Search Results (48)

Pulsed electric field (PEF) has previously been recognized as a method of gentle food processing, and its use has been shown to be helpful in reducing the levels of toxigenic Fusarium micromycetes developed during malting. The aim of this study was to describe the effects of PEF on gene expression and metabolite production at the pre-finishing stage of barley malting by using a novel multi-omics data-driven approach. The study helps to uncover the processes occurring in the germinated grain and discusses the up-/downregulation of genes and metabolites in relation to fungal infection and/or PEF-induced abiotic stress. Among the factors upregulated by PEF and previously described as supportive against Fusarium diseases, we identified the increased expression of genes encoding vegetative gp1-like protein, which positively correlated with flavonoids, (methylsulfanyl)prop-2-enoates, triterpenoid glycosides, and indole alkaloids. On the other hand, some genes associated with barley resistance to fungal infection were also overexpressed in the untreated control (in particular, genes encoding ethylene response factor 3-like, putrescine hydroxycinnamoyltransferase 3-like, and dirigent protein 21-like). This study provides the first ‘data-driven’ basic research results that contribute to the understanding of the role of PEF as an effective fungal decontamination strategy and allows the formulation of new hypotheses related to Fusarium pathogen crosstalk. Full article

Owing to their nutritional, culinary, and nutraceutical, mushrooms are worldwide consumed and appreciated. Moreover, many of these mushrooms are also known as medicinal mushrooms since they possess several pharmacological properties attributable to a huge number of bioactive compounds derived from their sporophores. Several studies are available in the literature about in vitro and in vivo mechanisms of actions of such bioactive compounds. Most of these surveys are focused on macrofungi belonging to the genera Pleurotus, Ganoderma, or specific taxa such as Agaricus bisporus, Agaricus blazei, Boletus eduliInonotus obliquus, Hericium erinaceus, Lentinula edodes, and Grifola frondose. On the other hand, there is a lack of information on the under investigated ecological group of freshwater fungi. These fungi play a very important role in freshwater environments and some of them, belonging to Basidiomycota, are also edible and largely consumed. In this review we collected information about the medicinal properties of freshwater macro- and micromycetes. Among them, macrofungi, such as Amanita vaginata, Armillaria mellea, Armillaria tabescens, Astraeus hygrometricus, Auricularia auricula-judae, Bjerkandera adusta, Bovista nigrescens, Calocybe gambosa, Candolleomyces candolleanus, Collybia dryophila, Coprinus comatus, Cyclocybe cylindracea, Hypsizygus ulmarius, Inonotus hispidus, Lactarius controversus, Lentinus tigrinus, and Schizophyllum commune, observed in riparian habitat, and microfungi, such as Penicillium aculeatum, P. chrysogenum, and Fusarium incarnatum, isolated from aquatic plants, have been reported to have antimicrobial, anticancer, anti-inflammatory, antioxidant, antidiabetic, immunomoludatory, hypoglycaemic, and other pharmaceutical activities. Such fungal species are noteworthy since they represent an important quote of biodiversity to preserve their fundamental ecological role and a possible solution for different health problems for humans and animal farms. Full article

In order to meet the ever-growing needs of society, modern agriculture must develop sustainable farming and livestock production. Crops need phosphorus, a macronutrient found in soils, but they are only able to utilize small quantities of it. Chemical phosphate fertilizers are ineffective and environmentally harmful. The use of microorganisms (bacteria, yeast, filamentous fungi, and microalgae) that synthesize phytases is a promising and environmentally friendly alternative to chemical fertilizers. Phytases are also needed as feed additives in animal husbandry to overcome phosphorus deficiency for animal growth and development. Phytases are phosphatases that catalyze the release of phosphorus from phytate by stepwise hydrolysis. The broad substrate specificity, optimal pH range, higher thermal stability, and specific efficiency of fungal phytases make them interesting enzymes for agricultural applications. They improve and stimulate the growth and development of plants and animals by releasing inorganic phosphorus and producing siderophores, organic acids, hydrogen cyanide, ammonia, and phytohormones. Phytases are crucial for enhancing phosphorus use in farming and decreasing phosphorus waste’s environmental effects. This paper addresses key challenges in modern farming, such as the inefficient utilization of phosphorus from soil and the environmental harm caused by chemical fertilizers, and provides a comprehensive overview of recent advances in the research of fungal phytases. Available scientific data have been synthesized to highlight the potential of phytase use in agriculture. This review outlines key areas for future research, including the development of phytase variants with improved functionality. The potential integration of fungal phytases into sustainable agricultural practices is underlined, in contrast to previously published work focused primarily on their biochemical properties. The review offers new insight into the possible applications of micromycete phytases as a critical factor for sustainable agriculture in the future. Full article

