The Antarctic ecosystems are a combination of conditions, including extremely low values of temperature and humidity. Nonetheless, some organisms, such as fungi, can adapt to these extreme conditions. The environmental temperature is one of the parameters thoroughly affecting the structure and composition of fungal membrane lipids. The psychrophilic fungi generally increase the disorder within macromolecules to maintain membrane fluidity at low temperatures. To do so, Antarctic fungi increase the proportion of unsaturated fatty acids that allow maintaining a semi-fluid state of the membranes and survive at extremely low temperatures. This ecological feature may be of interest for the characterization of phenotypical traits of the ecological adaptation of these fungi to the extreme environmental conditions of Antarctica. Moreover, this can be of inspiration to find solutions inspired by nature for alternative sources of polyunsaturated fatty acids (PUFAs) for diets of humans and animals. We characterized three fungal strains isolated from Antarctica and set up a laboratory/small-scale production of fungal biomass with a high content of beneficial PUFAs. In detail, three fungal species previously isolated from Antarctic environmental matrices were tested and identified at the genome level. We also conducted growth experiments to determine the effects of temperature and substrate on biomass and PUFA production. The results showed that these fungi have a high percentage of PUFAs compared to saturated ones; the growth at low temperatures (10°C) increases the production of linolenic acid (C18:3) while the biomass amount (yield) depends on the composition of the growth substrate; a satisfying qualitative-quantitative production is achieved using agri-food chain waste products, such as brewing and whey waste, as a growth substrate.IMPORTANCEThe presence of polyunsaturated fatty acids (PUFAs) in the diets of humans and animals is gaining attention because PUFAs have several recognized functional properties: they modulate immune response, have anti-allergic and anti-inflammatory activity, have a cardio-protective effect, and reduce blood LDL cholesterol levels. Since few foods naturally contain high levels of PUFAs, human diets are often deficient in these fatty acids, which is why supplementation is often needed. Regarding this, it is necessary to develop efficient industrial processes capable of producing good-quality PUFAs and in quantity, even using agri-food chain waste products as carbon and nitrogen sources (in our case, spent yeast from brewing and whey waste). Like microorganisms, we took into consideration Antarctic fungi because they can adapt to very low temperatures also by increasing the proportion of unsaturated fatty acids that allows maintaining a semi-fluid state of their membranes. The innovation of our study consists of a characterization of phenotypical traits on PUFA production by fungal strains from Antarctica in different cultural conditions, including the use of agri-food processing wastes. The combination of these conditions can be an inspiration for a new, alternative, and sustainable way to produce PUFAs with extreme microorganisms.

ABSTRACT The Antarctic ecosystem is a combination of conditions including extremely low values of temperature. The environmental temperature is one of the parameters thoroughly affecting the structure and composition of fungal membranes lipids. The psychrophilic fungi generally increase the disorder within macromolecules to maintain membrane fluidity at low temperatures. The strategy adopted by Antarctic fungi is to increase the proportion of unsaturated fatty acid that allows maintaining a semi-fluid state of the membranes. This ecological feature might be exploited for using Antarctic fungi as potential alternative source of polyunsaturated fatty acids (PUFAs) for human diet. This study provides both the characterization of fungal strains isolated from Antarctica by lipidomic analysis and the laboratory/large-scale production of fungal biomass with high content of beneficial PUFAs. In detail, three fungal species isolated from environmental matrices from Antarctica were tested and identified at genome level. Growth experiments to evaluate the influence of temperature and substrate in the yield in biomass and unsaturated fatty acid (UFA) were conducted. The results showed that the selected fungi have a high percentage of UFA compared to saturated ones; low growth temperatures increase the yield in linolenic fatty acid (C18:3); the biomass yield depends on the composition of the growth substrate and a satisfying qualitative-quantitative yield has also been obtained by using an agri-food chain waste product as growth substrate. IMPORTANCE The presence of polyunsaturated fatty acids (PUFAs) in human and animal diet is gaining attention because PUFAs have several recognized functional properties: they modulate immune response, have anti-allergic and anti-inflammatory activity, cardio-protective effect and reduce blood LDL cholesterol levels. Human diets typically do not contain sufficient PUFAs because foods rich in PUFAs are few and it is therefore necessary to supplement this diet. Food supplements with these types of fatty acid currently commercially available come from marine fish oils and this source is no longer sustainable. It is necessary to develop efficient industrial processes capable of producing good quality PUFAs and in quantity, even using as carbon and nitrogen sources agro-industrial chains’ (in our case spent yeast from brewing and whey waste) waste products. Like microorganisms we used Antarctic fungi because they are adapted at very low temperature increasing the proportion of unsaturated fatty acid that allows maintaining a semi-fluid state of the membranes.

