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1.
BMC Microbiol ; 24(1): 243, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965478

RESUMO

BACKGROUND: Lichens, traditionally considered as a simple partnership primarily between mycobiont and photobiont, are, in reality, complex holobionts comprised of a multitude of microorganisms. Lichen mycobiome represents fungal community residing within lichen thalli. While it is acknowledged that factors like the host lichen species and environmental conditions influence the structure of the lichen mycobiome, the existing research remains insufficient. To investigate which factor, host genus or location, has a greater impact on the lichen mycobiome, we conducted a comparative analysis of mycobiomes within Parmelia and Peltigera collected from both Turkey and South Korea, using high-throughput sequencing based on internal transcribed spacer region amplification. RESULTS: Overall, the lichen mycobiome was dominated by Capnodiales (Dothideomycetes), regardless of host or location. At the order level, the taxonomic composition was not significantly different according to lichen genus host or geographical distance. Hierarchical clustering of the top 100 abundant ASVs did not clearly indicate whether the lichen mycobiome was more influenced by host genus or location. Analyses of community similarity and partitioning variables revealed that the structure of the lichen mycobiome is more significantly influenced by location than by host genus. When analyzing the core mycobiome by host genus, the Peltigera mycobiome contained more ASV members than the Parmelia mycobiome. These two core mycobiomes also share common fungal strains, including basidiomycete yeast. Additionally, we used chi-squared tests to identify host genus-specialists and location-specialists. CONCLUSIONS: By comparing lichen mycobiomes of the same genera across different countries, our study advances our comprehension of these microbial communities. Our study elucidates that, although host species play a contributory role, geographic distance exerts a more pronounced impact on the structure of lichen mycobiome. We have made foundational contributions to understanding the lichen mycobiome occupying ecologically crucial niches. We anticipate that broader global-scale investigations into the fungal community structures will provide more detailed insights into fungal residents within lichens.


Assuntos
DNA Fúngico , Líquens , Micobioma , República da Coreia , Turquia , Líquens/microbiologia , Líquens/classificação , DNA Fúngico/genética , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Ascomicetos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Fungos/classificação , Fungos/isolamento & purificação , Fungos/genética , Parmeliaceae/genética
2.
Planta ; 260(2): 40, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954049

RESUMO

MAIN CONCLUSION: Rainwater most probably constitutes a relatively effective solvent for lichen substances in nature which have the potential to provide for human and environmental needs in the future. The aims were (i) to test the hypothesis on the potential solubility of lichen phenolic compounds using rainwater under conditions that partly reflect the natural environment and (ii) to propose new and effective methods for the water extraction of lichen substances. The results of spectrophotometric analyses of total phenolic metabolites in rainwater-based extracts from epigeic and epiphytic lichens, employing the Folin-Ciocalteu (F.-C.) method, are presented. The water solvent was tested at three pH levels: natural, 3, and 9. Extraction methods were undertaken from two perspectives: the partial imitation of natural environmental conditions and the potential use of extraction for economic purposes. From an ecological perspective, room-temperature water extraction ('cold' method) was used for 10-, 60-, and 120-min extraction periods. A variant of water extraction at analogous time intervals was an 'insolation' with a 100W light bulb to simulate the heat energy of the sun. For economic purposes, the water extraction method used the Soxhlet apparatus and its modified version, the 'tea-extraction' method ('hot' ones). The results showed that those extractions without an external heat source were almost ineffective, but insolation over 60- and 120-min periods proved to be more effective. Both tested 'hot' methods also proved to be effective, especially the 'tea-extraction' one. Generally, an increase in the concentration of phenolic compounds in water extracts resulted from an increasing solvent pH. The results show the probable involvement of lichen substances in biogeochemical processes in nature and their promising use for a variety of human necessities.


