Lichen Samples Research Articles

Selecting the species to be used in lichen transplant surveys of air pollution in Tunisia

This study was undertaken with the aim of selecting one or more lichen species that are the most suitable for transplant-based surveys of air pollution in Tunisia, in areas where the local native lichen vegetation is scanty or missing at all. To this purpose, four epiphytic (tree inhabiting) lichen species (Evernia prunastri, Flavoparmelia caperata, Parmotrema perlatum, Ramalina farinacea) were collected from the Babouch forests, a remote and unpolluted area of NW Tunisia, and analyzed for their content of potentially toxic elements (PTEs), namely Al, As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, and Zn, by ICP-MS. Moreover, also the physiological status of the lichen samples was evaluated by measuring their chlorophyll content, photosynthetic efficiency, and spectral reflectance. The results indicated a remarkable contribution of airborne soil and dust particles to the total PTE content, especially for the foliose species F. caperata and P. perlatum. The fruticose lichens E. prunastri and R. farinacea had a lower and similar content of PTEs, and hence were regarded as more suitable to be used in transplant studies, since are able to detect even minimal accumulation amounts. All lichen species were healthy, as emerged from the analysis of physiological parameters.

Bacterial microbiome in tropical lichens and the effect of the isolation method on culturable lichen-derived actinobacteria

Ten samples of tropical lichens collected from Doi Inthanon, Thailand, were explored for the diversity of their bacterial microbiomes through 16S rRNA-based metagenomics analysis. The five predominant lichen-associated bacteria belonged to the phyla Proteobacteria (31.84%), Planctomycetota (17.08%), Actinobacteriota (15.37%), Verrucomicrobiota (12.17%), and Acidobacteriota (7.87%). The diversity analysis metric showed that Heterodermia contained the highest bacterial species richness. Within the lichens, Ramalina conduplicans and Cladonia rappii showed a distinct bacterial community from the other lichen species. The community of lichen-associated actinobacteria was investigated as a potential source of synthesized biologically active compounds. From the total Operational Taxonomic Units (OTUs) found across the ten different lichen samples, 13.21% were identified as actinobacteria, including the rare actinobacterial genera that are not commonly found, such as Pseudonocardia, Kineosporia, Dactylosporangium, Amycolatopsis, Actinoplanes, and Streptosporangium. Evaluation of the pretreatment method (heat, air-drying, phenol, and flooding) and isolation media used for the culture-dependent actinobacterial isolation revealed that the different pretreatments combined with different isolation media were effective in obtaining several species of actinobacteria. However, metagenomics analyses revealed that there were still several strains, including rare actinobacterial species, that were not isolated. This research strongly suggests that lichens appear to be a promising source for obtaining actinobacteria.

Monitoring Heavy Metal Concentrations Using Transplanted Lichen in a Tourism City of Malaysia

Heavy metals are major pollutants in tourist cities due to transportation and urbanization. This study aimed to assess heavy metal concentrations using transplanted lichen in tourist cities. The project was conducted in Malacca, Malaysia, using transplanted Usnea misaminensis lichen at ten sampling stations. After one month, these lichen samples were collected and heavy metal analysis was carried out in a lab using ICP-MS. Other factors, such as the number of vehicles, temperature, relative humidity, and wind speed, were also recorded. The results indicated that the heavy metal concentrations in Malacca were higher than at the control station. The ranking of heavy metal concentrations in the study areas was Fe > Zn > Mn > Pb > Cr > Cu. Furthermore, a positive correlation was also found between the number of vehicles and temperature with the heavy metal concentrations determined within the study areas, while relative humidity and wind speed showed a negative correlation with the heavy metal concentrations detected. The usage of lichens to observe and monitor the chemical compositions in the atmosphere is considered to be relevant these days because they allow for long-term data from the ecosystem to be obtained due to their long life span. This research also emphasizes the need for a better plan for Malacca. Local authorities need to re-plan and redesign Malacca to ensure that pollutants can be flushed out, the city looks greener and cooler, and more non-motor vehicles are used as public transport.