Trichoderma hamatum FBL 587 isolated from DDT-contaminated agricultural soils stands out as a remarkable strain with DDT-resistance and the ability to enhance DDT degradation process in soil. Here, whole genome sequencing and RNA-Seq studies for T. hamatum FBL 587 under exposure to DDT were performed. In the 38.9 Mb-genome of T. hamatum FBL 587, 10,944 protein-coding genes were predicted and annotated, including those of relevance to mycoremediation such as production of secondary metabolites and siderophores. The genome-scale transcriptional responses of T. hamatum FBL 587 to DDT exposure showed 1706 upregulated genes, some of which were putatively involved in the cellular translocation and degradation of DDT. With regards to DDT removal capacity, it was found upregulation of metabolizing enzymes such as P450s, and potentially of downstream DDT-transforming enzymes such as epoxide hydrolases, FAD-dependent monooxygenases, glycosyl- and glutathione-transferases. Based on transcriptional responses, the DDT degradation pathway could include transmembrane transporters of DDT, antioxidant enzymes for oxidative stress due to DDT exposure, as well as lipases and biosurfactants for the enhanced solubility of DDT. Our study provides the first genomic and transcriptomic data on T. hamatum FBL 587 under exposure to DDT, which are a base for a better understanding of mycoremediation strategies for DDT-polluted sites.

The study of the soil microbial community represents an important step in better understanding the environmental context. Therefore, biological characterisation and physicochemical integration are keys when defining contaminated sites. Fungi play a fundamental role in the soil, by providing and supporting ecological services for ecosystems and human wellbeing. In this research, 52 soil fungal taxa were isolated from in situ pilot reactors installed to a contaminated site in Czech Republic with a high concentration of hexachlorocyclohexane (HCH). Among the identified isolates, 12 strains were selected to evaluate their tolerance to different isomers of HCH by using specific indices (Rt:Rc; T.I.) and to test their potential in xenobiotic biotransformation. Most of the selected taxa was not significantly affected by exposure to HCH, underlining the elevated tolerance of all the tested fungal taxa, and different metabolic intermediates of HCH dechlorination were observed. The oxidative stress responses to HCH for two selected species, Penicillium simplicissimum and Trichoderma harzianum, were investigated in order to explore their toxic responses and to evaluate their potential functioning in bioremediation of contaminated environments. This research suggests that the isolated fungal species may provide opportunities for new eco-friendly, integrated and cost-effective solutions for environmental management and remediation, considering their efficient adaptation to stressful conditions.

In this study, we propose a new genus, Victoriomyces, with a new species, Victoriomyces antarcticus, isolated from soil samples collected in Victoria Land, Antarctica. To determine its taxonomic status and evolutionary relationships, phylogenetic analysis was performed on DNA sequences from the nuclear 18S rRNA, 28S rRNA and the second largest subunit of RNA polymerase II (RPB2) genes. Victoriomyces antarcticus constitutes one well-supported distinct lineage within the Cephalothecaceae (family incertae sedis in Sordariomycetes), in which the only recognised asexual morphs belong to the genus Phialemonium and to Acremonium thermophilum. Victoriomyces antarcticus can be clearly distinguished from these taxa by means of DNA sequence analysis and its morphological traits that consist in having a Metarhizium-like asexual morph, dark red-coloured disk-like structures, immature bodies and the production of an intense red pigment in the growth media. Finally, we inferred the divergence time of V. antarcticus and the Cephalothecaceae using Bayesian analysis and secondary calibration. The holotype of V. antarcticus is FBL 165. The ex-type strain has been deposited as MUT 3686T and CCF 6158T. An additional strain of the species is FBL 577. The MycoBank number is MB 823713 for the genus and MB 823714 for the species.