Assuntos
Líquens , Fenóis , Solubilidade , Espectrofotometria , Água , Líquens/química , Líquens/metabolismo , Fenóis/metabolismo , Fenóis/análise , Água/química , Solventes/química , Concentração de Íons de Hidrogênio , Chuva/química
3.
Int J Mol Sci ; 25(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39000176

RESUMO

Lichens are symbiotic organisms that effectively survive in harsh environments, including arid regions. Maintaining viability with an almost complete loss of water and the rapid restoration of metabolism during rehydration distinguishes lichens from most eukaryotic organisms. The lichen Xanthoria parietina is known to have high stress tolerance, possessing diverse defense mechanisms, including the presence of the bright-orange pigment parietin. While several studies have demonstrated the photoprotective and antioxidant properties of this anthraquinone, the role of parietin in the tolerance of lichens to desiccation is not clear yet. Thalli, which are exposed to solar radiation and become bright orange, may require enhanced desiccation tolerance. Here, we showed differences in the anatomy of naturally pale and bright-orange thalli of X. parietina and visualized parietin crystals on the surface of the upper cortex. Parietin was extracted from bright-orange thalli by acetone rinsing and quantified using HPLC. Although acetone rinsing did not affect PSII activity, thalli without parietin had higher levels of lipid peroxidation and a lower membrane stability index in response to desiccation. Furthermore, highly pigmented thalli possess thicker cell walls and, according to thermogravimetric analysis, higher water-holding capacities than pale thalli. Thus, parietin may play a role in desiccation tolerance by stabilizing mycobiont membranes, providing an antioxidative defense, and changing the morphology of the upper cortex of X. parietina.


Assuntos
Dessecação , Líquens , Líquens/metabolismo , Emodina/análogos & derivados , Emodina/metabolismo , Antraquinonas/metabolismo , Antraquinonas/química
4.
Microb Ecol ; 87(1): 87, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940862

RESUMO

The primary purpose of the study, as part of the planned conservation work, was to uncover all aspects of autochthonous biofilm pertaining to the formation of numerous deterioration symptoms occurring on the limestone Rozanec Mithraeum monument in Slovenia. Using state-of-the-art sequencing technologies combining mycobiome data with observations made via numerous light and spectroscopic (FTIR and Raman) microscopy analyses pointed out to epilithic lichen Gyalecta jenensis and its photobiont, carotenoid-rich Trentepohlia aurea, as the origin of salmon-hued pigmented alterations of limestone surface. Furthermore, the development of the main deterioration symptom on the monument, i.e., biopitting, was instigated by the formation of typical endolithic thalli and ascomata of representative Verrucariaceae family (Verrucaria sp.) in conjunction with the oxalic acid-mediated dissolution of limestone. The domination of lichenized fungi, as the main deterioration agents, both on the relief and surrounding limestone, was additionally supported by the high relative abundance of lichenized and symbiotroph groups in FUNGuild analysis. Obtained results not only upgraded knowledge of this frequently occurring but often overlooked group of extremophilic stone heritage deteriogens but also provided a necessary groundwork for the development of efficient biocontrol formulation applicable in situ for the preservation of similarly affected limestone monuments.


Assuntos
Biofilmes , Carbonato de Cálcio , Líquens , Líquens/microbiologia , Líquens/fisiologia , Eslovênia , Ascomicetos/fisiologia , Micobioma
5.
Environ Geochem Health ; 46(7): 244, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851657

RESUMO

HIGHLIGHTS: Microplastics (MPs) and microrubbers (MRs) determined in lichens and mosses around Shiraz. In lichens, MPs mainly thin fibres up to 1 MP g-1; MRs were < 0.1 MP g-1. In mosses, abundances were similar but with a greater fraction of larger, non-fibrous particles. Larger MPs and MRs decreased in abundance with distance and elevation from Shiraz. Around Shiraz, the common moss, Grimmia critina, would be the most suitable biomonitor. Lichens and mosses have been employed as biomonitors of atmospheric particulate pollutants, like metals and industrial solids, for many decades. Here, we evaluated the potential of nine species of crustose and foliose lichens and a widely distributed moss (Grimmia critina) to act as biomonitors of airborne microplastics (MPs) and microrubbers (MRs). About 200 lichens and 40 mosses were sampled across different altitudinal transects in the vicinity of Shiraz City, southwest Iran, and MPs and MRs were quantified and characterised after sample peroxidation. In most species of lichen, MP and MR abundance overall was < 1 g-1 and < 0.1 g-1, respectively, and the majority of plastics were fibres of < 10 µm in diameter and < 1000 µm in length. Respective weight normalised abundances of MPs and MRs were similar in G. critina, but there were greater proportions of both larger (> 1000 µm) and non-fibrous particles among the MPs. In both lichens and moss, there was a greater number of larger MPs and MRs at locations closest to and at the same elevation as Shiraz than at more distant and elevated locations, suggesting an inverse relationship between particle size and distance travelled. Among the lichens, members of the genus Acarospora, with their areolated form, appeared to act as the most suitable biomonitors for MPs and MRs. Overall, however, the wide distribution of the moss, G. crinita, and its ability to intercept and accumulate a broader range of sizes and shapes of MPs and MRs make this species a better choice, at least in the type of environment studied.


