Typification of the name Arthopyreniaparolinii Beltr. (Ascomycota, Dothideomycetes, Pleosporales, Arthopyreniaceae)

Arthopyreniaparolinii Beltr. is one of the few species of the lichen genus Arthopyrenia A. Massal. described by Italian authors of the XIX century, lacking type formal association. In this regard, the name Arthopyreniaparolinii is hereby lectotypified using a specimen stored in the lichen herbarium of A.B. Massalongo at VER. Additional original material was found only at M, while another specimen at MSNVE, labelled as Spermatodiumparolinii, although referable to this species, should not be considered as original material. Arthopyreniaparolinii is among the least well-known species in the genus. Given the genus Arthopyrenia is still very poorly known, it is important to clarify the original material of the species and propose the lectotyping. The selected lectotype is the only sample among the analyzed ones reporting complete data on the locus classicus; it conforms to the characters described in the protologue and comes from the Herbarium Beltramini.

Variation in monthly and seasonal elevation use impacts behavioral and dietary flexibility in Rhinopithecus bieti

Black-and-white snub-nosed monkeys (Rhinopithecus bieti) rely on behavioral and dietary flexibility to survive in temperate latitudes at high-elevation habitats characterized by climate and resource seasonality. However, little is known about how elevation influences their behavioral and dietary flexibility at monthly or seasonal scales. We studied an isolated R. bieti population at Mt. Lasha in the Yunling Provincial Nature Reserve, Yunnan, China, between May 2008 and August 2016 to assess the impacts of elevation on feeding behavior and diet. Across our sample, R. bieti occupied elevations between 3031 and 3637 m above mean sea level (amsl), with a 315.1 m amsl range across months and a 247.3 m amsl range across seasons. Contrary to expectations, individuals spent less time feeding when ranging across higher elevations. Lichen consumption correlated with elevation use across months and seasons, with individuals spending more time feeding on this important resource at higher elevations. Leaf consumption only correlated with elevation use during the spring. Our results suggest that R. bieti do not maximize their food intake at higher elevations and that monthly and seasonal changes in lichen and leaf consumption largely explain variation in elevation use. These findings shed light on the responses of R. bieti to environmental change and offer insight into strategies for conserving their habitats in the face of anthropogenic disturbance.

Suisho, Japan

We report 16S rRNA gene amplicon data for the microbiomes in selected alpine plants (genera Artemisia, Parnassia, and Phyllodoce) and lichens (genera Cladonia and a mixture of Miriquidica and Rhizocarpon) from Mt. Suisho, Japan. Most of these samples were dominated by Pseudomonadota, while some contained the rarely cultivated phylum Vulcanimicrobiota (Candidatus Eremiobacterota/WPS-2).

Environmental drivers and cryptic biodiversity hotspots define endophytes in Earth's largest terrestrial biome

Understanding how symbiotic associations differ across environmental gradients is key to predicting the fate of symbioses as environments change, and it is vital for detecting global reservoirs of symbiont biodiversity in a changing world.1,2,3 However, sampling of symbiotic partners at the full-biome scale is difficult and rare. As Earth's largest terrestrial biome, boreal forests influence carbon dynamics and climate regulation at a planetary scale. Plants and lichens in this biome host the highest known phylogenetic diversity of fungal endophytes, which occur within healthy photosynthetic tissues and can influence hosts' resilience to stress.4,5 We examined how communities of endophytes are structured across the climate gradient of the boreal biome, focusing on the dominant plant and lichen species occurring across the entire south-to-north span of the boreal zone in eastern North America. Although often invoked for understanding the distribution of biodiversity, neither a latitudinal gradient nor mid-domain effect5,6,7 can explain variation in endophyte diversity at this trans-biome scale. Instead, analyses considering shifts in forest characteristics, Picea biomass and age, and nutrients in host tissues from 46° to 58° N reveal strong and distinctive signatures of climate in defining endophyte assemblages in each host lineage. Host breadth of endophytes varies with climate factors, and biodiversity hotspots can be identified at plant-community transitions across the boreal zone at a global scale. Placed against a backdrop of global circumboreal sampling,4 our study reveals the sensitivity of endophytic fungi, their reservoirs of biodiversity, and their important symbiotic associations, to climate.

Interactions of moisture and light drive lichen growth and the response to climate change scenarios - experimental evidence for Lobaria pulmonaria

BACKGROUND AND AIMS

There is growing interest in the functional ecology of poikilohydric nonvascular photoautotrophs (NVPs), including 'cryptogamic' bryophytes and lichens. These organisms are structurally important in many ecosystems, contributing substantially to ecosystem function and services, while also being sensitive to climate change. Previous research has quantified the climate change response of poikilohydric NVPs using predictive bioclimatic models with standard climate variables including precipitation totals and temperature averages. This study aimed for an improved functional understanding of their climate change response based on their growth rate sensitivity to moisture and light.

METHODS

We conducted a 24-month experiment to monitor lichen hydration and growth. We accounted for two well-known features in the ecology of poikilohydric NVPs, and exemplified here for a structurally dominant lichen epiphyte, Lobaria pulmonaria: (i) sensitivity to multiple sources of atmospheric moisture including rain, condensed dew-formation and water vapour, and (ii) growth determined by the amount of time hydrated in the light, driving photosynthesis, referred to as the Iwet hypothesis.

KEY RESULTS

First, we found that even within an oceanic high-rainfall environment, lichen hydration was better explained by vapour pressure deficit (VPD) than precipitation totals. Second, growth at a monthly resolution was positively related to the amount of time spent hydrated in the light, and negatively related to the amount of time spent hydrated in the dark.

CONCLUSIONS

Using multimodel averaging to project growth models for an ensemble of future climate change scenarios, we demonstrated reduced net growth for L. pulmonaria by the late 21st Century, explained by extended climate dryness and lichen desiccation for periods when there is otherwise sufficient light to drive photosynthesis. The results further emphasise a key issue of photoperiodism when constructing functionally relevant models to understand the risk of climate change, especially for poikilohydric NVPs.

Remote sensing and spectroscopy of lichens

Lichens are combinations of two symbiotic organisms, a green alga or cyanobacterium and a fungus. They grow in nearly all terrestrial ecosystems and survive in habitats, which are very dry or cold, or too poor in nutrients to maintain vegetation growth. Because lichens grow on visible surfaces and exhibit spectral properties, which are clearly different from, for example, vegetation, it is possible to distinguish them in remote sensing data. In this first systematic review article on remote sensing of lichens, we analyze and summarize which lichen species or genera, and in which habitats and geographical regions, have been remotely sensed, and which remote sensing or spectroscopic technologies have been used. We found that laboratory or in situ measured spectra of over 70 lichen species have been reported to date. We show that studies on remote sensing of lichens fall under seven broad themes: (1) collection of lichen spectra for quantification of lichen species or characteristics, (2) pollution monitoring with lichens as ecological indicators, (3) geological and lithological mapping, (4) desert and dryland monitoring, (5) animal habitat monitoring, (6) land cover or vegetation mapping, and (7) surface energy budget modeling.

Monitoring of Antarctica's Fragile Vegetation Using Drone-Based Remote Sensing, Multispectral Imagery and AI

Vegetation in East Antarctica, such as moss and lichen, vulnerable to the effects of climate change and ozone depletion, requires robust non-invasive methods to monitor its health condition. Despite the increasing use of unmanned aerial vehicles (UAVs) to acquire high-resolution data for vegetation analysis in Antarctic regions through artificial intelligence (AI) techniques, the use of multispectral imagery and deep learning (DL) is quite limited. This study addresses this gap with two pivotal contributions: (1) it underscores the potential of deep learning (DL) in a field with notably limited implementations for these datasets; and (2) it introduces an innovative workflow that compares the performance between two supervised machine learning (ML) classifiers: Extreme Gradient Boosting (XGBoost) and U-Net. The proposed workflow is validated by detecting and mapping moss and lichen using data collected in the highly biodiverse Antarctic Specially Protected Area (ASPA) 135, situated near Casey Station, between January and February 2023. The implemented ML models were trained against five classes: Healthy Moss, Stressed Moss, Moribund Moss, Lichen, and Non-vegetated. In the development of the U-Net model, two methods were applied: Method (1) which utilised the original labelled data as those used for XGBoost; and Method (2) which incorporated XGBoost predictions as additional input to that version of U-Net. Results indicate that XGBoost demonstrated robust performance, exceeding 85% in key metrics such as precision, recall, and F1-score. The workflow suggested enhanced accuracy in the classification outputs for U-Net, as Method 2 demonstrated a substantial increase in precision, recall and F1-score compared to Method 1, with notable improvements such as precision for Healthy Moss (Method 2: 94% vs. Method 1: 74%) and recall for Stressed Moss (Method 2: 86% vs. Method 1: 69%). These findings contribute to advancing non-invasive monitoring techniques for the delicate Antarctic ecosystems, showcasing the potential of UAVs, high-resolution multispectral imagery, and ML models in remote sensing applications.