Aliphatic hydrocarbons in the lichen class Lecanoromycetes and their potential use as chemotaxonomic indicators and biomarkers

Lichens are found in a wide range of terrestrial habitats and have important roles in terrestrial ecosystems. However, because lichens are easily decomposed and are rarely preserved as fossils, their paleoenvironmental ecology and evolutionary history remain a mystery. We performed lipid analyses on 29 lichen samples belonging to Lecanoromycetes, the largest class of lichens, from several locations in Japan, to determine their potential for use as taxonomic tools and biomarkers. We found that the lichens contained aliphatic hydrocarbons, including n-alkanes, alkenes, and long-chain branched alkanes, fernenes, diploptene, and hop-21-ene. Lichens with a green algal photobiont (photosynthetic symbiotic algae) contained 1,8-heptadecadiene or 6,9-heptadecadiene and 8- and 7-heptadecene, whereas lichens with cyanobacteria as a photobiont did not contain the heptadecadienes but did contain octadecene, nonadecene and nonadecadiene. These differences in characteristics could be attributed to phylogenetic differences in the photobionts that comprised the lichens, indicating that the alkene composition could be used for lichen chemotaxonomy. Although additional research is needed to confirm that this signal gets preserved in sedimentary archives, our results suggest a previously unknown origin for the C17–C19 alkenes in sediments and imply that these components could be used to reconstruct the past composition of lichens.

Culturable Diversity of Lichen-Associated Yeasts through Enrichment Strategies

Lichens are symbiotic partnerships between a filamentous fungus and a photosymbiotic “alga”. Studies show that lichens harbor endothallic fungi, but that some taxa have been difficult to isolate from the main filamentous thallus-forming fungus and other faster growing lichenicolous/endothallic fungi. Therefore, we aimed to develop and evaluate liquid yeast-enrichment strategies to (1) isolate lichen-associated yeasts in pure culture, and (2) determine the taxonomic placement and breadth of the diversity of culturable yeasts. Eighty-two lichen samples were collected and washed with distilled water, and healthy thalli were ground up and added to seven different yeast-enrichment broths. Yeast colonies were isolated in pure culture and identified using molecular techniques. Initial isolates were identified using BLASTn analysis, and a taxonomic refinement was completed using PhyML analysis. In total, 215 isolates were obtained. The most prevalently isolated ascomycetous yeasts were within the Dothideomycetes (Aureobasidium, Plowrightia, and Dothiora), while the most frequently isolated basidiomycetous yeasts belonged to the genera Curvibasidium, Sporobolomyces, and Tremella. The generic placements could not be determined for 17 isolates, and in total 25 novel species were recovered. The results of this research indicate that (1) lichen-associated yeasts are diverse, (2) employing liquid enrichment strategies is effective for isolating many of these, and (3) lichen thalli represent a valuable untapped reservoir of diverse and novel yeast species.

Membrane lipid peroxidation in lichens determined by the TBARS assay as a suitable biomarker for the prediction of elevated level of potentially toxic trace elements in soil

The use of biomarkers defined as measurable biological parameters at the sub-organism level in which structural or functional changes indicate the presence of pollutants is a promising approach to identify affected sites. The aim of the study was to test the suitability of the level of membrane lipid peroxidation in the widespread epigeic lichen Cladonia rei for the assessment of soil pollution and to develop an effective method to recognise elevated concentrations of potentially toxic trace elements in soil. We collected lichen and soil substrate samples from variously polluted sites and determined the level of membrane lipid peroxidation in the thalli using the thiobarbituric acid-reactive substances (TBARS) assay. Based on the concentrations of Zn, Pb, Cd and As in the soil samples, we calculated the Pollution Load Index (PLI) for particular sampling sites to consider the combined effect of several toxic elements. The model of relationships between TBARS concentrations and PLI revealed that membrane lipid peroxidation does not increase linearly with PLI value, which suggests that above a certain threshold, oxidative stress induced activation of defence aimed at counteracting deleterious effects. We observed that if PLI exceeded the value of 100, the concentrations of TBARS were markedly increased and did not drop below 30 nmol g−1 DW. On the other hand, in lichen samples collected at sites with PLI < 10, TBARS concentrations were lower and as a rule did not exceed 25 nmol g−1 DW. Therefore, we concluded that the effect of soil pollution on membrane lipid peroxidation in the thalli of C. rei can be used in passive soil quality biomonitoring, according to the principle that an increased level of membrane lipid peroxidation is predictive for increased concentrations of elements in the host substrate. Given that this species has not been analysed in detail for the use of biomarkers, this study establishes a baseline and supports practicable use of TBARS concentrations in lichens as biomarkers.