Assuntos
Poluentes Atmosféricos , Briófitas , Líquens , Microplásticos , Líquens/química , Irã (Geográfico) , Microplásticos/análise , Poluentes Atmosféricos/análise , Briófitas/química , Monitoramento Ambiental/métodos , Monitoramento Biológico/métodos , Tamanho da Partícula
6.
Sci Adv ; 10(24): eado2783, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875327

RESUMO

A core vulnerability in symbioses is the need for coordination between the symbiotic partners, which are often assumed to be closely physiologically integrated. We critically re-examine this assumed integration between symbionts in lichen symbioses, recovering a long overlooked yet fundamental physiological asymmetry in carbon balance. We examine the physiological, ecological, and transcriptional basis of this asymmetry in the lichen Evernia mesomorpha. This carbon balance asymmetry depends on hydration source and aligns with climatic range limits. Differences in gene expression across the E. mesomorpha symbiosis suggest that the physiologies of the primary lichen symbionts are decoupled. Furthermore, we use gas exchange data to show that asymmetries in carbon balance are widespread and common across evolutionarily disparate lichen associations. Using carbon balance asymmetry as an example, we provide evidence for the wide-ranging importance of physiological asymmetries in symbioses.


Assuntos
Líquens , Simbiose , Líquens/fisiologia , Líquens/metabolismo , Carbono/metabolismo , Ecossistema
7.
Environ Microbiol Rep ; 16(3): e13289, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38923181

RESUMO

The Lobaria pulmonaria holobiont comprises algal, fungal, cyanobacterial and bacterial components. We investigated L. pulmonaria's bacterial microbiome in the adaptation of this ecologically sensitive lichen species to diverse climatic conditions. Our central hypothesis posited that microbiome composition and functionality aligns with subcontinental-scale (a stretch of ~1100 km) climatic parameters related to temperature and precipitation. We also tested the impact of short-term weather dynamics, sampling season and algal/fungal genotypes on microbiome variation. Metaproteomics provided insights into compositional and functional changes within the microbiome. Climatic variables explained 41.64% of microbiome variation, surpassing the combined influence of local weather and sampling season at 31.63%. Notably, annual mean temperature and temperature seasonality emerged as significant climatic drivers. Microbiome composition correlated with algal, not fungal genotype, suggesting similar environmental recruitment for the algal partner and microbiome. Differential abundance analyses revealed distinct protein compositions in Sub-Atlantic Lowland and Alpine regions, indicating differential microbiome responses to contrasting environmental/climatic conditions. Proteins involved in oxidative and cellular stress were notably different. Our findings highlight microbiome plasticity in adapting to stable climates, with limited responsiveness to short-term fluctuations, offering new insights into climate adaptation in lichen symbiosis.