Choisy": Identification by LC-MS/MS peptide mass fingerprinting

Parmotrema perlatum, a lichen belonging to the family Parmeliaceae, is well known for its culinary benefits and aroma used as a condiment in Indian homes is also known as the "black stone flower" or "kalpasi" in India. This research intends to analyze the antioxidant power of the crude extracts using four pH-based buffers solubilized proteins/peptides and RP-HPLC fractions of P. perlatum obtained by purification. The proteins that were extracted from the four different buffers were examined using LC-MS/MS-based peptide mass fingerprinting. When compared to the other buffers, the 0.1 M of Tris-HCl buffer pH 8.0 solubilized proteins/peptides had the strongest antioxidant capacity. The sequential purification of the peptide was carried out by using a 3-kDa cut-off membrane filter and semipreparative RP-HPLC. Additionally, the purified fractions of the peptide's antioxidant activity were assessed, and effects were compared with those of the crude and 3 kDa cut--off membrane filtrates. The peptide fractions were sequenced by LC-MS/MS, which reveals that fraction 2 from RP-HPLC with the sequence LSWFMVVAP has shown the highest antioxidant potential in comparison with other fractions which can serve as the potential natural antioxidant drug. Further, fraction 2 also showed antibacterial activity against the selected microorganisms.

nov., a new lichen-derived rare actinobacterium exhibiting antimicrobial and anticancer activity

A novel lichen-derived actinobacterium, designated Pm04-4T, was isolated from Pyxine cocoes (Sw.) Nyl. lichen collected from Chaiyaphum, Thailand. A polyphasic approach was used to describe the taxonomic position of the strain. The strain had morphological and chemotaxonomic properties similar to members of the genus Actinoplanes. It produced sporangia on the substrate mycelia. Meso-diaminopimelic acid, galactose, glucose and mannose were detected in the whole-cell hydrolysate of the strain. The major menaquinone was MK-9(H4). The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannoside. The predominant cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. Strain Pm04-4T showed the highest 16S rRNA gene sequence similarity to Actinoplanes akusuensis TRM 8003T (99.0 %). In the phylogenomic tree, strain Pm04-4T was positioned close to A. aksuensis TRM88003T, A. maris M416T, A. polyasparticus TRM66264T, A. hotanensis TRM88002T, A. abujensis DSM 45518T, A. bogorensis NBRC 110975T, A. brasiliensis DSM 43805T, A. lichenicola LDG1-01T and A. ovalisporus LDG1-06T. The average nucleotide identity and digital DNA-DNA hybridization values between strain Pm04-4T and its closely related neighbours were below the threshold values for describing new species. Moreover, the strain could be distinguished from its closely related type strains by phenotypic properties. Based on genotypic and phenotypic evidence, it can be concluded that strain Pm04-4T is a representative of a new Actinoplanes species for which the name Actinoplanes pyxinae sp. nov. is proposed. The type strain is Pm04-4T (=TBRC 16207T=NBRC 115836T). The type strain exhibited activity against Staphylococcus aureus ATCC 25923 as well as four yeast strains, namely Candida albicans TISTR 5554, Candida glabrata TISTR 5006, Candida krusei TISTR 5351 and Candida parapsilosis TISTR 5007. It also showed cytotoxicity against Caco-2, MNT-1 and MCF-7 cancer cells.

Synthesis of 2,8-Dioxabicyclo[3.3.1]nonane Derivatives and Their Neuroprotective Activities

Twenty natural-product-like 2,8-dioxabicyclo[3.3.1]nonane derivatives were synthesized and their neuroprotective activities were tested using human monoamine oxidases (MAO) A and B and acetyl and butyryl cholinesterases (ChE). Compound 1s showed inhibitory activity for MAO-A, MAO-B and acetylcholinesterase (AChE) (IC50 values 34.0, 2.3 and 11.0 µM, respectively). The inhibition mode of (-)-1s for MAO-B was investigated. Chiral HPLC of (±)-1s separated the enantiomers and (-)-1s showed MAO-B inhibitory activity. Molecular docking simulation of (-)-1s and MAO-B revealed the binding mode.

Pleiotropic Potential of Evernia prunastri Extracts and Their Main Compounds Evernic Acid and Atranorin: In Vitro and In Silico Studies

Evernia prunastri is a lichen widely distributed in the Northern Hemisphere. Its biological properties still need to be discovered. Therefore, our paper focuses on studies of E. prunastri extracts, including its main metabolites evernic acid (EA) or atranorin (ATR). Phytochemical profiles using chromatographic analysis were confirmed. The antioxidant activity was evaluated using in vitro chemical tests and in vitro enzymatic cells-free tests, namely superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT). The anti-inflammatory potential using cyclooxygenase-2 (COX-2) and hyaluronidase were determined. The neuroprotective potential using acetylcholinesterase, (AChE), butyrylcholinesterase (BChE), and tyrosinase (Tyr) was estimated. The hypoglycemic activity was also confirmed (α-glucosidase). Principal component analysis was performed to determine the relationship between the biological activity of extracts. The inhibitory effect of EA and ATR on COX-2 AChE, BChE, Tyr, and α-glucosidase was evaluated using molecular docking techniques and confirmed for EA and ATR (besides α-glucosidase). The penetration of EA and ATR from extracts through the blood-brain barrier was confirmed using the parallel artificial membrane permeability assay blood-brain barrier test. In conclusion, depending on chemical surroundings and the concentration, the E. prunastri extracts, EA or ATR, showed attractive pleiotropic properties, which should be further investigated.

The phylogeny and taxonomy of Upretia (Caloplacoideae, Teloschistaceae), reveal three new species from Southwestern China

Several specimens of Upretia from Southwest China are morphologically and phylogenetically distinct from currently recognized species in the genus. These specimens are here accommodated within a new species, Upretiazeorina Li J. Li & Printzen. It is characterized by an areolate to squamulose thallus with brown to blackish brown upper surface, pruinose, zeorine type apothecia, black discs, narrowly bacilliform conidia, and the production of gyrophoric acid. Two other specimens of Upretia from China are distinct from currently accepted species and tentatively referred to as Upretia sp. 1 and Upretia sp. 2. A key to all known species of Upretia is also provided.

In Vitro and in Silico Studies of Lichen Compounds Atranorin and Salazinic Acid as Potential Antioxidant, Antibacterial and Anticancer Agents

Lichens are symbiotic organisms made up of alga/cyanobacterium and fungus. We investigated antioxidant, antibacterial and anticancer properties of two lichen compounds, atranorin and salazinic acid, and five lichen species: Heterodermia boryi, Heterodermia diademata, Heterodermia hypocaesia, Parmotrema reticulatum, and Stereocaulon foliolosum. Free radical scavenging, Ferric reducing potential, Nitric oxide scavenging, and Trolox equivalent capacity were used to measure antioxidant activity. Strong radical scavenging action was demonstrated by atranorin and salazinic acid, with IC50 values of 39.31 μM and 12.14 μM, respectively. The Minimum Inhibitory Concentration (MIC) assay based on resazurin, was used to measure antibacterial activity. Parmotrema reticulatum demonstrated significant antibacterial activity against Raoultella planticola with MIC of 7.8 μg/mL. Cytotoxicity assay on breast cancer cell line was used to assess anticancer activity. To further understand the binding locations on the target proteins Er (Estrogen Receptor alpha), EGFR (Epidermal Growth Factor Receptor), mTOR (Mammalian Target of Rapamycin), and PgR (Progesterone Receptor), molecular docking experiments were conducted. Docking study showed that the binding energies of atranorin and salazinic acid with mTOR were -5.31 kcal/mol and -3.43 kcal/mol, respectively. The results suggest that atranorin has the potential to be a multitargeted molecule with natural antioxidant, antibacterial, and anticancer properties.

