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Bioassay-guided fractionation of the ethyl acetate extract of Phanerochaete sordida, an endolichenic fungus (ELF) isolated from the host lichen Bactrospora myriadea, collected from Negombo lagoon, Sri Lanka, led to the isolation of a bioactive compound. Following the identification of the fungus using morphological and DNA barcoding techniques, the pure compound was isolated using column chromatography, preparative TLC, and semipreparative HPLC. The structure elucidation was carried out using IR, HR-ESI-MS and 1H, 13C & 2D NMR spectroscopic methods. The in vitro bioassays conducted revealed that compound 1 has a high antioxidant activity with ABTS•+ (IC50 58.91 ± 1.35 μ M), moderate anti-inflammatory activity (IC50 254.79 ± 1.41 μ M), comparable antibacterial activity against the oral-bacterial strain Streptococcus mutans (MIC 898.79 μM and MLC 1797.58 μM), moderate tyrosinase inhibition (IC50 1713.69 ± 8.65 μ M), and moderate cytotoxicity against oral cancer (IC50 13.65 ± 0.02 μ M), in comparison with respective positive controls. The in silico experiments conducted for tyrosinase inhibition and cytotoxicity using Schrödinger revealed results in line with the in vitro results, thus confirming the bioactivities. The molecule also satisfies the key features of drug likeliness according to pharmacokinetic studies. [ABSTRACT FROM AUTHOR]

Endolichenic fungi (ELF) serve as a novel source of natural products with distinctive bioactivities. A total of 58 ELF isolated from 29 lichens collected from mangrove and mangrove-associated plants of Negombo lagoon, Sri Lanka were identified using morphological and DNA barcoding techniques. Ethyl acetate extracts of 18 such identified ELF isolates were subjected to in vitro assays to determine antioxidant, anti-inflammatory, tyrosinase inhibitory and antibacterial potency. Liquid chromatography–mass spectrometry (LC–MS) dereplication was conducted on the crude extracts in order to detect the secondary metabolites present. The extracts of Daldinia eschscholtzii and Hypoxylon lividipigmentum had the highest radical scavenging activity with SC50 values 14.27 ±0.24 µg/mL and 18.34±1.37 µg/mL, respectively. D. eschscholtzii also exhibited remarkable anti-inflammatory activity (IC50 7.97 ±0.09 µg/mL). Tyrosinase inhibitory activity was highest in Cytospora xylocarpi (IC50 68.50 ±0.34 µg/mL), while the highest activity against aerobic bacterial species Escherichia coli, Bacillus subtilis, Staphylococcus aureus and the anaerobic bacterial strain Streptococcus mutans was observed in the extracts of Xylaria feegenesis and Curvularia lunata. After a thorough study of the LC–MS profiles, it was found that the chemical profiles of Neofusicoccum occulatum, H. lividipigmentum and Myramaececium rubricosum were previously poorly explored in the literature. [ABSTRACT FROM AUTHOR]

Corticolous lichens in the central mountains of Sri Lanka differ with vegetation type, disturbance and climate. All growth forms of lichens were studied in 42 plots (six plots × seven vegetation types), yielding 124 species. Lichen species diversity varied with number of tree species per plot (correlations) and differed with disturbance group, vegetation type and climate zone (general linear models). Lichen community composition (estimated cover of 74 species each at ≥ 3 plots) varied along two ordination gradients secondarily correlated with disturbance (nonmetric multidimensional scaling, NMS). Undisturbed and disturbed plots (mostly grouped by vegetation type) were divided along NMS axis 1, correlating with distance to undisturbed forest. Longest-disturbed plots differed from all others along NMS axis 2 and were correlated with canopy cover. Climate was weakly reflected on the ordination as the proximity of two plot clusters in montane vegetation types. Indicator species analyses (ISA) of lichen cover by plot identified 60 strong indicator species (indicator value ≥ 50%, P < 0.015). Fifty-seven species were indicators for individual vegetation types (28 of them for undisturbed types); three were for a disturbance group only; 11 were also for a disturbance group or climate zone. Most species strongly driving ordination patterns were also ISA indicators. Most lichens were crustose (39, with 24 in the Graphidaceae). Each vegetation type had at least one indicator with trentepohliod algae (increasing for undisturbed plots) and one with chlorococcoid algae. Two visually distinct indicator species, three genera and two multi-genus groups will be useful to parataxonomists in forest evaluation. [ABSTRACT FROM AUTHOR]