Assuntos
Clima , Líquens , Microbiota , Líquens/microbiologia , Líquens/fisiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Simbiose , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Fungos/fisiologia , Estações do Ano , Genótipo
8.
An Acad Bras Cienc ; 96(2): e20230657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38896692

RESUMO

Lichens are symbiotic associations of algae and fungi. They are edible as food and have been used in traditional medicine for years. It is aimed to screen Peltigera praetextata (Flörke ex Sommerf.) Zopfand and Peltigera elisabethae Gyeln. phytochemically by LC/QTOF/MS and according to the constituents to evaluate the antioxidant, tyrosinase inhibitory, and antibacterial activities. In total 54 of metabolites detected by LC/QTOF/MS were common in both species. According to LC/QTOF/MS scanning results, alkaloids, iridoid glycosides, phenolics, cyanogenetic glycosides, and terpenic structures were detected. DPPH, ABTS, superoxide radical scavenging activities, and metal chelating capacity IC50 values were 84.55, 9.349; 51.27, 9.127; 95.01, 58.65 and 20.57, 70.08 µg/mL., respectively. The CUPRAC reducing power was determined as 4.69 and 9.57 TEACCUPRAC, respectively. Tyrosinase inhibitor activity were found to be 86.95 and 196.7 µg/mL. Both lichens did not show antimicrobial effects. As a result of the antioxidant and tyrosinase inhibitor activities it was seen that their activities were significant and further in vivo studies could be carried out on this lichens.


Assuntos
Antioxidantes , Líquens , Compostos Fitoquímicos , Líquens/química , Antioxidantes/farmacologia , Antioxidantes/análise , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Antibacterianos/farmacologia , Antibacterianos/análise , Antibacterianos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos
9.
Nat Commun ; 15(1): 4452, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789482

RESUMO

Mutualistic symbioses have contributed to major transitions in the evolution of life. Here, we investigate the evolutionary history and the molecular innovations at the origin of lichens, which are a symbiosis established between fungi and green algae or cyanobacteria. We de novo sequence the genomes or transcriptomes of 12 lichen algal symbiont (LAS) and closely related non-symbiotic algae (NSA) to improve the genomic coverage of Chlorophyte algae. We then perform ancestral state reconstruction and comparative phylogenomics. We identify at least three independent gains of the ability to engage in the lichen symbiosis, one in Trebouxiophyceae and two in Ulvophyceae, confirming the convergent evolution of the lichen symbioses. A carbohydrate-active enzyme from the glycoside hydrolase 8 (GH8) family was identified as a top candidate for the molecular-mechanism underlying lichen symbiosis in Trebouxiophyceae. This GH8 was acquired in lichenizing Trebouxiophyceae by horizontal gene transfer, concomitantly with the ability to associate with lichens fungal symbionts (LFS) and is able to degrade polysaccharides found in the cell wall of LFS. These findings indicate that a combination of gene family expansion and horizontal gene transfer provided the basis for lichenization to evolve in chlorophyte algae.


Assuntos
Clorófitas , Líquens , Filogenia , Simbiose , Líquens/genética , Líquens/microbiologia , Simbiose/genética , Clorófitas/genética , Transferência Genética Horizontal , Evolução Molecular , Evolução Biológica , Transcriptoma , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Genômica
10.
Int J Mol Sci ; 25(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38791538

RESUMO

Various studies have shown that Hypogymnia physodes are a source of many biologically active compounds, including lichen acids. These lichen-specific compounds are characterized by antioxidant, antiproliferative, and antimicrobial properties, and they can be used in the cosmetic and pharmaceutical industries. The main aim of this study was to optimize the composition of natural deep eutectic solvents based on proline or betaine and lactic acid for the extraction of metabolites from H. physodes. The design of the experimental method and the response surface approach allowed the optimization of the extraction process of specific lichen metabolites. Based on preliminary research, a multivariate model of the experiment was developed. For optimization, the following parameters were employed in the experiment to confirm the model: a proline/lactic acid/water molar ratio of 1:2:2. Such a mixture allowed the efficient extraction of three depsidones (i.e., physodic acid, physodalic acid, 3-hydroyphysodic acid) and one depside (i.e., atranorin). The developed composition of the solvent mixtures ensured good efficiency when extracting the metabolites from the thallus of H. physodes with high antioxidant properties.