The increasing contamination of cereals by micromycetes and mycotoxins during malting still poses an unresolved food safety problem. This study characterises the potential of the novel, rapidly developing food production technology of Pulsed Electric Field (PEF) to reduce the viability of Fusarium fungi and the production of mycotoxins during malting. Barley, artificially inoculated with four Fusarium species, was treated by PEF with two different intensities and then malted using a standard Pilsner-type technology. Concentrations of fungi were quantified by RT-PCR, expression of fungal growth-related genes was assessed using mRNA sequencing, and mycotoxin levels were analysed by U-HPLC-HRMS/MS. Despite the different trends for micromycetes and mycotoxins after application of variously intense PEF conditions, significant reductions were generally observed. The greatest decrease was for F. sporotrichioides and F. poae, where up to six fold lower levels were achieved for malts produced from the PEF-treated barley when compared to the control. For F. culmorum and F. graminearum, up to a two-fold reduction in the PEF-generated malts was observed. These reductions mostly correlated with a decrease in relevant mycotoxins, specifically type A trichothecenes. Full article

The present study demonstrated the differences in the seed metabolome and mycobiome of two Aegilops tauschii Coss accessions with different resistance to brown rust and powdery mildew. We hypothesized that the seeds of resistant accession k-1958 Ae. tauschii ssp. strangulata can contain a larger number of metabolites with antifungal activity compared with the seeds of susceptible Ae. tauschii ssp meyeri k-340, which will determine differences in the seed fungal community. Our study emphasizes the differences in the seed metabolome of the studied Ae. tauschii accessions. The resistant accession k-1958 had a higher content of glucose and organic acids, including pyruvic, salicylic and azelaic acid, as well as pipecolic acids, galactinol, glycerol and sitosterol. The seeds of Ae. tauschii-resistant accession k-1958 were found to contain more active substances with antifungal activity. The genera Cladosporium and Alternaria were dominant in the seed mycobiome of the resistant accession. The genera Alternaria, Blumeria and Cladosporium dominated in seed mycobiome of susceptible accession k-340. In the seed mycobiome of the resistant k-1958, a higher occurrence of saprotrophic micromycetes was found, and many of the micromycetes were biocontrol agents. It was concluded that differences in the seed metabolome of Ae. tauschii contributed to the determination of the differences in mycobiomes. Full article

Soil and sediment host microorganisms are able to survive in extremely resource-limited environments. Therefore, more and more attention is being paid to cave sediments as a reservoir of microbiota. The aim of this study is the speleomycological evaluation of the culturable soil and sediment fungal communities in the Brestovská Cave. To explore the origins of fungi, speleomycological studies were conducted both inside and outside the cave under investigation. Additionally, two incubation temperatures (5 and 24 °C) were used to increase the species spectrum of isolated fungi. To achieve the most accurate species identification, we combined an assessment of morphological characteristics of the isolates with molecular sequencing (ITS, internal transcribed spacer). Twenty different species were found and the most frequent was Penicillium commune, followed by Trichosporiella cerebriformis and Pseudogymnoascus pannorum. To our knowledge, our study has enabled the first identification of fungal species such as Penicillium swiecicki, Cephalotrichum hinnuleum, Cosmpospora berkeleyana, Lecythophora hoffmannii, Ambomucor seriatoinflatus, and Mortierella minutissima in underground sites. Our data showed that the abundance and composition of the fungal community varied between the indoor and outdoor samples and thus from the entrance and less visited sites deeper in the cave. Full article