DDT (dichlorodiphenyltrichloroethane) was used worldwide as an organochlorine insecticide to control agricultural pests and vectors of several insect-borne human diseases. It was banned in most industrialized countries; however, due to its persistence in the environment, DDT residues remain in environmental compartments, becoming long-term sources of exposure. To identify and select fungal species suitable for bioremediation of DDT-contaminated sites, soil samples were collected from DDT-contaminated agricultural soils in Poland, and 38 fungal taxa among 18 genera were isolated. Two of them, Trichoderma hamatum FBL 587 and Rhizopus arrhizus FBL 578, were tested for tolerance in the presence of 1-mg liter-1 DDT concentration by using two indices based on fungal growth rate and biomass production (the tolerance indices Rt:Rc and TI), showing a clear tolerance to DDT. The two selected strains were studied to evaluate catabolic versatility on 95 carbon sources with or without DDT by using the Phenotype MicroArray system and to investigate the induced oxidative stress responses. The two strains were able to use most of the substrates provided, resulting in both high metabolic versatility and ecological functionality in the use of carbon sources, despite the presence of DDT. The activation of specific metabolic responses with species-dependent antioxidant enzymes to cope with the induced chemical stress has been hypothesized, since the presence of DDT promoted a higher formation of reactive oxygen species in fungal cells than the controls. The tested fungi represent attractive potential candidates for bioremediation of DDT-contaminated soil and are worthy of further investigations.IMPORTANCE The spread and environmental accumulation of DDT over the years represent not only a threat to human health and ecological security but also a major challenge because of the complex chemical processes and technologies required for remediation. Saprotrophic fungi, isolated from contaminated sites, hold promise for their bioremediation potential toward toxic organic compounds, since they might provide an environment-friendly solution to contamination. Once we verified the high tolerance of autochthonous fungal strains to high concentrations of DDT, we showed how fungi from different phyla demonstrate a high metabolic versatility in the presence of DDT. The isolates showed the singular ability to keep their functionality, despite the DDT-induced production of reactive oxygen species.

Modern agriculture is dependent on phosphate rock (PR), which is a nonrenewable resource. Improvement of phosphorus (P) availability for crops in agricultural soils represents a key strategy to slow down the depletion of PR. The aim of this study was to identify potential P biofertilisers among saprotrophic fungal species. We tested 30 fungal strains belonging to 28 taxa (4 Zygomycota and 24 Ascomycota) and with different life strategies. The study showed that many saprotrophic fungi have the ability to mobilise P from insoluble forms according to a variety of mechanisms. Our results expand the pool of P solubilising fungal species, also suggesting a new solubilisation index and shedding light on parameters that could be basic in the selection of efficient soil P-biofertilisers fungi. Rhizopus stolonifer var. stolonifer, Aspergillus niger and Alternaria alternata were found to be the best performing strains in terms of amounts of TCP solubilisation.

The saprotrophic fungus Penicillium griseofulvum was chosen as model organism to study responses to a mixture of hexachlorocyclohexane (HCH) isomers (α-HCH, β-HCH, γ-HCH, δ-HCH) and potentially toxic metals (vanadium, lead) in solid and liquid media. The P. griseofulvum FBL 500 strain was isolated from polluted soil containing high concentrations of HCH isomers and potentially toxic elements (Pb, V). Experiments were performed in order to analyse the tolerance/resistance of this fungus to xenobiotics and to shed further light on fungal potential in inorganic and organic biotransformations. The aim was to examine the ecological and bioremedial potential of this fungus verifying the presence of mechanisms that allow it to transform HCH isomers and metals under different extreme test conditions. To our knowledge, this work is the first to provide evidence on the biotransformation of HCH mixtures, in combination with toxic metals, by a saprotrophic non-white-rot fungus and on the metabolic synergies involved.

The metabolic efficiency of different microbial groups in carbon source uses and single species storage efficiency is poorly characterised and not adequately represented in most biogeochemical models. It is proposed here a simple approach for an estimation of the metabolic quotient of fungal isolates. The method is based on the values of substrate use (respiration) and growth (biomass production) obtainable for single fungal isolates in vitro using the Phenotype MicroArray system to test the metabolic performance of fungi on different substrates. As a case study, this carbon-use efficiency method was used to compare a group of leaf litter fungi. The metabolic efforts of single fungal species were measured on 95 different substrates of different complexity. The respiration to biomass ratio showed a high reliability and the possibility of being used as a measurable property of the micro-organisms and an indicator of organism's performance or fitness.