We provide an updated survey for Sri Lanka of species of Graphis sensu Staiger, recently divided into Graphis s. str. and Allographa , including brief descriptions and a key to all 124 species currently known. Six new species are described: Allographa bambusicola Weerakoon, Lücking & Aptroot, a bambusicolous Allographa with entire labia, a laterally carbonized excipulum, 80–100 × 15–17 µm large, muriform ascospores and a rather thick, irregularly verrucose lateral thalline margin of the lirellae; A. weerasooriyana Weerakoon, Arachchige & Lücking, a corticolous Allographa resembling A. rustica Kremp. in overall anatomy and chemistry, but with a verrucose thalline margin of the lirellae and labia not distinctly raised above the thalline margin; Graphis flosculifera Weerakoon, Lücking & Aptroot, a corticolous Graphis resembling G. insulana but differing in the unique disposition of the lirellae and the slightly more elongate ascospores; G. rajapakshana Weerakoon, Lücking & Aptroot, a corticolous Graphis resembling G. desquamescens , including in ascospore size, but with lirellae with a distinct lateral thalline margin; G. rimosothallina Weerakoon, Lücking & Aptroot, a corticolous Graphis with a thick, uneven, rimose thallus and Fissurina -like lirellae, a completely carbonized excipulum and transversely 7-septate ascospores, 32–37 × 8–10 µm; and G. thunsinhalayensis Weerakoon, Arachchige & Lücking, a corticolous Graphis resembling G. subalbostriata but with smaller ascospores and lacking white lines between the striae of the labia. We also validate the name G. verrucoserpens Lücking. A total of 106 species are reported here for the first time from Sri Lanka. A biogeographical comparison with two other well-sampled countries (Costa Rica and Thailand) revealed a significantly higher similarity in species composition with Costa Rica than between Thailand and Costa Rica, suggesting a potential signature of the 'biotic ferry' hypothesis, that is the migration of lineages from Gondwana (partly corresponding to the modern Neotropics) via the north-eastwards drifting Indian subcontinent and subsequent interchange with Laurasia (partly corresponding to the modern eastern Paleotropics). However, the evolutionary timeline of the clades involved does not support this hypothesis and suggests an alternative explanation of geologically more recent mid- to long-distance dispersal. [ABSTRACT FROM AUTHOR]

The genus Graphis sensu Staiger was recently divided into two genera, Graphis s. str. and Allographa. The latter contains mostly species with robust lirellae with a well-developed, often massively carbonized excipulum. With one exception, it also contains all species with a pigmented, yellow to orange pruina on the lirellae. Until now, seven species of Allographa were known with this character, all present in the Neotropics and one also in Africa. Here we describe two further species, both from tropical Asia, thus extending the known distribution of Allographa species with pigmented lirellae to the entire tropics. Allographa kamojangensis Jatnika, Noer & Lücking sp. nov. from Indonesia (Java) was recognized as a new taxon on the social media Facebook site Lichens Connecting People. Detailed studies showed that it deviates from the neotropical A. firferi in the much larger ascospores and the orange, K+ immediately purple-violet pigment, and from A. lutea in the completely carbonized excipulum and the larger ascospores. Allographa jayatilakana Weerakoon, Arachchige & Lücking sp. nov. was discovered in the second author's backyard during a recent inventory of Graphidaceae in Sri Lanka. It differs from A. flavominiata in the much shorter ascospores, from A. firferi in the terminally muriform ascospores, and from A. ochracea in the yellow-orange, K+ yellow then slowly purple-violet pruina. A key is presented to all nine species of Allographa with pigmented lirellae. [ABSTRACT FROM AUTHOR]