Lichen-associated microbial members are prevalent in the snow microbiome of a sub-arctic alpine tundra

Snow is the largest component of the cryosphere, with its cover and distribution rapidly decreasing over the last decade due to climate warming. It is imperative to characterize the snow (nival) microbial communities to better understand the role of microorganisms inhabiting these rapidly changing environments. Here, we investigated the core nival microbiome, the cultivable microbial members, and the microbial functional diversity of the remote Uapishka mountain range, a massif of alpine sub-arctic tundra and boreal forest. Snow samples were taken over a two-month interval along an altitude gradient with varying degree of anthropogenic traffic and vegetation cover. The core snow alpine tundra/boreal microbiome, which was present across all samples, constituted of Acetobacterales, Rhizobiales and Acidobacteriales bacterial orders, and of Mycosphaerellales and Lecanorales fungal orders, with the dominant fungal taxa being associated with lichens. The snow samples had low active functional diversity, with Richness values ranging from 0 to 19.5. The culture-based viable microbial enumeration ranged from 0 to 8.05 × 103 CFUs/mL. We isolated and whole-genome sequenced five microorganisms which included three fungi, one alga, and one potentially novel bacterium of the Lichenihabitans genus; all of which appear to be part of lichen-associated taxonomic clades.

Fungal-Algal Association Drives Lichens' Mutualistic Symbiosis: A Case Study with Trebouxia-Related Lichens

Biotic and abiotic factors influence the formation of fungal-algal pairings in lichen symbiosis. However, the specific determinants of these associations, particularly when distantly related fungi are involved, remain poorly understood. In this study, we investigated the impact of different drivers on the association patterns between taxonomically diverse lichenized fungi and their trebouxioid symbiotic partners. We collected 200 samples from four biomes and identified 41 species of lichenized fungi, associating them with 16 species of trebouxioid green algae, of which 62% were previously unreported. The species identity of both the fungal and algal partners had the most significant effect on the outcome of the symbiosis, compared to abiotic factors like climatic variables and geographic distance. Some obviously specific associations were observed in the temperate zone; however, the nestedness value was lower in arid regions than in cold, polar, and temperate regions according to interaction network analysis. Cophylogenetic analyses revealed congruent phylogenies between trebouxioid algae and associated fungi, indicating a tendency to reject random associations. The main evolutionary mechanisms contributing to the observed phylogenetic patterns were "loss" and "failure to diverge" of the algal partners. This study broadens our knowledge of fungal-algal symbiotic patterns in view of Trebouxia-associated fungi.

Phylogeny, morphology and chemistry reveal two new multispored species in the Lecanorasubfusca group (Lecanoraceae, Ascomycota)

Two new multispored species from China, Lecanoraanhuiensis Li J. Li & Printzen, sp. nov. and Lecanorapseudojaponica Li J. Li & Printzen, sp. nov. are described and illustrated here, based on morphological, chemical and molecular evidence. Lecanoraanhuiensis is characterised by an epruinose, yellowish-brown to deep brown apothecial disc, an epihymenium with fine crystals, an amphithecium with small crystals, 16-spored asci and the presence of zeorin, in addition to atranorin. Lecanorapseudojaponica is characterised by an epruinose, red-brown apothecial disc, an epihymenium without crystals, an amphithecium with small crystals, 8 or 16- spored asci and the presence of zeorin and the stictic acid complex, in addition to atranorin. Phylogenetic reconstructions, based on mtSSU, nrITS and nrLSU suggest that these two species are members of the Lecanorasubfusca group. They are compared with morphologically similar and phylogenetically related species, based on a nrITS dataset. Phylogenetic results show that the multispored taxa of Lecanora are polyphyletic. The number of ascospores per ascus appears to be a taxonomic character of minor importance. Detailed descriptions, discussions and figures for the two new species from China and a key for the multispored species of Lecanora worldwide are provided.

In Vitro Anthelminthic Activity and Ultrastructural Analysis of Barbatic Acid against Schistosomulae and Juvenile Worms of Schistosoma mansoni

Schistosomiasis affects about 260 million people worldwide and the search for new schistosomicidal compounds is urgent. In this study we evaluated the in vitro effect of barbatic acid against schistosomulae and young worms of Schistosoma mansoni. The barbatic acid was evaluated through the bioassay of motility and mortality, cellular viability and ultrastructural analysis of juvenile stages through Scanning Electron Microscopy. Barbatic acid showed a schistosomicidal effect against schistosomulae and young worms of S. mansoni after 3 h of exposure. At the end of 24 h, barbatic acid showed 100 %, 89.5 %, 52 % and 28.5 % of lethality for schistosomulae at the concentrations of 200, 100, 50 and 25 μM, respectively. For young worms, barbatic acid showed 100 % and 31.7 % of lethality at the concentrations of 200 and 100 μM, respectively. Motility changes were observed at all sublethal concentrations. There was a significant reduction in the viability of young worms after exposure to barbatic acid at 50, 100 and 200 μM. Extensive damage to the schistosomulae and young worm's tegument, was observed from 50 μM. This report provides data showing the schistosomicidal effect of barbatic acid on schistosomulae and young worms of S. mansoni, causing death, motility changes and ultrastructural damage to worms.

Topography of UV-Melanized Thalli of Lobaria pulmonaria (L.) Hoffm

Lichens are unique extremophilic organisms due to their phenomenal resistance to adverse environmental factors, including ultraviolet (UV) irradiation. Melanization plays a special role in the protection of lichens from UV-B stress. In the present study, we analyzed the binding of melanins with the components of cell walls of the mycobiont of the upper cortex in the melanized lichen thalli Lobaria pulmonaria. Using scanning electron and atomic force microscopy, the morphological and nanomechanical characteristics of the melanized layer of mycobiont cells were visualized. Melanization of lichen thalli led to the smoothing of the surface relief and thickening of mycobiont cell walls, as well as the reduction in adhesion properties of the lichen thallus. Treatment of thalli with hydrolytic enzymes, especially chitinase and lichenase, enhanced the yield of melanin from melanized thalli and promoted the release of carbohydrates, while treatment with pectinase increased the release of carbohydrates and phenols. Our results suggest that melanin can firmly bind with hyphal cell wall carbohydrates, particularly chitin and 1,4-β-glucans, strengthening the melanized upper cortex of lichen thalli, and thereby it can contribute to lichen survival under UV stress.

Comparative Evaluation of Antioxidant Status and Mineral Composition of Diploschistes ocellatus, Calvatia candida (rostk.) Hollós, Battarrea phalloides and Artemisia lerchiana in Conditions of High Soil Salinity

Natural reserves play a fundamental role in maintaining flora and fauna biodiversity, but the biochemical characteristics of such ecosystems have been studied in an extremely fragmentary way. For the first time, mineral composition and antioxidant status of three systematic groups of organisms, lichens (Diplischistes ocellatus), mushrooms (Calvatia candida and Battarrea phalloides) and wormwood (Artemisia lerchiana) have been described at the territory of Bogdinsko-Baskunchak Nature Reserve (Astrakhan region, Russia), characterized by high salinity and solar radiation, and water deficiency. Through ICP-MS, it was determined that scale lichen D. ocellatus accumulated up to 10-15% Ca, 0.5% Fe, 15 mg kg^-1 d.w. iodine (I), 54.5 mg kg^-1 Cr. Battarrea phalloides demonstrated anomalously high concentrations of B, Cu, Fe, Mn Se, Zn, Sr and low Na levels, contrary to Calvatia candida mushrooms accumulating up to 10,850 mg kg^-1 Na and only 3 mg kg^-1 Sr. The peculiarity of A. lerchiana plants was the high accumulation of B (22.23 mg kg^-1 d.w.), Mn (57.48 mg kg^-1 d.w.), and antioxidants (total antioxidant activity: 68.6 mg GAE g^-1 d.w.; polyphenols: 21.0 mg GAE g^-1 d.w.; and proline: 5.45 mg g^-1 d.w.). Diploschistes ocellatus and Calvatia candida demonstrated the lowest antioxidant status: 3.6-3.8 mg GAE g^-1 d.w. total antioxidant activity, 1.73-2.10 mg GAE g^-1 d.w. polyphenols and 2.0-5.3 mg g^-1 d.w. proline. Overall, according to the elemental analysis of lichen from Baskunchak Nature Reserve compared to the Southern Crimean seashore, the vicinity of Baskunchak Salty Lake elicited increased environmental levels of Cr, Si, Li, Fe, Co, Ni and Ca.

