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The richness, composition, abundance, and correlation with the atmospheric oxide concentrations of the community of corticolous lichens in the urban and peri-urban areas of the city of Ibagué (Colombia) were evaluated, selecting 25 individuals of the four most abundant phorophyte species. Twenty-nine lichen taxa grouped in 13 families and 17 genera were recorded, with a higher lichen coverage and taxa richness in the urban area. A non-metric multidimensional scaling (NMDS) analysis showed the conformation of two lichen communities associated with the urban and peri-urban areas of the city, and variation in composition among the phorophyte species. Exclusive and indicator taxa were found for both zones, as well as associations between variables through the application of a general linear model. Higher concentrations of atmospheric gases CO, SO2, NO2, and O3 were found in the urban zone, and positive/negative relationships with some lichen taxa. There is high variability in the response of the lichen assemblage of urban and peri-urban ecosystems to environmental effects, with substantial or minimal changes in the variables of richness, coverage, and phorophyte association, and according to their interaction with atmospheric oxides, the patterns of potential tolerant and/or sensitive species are formed for their implementation in bioindication studies. [ABSTRACT FROM AUTHOR]

The lichen species Cladonia chlorophaea and C. gracilis (Cladoniaceae) are widely distributed in the island archipelago of maritime Antarctica and represent a natural resource of scientific interest. In this work, the metabolomic characterization of the ethanolic extracts of these species and the determination of the antioxidant activity, enzymatic inhibition and anti-inflammatory potential of selected compounds on the 5-lipoxygenase enzyme by molecular docking and cytoprotective activity in the SH-SY5Y cell line were carried out. Nineteen compounds were identified by liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-ESI-QTOF-MS) in each of the species. The contents of phenolic compounds, antioxidant activity, the inhibition of cholinesterases (acetylcholinesterase and butyrylcholinesterase) and digestive enzymes (α-glucosidase and pancreatic lipase) were variable among species, with better results in C. chlorophaea. Molecular docking evidenced significant binding affinities of some compounds for the 5-lipoxygenase enzyme, together with outstanding pharmacokinetic properties. Both extracts were shown to promote cell viability and a reduction in reactive oxygen species production in an H2O2-induced oxidative stress model. This study contributes to the chemical knowledge of the Cladonia species and demonstrates the biological potential for the prevention and promising treatment of central nervous system pathologies, inflammatory disorders and metabolic alterations. [ABSTRACT FROM AUTHOR]

The lichen species Lecania brialmontii, Pseudephebe pubescens, and Sphaerophorus globosus are part of the prominent lichenoflora of the Antarctic territory. In this work, we report the metabolomic identification of ethanolic extracts of these species, their antioxidant and cholinesterase enzyme inhibitory activity, and conduct a molecular docking analysis with typical compounds. Eighteen compounds were identified by UHPLC-ESI-QTOF-MS in L. brialmontii, 18 compounds in P. pubescens, and 14 compounds in S. globosus. The content of phenolic compounds was variable among the species, ranging from 0.279 to 2.821 mg AG/g, and all three species showed high inhibition potential on the cholinesterase enzymes. Molecular docking showed important interactions between AChE and BChE with the selected compounds. This study evidences the chemical fingerprint of three species of the order Lecanorales that support the continuation of the study of other biological activities and their potential for medical research. [ABSTRACT FROM AUTHOR]

Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria. Lichens belonging to the Parmeliaceae family comprise 2700 species of lichens, including the Parmotrema genus which is composed of 300 species. The metabolites of this genus include depsides, depsidones, phenolics, polysaccharides, lipids, diphenylethers and dibenzofurans, which are responsible for the biological activities reported including antidiabetic, antihelmintic, anticancer, antioxidant, antibacterial, anti-inflammatory, antimitotic, antitumoral, antifungal, and antioxidant enzyme inhibitory. Due to scarce knowledge of metabolomic profiles of Parmotrema species (P. andinum and P. robustum), a full metabolome study based on ultra-high performance liquid chromatography- diode array detector-electrospray ionization-quadrupole-orbitrap-mass-spectrometry (UHPLC-DAD-ESI-Q-orbitrap MS) was performed for a comprehensive characterization of their substances. From the methanolic extracts of these species, a total of 54 metabolites were identified for the first time using this hyphenated technique, including thirty compounds in P. andinum, and thirty-seven in P. robustum. Moreover, two compounds were not identified as known compounds, and could be new structures, according to our data. This report shows that this technique is effective and accurate for rapid chemical identification of lichen substances and the compounds identified could serve as chemotaxonomic markers to differentiate these ruffle lichens. [ABSTRACT FROM AUTHOR]

Eleven species of lichens of the genus Sticta, ten of which were collected in Colombia (S. pseudosylvatica S. luteocyphellata S. cf. andina S. cf. hypoglabra, S. cordillerana, S. cf. gyalocarpa S. leucoblepharis, S. parahumboldtii S. impressula, S. ocaniensis) and one collected in Chile (S. lineariloba), were analyzed for the first time using hyphenated liquid chromatography with high-resolution mass spectrometry. In the metabolomic analysis, a total of 189 peaks were tentatively detected; the analyses were divided in five (5) groups of compounds comprising lipids, small phenolic compounds, saturated acids, terpenes, and typical phenolic lichen compounds such as depsides, depsidones and anthraquinones. The metabolome profiles of these eleven species are important since some compounds were identified as chemical markers for the fast identification of Sticta lichens for the first time. Finally, the usefulness of chemical compounds in comparison to traditional morphological traits to the study of ancestor–descendant relationships in the genus was assessed. Chemical and morphological consensus trees were not consistent with each other and recovered different relationships between taxa. [ABSTRACT FROM AUTHOR]

Ovidia pillopillo (Lloime) is an endemic species of the Valdivian Forest of Chile. Little is known on the chemistry and biological activity of this plant. In this study, the phenolic profile, antioxidant capacities and enzyme inhibition capacities (against tyrosinase and cholinesterase) of the plant were investigated for the first time. The phenolic profile of the plant was obtained by UHPLC-MS fingerprinting with high resolution, which showed the presence of several flavonoids and coumarins. The antioxidant potential was measured by FRAP and ORAC (45.56 ± 1.32; 25.33 ± 1.2 μmol Trolox equivalents/g dry plant, respectively) plus ABTS and DPPH methods (IC50 = 9.95 ± 0.05 and 6.65 ± 0.5 μg/mL, respectively). Moreover, the flavonoid and phenolic contents were determined (57.33 ± 0.82 and 38.42 ± 1.32, μg of Trolox and quercetin equivalents/100 g dry weight, respectively). The ethanolic extract showed cholinesterase (IC50 = 1.94 ± 0.07 and 2.73 ± 0.05 μg/mL, for AChE and BuChE, respectively) and tyrosinase (4.92 ± 0.05 μg/mL) enzyme inhibition activities. Based on these in vitro studies, in silico simulations were performed, which determined that the major compounds as ligands likely docked in the receptors of the enzymes. These results suggest that Ovidia pillopillo produce interesting special coumarins and flavonoids, which are potential candidates for the exploration and preparation of new medicines. [ABSTRACT FROM AUTHOR]