Assuntos
Depsídeos , Lactonas , Depsídeos/química , Depsídeos/isolamento & purificação , Depsídeos/farmacologia , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Solventes Eutéticos Profundos/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Prolina/química , Líquens/química , Ácido Láctico/química , Química Verde/métodos , Betaína/química , Betaína/análogos & derivados , Betaína/farmacologia , Solventes/química , Dibenzoxepinas , Hidroxibenzoatos
11.
Artigo em Inglês | MEDLINE | ID: mdl-38713186

RESUMO

Two novel actinobacteria, designated as LP05-1T and LP11T, were isolated from the lichen Pyxine cocoes (Sw.) Nyl. collected in Bangkok, Thailand. Genotypic and phenotypic analyses revealed that both strains represented members of the genus Streptomyces. The 16S rRNA gene of LP05-1T showed the highest similarity to the genome of Streptomyces gelaticus (98.41 %), while the 16S rRNA gene of LP11T was most similar to that of Streptomyces cinerochromogenes (98.93 %). The major menaquinones in LP05-1T were MK-9(H8), MK-9(H6), MK-9(H4) and MK-9(H2), and in LP11T, they were MK-9(H8) and MK-9(H6). Both strains exhibited the major fatty acids iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0, with LP05-1T also possessing iso-C17 : 0. The polar lipids of LP05-1T included phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified lipid, while those of LP11T consisted of phosphatidylethanolamine, lyso-phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified aminolipid and an unidentified glycolipid. The digital DNA-DNA hybridisation (dDDH) and average nucleotide identity (ANI) values indicated that both strains are distinct from each other with values below 70 and 95 %, respectively. dDDH, ANI by blast (ANIb) and ANI by MUMmer (ANIm) values between LP05-1T and its closely related type strains were 26.07-26.80 %, 81.24-82.01 % and 86.82-86.96 %, respectively, while those for LP11T and its closely related type strains were 30.70-31.70 %, 84.09-85.31 % and 88.02-88.39 %, respectively. The results of the taxonomic investigation, including dDDH and ANI values, indicate that LP05-1T and LP11T are novel type strains of two novel species within the genus Streptomyces. The names proposed are Streptomyces pyxinae sp. nov. for strain LP05-1T (=TBRC 15494T, =NBRC 115434T) and Streptomyces pyxinicus sp. nov. for strain LP11T (=TBRC 15493T, =NBRC 115421T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Líquens , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Streptomyces , Vitamina K 2 , Vitamina K 2/análogos & derivados , RNA Ribossômico 16S/genética , Líquens/microbiologia , Vitamina K 2/análise , DNA Bacteriano/genética , Streptomyces/genética , Streptomyces/isolamento & purificação , Streptomyces/classificação , Ácidos Graxos/química , Tailândia , Hibridização de Ácido Nucleico , Fosfolipídeos
12.
Environ Sci Pollut Res Int ; 31(24): 35800-35810, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38740686

RESUMO

The number of atmospheric mercury (Hg) monitoring stations is growing globally. However, there are still many regions and locations where Hg monitoring is limited or non-existent. Expansion of the atmospheric Hg monitoring network could be facilitated by the use of cost-effective monitoring methods. As such, biomonitoring and passive monitoring offer a unique alternative to well-established monitoring by active measurements, since they do not require a power supply and require minimal workload to operate. The use of biomonitoring (lichens and mosses) and passive air samplers (PASs) (various designs with synthetic materials) has been reported in the literature, and comparisons with active measurement methods have also been made. However, these studies compared either biomonitoring or PASs (not both) to only one type of active measurement. In our work, we used transplanted (7 sampling sites) and in situ lichens (8 sampling sites) for biomonitoring, two PASs from different producers (3 sampling sites), and two different active measurement types (continuous and discontinuous active measurements, 1 and 8 sampling sites, respectively) to evaluate their effectiveness as monitoring methods. In the 9-month sampling campaign, 3 sampling locations with different characteristics (unpolluted, vicinity of a cement plant, and vicinity of a former Hg mine) were used. The results obtained with lichens and PASs clearly distinguished between sampling locations with different Hg concentrations; using both PASs and lichens together increased the confidence of our observations. The present work shows that biomonitoring and passive sampling can be effectively used to identify areas with elevated atmospheric Hg concentrations. The same can be said for discontinuous active measurements; however, the discrepancy between atmospheric Hg concentrations derived from PASs and discontinuous active measurements should be further investigated in the future.


