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Fungi have a unique metabolic plasticity allowing them to produce a wide range of natural products. Since the discovery of penicillin, an antibiotic of fungal origin, substantial efforts have been devoted globally to search for fungal-derived natural bioactive products. Andean region forests represent one of the few undisturbed ecosystems in the world with little human intervention. While these forests display a rich biological diversity, mycological and chemical studies in these environments have been scarce. This review aims to summarise all the efforts regarding the chemical or bioactivity analyses of Agaricomycetes (Basidiomycota) from southern South America environments. Overall, herein we report a total of 147 fungal species, 21 of them showing chemical characterisation and/or biological activity. In terms of chemical cores, furans, chlorinated phenol derivatives, polyenes, lactones, terpenes and himanimides have been reported. These natural products displayed a range of biological activities including antioxidant, antimicrobial, antifungal, neuroprotective and osteoclast-forming suppressing effects. [ABSTRACT FROM AUTHOR]

A new and threatened polypore species, Bondarzewia loguerciae, is described from the cloud forests of southern Brazil. It is characterized by single-pileate basidiomata that grow on dead branches and along living stems of standing trunks and present a context with dark lines and resinous tubes. When growing in axenic culture, this species also develops chlamydospores. We provide an illustrated morphological description and molecular analysis. Our specimens from Brazil form a monophyletic group among other species of the Southern Hemisphere. The conservation status of B. loguerciae is assessed and published as "Critically Endangered" based on the International Union for Conservation of Nature (IUCN) criteria. Additionally, a key to the species is provided. [ABSTRACT FROM AUTHOR]

Fungal polysaccharides possess a broad biological activity, including cytotoxic and antioxidant activities. This work aimed to evaluate the cytotoxic and antioxidant activity of the acidic polysaccharides of Phylloporia boldo strain (named PBAP40). Cytotoxic activity of polysaccharide was evaluated determining the viability of three tumor cell lines by MTT assay. The effect of acidic polysaccharide on the cell cycle of HL-60 cell line was evaluated by flow cytometry, and the antioxidant activity was determined by DPPH and ABTS assays. PBAP40 showed cytotoxic effects in tumor cell lines. Results suggest that P. boldo acidic polysaccharides arrested tumor cells in the cell cycle Sub G1 phase. The acidic polysaccharides of PBAP40 strain were not cytotoxic for the non-tumor cell line. PBAP40 also showed excellent antioxidant activity. The FT-IR analysis of the acidic polysaccharides indicated the presence of glucans bearing α-and β- type glycosidic bonds. [ABSTRACT FROM AUTHOR]

Global forests are increasingly being threatened by altered climatic conditions and increased attacks by pests and pathogens. The complex ecological interactions among pathogens, microbial communities, tree hosts and the environment are important drivers of forest dynamics. Little is known about the ecology of forest pathology and related microbial communities in temperate forests of the southern hemisphere. In this study, we used next‐generation sequencing to characterize sapwood‐inhabiting fungal communities in North Patagonian Nothofagus forests and assessed patterns of diversity of taxa and ecological guilds across climatic, site and host variables (health condition and compartment) as a contribution to Nothofagus autecology. The diversity patterns inferred through the metabarcoding analysis were similar to those obtained through culture‐dependent approaches. However, we detected additional heterogeneity and greater richness with culture‐free methods. Host species was the strongest driver of fungal community structure and composition, while host health status was the weakest. The relative impacts of site, season, plant compartment and health status were different for each tree species; these differences can be interpreted as a matter of water availability. For Nothofagus dombeyi, which is distributed across a wide range of climatic conditions, site was the strongest driver of community composition. The microbiome of N. pumilio varied more with season and temperature, a relevant factor for forest conservation in the present climate change scenario. Both species carry a number of potential fungal pathogens in their sapwood, whether they exhibit symptoms or not. Our results provide insight into the diversity of fungi associated with the complex pathobiome of the dominant Nothofagus species in southern South America. [ABSTRACT FROM AUTHOR]

In the temperate forests of Patagonia, Argentina, Nothofagus dombeyi , commonly known as Coihue, has shown sensitivity to intense drought events, leading to mortality. Studies have been conducted on Coihue decline and mortality using a variety of approaches, including the role of extreme heat waves and drought, pests and pathogens, particularly the fungus Huntiella decorticans. This work aimed to evaluate survival, vitality, necrosis extension and growth response of inoculated and non-inoculated Coihue seedlings from different provenances exposed to different soil moisture levels. To achieve this goal, 96 Coihue seedlings from 2 different provenances were assigned to 8 different experimental treatments. Treatments were composed of the presence or absence of H. decorticans and different soil moisture content conditions, dry, wet and the exposure to dry condition at different times of the experiment. Both dry conditions and H. decorticans had negative effects on the survival and growth rate of Coihue. The combination of both factors resulted in 100 % mortality, regardless of the plants' geographical provenances. Mortality began to be observed 3 months after pathogen inoculation, during the warmest month. Necrosis extension produced by the pathogen was similar for most of the inoculated treatments. The treatment under wet condition during the experiment but subjected to dry condition in the previous growing season presented lower necrosis extension (8.4 ± 3.2 %), than the other treatments. The radial increase was also affected by the treatments and geographical provenance, being those plants exposed to dry conditions which grew less (0.19 ± 0.21 mm). This study enhances our understanding of the plant–pathogen interaction. According to our results, Coihue may become more susceptible to mortality, when H. decorticans and water deficit conditions act synergistically. [ABSTRACT FROM AUTHOR]

Acanthocorticium brueggemannii gen. et sp. nov. is introduced based on specimens from Southern Brazil. This corticioid fungus is characterized by resupinate basidiomes with smooth to tuberculate hymenophore, a monomitic hyphal system with simple-septate hyphae, finely echinulate halocystidia, cylindrical to clavate, dextrinoid acanthophyses, and globose, hyaline, smooth, and thin-walled IKI- basidiospores. Phylogenetic analyses of a LSU data set and a combined data set of ITS and LSU were carried out and the new taxon was found to be related to cyphelloid fungi within the Agaricales. Descriptions and drawings of the microscopic features ofA. brueggemannii are provided. Keywords: acanthophyses, Aphyllophorales, Corticiaceae s.l., Cyphellaceae, Henningsomyces, Rectipilus. Acanthocorticium brueggemannii gen. et sp. nov. est introduit a partir de specimens du Bresil du Sud. Ce fongus est caracterise par des basidiomes resupines avec des hymenophores lisses a tubercules, un systeme d'hyphes monomitique avec d'hyphes generatrices a cloisons simples, halocystides a parois finement echinules, acantophyses dextrinoides cilindriques a clavees, et basidiospores globoses, hyalins, lisses et a paroi mince, IKI-. Les analyses phylogenetiques d'un ensemble de donnees de LSU et d'un ensemble de donnees combinee d'ITS et LSU ont ete effectuees et le nouveau taxon fut recupere et liee aux champignons cyphelles dans les Agaricales. On present les descriptions du nouveau genre et la nouvelle espece, ainsi que des dessins et caracteristiques microscopiques de A. brueggemannii. Mots-cles : acanthophyses, Aphyllophorales, Corticiaceae s.l., Cyphellaceae, Henningsomyces, Rectipilus., Introduction Corticioid fungi, also called Corticiaceae s.l., are defined as non-poroid homobasidiomycetes that usually develop effused, resupinate basidiomes with smooth hymenophores on wood, but several variations of this concept are [...]