БІОГЕОХІМІЧНЕ ЛІХЕНОІНДИКАЦІЙНЕ ВИВЧЕННЯ СТАНУ ТА ДИНАМІКИ АТМОСФЕРНОГО ЗАБРУДНЕННЯ ДЕНДРОПАРКУ "АСКАНІЯ -НОВА"

By the method of biogeochemical lichen indication on the territory of the arboretum of the Falz-Fein Biosphere Reserve "Askania-Nova" (Kherson Region, UKRAINE) the temporal trends (2011-2021) in the concentrations of heavy metals and other micro- and macro-elements in the epiphytic lichens was estimated. The lichens samples of Parmelia sulcata, Xanthoria parietina and Evernia prunastri collected in 2011 (39 sites) and 2021 (44 sites) for the concetrations of 22 chemical elements (Al, B, Ba, Ca, Cd, Cr, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, S, Sb, Se, Sr, Ti, V and Zn) by the ICP-OES spectroscopy were analysed. In order to correctly compare the concetrations of elements in different species of lichens, their intercalibration to the base species P. sulcata was carried out and the calibration coefficients, the so-called biogeochemical lichen indicies (BGCHL indicies), were calculated. Based on these indicies the arithmetically averaged hypothetical concetrations of elements in lichen samples collected at the sites, where P. sulcata was absent, were calculated and corresponding databases of element concentrations for all three species were created. Factor analysis was applied to identify possible sources of the elements determined in the lichens for the period of 2011 (Fa-1 – Fa-8) – 2021 (Fb-1 – Fb-8). The eight resulting factors represent crust and anthropogenic components. Some of the factors were interpreted as being associated with the agricultural activities, microclimate, pH of atmospheric precipitation and with the higher plants factor (leaching of еlements and their absorption by lichens). The factor structure of the chemical elements concetrations in the lichens growing on the studied area was formed under regional conditions of the accumulation of Cr, Na, Ti, as well as a decrease in the concetrations of such elements as V, Zn, Mn, Cu, Mg, K, Sr, Ba, Pb, Ni, Ca, S and Se. Moreover, Sb and Ba have spatially heterogeneous dynamics of their concetrations, and Se has very heterogeneous dynamics with a decreasing trend of the concentrations.

Evaluation of Antibacterial Potencies of Eight Lichen Extracts Against Gram-Positive Moderately Halophilic Bacteria

The leather sector has global economic importance. Overcoming microbiological problems, especially arising from halophilic bacteria, will greatly reduce product losses. In this study, lichen species including Usnea sp., Platismatia glauca, Ramalina farinacea, Evernia divaricata, Bryoria capillaris, Hypogymnia tubulosa, Pseudevernia furfuracea and Lobaria pulmonaria were examined for their antibacterial efficacies against Staphylococcus saprophyticus subsp. saprophyticus (TR5) and Salinicoccus roseus (KV3) which are proteolytic and lipolytic Gram-positive moderately halophilic bacteria. The extracts of P. glauca, B. capillaris, P. furfuracea and L. pulmonaria had no antibacterial efficacy against the test bacteria. On the other hand, the extracts of H. tubulosa, R. farinacea, Usnea sp. and E. divaricata had considerable antibacterial effect with varying percentages of inhibition. The maximum inhibition ratios at the tested concentrations of 15–240 μg ml–1 for lichen samples of H. tubulosa, R. farinacea, Usnea sp. and E. divaricata were detected as 94.72 ± 0.75%, 76.10 ± 1.85%, 99.36 ± 0.04%, 89.49 ± 2.26% for TR5 and 97.44 ± 0.14%, 95.92 ± 0.29%, 97.97 ± 0.39%, 97.58 ± 0.53% for KV3, respectively. The most remarkable suppression was obtained with Usnea sp. extracts against KV3. These results indicate the need for further studies investigating the applicability of these natural resources to control moderately halophilic bacteria in the preservation of raw hides and skins.