Assuntos
Poluentes Atmosféricos , Monitoramento Biológico , Monitoramento Ambiental , Líquens , Mercúrio , Líquens/química , Mercúrio/análise , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Atmosfera/química
13.
Environ Int ; 187: 108707, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692149

RESUMO

Currently, natural and urban ecosystems are affected by different types of atmospheric deposition, which can compromise the balance of the environment. Plastic pollution represents one of the major threats for biota, including lichens. Epiphytic lichens have value as bioindicators of environmental pollution, climate change, and anthropic impacts. In this study, we aim to investigate the lichen bioaccumulation of airborne microplastics along an anthropogenic pollution gradient. We sampled lichens from the Genera Cladonia and Xanthoria to highlight the effectiveness of lichens as tools for passive biomonitoring of microplastics. We chose three sites, a "natural site" in Altipiani di Arcinazzo, a "protected site" in Castelporziano Presidential estate and an "urban site" in the centre of Rome. Overall, we sampled 90 lichens, observed for external plastic entrapment, melt in oxygen peroxide and analysed for plastic entrapment. To validate the method, we calculated recovery rates of microplastics in lichen. Particularly, 253 MPs particles were detected across the 90 lichen samples: 97 % were fibers, and 3 % were fragments. A gradient in the number of microplastic fibers across the sites emerged, with increasing accumulation of microplastics from the natural site (n = 58) to the urban site (n = 116), with a direct relationship between the length and abundance of airborne microplastic fibers. Moreover, we detected the first evidences of airborne mesoplastics entrapped by lichens. On average, the natural site experienced the shortest fibre length and the centre of Rome the longest. No differences in microplastics accumulation emerged from the two genera. Our results indicated that lichens can effectively be used for passive biomonitoring of microplastic deposition. In this scenario, the role of lichens in entrapping microplastics and protecting pristine areas must be investigated. Furthermore, considering the impact that airborne microplastics can have on human health and the effectiveness of lichens as airborne microplastic bioindicators, their use is encouraged.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Líquens , Microplásticos , Líquens/química , Microplásticos/análise , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Monitoramento Biológico/métodos , Cidades
14.
Curr Microbiol ; 81(7): 195, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809483

RESUMO

The endolichenic fungi are an unexplored group of organisms for the production of bioactive secondary metabolites. The aim of the present study is to determine the antibacterial potential of endolichenic fungi isolated from genus Parmotrema. The study is continuation of our previous work, wherein a total of 73 endolichenic fungi were isolated from the lichenized fungi, which resulted in 47 species under 23 genera. All the isolated endolichenic fungi were screened for preliminary antibacterial activity. Five endolichenic fungi-Daldinia eschscholtzii, Nemania diffusa, Preussia sp., Trichoderma sp. and Xylaria feejeensis, were selected for further antibacterial activity by disc diffusion method. The zone of inhibition ranged from 14.3 ± 0.1 to 23.2 ± 0.1. The chemical composition of the selected endolichenic fungi was analysed through GC-MS, which yielded a total of 108 compounds from all the selected five endolichenic fungi. Diethyl phthalate, 1-hexadecanol, dibutyl phthalate, n-tetracosanol-1, 1-nonadecene, pyrrol[1,2-a] pyrazine-1,4-dione, hexahydro-3-(2-methyl) and tetratetracontane were found to be common compounds among one or the other endolichenic fungi, which possibly were responsible for antibacterial activity. GC-MS data were further analysed through Principal Component Analysis which showed D. eschscholtzii to be with unique pattern of expression of metabolites. Compound confirmation test revealed coumaric acid to be responsible for antibacterial activity in D. eschscholtzii. So, the study proves that endolichenic fungi that inhabit lichenized fungal thalli could be a source of potential antibacterial compounds.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Metabolismo Secundário , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/metabolismo , Líquens/microbiologia , Líquens/química , Bactérias/efeitos dos fármacos , Bactérias/classificação , Bactérias/metabolismo , Ascomicetos/metabolismo , Ascomicetos/química , Cromatografia Gasosa-Espectrometria de Massas
15.
Environ Monit Assess ; 196(6): 545, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38740605