Specialization patterns in symbiotic associations: A community perspective over spatial scales

Specialization, contextualized in a resource axis of an organism niche, is a core concept in ecology. In biotic interactions, specialization can be determined by the range of interacting partners. Evolutionary and ecological factors, in combination with the surveyed scale (spatial, temporal, biological, and/or taxonomic), influence the conception of specialization. This study aimed to assess the specialization patterns and drivers in the lichen symbiosis, considering the interaction between the principal fungus (mycobiont) and the associated Nostoc (cyanobiont), from a community perspective considering different spatial scales. Thus, we determined Nostoc phylogroup richness and composition of lichen communities in 11 Nothofagus pumilio forests across a wide latitudinal gradient in Chile. To measure specialization, cyanobiont richness, Simpson's and d' indices were estimated for 37 mycobiont species in these communities. Potential drivers that might shape Nostoc composition and specialization measures along the environmental gradient were analysed. Limitations in lichen distributional ranges due to the availability of their cyanobionts were studied. Turnover patterns of cyanobionts were identified at multiple spatial scales. The results showed that environmental factors shaped the Nostoc composition of these communities, thus limiting cyanobiont availability to establish the symbiotic association. Besides, specialization changed with the spatial scale and with the metric considered. Cyanolichens were more specialized than cephalolichens when considering partner richness and Simpson's index, whereas the d' index was mostly explained by mycobiont identity. Little evidence of lichen distributional ranges due to the distribution of their cyanobionts was found. Thus, lichens with broad distributional ranges either associated with several cyanobionts or with widely distributed cyanobionts. Comparisons between local and regional scales showed a decreasing degree of specialization at larger scales due to an increase in cyanobiont richness. The results support the context dependency of specialization and how its consideration changes with the metric and the spatial scale considered. Subsequently, we suggest considering the entire community and widening the spatial scale studied as it is crucial to understand factors determining specialization.

Ocean crossers: a tale of disjunctions and speciation in the dwarf-fruticose Lichina (lichenized Ascomycota)

Lichens thrive in rocky coastal areas in temperate and cold regions of both hemispheres. Species of the genus Lichina, which form characteristic black fruiting thalli associated with cyanobacteria, often create distinguishable bands in the intertidal and supralittoral zones. The present study uses a comprehensive specimen dataset and four gene loci to (1) delineate and discuss species boundaries in this genus, (2) assess evolutionary relationships among species, and (3) infer the most likely causes of their current geographic distribution in the Northern and Southern hemispheres. A dated phylogeny describes the time frame in which extant disjunctions of species and populations were established. The results showed that the genus is integrated by four species, with Lichina pygmaea, L. confinis and the newly described L. canariensis from rocky seashores in the Canary Islands, occurring in the Northern Hemisphere, whereas L. intermedia is restricted to the Southern Hemisphere. Lichina intermedia hosted a much higher intraspecific genetic diversity than the other species, with subclades interpreted as species-level lineages by the different species delimitation approaches. However, a conservative taxonomic approach was adopted. This species showed a striking disjunct distribution between Australasia and southern South America. The timing for the observed interspecific and intraspecific divergences and population disjunctions postdated continental plate movements, suggesting that long-distance dispersal across body waters in the two hemispheres played a major role in shaping the current species distributions. Such ocean crossings were, as in L. canariensis, followed by speciation. New substitution rates for the nrITS of the genus Lichina were inferred using a tree spanning the major Ascomycota lineages calibrated using fossils. In conclusion, this work lays the foundation for a better understanding of the evolution through time and space of maritime lichens.

Biosynthetic Potential of Hypogymnia Holobionts: Insights into Secondary Metabolite Pathways

Lichens are symbiotic associations consisting of a photobiont (algae or cyanobacteria) and a mycobiont (fungus). They are known to produce a variety of unique secondary metabolites. To access this biosynthetic potential for biotechnological applications, deeper insights into the biosynthetic pathways and corresponding gene clusters are necessary. Here we provide a comprehensive view of the biosynthetic gene clusters of all organisms comprising a lichen thallus: fungi, green algae, and bacteria. We present two high-quality PacBio metagenomes, in which we identified a total of 460 biosynthetic gene clusters. Lichen mycobionts yielded 73-114 clusters, other lichen associated ascomycetes 8-40, green algae of the genus Trebouxia 14-19, and lichen-associated bacteria 101-105 clusters. The mycobionts contained mainly T1PKSs, followed by NRPSs, and terpenes; Trebouxia reads harbored mainly clusters linked to terpenes, followed by NRPSs and T3PKSs. Other lichen-associated ascomycetes and bacteria contained a mix of diverse biosynthetic gene clusters. In this study, we identified for the first time the biosynthetic gene clusters of entire lichen holobionts. The yet untapped biosynthetic potential of two species of the genus Hypogymnia is made accessible for further research.

First Whole Genome Sequence and Flow Cytometry Genome Size Data for the Lichen-Forming Fungus Ramalina farinacea (Ascomycota)

Lichen-forming fungi are a diverse and ecologically important group of obligate mutualistic symbionts. Due to difficulties with maintaining them in culture and their extremely slow growth, lichenologists are increasingly opting for metagenomic sequencing followed by symbiont genome separation using bioinformatic pipelines. However, without knowing the true genome size of the lichen-forming fungus, we cannot quantify the completeness of the genome assembly and the efficacy of the bioinformatic filtering. To address this issue, we report here the first whole-genome assembly for the lichen-forming fungus Ramalina farinacea (L.) Ach. sequenced with Oxford Nanopore long-read technology alongside direct measurements of its genome size using flow cytometry. The assembly showed high contiguity (N50 = 1.55 Mbp) and gene set completeness (BUSCO = 95.8%). The highly robust genome size obtained of 33.61 Mbp/1C (CV% = 2.98) showed our assembly covered 97% of the entire genome. Our results demonstrate that accurate genome size measurements can be obtained directly from lichen thalli and used to provide a benchmark for assessing true cytometric completeness of metagenome-derived assemblies.

Discovery and excavation of lichen bioactive natural products

Lichen natural products are a tremendous source of new bioactive chemical entities for drug discovery. The ability to survive in harsh conditions can be directly correlated with the production of some unique lichen metabolites. Despite the potential applications, these unique metabolites have been underutilized by pharmaceutical and agrochemical industries due to their slow growth, low biomass availability, and technical challenges involved in their artificial cultivation. At the same time, DNA sequence data have revealed that the number of encoded biosynthetic gene clusters in a lichen is much higher than in natural products, and the majority of them are silent or poorly expressed. To meet these challenges, the one strain many compounds (OSMAC) strategy, as a comprehensive and powerful tool, has been developed to stimulate the activation of silent or cryptic biosynthetic gene clusters and exploit interesting lichen compounds for industrial applications. Furthermore, the development of molecular network techniques, modern bioinformatics, and genetic tools is opening up a new opportunity for the mining, modification, and production of lichen metabolites, rather than merely using traditional separation and purification techniques to obtain small amounts of chemical compounds. Heterologous expressed lichen-derived biosynthetic gene clusters in a cultivatable host offer a promising means for a sustainable supply of specialized metabolites. In this review, we summarized the known lichen bioactive metabolites and highlighted the application of OSMAC, molecular network, and genome mining-based strategies in lichen-forming fungi for the discovery of new cryptic lichen compounds.

Lichen-Derived Actinomycetota: Novel Taxa and Bioactive Metabolites

Actinomycetes are essential sources of numerous bioactive secondary metabolites with diverse chemical and bioactive properties. Lichen ecosystems have piqued the interest of the research community due to their distinct characteristics. Lichen is a symbiont of fungi and algae or cyanobacteria. This review focuses on the novel taxa and diverse bioactive secondary metabolites identified between 1995 and 2022 from cultivable actinomycetota associated with lichens. A total of 25 novel actinomycetota species were reported following studies of lichens. The chemical structures and biological activities of 114 compounds derived from the lichen-associated actinomycetota are also summarized. These secondary metabolites were classified into aromatic amides and amines, diketopiperazines, furanones, indole, isoflavonoids, linear esters and macrolides, peptides, phenolic derivatives, pyridine derivatives, pyrrole derivatives, quinones, and sterols. Their biological activities included anti-inflammatory, antimicrobial, anticancer, cytotoxic, and enzyme-inhibitory actions. In addition, the biosynthetic pathways of several potent bioactive compounds are summarized. Thus, lichen actinomycetes demonstrate exceptional abilities in the discovery of new drug candidates.