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.

Elemental and chemometric analysis of baseline gradient contamination in Usnea barbata lichens from Tierra del Fuego (South Patagonia)

In order to provide an updated baseline assessment of elemental concentrations in native lichens samples collected at eight selected sampling sites from Tierra del Fuego (South Patagonia), we have determined the concentration of more than forty elements in Usnea barbata by means of different analytical techniques (INAA, ICP-MS, ICP-OES, AMA and CV-AFS), and compared the results in order to ensure reliable data at the moment to perform a comprehensive management of pristine environments.New chemometrics approaches have been employed to identify different tracers of anthropic activities, highlighting their possible gradient concentration and providing a environmental management tool. Overall, most of elements’ concentration were comparable with recent literature, with the exception of Br, Hg, Li and Lu.Subsequently, multivariate data analysis has been performed on the data-set to highlight a possible natural grouping of samples. HCA and PCA pointed out the presence of three clusters, while variables selection pointed out nineteen elements as the most influencing of the clustering.A concentration decrease of Sb and Sn from cluster 1(containing a site situated close to Ushuaia and its International Airport) to cluster 3 was found. These elements’ concentration is related to anthropogenic activities, such as combustive processes, vehicular traffic, waste burning and dust resuspension.The results here presented confirmed that TdF is still a slightly contaminated environment. Furthermore, the elements’ concentration reported in this paper could be considered as baseline levels useful for environmental management, in term of prevention and protection.

New records of five Staurothele species (Verrucariacaea, Ascomycota) from Iran

This study aimed to the taxonomic investigation of the genus Staurothele (Ascomycota, Verrucariaceae) in northeast Iran. Lichen samples were collected from the Khorasan Razavi province and their morphological, anatomical, and ecological features were studied. Five species (Staurothele lecideoides, Staurothele frustulenta, Staurothele drummondii, Staurothele rufa, and Staurothele polygonia) were documented for the first time from Iran.

The potential use of elemental content of saxicolous lichens as bioindicators of nitrogen deposition in the central and southern California mountains

High elevation and arid wilderness areas generally lack epiphytic lichen species used for air quality biomonitoring. We assessed the potential of saxicolous lichens to serve as bioindicators of nitrogen (N) and sulfur (S) deposition by examining relationships among deposition, environmental variables, and elemental concentrations in the saxicolous lichens Umbilicaria phaea (n = 51), Rhizoplaca melanophthalma (n = 20), and the epiphytic lichen Letharia vulpina (n = 16) in the southern Sierra Nevada (SN) and San Bernardino Mountains (SBM) of California, USA. Lichen samples were collected between 2013 and 2019 in 31 plots between 180 and 3330 m elevation. These samples were analyzed for concentrations of 23 elements, including N and S. Signal-to-noise ratios were high comparing the variation among plots to within plots and within samples for N and S concentrations of the Umbilicaria phaea samples. While Umbilicaria phaea N and S concentrations were correlated with modeled N and S deposition estimates, Rhizoplaca melanophthalma and Letharia vulpina N and S concentrations were not. Subsequent principal components analysis and cluster analysis of the Umbilicaria phaea dataset revealed differences in elemental profiles between the SN and SBM, with the SBM samples having higher concentrations of most elements, including heavy metals. Additionally, the first two principal components explained most of the variation (61 %) in elemental content and had strong relationships to latitude, longitude, N and S deposition, and precipitation. We conclude that the elemental profile of Umbilicaria could be used to assess N and S deposition for areas in the western USA that lack suitable epiphytic lichen species.