RESUMO

In Tunisia, urban air pollution is becoming a bigger problem. This study used a combined strategy of biomonitoring with lichens and satellite mapping with Sentinel-5 satellite data processed in Google Earth Engine (GEE) to assess the air quality over metropolitan Tunis. Lichen diversity was surveyed across the green spaces of the Faculty of Science of Tunisia sites, revealing 15 species with a predominance of pollution-tolerant genera. The Index of Atmospheric Purity (IAP) calculated from the lichen data indicated poor air quality. Spatial patterns of pollutants sulfur dioxide (SO2), ozone (O3), nitrogen dioxide (NO2), carbon monoxide (CO), and aerosol index across Greater Tunis were analyzed from Sentinel-5 datasets on the GEE platform. The higher values of these indices in the research area indicate that it may be impacted by industrial activity and highlight the considerable role that vehicle traffic plays in air pollution. The results of the IAP, IBL, and the combined ground-based biomonitoring and satellite mapping techniques confirm poor air quality and an environment affected by atmospheric pollutants which will enable proactive air quality management strategies to be put in place in Tunisia's rapidly expanding cities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Líquens , Ozônio , Dióxido de Enxofre , Líquens/química , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Tunísia , Ozônio/análise , Dióxido de Enxofre/análise , Dióxido de Nitrogênio/análise , Cidades , Imagens de Satélites , Monóxido de Carbono/análise
16.
Life Sci Space Res (Amst) ; 41: 191-201, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38670647

RESUMO

The cortical anthraquinone yellow-orange pigment parietin is a secondary lichen substance providing UV-shielding properties that is produced by several lichen species. In our work, the secondary metabolite has been extracted from air-dried thalli of Xanthoria parietina. The aims of this study were to characterize parietin absorbance through UV-VIS spectrophotometry and with IR spectroscopy and to evaluate its photodegradability under UV radiation through in situ reflectance IR spectroscopy to understand to what extent the substance may have a photoprotective role. This allows us to relate parietin photo-degradability to the lichen UV tolerance in its natural terrestrial habitat and in extreme environments relevant for astrobiology such as Mars. Extracted crystals were UV irradiated for 5.59 h under N2 flux. After the UV irradiation, we assessed relevant degradations in the 1614, 1227, 1202, 1160 and 755 cm-1 bands. However, in light of Xanthoria parietina survivability in extreme conditions such as space- and Mars-simulated ones, we highlight parietin UV photo-resistance and its relevance for astrobiology as photo-protective substance and possible bio-hint.


Assuntos
Emodina/análogos & derivados , Exobiologia , Líquens , Raios Ultravioleta , Líquens/efeitos da radiação , Líquens/química , Fotólise , Espectrofotometria Infravermelho
17.
Ying Yong Sheng Tai Xue Bao ; 35(3): 739-748, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646762

RESUMO

Biological soil crust (biocrust) is widely distributed on the Loess Plateau and plays multiple roles in regulating ecosystem stability and multifunctionality. Few reports are available on the distribution characteristics of biocrust in this region, which limits the assessment of its ecological functions. Based on 388 sampling points in different precipitation zones on the Loess Plateau from 2009 to 2020, we analyzed the coverage, composition, and influencing factors of biocrust across different durations since land abandonment, precipitation levels, topography (slope aspect and position), and utilization of abandoned slopelands (shrubland, forest, and grassland). On this base, with the assistance of machine learning and spatial modeling methods, we generated a distribution map of biocrust and its composition at a resolution of 250 m × 250 m, and analyzed the spatial distribution of biocrust on the Loess Plateau. The results showed that the average biocrust coverage in the woodlands and grasslands was 47.3%, of which cyanobacterial crust accounted for 25.5%, moss crust 19.7%, and lichen crust 2.1%. There were significant temporal and spatial variations. Temporally, the coverage of biocrust in specific regions fluctuated with the extension of the abandoned durations and coverage of cyanobacterial crust, while moss crust showed a reverse pattern. In addition, the coverage of biocrust in the wet season was slightly higher than that in the dry season within a year. Spatially, the coverage of biocrusts on the sandy lands area on the Loess Plateau was higher and dominated by cyanobacterial crusts, while the coverage was lower in the hilly and gully area. Precipitation and utilization of abandoned land were the major factors driving biocrust coverage and composition, while slope direction and position did not show obvious effect. In addition, soil organic carbon content, pH, and texture were related to the distribution of biocrust. This study uncovered the spatial and temporal variability of biocrust distribution, which might provide important data support for the research and management of biocrust in the Loess Plateau region.


