas, etc.) and seventeen grow your own (GYO) kits labeled as containing G. lucidum were analyzed. DNA was extracted, and the internal transcribed spacer (ITS) region and translation elongation factor 1-alpha (tef1α) were sequenced with specific fungal primers. The majority (93%) of the manufactured reishi products and almost half of the GYO kits were identified as Ganoderma lingzhi. G. lingzhi is native to Asia and is the most widely cultivated and studied taxon for medicinal use. Illumina MiSeq sequencing of the ITS1 region was performed to determine if multiple Ganoderma species were present. None of the manufactured products tested contained G. lucidum sensu stricto, and it was detected in only one GYO kit. G. lingzhi was detected in most products, but other Ganoderma species were also present, including G. applanatum, G. australe, G. gibbosum, G. sessile, and G. sinense. Our results indicate that the content of these products vary and that better labeling is needed to inform consumers before these products are ingested or marketed as medicine. Of the 17 GYO kits tested, 11 kits contained Ganoderma taxa that are not native to the United States. If fruiting bodies of exotic Ganoderma taxa are cultivated, these GYO kits will likely end up in the environment. The effects of these exotic species to natural ecosystems needs investigation.

A comprehensive screening shows that ergothioneine is the most abundant antioxidant in the wild macrofungus Phylloporia ribis Ryvarden

The polar and non-polar extracts from the authenticated wild mushroom Phylloporia ribis were separated by hydrophilic interaction liquid chromatography (HILIC) and by reverse phase (RP)-HPLC, respectively. A split valve separated the eluents into two fractions for free-radical scavenging analysis and for structural identification. Forty-six compounds showed scavenging activity of the stable-free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The structures of 8 antioxidants (inosine, caffeic acid, ergothioneine, p-hydroxybenzoic acid, adenosine, 3,4-dihydroxybenzaldehyde, apigenin, and naringenin) are characterized by Mass Spectrometer. Among them, ergothioneine was the most abundant (>65%) and most active antioxidant in P. ribis.

Fomitopsis betulina (formerly Piptoporus betulinus): the Iceman's polypore fungus with modern biotechnological potential

Higher Basidiomycota have been used in natural medicine throughout the world for centuries. One of such fungi is Fomitopsis betulina (formerly Piptoporus betulinus), which causes brown rot of birch wood. Annual white to brownish fruiting bodies of the species can be found on trees in the northern hemisphere but F. betulina can also be cultured as a mycelium and fruiting body. The fungus has a long tradition of being applied in folk medicine as an antimicrobial, anticancer, and anti-inflammatory agent. Probably due to the curative properties, pieces of its fruiting body were carried by Ötzi the Iceman. Modern research confirms the health-promoting benefits of F. betulina. Pharmacological studies have provided evidence supporting the antibacterial, anti-parasitic, antiviral, anti-inflammatory, anticancer, neuroprotective, and immunomodulating activities of F. betulina preparations. Biologically active compounds such as triterpenoids have been isolated. The mushroom is also a reservoir of valuable enzymes and other substances such as cell wall (1→3)-α-D-glucan which can be used for induction of microbial enzymes degrading cariogenic dental biofilm. In conclusion, F. betulina can be considered as a promising source for the development of new products for healthcare and other biotechnological uses.

DNA barcoding for identification of consumer-relevant mushrooms: A partial solution for product certification?

One challenge in the dietary supplement industry is confirmation of species identity for processed raw materials, i.e. those modified by milling, drying, or extraction, which move through a multilevel supply chain before reaching the finished product. This is particularly difficult for samples containing fungal mycelia, where processing removes morphological characteristics, such that they do not present sufficient variation to differentiate species by traditional techniques. To address this issue, we have demonstrated the utility of DNA barcoding to verify the taxonomic identity of fungi found commonly in the food and dietary supplement industry; such data are critical for protecting consumer health, by assuring both safety and quality. By using DNA barcoding of nuclear ribosomal internal transcribed spacer (ITS) of the rRNA gene with fungal specific ITS primers, ITS barcodes were generated for 33 representative fungal samples, all of which could be used by consumers for food and/or dietary supplement purposes. In the majority of cases, we were able to sequence the ITS region from powdered mycelium samples, grocery store mushrooms, and capsules from commercial dietary supplements. After generating ITS barcodes utilizing standard procedures accepted by the Consortium for the Barcode of Life, we tested their utility by performing a BLAST search against authenticate published ITS sequences in GenBank. In some cases, we also downloaded published, homologous sequences of the ITS region of fungi inspected in this study and examined the phylogenetic relationships of barcoded fungal species in light of modern taxonomic and phylogenetic studies. We anticipate that these data will motivate discussions on DNA barcoding based species identification as applied to the verification/certification of mushroom-containing dietary supplements.

Phellinus igniarius: A Pharmacologically Active Polypore Mushroom

Mushrooms have been widely used in traditional medicine for the treatment of various diseases. Today, their therapeutic value is scientifically studied and appreciated. Research indicates that polypores - a large group of fungi of the phylum Basdiomycota - exhibit antiviral, antimicrobial, anticancer, anti-allergic, anti-atherogenic, hypoglycemic, hepatoprotective and anti-inflammatory activities. Phellinus igniarius, a polypore mushroom, is one of the most used in traditional Asian medicine. Its potent anticancer activity has been repeatedly reported. In the past two decades, numerous pharmacologically active metabolites have been isolated and identified from P. igniarius. Among the large number of compounds, the most active group are polysaccharides. They modulate immune responses and inhibit tumor growth.

Colony-PCR Is a Rapid Method for DNA Amplification of Hyphomycetes

Fungal pure cultures identified with both classical morphological methods and through barcoding sequences are a basic requirement for reliable reference sequences in public databases. Improved techniques for an accelerated DNA barcode reference library construction will result in considerably improved sequence databases covering a wider taxonomic range. Fast, cheap, and reliable methods for obtaining DNA sequences from fungal isolates are, therefore, a valuable tool for the scientific community. Direct colony PCR was already successfully established for yeasts, but has not been evaluated for a wide range of anamorphic soil fungi up to now, and a direct amplification protocol for hyphomycetes without tissue pre-treatment has not been published so far. Here, we present a colony PCR technique directly from fungal hyphae without previous DNA extraction or other prior manipulation. Seven hundred eighty-eight fungal strains from 48 genera were tested with a success rate of 86%. PCR success varied considerably: DNA of fungi belonging to the genera Cladosporium, Geomyces, Fusarium, and Mortierella could be amplified with high success. DNA of soil-borne yeasts was always successfully amplified. Absidia, Mucor, Trichoderma, and Penicillium isolates had noticeably lower PCR success.