Pediatric lichen planus: A single-center retrospective review of 26 patients with follow up

BACKGROUND/OBJECTIVES

Pediatric lichen planus (LP) is rare with variable prevalence and atypical presentations compared to adults. Data on LP are lacking for the pediatric population in the United States. We present demographics, presentations, and treatments for a pediatric LP cohort.

METHODS

We reviewed 26 patients diagnosed with LP at 20 years or younger. Treatment responses were defined as no response, partial response, and complete response.

RESULTS

Demographics included 54% females and median diagnosis age of 16 years (range 6-20). Most patients presented with cutaneous LP (65%), with fewer having associated oral (23%), nail (7.7%), or genital (3.8%) involvement. Some had cutaneous-only LP (38%) or strictly mucosal LP (oral-only 19% and genital-only 15%). LP lesions were pruritic (50%), painful (19%), and/or asymptomatic (35%). Complete/partial responses occurred with medium-potency topical corticosteroids in cutaneous (n = 7; 64%), oral (n = 3; 75%), and genital LP (n = 3; 100%), with high/ultra-high potency topical corticosteroids in oral LP (n = 6; 86%), and with topical calcineurin inhibitors in genital LP (n = 2; 100%). Side effects were clobetasol-related oral candidiasis and biopsy-related penile depressed scar. Most patients with available follow-up achieved remission (n = 17; 81%).

CONCLUSIONS

Pediatric LP usually presents in adolescence with cutaneous involvement and is symptomatic. However, patients frequently can have oral, genital, or nail lesions or may be asymptomatic, so they need thorough examinations and follow-up. Long-term remission is common due to treatment or natural disease course. Medium-potency corticosteroids are recommended for cutaneous, oral, and genital LP. Various other local and systemic therapies exist with successful treatment responses.

Synthesis and Antioxidant Evaluation of O-Methylated Emodacidamides: Starting from Parietin, a Secondary Metabolite of Lichen Xanthoria parietina

Polyhydroxy-anthraquinones bearing amino acids are found rather seldom in nature. Emodacidamides, isolated from a marine-derived fungus, Penicillium sp. SCSIO sof101 by Luo et al. (2017) are the first natural example of amino acid conjugated anthraquinone. In this study, O-methylated emodacidamides and emodinic acid-anilides were synthesized starting from parietin, extracted from the lichen Xanthoria parietina (L.) Th. Fr. The structural elucidations of prepared compounds were confirmed by 1D and 2D NMR analyses including HSQC and HMBC techniques. In addition, all newly synthesized compounds were evaluated for the antioxidant activities with free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging. The synthesized compounds showed low to moderate antioxidant and DPPH scavenging activities. The antioxidant activities were supported within quantum chemical calculations using the DFT-B3LYP/6-311++G(d,p) level of theory. It is observed that the antioxidant activity of emodacidamides mostly depends on the phenolic groups on anthraquinone ring. The phenolic groups on other substituents help to improve antioxidant activity and also the position of hydroxy group is a decisive factor for antioxidant ability.

Prototaxites reinterpreted as mega-rhizomorphs, facilitating nutrient transport in early terrestrial ecosystems

The enigmatic fossil Prototaxites found in successions ranging from the Middle Ordovician to the Upper Devonian was originally described as having conifer affinity. The current debate, however, suggests that they probably represent gigantic algal-fungal symbioses. Our re-investigation of permineralized Prototaxites specimens from two localities, the Heider quarry in Germany and the Bordeaux quarry in Canada, reveals striking anatomical similarities with modern fungal rhizomorphs Armillaria mellea. We analysed extant fungal rhizomorphs and fossil Prototaxites through light microscopy of their anatomy, Fourier transform infrared spectroscopy, X-ray microscopy, and Raman spectroscopy. Based on these comparisons, we interpret the Prototaxites as fungi. The detailed preservation of cell walls and possible organelles seen in transverse sections of Prototaxites reveal that fossilization initiated while the organism was alive, inhibiting the collapse of delicate cellular structures. Prototaxites has been interpreted to grow vertically by many previous workers. Here we propose an alternative view that Prototaxites represents a complex hyphal aggregation (rhizomorph) that may have grown horizontally similar to modern complex aggregated mycelial growth forms, such as cords and rhizomorphs. Their main function was possibly to redistribute water and nutrition from nutrient-rich to nutrient-poor areas facilitating the expansion for early land plant communities.

Successional Development of the Phototrophic Community in Biological Soil Crusts on Coastal and Inland Dunes

(1) Biological soil crusts (biocrusts) are microecosystems consisting of prokaryotic and eukaryotic microorganisms growing on the topsoil. This study aims to characterize changes in the community structure of biocrust phototrophic organisms along a dune chronosequence in the Baltic Sea compared to an inland dune in northern Germany. (2) A vegetation survey followed by species determination and sediment analyses were conducted. (3) The results highlight a varying phototrophic community composition within the biocrusts regarding the different successional stages of the dunes. At both study sites, a shift from algae-dominated to lichen- and moss-dominated biocrusts in later successional dune types was observed. The algae community of both study sites shared 50% of the identified species while the moss and lichen community shared less than 15%. This indicates a more generalized occurrence of the algal taxa along both chronosequences. The mosses and lichens showed a habitat-specific species community. Moreover, an increase in the organic matter and moisture content with advanced biocrust development was detected. The enrichment of carbon, nitrogen, and phosphorus in the different biocrust types showed a similar relationship. (4) This relation can be explained by biomass growth and potential nutrient mobilization by the microorganisms. Hence, the observed biocrust development potentially enhanced soil formation and contributed to nutrient accumulation.

Lichen Biomonitoring of Airborne Microplastics in Milan (N Italy)

This study investigated the deposition of airborne microplastics (MPs) in the urban area of Milan across 12 sites and at a background control site (northern Italy) using 3-month transplants of the fruticose lichen species Evernia prunastri (exposed in triplicate). The primary objective was to evaluate the use of lichen transplants for the assessment of MP deposition; as such, the study sites spanned a gradient in vehicular traffic and population density across four concentric land-use zones (i.e., urban parks, centre, semi-periphery, and periphery). A total of 149 MP particles were detected in the exposed lichen samples; 94.6% were classified as fibres and 5.4% as fragments. The control site and urban parks experienced a similar number of MPs per gram of dry lichen (20-26 MP/g), while a higher number of MPs were detected in central and peripheral areas (44-56 MP/g), with a clear increasing gradient from the city centre towards the periphery. We estimated the MP deposition in Milan to be in the range of 43-119 MPs m²/d, indicating that people living in Milan are exposed to airborne MPs, with potential health effects. This study suggests that lichens are suitable biomonitors of airborne MPs under a relatively short exposure of three months in urban environments.

Advances in Research on Bioactivity, Toxicity, Metabolism, and Pharmacokinetics of Usnic Acid In Vitro and In Vivo

Lichens are among the most widely distributed plants on earth and have the longest growth cycle. Usnic acid is an abundant characteristic secondary metabolite of lichens and the earliest lichen compound used commercially. It has diverse pharmacological activities, such as anti-inflammatory, antibacterial, antiviral, anticancer, antioxidant, and photoprotective effects, and promotes wound healing. It is widely used in dietary supplements, daily chemical products (fodder, dyes, food, perfumery, and cosmetics), and medicine. However, some studies have found that usnic acid can cause allergic dermatitis and drug-induced liver injury. In this paper, the bioactivity, toxicity, in vivo and in vitro metabolism, and pharmacokinetics of usnic acid were summarized. The aims were to develop and utilize usnic acid and provide reference for its future research.

A new species and four new records of Bacidia (Lecanorales, Ramalinaceae) from South Korea, with a key to Korean species

A new species, Bacidiafuscopallida Lee & Heo and four new records, B.ekmaniana R. C. Harris, Ladd & Lendemer, B.friesiana (Hepp) Körb., B.heterochroa (Müll. Arg.) Zahlbr. and B.suffusa (Fr.) A. Schneid., are described from South Korea. Bacidiafuscopallida differs from B.diffracta S. Ekman, the most similar species, by warted but non-granular thallus, paler and smaller apothecia without pruina, proper exciple without crystals, over 11-septate ascospores and smaller pycnidia and pycnoconidia. Bacidiaekmaniana is recorded new to Asia, B.heterochroa is reported new to northeastern Asia and B.friesiana and B.suffusa are new to Korea. Molecular analyses employing internal transcribed spacer (ITS) sequences strongly support the classification of the five species of Bacidia. A surrogate key is provided to assist in the identification of all 19 taxa in Bacidia of Korea.