Assuntos
Ecossistema , Florestas , Líquens , Solo , Análise Espaço-Temporal , China , Solo/química , Líquens/crescimento & desenvolvimento , Pradaria , Cianobactérias/crescimento & desenvolvimento , Microbiologia do Solo , Altitude , Monitoramento Ambiental , Briófitas/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento
18.
Mol Biol Rep ; 51(1): 549, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38642168

RESUMO

BACKGROUND: Lichen is a symbiotic association of algae and fungi, recognized as a self-sustaining ecosystem that constitutes an indeterminant number of bacteria, actinomycetes, fungi, and protozoa. We evaluated the endolichenic fungal assemblage given the dearth of knowledge on endolichenic fungi (ELFs), particularly from part of the Central Western Ghats, Karnataka, and conducted a phylogenetic analysis of xylariaceous fungi, the most diversified group of fungi using ITS and ITS+Tub2 gene set. RESULTS: Out of 17 lichen thalli collected from 5 ecoregions, 42 morphospecies recovered, belong to the class Sordariomycetes, Eurotiomycetes, Dothideomycetes, Leotiomycetes, Saccharomycetes. About 19 and 13 ELF genera have been reported from Parmotrema and Heterodermia thallus. Among the ecoregions EC2 showing highest species diversity (Parmotrema (1-D) = 0.9382, (H) = 2.865, Fisher-α = 8.429, Heterodermia (1-D) = 0.8038, H = 1.894, F-α = 4.57) followed the EC3 and EC1. Xylariales are the predominant colonizer reported from at least one thallus from four ecoregions. The morphotypes ELFX04, ELFX05, ELFX08 and ELFX13 show the highest BLAST similarity (> 99%) with Xylaria psidii, X. feejeensis, X. berteri and Hypoxylon fragiforme respectively. Species delimitation and phylogenetic position reveal the closest relation of Xylariaceous ELFs with plant endophytes. CONCLUSIONS: The observation highlights that the deciduous forest harness a high number of endolichenic fungi, a dominant portion of these fungi are non-sporulating and still exist as cryptic. Overall, 8 ELF species recognized based on phylogenetic analysis, including the two newly reported fungi ELFX03 and ELFX06 which are suspected to be new species based on the present evidence. The study proved, that the lichen being rich source to establish fungal diversity and finding new species. Successful amplification of most phylogenetic markers like RPB2, building of comprehensive taxonomic databases and application of multi-omics data are further needed to understand the complex nature of lichen-fungal symbiosis.


Assuntos
Líquens , Parmeliaceae , Líquens/microbiologia , Filogenia , Ecossistema , Índia , Plantas/microbiologia
19.
Methods Mol Biol ; 2744: 517-523, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38683339

RESUMO

This rapid, equipment-free DNA isolation procedure using chromatography paper is a simple method that can be performed in less than 30 min and requires no wet lab experience. With minimal expense, it offers an affordable alternative for anyone wanting to explore biodiversity. It also provides an excellent option for use in classrooms or other activities that are time limited. The method works best for plants or lichens, producing stable DNA on Whatman® chromatography paper at room temperature, which can be eluted as needed.


Assuntos
Código de Barras de DNA Taxonômico , Código de Barras de DNA Taxonômico/métodos , DNA/isolamento & purificação , DNA/genética , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Plantas/genética , Cromatografia/métodos , Líquens/genética
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