Rock-inhabiting fungi (RIF) are usually extremely tolerant or extremophilic, as they can survive on natural and artificial rocks despite being exposed to stressful conditions. RIF have serious negative effects on the appearance and cohesion of rocky substrates, causing the alteration and decomposition of building materials, but also on human and animal health, as they can act as opportunistic pathogens. Their identification is therefore of great importance, especially in urban areas. In the present study, culturing techniques for isolating fungi, and a polyphasic taxonomic approach to their identification, were used to assess the diversity of micromycetes that darken the surfaces of buildings in various villages and cities in Tarragona Province (Spain). Sixty-four species of RIF belonging to forty-one genera were identified, including a new genus (Coccodomyces) and the following six new fungal species: Coccodomyces pleiosporus, Exophiala caementiphila, Exophiala multiformis, Neocatenulostroma spinulosum, Neodevriesia longicatenispora, and Paradevriesia holothallica. Thus, we have established that building materials are ecological niches where a high biodiversity of RIF can develop. Full article

Relationships between different microorganisms’ groups and the soil environment are reversible, and the state of the soil and its provided services can also change the structure and abundance of microorganisms as well as that microorganisms can affect soil conditions. The aim of our research was to analyze the physical and chemical properties of differently formed agroecosystems, which are affected by different anthropogenic pressures and to compare how bacterial composition differ in totally different environments. It was established that different soil microorganisms’ physiological groups significantly correlated with chemical and physical soil properties: atmospheric nitrogen-fixing bacteria showed a positive correlation with soil pH_KCl, N_sum, P₂O₅, and soil bulk density; meanwhile, soil porosity, and the K₂O amount in the soil negatively affected the population of atmospheric nitrogen-fixing bacteria. The same tendencies were inherent to actinomycetes and ammonifying bacteria. Micromycetes showed a negative trend with soil pH_KCl, showing that soils with lower pH_KCl are characterized by a higher abundance of micromycetes. Analysis of the taxonomic diversity of soil microbes reveals that the bacterial communities were dominated by two main species of bacteria: Betaproteobacterium and Candidatus Saccharibacteria. Bacterial identification shows that the main bacterial species were the same in all analyzed sampling places despite the different anthropogenic activities, parent material, and other abiotic conditions. Only a few species were identified in different soil groups, and it may be assumed that those groups could be potential bioindicators for specific soil types, but more in depth research is needed to confirm this hypothesis. Full article

The paper searches for new solutions for the development of highbush blueberry orchards (Vaccinium corymbosum L. (1753)) in Western Siberia. All species of the genus Vaccinium display special symbiotic mycorrhizal associations with root systems—ericoid mycorrhiza, which essentially enhances the formation of adventitious and lateral roots. For the first time, we obtained pure cultures of micromycetes associated with the roots of wild species of the family Ericaceae in the Tomsk region, Russia. With regard to the data of molecular genetic analysis of the ITS region sequence, we selected the BR2-1 isolate based on its morphophysiological traits, which was assigned to the genus Leptodophora. Representatives of this genus typically enter into symbiotic relationships with heathers to form ericoid mycorrhizae. We studied the effect of strain BR2-1 on the development of microclones of the highbush blueberry var. Nord blue during their in vitro adaptation and showed its beneficial effect on growth and shoot formation in young plants. Experiments performed using submerged and solid-state methods showed that the most optimal method for commercial production of BR2-1 is cultivation on grain sterilized by boiling, followed by spore washing. Full article

