Cristian Riquelme

El Reino Fungi constituye un grupo taxonómico megadiverso cuyas múltiples funciones ecosistémicas tienen repercusiones directas sobre el bienestar y desarrollo humano. Las bases de datos de biodiversidad resuelven la fragmentación de la información, existiendo en el contexto local compendios históricos sobre hongos de Chile desarrollados previamente. En los compendios de datos referidos se observa una carencia de actualización sistemática y regular que compromete su utilidad y vigencia actual. Este trabajo presenta a mycoBaseCL como una base de datos abierta, estandarizada y actualizada que recopila todos los registros pertenecientes al reino Fungi citados para Chile. Los datos fueron obtenidos desde literatura científica (1810–2026) y listas preliminares, para luego ser validados y estructurados bajo el estándar Darwin Core. La versión 1.0 de mycoBaseCL alcanzó un total de 6546 registros (6299 a nivel de especie), lo que prácticamente duplica el número de registros reportados por las bases de datos precedentes. La información contenida resulta de especial interés para la investigación, educación, conservación y políticas públicas ambientales. La iniciativa representa la primera base de datos unificada de hongos de Chile y asume el compromiso a largo plazo de la curaduría y apertura continua de datos.

Fungal natural products, also called secondary metabolites (SMs), continue to inspire chemists and drug development. Around 30,000 fungal SMs are known, mainly from filamentous fungi of the phylum Ascomycota. Only 5% of all fungal species are described today, and even fewer have been cultured or chemically screened, which makes fungi an untapped reservoir for chemical discovery. The phylum Basidiomycota harbors chemically talented fungi such as the psilocybin producer Psilocybe cubensis (Agaricales, Hymenogastraceae), but other members like the genus Anthracophyllum (Agaricales, Omphalotaceae) remain largely genetically and chemically underexplored although new species are being discovered frequently. Here, we present the chemical and bioactivity exploration of a Chilean Anthracophyllum discolor fungus. We discovered anthracaurisin A, the first fungal nor-sesquiterpene homodimer with potent cytotoxic activity in vitro and in vivo, isolated one new and several known illudins, and established their absolute configurations.

Natural fungal polysaccharides are increasingly explored as bioactive compounds capable of orchestrating complex regenerative responses during tissue repair. This study aimed to evaluate the in vivo wound-healing efficacy and molecular mechanisms of a topical polysaccharide formulation derived from Bovistella utriformis (Calvatin 2%) using complementary murine, zebrafish, and proteomic approaches. Phylogenetic analysis based on ITS sequences confirmed the taxonomic identity of the Chilean specimen. In a murine full-thickness excisional wound model, Calvatin 2% significantly accelerated wound contraction and re-epithelialization compared to both saline and base-cream controls, achieving near-complete closure by day 10. Label-free quantitative proteomic analysis of wound tissue by UHPLC-HRMS identified 2432 high-confidence proteins, with 171 upregulated and 153 downregulated proteins in the Calvatin versus control comparison (p < 0.01). Functional enrichment revealed strong activation of innate immune response, complement activation, coagulation cascades, and acute-phase response pathways, while lipid metabolism, mitochondrial energy production, and muscle-related processes were significantly downregulated. KEGG pathway analysis further highlighted complement and coagulation cascades and neutrophil extracellular trap formation as the most prominently affected pathways. In a zebrafish laser-induced wound model, Calvatin induced early and sustained regenerative responses, reaching over 93% wound closure by 18 days post-lesion, significantly outperforming both PBS and vehicle-treated groups. Chronic oral administration of polysaccharides did not induce major hepatic inflammatory responses, supporting systemic safety. Overall, these findings indicate that B. utriformis polysaccharides are associated with modulation of immune- and repair-related pathways together with tissue reprogramming processes that may contribute to accelerated cutaneous regeneration, positioning Calvatin as a promising bioactive formulation for wound-healing applications.

This study analyzes the impact of iNaturalist on the recording and documentation of fungi in Chile from 2008 to 2024, highlighting its role in integrating citizen science into biodiversity monitoring. This community effort—which currently totals more than 63,000 observations representing 1,245 species—is concentrated in the central and southern regions of the country, mainly in urban areas, where a small group of hyperprolific users generates 44.40% of the records. Since 2020, an increase in the number of observations has been observed, which may be linked to a growing interest in mycology. The use of iNaturalist allows overcoming traditional logistical limitations, expanding the taxonomic, spatial, and temporal coverage of fungal observations, but these advantages are not without biases. In addition, mycology in Chile faces structural challenges, such as funding and training of new specialists. Collaboration between amateurs and professional mycologists is essential to validate the data and extract the potential of this type of tools. This approach complements conventional methods of biodiversity studies and strengthens conservation policies. Although iNaturalist has proven to be an effective tool, more effort and resources are required to address the knowledge gaps of fungal biodiversity. This study reinforces the potential of citizen science as a source of valuable and potentially useful data to address the planetary biodiversity crisis.