Comprehensive Lichenometabolomic Exploration of Ramalina conduplicans Vain Using UPLC-Q-ToF-MS/MS: An Identification of Free Radical Scavenging and Anti-Hyperglycemic Constituents

In this study, we propose ultra-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UPLC-QToF-MS/MS)-guided metabolite isolation as a choice analytical approach to the ongoing structure−activity investigations of chemical isolates from the edible lichen, Ramalina conduplicans Vain. This strategy led to the isolation and identification of a new depside (5) along with 13 known compounds (1−4, 6−14), most of which being newly described in this lichen species. The structures of the isolates were established by detailed analysis of their spectral data (IR, NMR, and Mass). The acetone extract was further analyzed by UPLC-Q-ToF-MS/MS in a negative ionization mode, which facilitated the identification and confirmation of 18 compounds based on their fragmentation patterns. The antioxidant capacities of the lichen acetone extract (AE) and isolates were measured by tracking DPPH and ABTS free radical scavenging activities. Most isolates displayed marked radical scavenging activities against ABTS while moderate activities were observed against DPPH radical scavenging. Except for atranol (14), oxidative DNA damage was limited by all the tested compounds, with a marked protection for the novel isolated compound (5), as previously noted for the acetone extract (p < 0.001). Furthermore, compound (4) and acetone extract (AE) have inhibited intestinal α-glucosidase enzyme significantly (p < 0.01). Although some phytochemical studies were already performed on this lichen, this study provided new insights into the isolation and identification of bioactive compounds, illustrating interest in future novel analytical techniques.

Potential human health risks of toxic/harmful elements by consumption of Pseudevernia furfuracea

The potential human health risks of some toxic/harmful elements related to the consumption of Pseudevernia furfuracea (L.) Zopf. were investigated. The toxic/harmful elements (cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), and zinc (Zn)) were determined in P. furfuracea. According to the analysis result, the maximum (max.) toxic/harmful element value was 62 ± 3.1 mg/kg for Mn and minimum (min.) value was 0.19 ± 0.01 mg/kg for Cd. The estimated daily exposure doses (EDEXDs) for men, women and children were dietary (bread) > dietary (tea) > dermal. For dietary (bread) and dietary (tea) non-carcinogenic (HQ) risk was children > women > men. For dermal, HQ risk was women > children > men. Hazard index (HI) value for men was >1 for Cr. HI value for men was 1.36 for Cr. HI value for women was >1 for Cr and Mn. HI values for women were 1.54 for Cr and 1.01 for Mn. Also, the HI value for children was >1 for Cr, Mn, and Pb. HI values for children were 3.44 for Cr, 2.24 for Mn, and 1.66 for Pb. This situation showed that there was a non-carcinogenic risk. Carcinogenic risk values were dietary (bread) > dietary (tea) > dermal. The total max. carcinogenic value was 1.97E-03 for Cr while the total min. carcinogenic value was 1.31E-05 for Pb. As a result, it has been determined that there may be a risk of cancer due to the consumption of lichen as bread and this situation may adversely affect human health.

Evolution-Informed Discovery of the Naphthalenone Biosynthetic Pathway in Fungi

Fungi produce a wide diversity of secondary metabolites with interesting biological activities for the health, industrial, and agricultural sectors. While fungal genomes have revealed an unexpectedly high number of biosynthetic pathways that far exceeds the number of known molecules, accessing and characterizing this hidden diversity remain highly challenging. Here, we applied a combined phylogenetic dereplication and comparative genomics strategy to explore eight lichenizing fungi. The determination of the evolutionary relationships of aromatic polyketide pathways resulted in the identification of an uncharacterized biosynthetic pathway that is conserved in distant fungal lineages. The heterologous expression of the homologue from Aspergillus parvulus linked this pathway to naphthalenone compounds, which were detected in cultures when the pathway was expressed. Our unbiased and rational strategy generated evolutionary knowledge that ultimately linked biosynthetic genes to naphthalenone polyketides. Applied to many more genomes, this approach can unlock the full exploitation of the fungal kingdom for molecule discovery.

Arthropods and other biota associated with the Azorean trees and shrubs: Laurusazorica (Seub) Franco (Magnoliophyta, Magnoliopsida, Laurales, Lauraceae)

This study explores the composition and structure of species communities associated with the native Azorean tree species Laurusazorica (Seub) Franco (Magnoliophyta, Magnoliopsida, Laurales, Lauraceae). Communities were sampled in six Islands covering the occidental (Flores), central (Faial, Pico, Terceira) and eastern (São Miguel, Santa Maria) groups of Azores Archipelago during the BALA project, using standardised sampling protocols for surveying canopy arthropod fauna. In addition, the study characterises the distribution of species regarding their colonisation status and feeding modes and, finally, compares communities of different Islands. Ninety-four arthropod species totalling 10,313 specimens were collected on L.azorica. The Arthropod community was dominated by Hemiptera species, most of them being herbivores. Endemic and native species showed a very high abundance representing about 94% of the total species abundance. However, despite introduced species being represented by few individuals (6% of the total abundance), their diversity was remarkable (28 species and no significant difference with diversity found in endemic and native species communities). Analysis of rarity patterns revealed a stable community of endemic species (alpha gambin SAD model approaching a log-normal shape), intermediate stable community of native species (alpha SAD gambin model approaching a poisson log-normal) and a less stable community of introduced species (alpha SAD gambin model approaching a log-series shape). A dissimilarity analysis revealed high similarity between communities of Terceira and Pico and high dissimilarity between Flores and Faial communities. We observed a clear individualisation of the different islands when considering endemic species, whereas we observed high overlap when considering native and introduced species groups. Canopy community distribution confirms the results obtained in a previous study which suggest the stability of native and endemic arthropods species communities over introduced species community in native forests fragments. Arthropod species were richer than bryophytes, lichens and vascular plants species. We found that L.azorica serve as the substrate for very few vascular plants species (four epiphytes species), which were present in all Islands, except Elaphoglossumsemicylindricum, which does not occur in Santa Maria. L.azorica shelters a significant number of bryophytes and lichens species. Thirty-two lichens and 92 bryophyte species, including 57 liverworts and 35 mosses, are referred to this phorophyte. Five bryophyte species, all Azorean endemics, are considered Endangered by IUCN Criteria. L.azorica harbours a poor community of epiphyte vascular plant species and all of them were ferns, but the community of bryophytes and lichens are not negligible although very low compared to the community found on other previously studied Azorean trees, the Azorean cedar Juniperusbrevifolia. The present study shows that most islands present particular species distribution patterns without geographical correlation and that conservation programmes should be adapted to each Island. The study, therefore, calls for a specialisation of conservation programmes for each of the Islands.

Contrasting Patterns of Climatic Niche Divergence in Trebouxia-A Clade of Lichen-Forming Algae

Lichen associations are overwhelmingly supported by carbon produced by photosynthetic algal symbionts. These algae have diversified to occupy nearly all climates and continents; however, we have a limited understanding of how their climatic niches have evolved through time. Here we extend previous work and ask whether phylogenetic signal in, and the evolution of, climatic niche, varies across climatic variables, phylogenetic scales, and among algal lineages in Trebouxia—the most common genus of lichen-forming algae. Our analyses reveal heterogeneous levels of phylogenetic signal across variables, and that contrasting models of evolution underlie the evolution of climatic niche divergence. Together these analyses demonstrate the variable processes responsible for shaping climatic tolerance in Trebouxia, and provide a framework within which to better understand potential responses to climate change-associated perturbations. Such predictions reveal a disturbing trend in which the pace at which modern climate change is proceeding will vastly exceed the rate at which Trebouxia climatic niches have previously evolved.

Understanding the Biosynthesis of Paxisterol in Lichen-Derived Penicillium aurantiacobrunneum for Production of Fluorinated Derivatives

The U.S. endemic lichen (Niebla homalea)-derived Penicillium aurantiacobrunneum produced a cytotoxic paxisterol derivative named auransterol (2) and epi-citreoviridin (6). Feeding assay using ¹³C₁-labelled sodium acetate not only produced C-13-labelled paxisterol but also confirmed the biosynthetic origin of the compound. The fluorination of bioactive compounds is known to improve pharmacological and pharmacokinetic effects. Our attempt to incorporate the fluorine atom in paxisterol and its derivatives using the fluorinated precursor sodium monofluoroacetate resulted in the isolation of 7-monofluoroacetyl paxisterol (7). The performed culture experiment, as well as the isolation and structure elucidation of the new fluorinated paxisterol, is discussed herein.