Two hundred and seven lichen species are newly reported from Sri Lanka, eight of which were previously thought to be endemic in India; 91 species are new to the Indian subcontinent, and four to Asia, and three are described here as new to science: Astrothelium nitidulum which has 7-septate ascospores with diamond-shaped lumina, mostly simple ascomata in shiny olive pseudostromata and an inspersed hamathecium; Heterodermia queensberryi which is similar to Heterodermia propagulifera but with a corona of lobules around the apothecia; and Malmidea papulosa, which is similar to Malmidea granifera but has regular warts and lacks medulla in the excipulum. [ABSTRACT FROM AUTHOR]

Pyrenulaceae is one of the dominant lichen families in the tropics, especially in lowland evergreen forests. Although very species-rich, phylogenetic relationships within Pyrenulaceae have not been extensively studied using molecular data, and its morphology-based generic delimitation remains untested. A recent lichenological survey carried out in the Knuckles Mountain Range in Sri Lanka allowed the first author to collect fresh specimens of different species of Pyrenula, and to investigate the phylogenetic relationships within the family Pyrenulaceae using a multigene analysis (ITS, nuLSU and mtSSU) and a preliminary dataset of 21 taxa. This data shows that the family Pyrenulaceae can be divided into two well-supported groups and suggests that the genus Pyrenula is not monophyletic. Characters usually used for generic classification in this family (ascospore colour and septation, structure of the ascospore locules, secondary chemistry, hamathecium structure, ostiole position) do not correlate with these two groups. However, the presence of pseudocyphellae is restricted to species of Pyrenula from one group. [ABSTRACT FROM AUTHOR]

Three new species of Chapsa in the family Graphidaceae are described from tropical Asia. Chapsa mastersonii Rivas Plata, Lumbsch & Lücking from the Philippines is characterized by large apothecia with thickly white-pruinose discs, large, muriform, non-amyloid ascospores, and the stictic acid chemosyndrome. Chapsa wijeyaratniana Weerakon, Lumbsch & Lücking from Sri Lanka has apothecia similar to the preceding species but forms an ecorticate thallus with maculiform to capitate soralia, has small, submuriform ascospores, and lacks secondary substances. Chapsa wolseleyana Weerakon, Lumbsch & Lücking forms apothecia with red to pinkish or purplish red discs and large, muriform ascospores becoming pale brown. [ABSTRACT FROM AUTHOR]