Türkiye'deki Bazı Cladonia Türlerindeki Eser Elementlerin ICP-MS ile Belirlenmesi

Aim of study: Lichens are biological indicators of environmental pollution of both natural and artificial origin in terms of various elements. In 9 samples (Cladonia coniocraea, C. fimbriata, C. firma, C. foliacea, C. furcate, C. pocillum, C. pyxidata, C. rangiformis and C. subulata) belonging to the genus Cladonia collected from different regions of Turkey; Aluminum, Chromium, Manganese, Iron, Cobalt, Nickel, Copper, Zinc, Arsenic, Selenium, Strontium, Cadmium, Tin, Mercury and Lead element amounts were investigated.&#x0D; Area of study: Lichen samples belonging to the same genus were collected in field studies conducted in 7 different cities in Turkey.&#x0D; Material and methods: All samples were analyzed independently after solubilization in acid medium in microwave system and in triplicate. The accuracy of the results has been confirmed by analysis of 1547 Peach Leaf certified reference material.&#x0D; Main results: Sources of metals, metal accumulation mechanisms and how much they are absorbed by lichens were determined. The highest Al, Cr, Ni concentrations in Cladonia firma are 429.3, 3.04, 13.53 µg/g, respectively. The highest Co, Sr, Cu, Se, Hg concentrations in Cladonia subulata are 0.81, 33.59, 13.16, 0.158, 0.060 µg/g, respectively. The highest Pb, Cd, Sn concentrations in Cladonia pyxidata are 5.90, 0.30, 6.50 µg/g, respectively. The highest Fe, Mn, Zn, As concentrations were 228.7, 17.8, 26.44 and 1.335 µg/g, respect.&#x0D; Highlights: The results showed that metal accumulation in lichens was directly related to the environment in which lichens were collected.

Microbiomic Analysis of Bacteria Associated with Rock Tripe Lichens in Continental and Maritime Antarctic Regions.

Increased research attention is being given to bacterial diversity associated with lichens. Rock tripe lichens (Umbilicariaceae) were collected from two distinct Antarctic biological regions, the continental region near the Japanese Antarctic station (Syowa Station) and the maritime Antarctic South Orkney Islands (Signy Island), in order to compare their bacterial floras and potential metabolism. Bulk DNA extracted from the lichen samples was used to amplify the 18S rRNA gene and the V3-V4 region of the 16S rRNA gene, whose amplicons were Sanger- and MiSeq-sequenced, respectively. The fungal and algal partners represented members of the ascomycete genus Umbilicaria and the green algal genus Trebouxia, based on 18S rRNA gene sequences. The V3-V4 sequences were grouped into operational taxonomic units (OTUs), which were assigned to eight bacterial phyla, Acidobacteriota, Actinomyceota, Armatimonadota, Bacteroidota, Cyanobacteria, Deinococcota, Pseudomonadota and the candidate phylum Saccharibacteria (also known as TM7), commonly present in all samples. The OTU floras of the two biological regions were clearly distinct, with regional biomarker genera, such as Mucilaginibacter and Gluconacetobacter, respectively. The OTU-based metabolism analysis predicted higher membrane transport activities in the maritime Antarctic OTUs, probably influenced by the sampling area’s warmer maritime climatic setting.

Accumulation of 137Cs by Thallus of Epiphytic Lichen Hypogymnia physodes (L.) Nyl on Different Trunk Height in Pine Stands