Platismatia glauca-Lichen species with suppressive properties on migration and invasiveness of two different colorectal carcinoma cell lines

Platismatia glauca is a popular lichen traditionally used as a spice and possesses significant anti-cancer potential, whose anti-migratory/anti-invasive properties were mostly disregarded. Migration/invasion of cancer cells is processed in cancer metastasis and targeting their markers is an important strategy in anti-cancer treatment. We examined the anti-migratory/anti-invasive properties of P. glauca extract on two colorectal carcinoma cell lines (HCT-116 and SW-480) and elucidated possible mechanisms underlying these properties. Cell migration was evaluated by wound healing and RTCA methods. Immunofluorescent assay was used for the analysis of protein, while qRT-PCR for gene expression of migratory/invasive markers. ELISA assay was applied for the determination of MMP-9 concentration. P. glauca extract inhibited the motility of tested cells, by reducing pro-migratory/pro-invasive markers and potentially retaining intercellular connections. Treatment showed cell-selective effects, and HCT-116 cells were more responsive. Our study presents important scientific novelty, thus these lichen properties should be furtherly examined regarding the amelioration of anti-cancer treatment. PRACTICAL APPLICATIONS: Based on the evidence we provided in the present study, we have demonstrated that lichen species Platismatia glauca possess important biological activity, which has not been sufficiently investigated so far. It is of great importance to explore its anti-cancer potential, not only from a cytotoxic point of view but especially anti-migratory and anti-invasive. Herein, we showed that this species expresses significant suppressive effects on migration and invasiveness of colorectal carcinoma cells. This tested lichen has the potential to be used as a natural complementary anti-cancer treatment, with special reference on the dose applied and type of carcinoma. Our study represents a significant novelty in the field of scientific investigation of lichens and natural products, and further detailed studies are needed on in vitro and in vivo model systems.

as Antidiabetic Agents

Lichen Usnea sp. is potential as a new natural medicine. This study report isolation of secondary metabolites from lichen Usnea sp. and α-glucosidase inhibitory, which is potential as an antidiabetic agent. Lichen powder was macerated using methanol, separated using column chromatography gravity and thin-layer chromatography. The crystalline was isolated and purified by the recrystallization process for obtaining pure compound. The isolated compound was determined using FTIR and NMR spectroscopy (¹H and ¹³C). The results showed that the isolated compound was yellow needle crystals. Based on the spectra data interpretation, it was obtained usnic acid compound with the molecular formula of C₁₈H₁₆O₇. The α-glucosidase inhibitory activity test showed that the usnic acid had activity in inhibiting the α-glucosidase enzyme with an IC₅₀ value of 106.78 µg/mL. The usnic acid from Usnea sp. has a very good impact on the source of natural compounds as an antidiabetic drug in the future.

Choosing the Right Life Partner: Ecological Drivers of Lichen Symbiosis

Lichens are an iconic example of symbiotic systems whose ecology is shaped by the requirements of the symbionts. Previous studies suggest that fungal (mycobionts) as well as photosynthesizing (phycobionts or cyanobionts) partners have a specific range of acceptable symbionts that can be chosen according to specific environmental conditions. This study aimed to investigate the effects of climatic conditions and mycobiont identity on phycobiont distribution within the lichen genera Stereocaulon, Cladonia, and Lepraria. The study area comprised the Canary Islands, Madeira, Sicily, and the Aeolian Islands, spanning a wide range of climatic conditions. These islands are known for their unique and diverse fauna and flora; however, lichen phycobionts have remained unstudied in most of these areas. In total, we genetically analyzed 339 lichen samples. The phycobiont pool differed significantly from that outside the studied area. Asterochloris mediterranea was identified as the most abundant phycobiont. However, its distribution was limited by climatic constraints. Other species of Asterochloris and representatives of the genera Chloroidium, Vulcanochloris, and Myrmecia were also recovered as phycobionts. The selection of symbiotic partners from the local phycobiont pool was driven by mycobiont specificity (i.e., the taxonomic range of acceptable partners) and the environmental conditions, mainly temperature. Interestingly, the dominant fungal species responded differently in their selection of algal symbionts along the environmental gradients. Cladonia rangiformis associated with its phycobiont A. mediterranea in a broader range of temperatures than Stereocaulon azoreum, which favors other Asterochloris species along most of the temperature gradient. Stereocaulon vesuvianum associated with Chloroidium spp., which also differed in their temperature optima. Finally, we described Stereocaulon canariense as a new endemic species ecologically distinct from the other Stereocaulon species on the Canary Islands.

nov., a madurastatin A1-producing strain isolated from lichen in Thailand

An actinomycete strain, LCR2-06^T, isolated from a lichen sample on rock collected from Chiang Rai Province (Pong Phra Bat Waterfall), Thailand, was characterized using a polyphasic approach. The strain grew at 25-45 °C, pH 6-11 and on International Streptomyces Project 2 agar plate with 5 % (w/v) NaCl. It contained meso-diaminopimelic acid as the diamino acid in whole-cell hydrolysates. Rhamnose, ribose, xylose, madurose, glucose and galactose were detected as whole-cell sugar hydrolysates. Mycolic acids were absent. The N-acyl type of muramic acid was acetyl. The strain contained C_16 : 0, TBSA 10-methyl C_18 : 0 and 2-hydroxy C_16 : 0 as the predominant fatty acids and MK-9(H₆), MK-9(H₄) and MK-9(H₈) as the major menaquinones. The major polar lipids were diphosphatidylglycerol, phosphatidylinositol and unidentified phospholipid. The draft genome of strain LCR2-06^T was closely related to Actinomadura barringtoniae TBRC 7225^T (99.2 %), Actinomadura nitritigenes NBRC 15918^T (98.8 %), Actinomadura montaniterrae TISTR 2400^T (98.5 %) and Actinomadura physcomitrii JCM 33455^T (97.9 %). The draft genome of LCR2-06^T was 11.1 Mb with 10 588 coding sequences with an average G+C content of 72.7 mol%. Results of genomic analysis revealed that the ANIb and ANIm values between strain LCR2-06^T and A. montaniterrae TISTR 2400^T were 90.0 and 92.0 %, respectively. The digital DNA-DNA hybridization value was 43.9 % in comparison with the draft genome of A. montaniterrae TISTR 2400^T. The strain produced an antibacterial compound active against Bacillus subtilis ATCC 6633 and Kocuria rhizophila ATCC 9341. The results of taxonomic analysis suggested that strain LCR2-06^T represented a novel species of the genus Actinomadura for which the name Actinomadura violacea sp. nov. is proposed. The type strain is LCR2-06^T (=JCM 33065^T=KCTC 49547^T=NBRC 114810^T=LMG 32136^T=TISTR 2935^T).

Transfer of Natural Radionuclides in Terrestrial Food Chains-A Review of Investigations in Finland

Transfer of natural radionuclides ²¹⁰Pb, ²¹⁰Po, ²³⁸U, and ^228,230,232Th in subarctic food chains has been studied in Finland since the 1960s. The unique food chain lichen-reindeer-man related to Sami people in Finnish Lapland and other food chain options, from berries or mushrooms to man, have been explored and the activity concentrations of natural radionuclides in biological samples determined. The results from Finnish radioecological studies are summarized and differences in bioaccumulation between different radionuclides are discussed. It was found out that, although a substantial amount of activity concentration data exist from the research projects executed in Finland during the last 6 decades, more data, especially from U and Th, in biological environment and humans would be useful, e.g., for modeling purposes and for improved assessment of bioaccumulation and adverse effects (both radiological and chemical) of radionuclides.