Six new species of Graphidaceae are described from Sri Lanka, four in Graphis sensu Staiger and one each in Fissurina and Thelotrema. Fissurina srilankensis Weerakoon, Wijeyaratne & Lacking is characterized by lirellae with well-developed labia and comparatively large, muriform ascospores. Graphis allugallenensis Weerakoon, Wijeyaratne & Lacking is similar to G. vittata but has a distinctly verrucose thalline margin along the lirellae. Graphis dotalugalensis Weerakoon, Wijeyaratne & Rivas Plata resembles G. proserpens in the exposed lirellae with striate labia and apically carbonized excipulum but differs in the comparatively large ascospores. Graphis knucklensis Weerakoon, Wijeyaratne & Wolseley features lirellae with striate labia, an inspersed hymenium, and norstictic acid as secondary compound. Graphis srilankensis Weerakoon, Wijeyaratne & Lumbsch has entire labia with a completely carbonized excipulum, inspersed hymenium, transversely septate ascospores, and produces norstictic acid. Finally, Thelotrema pseudosimilans Weerakoon, Wijeyaratne & Lumbsch is close to T. similans in the corticate thallus and prominent apothecia with narrow pore, but has consistently larger ascospores. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) pollution has emerged as a major cause of concern as atmospheric concentrations continue to increase globally. Environmentally damaging NH 3 levels are expected to severely affect sensitive and economically important organisms, but evidence is lacking in many parts of the world. We describe the design and operation of a wind-controlled NH 3 enhancement system to assess effects on forests in two contrasting climates. We established structurally identical NH 3 enhancement systems in a temperate birch woodland in the UK and a tropical sub-montane forest in central Sri Lanka, both simulating real-world NH 3 pollution conditions. Vertical and horizontal NH 3 concentrations were monitored at two different time scales to understand NH 3 transport within the forest canopies. We applied a bi-directional resistance model with four canopy layers to calculate net deposition fluxes. At both sites, NH 3 concentrations and deposition were found to decrease exponentially with distance away from the source, consistent with expectations. Conversely, we found differences in vertical mixing of NH 3 between the two experiments, with more vertically uniform NH 3 concentrations in the dense and multi-layered sub-montane forest canopy in Sri Lanka. Monthly NH 3 concentrations downwind of the source ranged from 3 to 29 μg m−3 at the UK site and 2–47 μg m−3 at the Sri Lankan site, compared with background values of 0.63 and 0.35 μg m−3, respectively. The total calculated NH 3 dry deposition flux to all the canopy layers along the NH 3 transects ranged from 12 to 162 kg N ha−1 yr−1 in the UK and 16–426 kg N ha−1 yr−1 in Sri Lanka, representative of conditions in the vicinity of a range of common NH 3 sources. This multi-layer model is applicable for identifying the fate of NH 3 in forest ecosystems where the gas enters the canopy laterally through the trunk space and exposes the understorey to high NH 3 levels. In both study sites, we found that cuticular deposition was the dominant flux in the vegetation layers, with a smaller contribution from stomatal uptake. The new facilities are now allowing the first ever field comparison of NH 3 impacts on forest ecosystems, with special focus on lichen bio-indicators, which will provide vital evidence to inform NH 3 critical levels and associated nitrogen policy development in South Asia. [Display omitted] • Wind-controlled field NH 3 release systems replicate real-world pollution scenarios and are a tool for assessing ecological impacts of NH 3. • Our resistance model aids quantifying NH 3 deposition to different layers of a forest canopy from an NH 3 source located within the canopy. • The NH 3 release system coupled with the resistance model shows that soil surface and leaf cuticles experience the highest NH 3 deposition. [ABSTRACT FROM AUTHOR]

Endolichenic fungi (ELF) are unexplored group of organisms as a source for the production of bioactive secondary metabolites with radical scavenging activity, antilipase and amylase inhibitory activities. Endolichenic fungi in lichens collected from mangrove or mangrove associated plants are least known for their fungal diversity and potential to produce bioactive compounds. A total of 171 ELF strains were isolated from the lichens collected from mangrove and mangrove associated plants in Puttalam lagoon. Out of this collection, 70 isolates were identified using rDNA-ITS region sequence homology to the GenBank accessions and a phylogenetic analysis was performed. Commonly isolated genera of ELF from lichens were Aspergillus, Byssochlamys, Talaromyces, Diaporthe, Phomopsis, Endomelanconiopsis, Schizophyllum, Cerrena, Trichoderma, Xylaria, Hypoxylon, Daldinia, Preussia, Sordaria, Neurospora, and Lasiodiplodia. In the present study, the effectiveness of ethyl acetate extracts of the ELF isolates were investigated against antioxidant activity, antilipase activity and α-amylase inhibition activity in in-vitro conditions. The results revealed that the extracts of Daldinia eschscholtzii, Diaporthe musigena and Sordaria sp. had the highest radical scavenging activity with smaller IC50 values (25 μg/mL to 31 μg/mL) compared to the IC50 values of BHT (76.50±1.47 μg/mL). Antilipase assay revealed that 13 extracts from ELF showed promising antiobesity activity ranged between 25% to 40%. Amylase inhibitory assay indicated that the test extracts do not contain antidiabetic secondary metabolites., Competing Interests: The authors have declared that no competing interests exist.