A trapping system was set up to isolate culturable cellulolytic fungi at the soil-leaf litter interface in an area of Mediterranean maquis located in southern Italy. Seven cellulolytic taxa were isolated and cultured to represent the pioneers in the primordial phase of cellulose colonisation. The functional diversity of fungal isolates was analysed using a phenotype microarray technique to generate a profile of their functional traits. The extent of the overlap in substrate utilisation by the various species was subsequently determined.Some of the species that acted as key cellulose decomposers are considered globally distributed airborne contaminants. Most of the cellulolytic species that were isolated during the experiment are also well known for their competitive abilities. Our study showed that at an early stage of cellulose colonisation a few fungal species with potential overlap in the overall metabolic function were able to establish themselves. The species that prevailed at the onset of cellulose colonisation did not co-occur in the field sites. A sort of "founder effect" could be hypothesised for microfungi when colonising sterile cellulose. This would suggest that scale (i.e. the spatial component) exerts a strong influence on the causative mechanisms that link genetic fungal diversity to specific ecosystem functions. (C) 2017 Elsevier GmbH. All rights reserved.

Since adequate information on the distribution of biodiversity is hardly achievable, biodiversity indicators are necessary to support the management of ecosystems. These surrogates assume that either some habitat features, or the biodiversity patterns observed in a well-known taxon, can be used as a proxy of the diversity of one or more target taxa. Nevertheless, at least for certain taxa, the validity of this assumption has not yet been sufficiently demonstrated.We investigated the effectiveness of both a habitat- and a taxa-based surrogate in six European beech forests in the Apennines. Particularly, we tested: (1) whether the stand structural complexity and the herb-layer species richness were good predictors of the fine-scale patterns of species richness of five groups of forest-dwelling organisms (beetles, saproxylic and epigeous fungi, birds and epiphytic lichens); and (2) the cross-taxon congruence in species complementarity and composition between herb-layer plants and the target taxa.We used Generalized Linear Mixed Models (GLMMs), accumulation curves and Procrustes analysis to evaluate the effectiveness of these surrogates when species richness, complementarity and composition were considered, respectively.Our results provided a limited support to the hypothesis that the herb-layer plants and the stand structural complexity were good surrogates of the target taxa. Although the richness of the herb-layer plants received a stronger support from the data than structural complexity as a predictor for the general patterns of species richness, the overall magnitude of this effect was weak and distinct taxa responded differently. For instance, for increasing levels of herb-layer richness, the richness of lichens showed a marked increase, while the richness of saproxylic fungi decreased. We also found significantly similar complementarity patterns between the herb-layer plants and beetles, as well as a significant congruence in species composition between herb-layer plants and saproxylic fungi. Finally, when different stand structural attributes were considered singularly, only the total amount of deadwood received support from the data as a predictor of the overall species richness.At the fine scale of this study, herb-layer plants and stand structural complexity did not prove to be effective surrogates of multi-taxon biodiversity in well-preserved southern European beech forests. Rather than on weak surrogates, these results suggest that sound conservation decisions should be supported by the information provided by comprehensive multi-taxonomic assessments of forest biodiversity. (C) 2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Fungi cover a range of important ecological functions associated with nutrient and carbon cycling in leaf litter and soil. As a result, research on existing relationships between fungal functional diversity, decomposition rates and competition is of key interest. Indeed, availability of nutrients in soil is largely the consequence of organic matter degradation dynamics. The Biolog® Phenotype MicroArrays™ (PM) system allows for the testing of fungi against many different carbon sources at any one time. The use and potential of the PM system as a tool for studying niche overlap and catabolic versatility of saprotrophic fungi is discussed here, and examples of its application are provided.

We suggest a method to identify the suitability of a chosen indoor environment for paper material conservation in historical libraries. Our approach is based on two steps: numerical simulation for solving the air velocity, moisture and temperature fields, and then post-processing indexes evaluation to assess how the indoor microclimatic conditions can be favourable or not to the growth and development of microorganisms responsible for paper deterioration. A real case study was analysed in two different conditions: one the present situation and the other proposed by the authors with a HVAC system assuring controlled air temperature and RH levels. Numerical models, validated by experimental data published in previous works, were used to carry out microclimatic results. Starting from these results, some indexes suggested by the scientific literature were computed to check the suitability of the indoor environment for preserving a library heritage. Boolean parameters were also deduced from the combination of microclimatic factors favouring the growth of microorganisms responsible for paper material deterioration. Our research can provide a methodological approach that predictively allows one to know when, where and how the processes responsible for indoor microorganism activity can find the microclimatic conditions for their kick-off and triggering, and then their areas of potential growth. The proposed method highlights the main causes of the deterioration processes connected to building thermo-physics. Simulation results turned out to be a fundamental approach to identify the risky zones and potential areas of triggering deterioration processes of all the materials present.