The formation of oxalates in soils and rocks under conditions of cryoarid climate, permafrost and taiga vegetation was studied. Whewellite and weddellite were found in four areas associated with the mining industry: on the kimberlite deposit of the Daldyn territory, in the lower reaches of the Markha River of the Central Yakut Plain, and on the coastal outcrop of the Allah-Yun Sellah-Khotun ore cluster. Whewellite was found in the upper organic horizon of Skeletic Cryosol (Thixotropic) (sample 151) and as a film on the surface of plant remains of Humic Fluvisols (sample 1663). Weddellite was found as an extensive encrustation on the surface of the soil and vegetation cover of Stagnic Cryosols Reductaquic (sample 984) and on a siltstone outcrop (sample KM-6-21). Calcium oxalates were identified by X-ray phase analysis, photographs of the samples were taken on a polarizing microscope, and the crystal morphology was studied on a scanning electron microscope. To determine the chemical composition of soils and rocks, the classical wet-chemical method was used; the physical properties of the studied samples were studied using a pH meter, the photoelectric colorimetric method, and a synchrotron thermal analysis device. The source of calcium for the formation of salts is the parent layers of the studied soils, represented by carbonate and carbonate clastic rocks, which cause neutral and slightly alkaline environments. High humidity, which is provided by the seasonal thawing of the permafrost, has a key role in the formation of the studied oxalates in Yakutia with a sharply continental cryoarid climate. Based on the studies, it was found that the first two samples are the products of lichen activity, and the third and fourth are at the stage of initial soil formation by micromycetes. In addition, the formation of these oxalates, in our opinion, is the result of the protective function of vegetation, in the first two cases, with a sharp increase in the load on lichens under technogenic impact, and in the second and third cases, when favorable conditions arise for initial soil formation, but under conditions of toxic content of heavy metals and arsenic. Full article

Humans are constantly exposed to micromycetes, especially filamentous fungi that are ubiquitous in the environment. In the presence of risk factors, mostly related to an alteration of immunity, the non-dermatophyte fungi can then become opportunistic pathogens, causing superficial, deep or disseminated infections. With new molecular tools applied to medical mycology and revisions in taxonomy, the number of fungi described in humans is rising. Some rare species are emerging, and others more frequent are increasing. The aim of this review is to (i) inventory the filamentous fungi found in humans and (ii) provide details on the anatomical sites where they have been identified and the semiology of infections. Among the 239,890 fungi taxa and corresponding synonyms, if any, retrieved from the Mycobank and NCBI Taxonomy databases, we were able to identify 565 moulds in humans. These filamentous fungi were identified in one or more anatomical sites. From a clinical point of view, this review allows us to realize that some uncommon fungi isolated in non-sterile sites may be involved in invasive infections. It may present a first step in the understanding of the pathogenicity of filamentous fungi and the interpretation of the results obtained with the new molecular diagnostic tools. Full article

Europe’s forests, particularly in Ukraine, are highly vulnerable to climate change. The maintenance and improvement of forest health are high-priority issues, and various stakeholders have shown an interest in understanding and utilizing ecological interactions between trees and their associated microorganisms. Endophyte microbes can influence the health of trees either by directly interacting with the damaging agents or modulating host responses to infection. In the framework of this work, ten morphotypes of endophytic bacteria from the tissues of unripe acorns of Quercus robur L. were isolated. Based on the results of the sequenced 16S rRNA genes, four species of endophytic bacteria were identified: Bacillus amyloliquefaciens, Bacillus subtilis, Delftia acidovorans, and Lelliottia amnigena. Determining the activity of pectolytic enzymes showed that the isolates B. subtilis and B. amyloliquefaciens could not cause maceration of plant tissues. Screening for these isolates revealed their fungistatic effect against phytopathogenic micromycetes, namely Fusarium tricinctum, Botrytis cinerea, and Sclerotinia sclerotiorum. Inoculation of B. subtilis, B. amyloliquefaciens, and their complex in oak leaves, in contrast to phytopathogenic bacteria, contributed to the complete restoration of the epidermis at the sites of damage. The phytopathogenic bacteria Pectobacterium and Pseudomonas caused a 2.0 and 2.2 times increase in polyphenol concentration in the plants, respectively, while the ratio of antioxidant activity to total phenolic content decreased. Inoculation of Bacillus amyloliquefaciens and Bacillus subtilis isolates into oak leaf tissue were accompanied by a decrease in the total pool of phenolic compounds. The ratio of antioxidant activity to total phenolic content increased. This indicates a qualitative improvement in the overall balance of the oak leaf antioxidant system induced by potential PGPB. Thus, endophytic bacteria of the genus Bacillus isolated from the internal tissues of unripe oak acorns have the ability of growth biocontrol and spread of phytopathogens, indicating their promise for use as biopesticides. Full article