Este estudio analiza el impacto de iNaturalist en el registro y documentación de hongos en Chile desde 2008 hasta 2024, destacando su rol en la integración de la ciencia ciudadana al monitoreo de biodiversidad. Este esfuerzo comunitario —que actualmente suma más de 63000 observaciones que representan 1245 especies— se concentra en las regiones centro y sur del país, principalmente en áreas urbanas, donde un reducido grupo de usuarios hiperprolíficos genera el 44,40 % de los registros. Desde 2020, se ha observado un aumento en el número de observaciones, que puede estar ligado a un creciente interés en la micología. El uso de iNaturalist permite superar las limitaciones logísticas tradicionales, ampliando la cobertura taxonómica, espacial y temporal de las observaciones de hongos, pero estas ventajas no están exentas de sesgos. Además, la micología en Chile enfrenta desafíos estructurales, como el financiamiento y la formación de nuevos especialistas. La colaboración entre aficionados y micólogos profesionales es fundamental para validar los datos y extraer el potencial de este tipo de herramientas. Este enfoque complementa los métodos convencionales de los estudios de biodiversidad y fortalece las políticas de conservación. Aunque iNaturalist ha demostrado ser una herramienta efectiva, se requieren más esfuerzos y recursos para abordar los vacíos de conocimiento de la biodiversidad fúngica. Este estudio refuerza el potencial de la ciencia ciudadana como fuente de datos valiosos y potencialmente útiles para hacer frente a la crisis ambiental.

Fomitiporia species have aroused the interest of numerous investigations that reveal their biological activity and medicinal potential. The present investigation shows the antioxidant, anticancer, and immunomodulatory activity of acidic polysaccharides obtained from the fungus Fomitiporia chilensis. The acidic polysaccharides were obtained for acidic precipitation with 2% O-N-cetylpyridinium bromide. Chemical analysis was performed using FT-IR and GC-MS methods. The antioxidant capacity of acidic polysaccharides from F. chilensis was evaluated by scavenging free radicals with an ABTS assay. Macrophage proliferation and cytokine production assays were used to determine the immunomodulatory capacity of the polysaccharides. Anti-tumor and cytotoxicity activity was evaluated with an MTT assay in the U-937, HTC-116, and HGF-1 cell lines. The effect of polysaccharides on the cell cycle of the HCT-116 cell line was determined for flow cytometry. Fourier Transform-infrared characterization revealed characteristic absorption peaks for polysaccharides, whereas the GC-MS analysis detected three peaks corresponding to D-galactose, galacturonic acid, and D-glucose. The secreted TNF-α concentration was increased when the cell was treated with 2 mg mL⁻¹ polysaccharides, whereas the IL-6 concentration was increased with all of the evaluated polysaccharide concentrations. A cell cycle analysis of HTC-116 treated with polysaccharides evidenced that the acidic polysaccharides from F. chilensis induce an increase in the G0/G1 cell cycle phase, increasing the apoptotic cell percentage. Results from a proteomic analysis suggest that some of the molecular mechanisms involved in their antioxidant and cellular detoxifying effects and justify their traditional use in heart diseases. Proteomic data are available through ProteomeXchange under identifier PXD048361. The study on acidic polysaccharides from F. chilensis has unveiled their diverse biological activities, including antioxidant, anticancer, and immunomodulatory effects. These findings underscore the promising therapeutic applications of acidic polysaccharides from F. chilensis, warranting further pharmaceutical and medicinal research exploration.

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.

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. Graphical Abstract

Un catálogo o checklist recopila la información conocida sobre un grupo taxonómico particular en una región específica. La contrastación de las fuentes utilizadas y la definición de los criterios empleados para la elaboración del catastro hacen del resultado final un material útil para la toma de decisiones sobre conservación de la biodiversidad. Los hongos afiloforoides (Basidiomycota, Agaricomycotina) son una categoría artificial que incluye principalmente a los políporos, corticioides y clavarioides. Tradicionalmente la taxonomía, sistemática y biogeografía del grupo a nivel local ha sido escasamente tratada. Este trabajo presenta datos actualizados sobre 16 especies de hongos afiloforoides de Chile, incorporando nuevos registros, nuevas localidades y nuevos datos sobre la ecología del grupo. A su vez, agrega nueva información sobre especies recientemente descritas. La realización de inventarios de especies y el monitoreo constante de los nuevos datos generados sobre un grupo taxonómico determinado, además del valor de las colecciones biológicas juegan un rol de extrema relevancia en la conservación de la biodiversidad.