Old-growth forests are key elements of ecosystem diversity and conservation strategies, providing niche differentiation and trophic pathways that produce structural and compositional heterogeneity. In these forests, deadwood is particularly important for saproxylic and mycorrhizal fungi, sustaining forest productivity and environmental services. In this study, the saproxylic fungal diversity in Mediterranean mountain forests, characterized by different management histories and forest types (holm oak and beech), was analyzed. The relationships between saproxylic fungal biodiversity and structural attributes were considered in three forest stands of the Apennines (Italy). In addition, descriptive environmental parameters and forest traits were related to prevailing fungal communities, in order to analyze the species composition and distribution patterns of saproxylic fungi resulting from the ordination processes. The study sites were selected on the basis of their late-serial stage of development. Species frequency was analyzed through multivariate techniques to test the relationships between fungi, structural attributes and environmental variables. A Detrended Correspondence Analysis (DCA) was used to investigate the response of the overall fungal community structure to environmental gradients. Living tree volume, altitude, vegetation type, and the frequency of species with ephemeral sporocarp lifespan played a crucial role in diversifying species distribution patterns. Deadwood volume and decay classes were related to taxonomic and trophic community diversity. However, differences between the considered climatic regions exerted a major role on the occurrence of fungi with ephemeral sporocarps more than deadwood abundance, utilized primarily as fructification substrate.

The authors conducted an ecological study of forests subjected to varying management. The aim of the study was to extend and integrate, within a multivariate context, knowledge of how saproxylic fungal communities behave along altitudinal/vegetational gradients in response to the varying features and quality of coarse woody debris (CWD). The intra-annual seasonal monitoring of saproxylic fungi, based on sporocarp inventories, was used to investigate saproxylic fungi in relation to vegetation types and management categories. We analyzed fungal species occurrence, recorded according to the presence/absence and frequency of sporocarps, on the basis of the harvest season, of coarse woody debris decay classes as well as other environmental and ecological variables. Two-way cluster analysis, DCA and Spearman's rank correlations, for indirect gradient analysis, were performed to identify any patterns of seasonality and decay. Most of the species were found on CWD in an intermediate decay stage. The first DCA axis revealed the vegetational/microclimate gradient as the main driver of fungal community composition, while the second axis corresponded to a strong gradient of CWD decay classes.

β-Hexachlorocyclohexane (β-HCH) is a persistent organic pollutant (POP) of global concern with potentially toxic effects on humans and ecosystems. Fungal tolerance and biotransformation of toxic substances hold considerable promise in environmental remediation technologies as many fungi can tolerate extreme environmental conditions and possess efficient extracellular degradative enzymes with relatively non-specific activities. In this research, we have investigated the potential of a saprotrophic soil fungus, Penicillium griseofulvum Dierckx, isolated from soils with high concentrations of isomers of hexachlorocyclohexane, to biotransform β-HCH, the most recalcitrant isomer to microbial activity. The growth kinetics of the fungus were characterized after growth in stirred liquid Czapek-Dox medium. It was found that P. griseofulvum was able to grow in the presence of 1mgL−1 β-HCH and in stressful nutritional conditions at different concentrations of sucrose in the medium (0 and 5gL−1). The effects of β-HCH and the toluene, used as a solvent for β-HCH addition, on P. griseofulvum were investigated by means of a Phenotype MicroArray™ technique, which suggested the activation of certain metabolic pathways as a response to oxidative stress due to the presence of the xenobiotics. Gas chromatographic analysis of β-HCH concentration confirmed biodegradation of the isomer with a minimum value of β-HCH residual concentration of 18.6%. The formation of benzoic acid derivatives as dead-end products of β-HCH biotransformation was observed and this could arise from a possible biodegradation pathway for β-HCH with important connections to fungal secondary metabolism.