The Natural Compound Hydrophobic Usnic Acid and Hydrophilic Potassium Usnate Derivative: Applications and Comparisons

Usnic acid is the best-studied lichen metabolite, presenting several biological activities, such as antibacterial, immunostimulating, antiviral, antifungal, anti-inflammatory, and antiparasitic agents; despite these relevant properties, it is a hydrophobic and toxic molecule. In this context, scientific research has driven the development of innovative alternatives, considering usnic acid as a source of raw material in obtaining new molecules, allowing structural modifications (syntheses) from it. The purpose is to optimize biological activities and toxicity, with less concentration and/or response time. This work presents a literature review with an analogy of the hydrophobic molecule of usnic acid with its hydrophilic derivative of potassium usnate, emphasizing the elucidation and structural characteristics, biological activities, and toxicological aspects of both molecules, and the advantages of using the promising derivative hydrophilic in different in vitro and in vivo assays when compared to usnic acid.

UAV RGB, thermal infrared and multispectral imagery used to investigate the control of terrain on the spatial distribution of dryland biocrust

Biocrusts (topsoil communities formed by mosses, lichens, bacteria, fungi, algae, and cyanobacteria) are a key biotic component of dryland ecosystems. Whilst climate patterns control the distribution of biocrusts in drylands worldwide, terrain and soil attributes can influence biocrust distribution at landscape scale. Multi-source unmanned aerial vehicle (UAV) imagery was used to map and study biocrust ecology in a typical dryland ecosystem in central Spain. Red, green and blue (RGB) imagery was processed using structure-from-motion techniques to map terrain attributes related to microclimate and terrain stability. Multispectral imagery was used to produce accurate maps (accuracy > 80%) of dryland ecosystem components (vegetation, bare soil and biocrust composition). Finally, thermal infrared (TIR) and multispectral imagery was used to calculate the apparent thermal inertia (ATI) of soil and to evaluate how ATI was related to soil moisture (r 2 = 0.83). The relationship between soil properties and UAV-derived variables was first evaluated at the field plot level. Then, the maps obtained were used to explore the relationship between biocrusts and terrain attributes at ecosystem level through a redundancy analysis. The most significant variables that explain biocrust distribution are: ATI (34.4% of variance, F = 130.75; p < 0.001), Elevation (25.8%, F = 97.6; p < 0.001), and potential solar incoming radiation (PSIR) (52.9%, F = 200.1; p < 0.001). Differences were found between areas dominated by lichens and mosses. Lichen-dominated biocrusts were associated with areas with high slopes and low values of ATI, with soil characterized by a higher amount of soluble salts, and lower amount of organic carbon, total phosphorus (Ptot) and total nitrogen (Ntot). Biocrust-forming mosses dominated lower and moister areas, characterized by gentler slopes and higher values of ATI with soils with higher contents of organic carbon, Ptot and Ntot. This study shows the potential to use UAVs to improve our understanding of drylands and to evaluate the control that the terrain has on biocrust distribution.

Lichens buffer tundra microclimate more than the expanding shrub Betula nana

BACKGROUND AND AIMS

In tundra systems, soil-borne lichens are often the dominant groundcover organisms, and act to buffer microclimate extremes within or at the surface of the soil. However, shrubs are currently expanding across tundra systems, potentially causing major shifts in the microclimate landscape.

METHODS

Here, we compared soil temperature and moisture underneath the dwarf birch Betula nana and seven abundant lichen species in sub-alpine Norway. We also examined mixtures of lichens and dwarf birch - an intermediate phase of shrubification - and measured several functional traits relating to microclimate.

KEY RESULTS

We found that all lichen species strongly buffered the daily temperature range, on average reducing maximum temperatures by 6.9 °C (± 0.7 s.d.) and increasing minimum temperatures by 1.0 °C (± 0.2 s.d.) during summer. The dwarf birch had a much weaker effect (maximum reduced by 2.4 ± 5.0 °C and minimum raised by 0.2 ± 0.9 °C). In species mixtures, the lichen effect predominated, affecting temperature extremes by more than would be expected from their abundance. Lichens also tended to reduce soil moisture, which could be explained by their ability to intercept rainfall. Our trait measurements under laboratory conditions suggest that, on average, lichens can completely absorb a 4.09 mm (± 1.81 s.d.) rainfall event, which might be an underappreciated part of lichen-vascular plant competition in areas where summer rainfall events are small.

CONCLUSIONS

In the context of shrubification across tundra systems, our findings suggest that lichens will continue to have a large effect on microclimate until they are fully excluded, at which point microclimate extremes will increase greatly.

Global diversity and ecological drivers of lichenised soil fungi

Lichens play crucial roles in sustaining the functioning of terrestrial ecosystems; however, the diversity and ecological factors associated with lichenised soil fungi remain poorly understood. To address this knowledge gap, we used a global field survey including information on fungal sequences of topsoils from 235 terrestrial ecosystems. We identified 880 lichenised fungal phylotypes across nine biomes ranging from deserts to tropical forests. The diversity and proportion of lichenised soil fungi peaked in shrublands and dry grasslands. Aridity index, plant cover and soil pH were the most important factors associated with the distribution of lichenised soil fungi. Furthermore, we identified Endocarpon, Verrucaria and Rinodina as some of the most dominant lichenised genera across the globe, and they had similar environmental preferences to the lichenised fungal community. In addition, precipitation seasonality and mean diurnal temperature range were also important in predicting the proportion of these dominant genera. Using this information, we were able to create the first global maps of the richness and the proportion of dominant genera of lichenised fungi. This work provides new insight into the global distribution and ecological preferences of lichenised soil fungi, and supports their dominance in drylands across the globe.

nov., isolated from lichen in Thailand

Two actinobacteria, designated as strain LDG1-01^T and LDG1-06^T, were isolated from lichen samples collected in Thailand. Results of morphological characterization, chemotaxonomic studies and 16S rRNA gene analysis indicated that both strains were members of the genus Actinoplanes. MK-9(H₄) was found as the major menaquinone. The major fatty acids were anteiso-C_15 : 0, iso-C_15 : 0, iso-C_16 : 0 and anteiso-C_17 : 0. Phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol were observed as the polar lipids, but differences in minor unidentified polar lipids were found between the strains. Results of comparative genome analysis based on average nucleotide identity and digital DNA-DNA hybridization calculations revealed that both strains showed values below 95 and 70 %, respectively, from each other and closely related Actinoplanes type strains. Based on data from this polyphasic study, strains LDG1-01^T and LDG1-06^T represent novel species of the genus Actinoplanes. The names proposed are Actinoplanes lichenicola sp. nov. (type strain, LDG1-01^T (=JCM 33066^T=TISTR 2982^T) and Actinoplanes ovalisporus sp. nov. (type strain, LDG1-06^T=JCM 33067^T=TISTR 2983^T).

Beneficial Effects of Liposomal Formulations of Lichen Substances: A Review

Lichens are commonly used as essential traditional medicines to treat various conditions, including skin disorders, wounds, digestive, respiratory, obstetric, and gynecological problems in many cultures in Africa, Asia, Europe, Haitian, Oceania, and North and South America. Lichens have been deeply investigated for their phytochemical properties, and to date, numerous compounds (also known as substances) have been successfully isolated from the extracts. However, the low solubility and bioavailability of pure lichen substances have been widely recognized as the significant issues hindering their biological applications. Recently, several groups have investigated the properties and the potential applications of lichen metabolites-based liposomal formulations and revealed a substantial improvement in their solubility, bioactivity, and toxicity in the animal. Thus, in this topical review, we aimed to provide an overview of liposomal structures, the efficacy of liposomal formulations, as well as their beneficial effects as compared to the free compounds themselves.

Macroecological diversification and convergence in a clade of keystone symbionts

Lichens are classic models of symbiosis, and one of the most frequent nutritional modes among fungi. The ecologically and geographically widespread lichen-forming algal (LFA) genus Trebouxia is one of the best-studied groups of LFA and associates with over 7000 fungal species. Despite its importance, little is known about its diversification. We synthesized twenty years of publicly available data by characterizing the ecological preferences of this group and testing for time-variant shifts in climatic regimes over a distribution of trees. We found evidence for limited shifts among regimes, but that disparate lineages convergently evolved similar ecological tolerances. Early Trebouxia lineages were largely forest specialists or habitat generalists that occupied a regime whose extant members occur in moderate climates. Trebouxia then convergently diversified in non-forested habitats and expanded into regimes whose modern representatives occupy wet-warm and cool-dry climates. We rejected models in which climatic diversification slowed through time, suggesting climatic diversification is inconsistent with that expected under an adaptive radiation. In addition, we found that climatic and vegetative regime shifts broadly coincided with the evolution of biomes and associated or similar taxa. Together, our work illustrates how this keystone symbiont from an iconic symbiosis evolved to occupy diverse habitats across the globe.