A synbiotic preparation based on two strains of B. licheniformis was developed to reduce the harmful effects of mycotoxins in postharvest products used for cattle feed. The genomes of these strains were sequenced to analyze their potential for producing bioactive secondary metabolites. An optimal substrate was selected from the variety of plant substrates, with soybeans being identified as the optimal choice. Based on the results of experiments conducted on experimental animals for a month, the introduction of a synbiotic preparation leveled the negative effect of mycotoxins on weight gain in heifer calves, bringing it to the level of the control groups. There was also a decrease in the level of alkaline phosphatase in serum to normal values, which may indicate the probiotic effects of the preparation, not associated with the elimination of the effect of mycotoxins. The activity of these strains against mycotoxins correlates with the presence of lactonase genes in their genomes. Antimicrobial and bioactive metabolites, such as lichenicidin and lichenisin synthesized by strains CL 33 and CL 56, also seem to contribute to the probiotic effect. The results of the study open up prospects for the creation of new synbiotic preparations to fight contamination with mycotoxins. Full article

Spiked centaury (Centaurium spicatum) is a well-known medicinal plant from the Mediterranean region with various bioactivities, but there are no studies addressing the use of different solvent systems to improve its pharmacological potential. Nine extraction procedures were adapted to study the effects of solvent composition on the content of bioactive compounds in C. spicatum extracts and on corresponding bioactivities. Targeted metabolomics was performed to obtain information on the chemical composition of extracts. Ethanol-water-based extraction procedures were the most efficient in isolating polyphenols, while less polar butanol extract contained the highest amount of iridoids. Antioxidant potential analysis revealed stronger activity in extracts with higher polyphenol content. Bacillus cereus and Staphylococus aureus were designated as the most sensitive bacterial strains to the activity of extracts, while among the micromycetes tested, Penicillium funiculosum was the most susceptible strain. Butanol extract showed antivirulence potential on Candida albicans morphological transition from yeast to hyphal form, and selected extracts were effective against biofilm formation in two Candida species. All the extracts tested in this study showed no cytotoxic activity to immortalize human skin keratinocyte cell line (HaCaT), whereas extracts obtained by ethanol-water extraction stand out for their potent wound healing effects. Moreover, the influence of the extraction solvent system on various bioactivities of C. spicatum is reported herein for the first time. Overall, the results presented in this study promote the use of C. spicatum as a source of natural products with potential antioxidant, wound healing, and antimicrobial applications that are potentially safe for human use. Full article

This study of a legume’s rhizosphere in tripartite symbiosis focused on the relationships between the symbionts and less on the overall rhizosphere microbiome. We used an experimental model with different garden pea genotypes inoculated with AM fungi (Rhizophagus irregularis and with a mix of AM species) to study their influence on the population levels of main trophic groups of soil microorganisms as well as their structure and functional relationships in the rhizosphere microbial community. The experiments were carried out at two phenological cycles of the plants. Analyzes were performed according to classical methods: microbial population density defined as CUF/g a.d.s. and root colonization rate with AMF (%). We found a proven dominant effect of AMF on the densities of micromycetes and actinomycetes in the direction of reduction, suggesting antagonism, and on ammonifying, phosphate-solubilizing and free-living diazotrophic Azotobacter bacteria in the direction of stimulation, an indicator of mutualistic relationships. We determined that the genotype was decisive for the formation of populations of bacteria immobilizing mineral NH₄⁺-N and bacteria Rhizobium. We reported significant two-way relationships between trophic groups related associated with soil nitrogen and phosphorus ions availability. The preserved proportions between trophic groups in the microbial communities were indicative of structural and functional stability. Full article