Lichens are considered by researchers as bioindicators of environmental pollution by artificial radionuclides, including 137Cs. One of these bioindicator species is epiphytic lichen Hypogymnia physodes (L.) Nyl, the use of which for radioecological monitoring can be modified by several factors: tree species, placement on the tree (branches – trunk), height of sampling, etc. The purpose of this study was to investigate the specific activity of 137Cs in thalli of hypogymnia in pine stands: on trunks of Pinus sylvestris L. and Betula pendula Roth at different heights of sampling in 3 height ranges: 0–65, 65–130, and 130–195 cm, and to analyse the intensity of radionuclide accumulation in the “lichen thallus – tree bark” link for both tree species in all height ranges. The study was conducted in August 2021 in the Korosten district of the Zhytomyr Oblast, Zhytomyr Polissia, on 4 test plots, in the Drevlianskyi nature reserve, mainly in middle-aged pine stands with an admixture of birch, where 130 samples of soil, tree bark, and lichen were taken. Specific activity of 137Cs in the samples was measured using a SEG-001 “AKP-s”-150 gamma-ray spectrometer with a BDEG-20R2 scintillation detector (NaI(Tl). It was demonstrated that the content of 137Сs in the thalli of Hypogymnia physodes at different altitude ranges did not differ statistically significantly at the 95% confidence level in all test plots on pine. A preliminary conclusion was made on the possibility of sampling Hypogymnia physodes thalli on pine trunks in the height range of 0–195 cm; however, for the convenience of sampling, it is recommended to perform sampling within 130–195 cm. It has been proven that both the specific activity of 137Сs in Hypogymnia physodes thalli and the intensity of 137Сs accumulation in the chain “Hypogymnia physodes - tree bark” are approximately 2 times higher on pine compared to birch. It was found that on a birch, the content of 137Сs in lichen between the height ranges of 0–65 and 65–130 cm, and 0–65 and 130–195 cm differs significantly at the 95% confidence level; therefore, it is recommended to sample Hypogymnia physodes on a birch in the range of 65–130 cm.

First faunistic report of limno-terrestrial tardigrades (Tardigrada Doye&amp;#768;re, 1840) from the Maltese Islands

Until now, the tardigrade fauna of the Maltese archipelago was unknown, since only the presence of unidentified tardigrades in Malta was reported in the literature. The present study includes the analysis of 11 moss and lichen samples collected in 2015 and 2017 from the islands of Malta and Gozo, and 10 historical microscopic preparations from past fieldwork by Pilato and Binda. Eleven species are reported for the Maltese archipelago, of which, three are new to science but still to be formally described. The taxonomic and faunistic data obtained are discussed in comparison with those of Sicily and North Africa, aiming to draft preliminary faunistic and biogeographic considerations.

ASAP-MS and DART-MS as ancillary tools for direct analysis of the lichen metabolome.

Lichens contain unique metabolites that most often need to be characterized from a limited amount of material. While thin layer chromatography is still the preferred analysis method for most lichenologists, liquid chromatography gives a deeper insight in the lichen metabolome, but an extractive step is needed before any analysis. Therefore, ambient ionization mass spectrometry (MS) analysis of lichen samples using Atmospheric Solid Analysis Probe (ASAP) and Direct Acquisition in Real Time (DART) techniques is evaluated. We looked for a faster method to screen the metabolome by disrupting the classical workflow of analysis. Four lichens selected for their metabolic diversity were analyzed with MS; namely Evernia prunastri, Lichina pygmaea, Parmelia saxatilis, and Roccella fuciformis. ASAP and DART analyses were compared against the reference electrospray ionization with a bioinformatic process including Van Krevelen diagrams as well as the multivariate comparison of the ionization methods in positive and negative modes. Metabolite profiles obtained from DART and ASAP analyses of lichen samples are consistent with classical analyses of lichen extracts. Through an easy and rapid experiment and without any extraction solvent, a large and informative profile of lichen metabolites is obtained when using complementary ionization modes of these high resolution mass spectrometry methods. ASAP-MS and DART-MS are two ancillary methods that provide a comprehensive evaluation of the lichen metabolome.

Influence of environmental and dietary exposures on metals accumulation among the residents of a major industrial harbour (Fos-sur-Mer, France)

ObjectivesWe sought to determine whether the residents living closer to the core industrial zone (Fos-sur-Mer) had higher trace metals blood and urinary levels than residents who lived further away (Saint-Martin-de-Crau). Materials and MethodsAs part of The INDEX study, we measured the following trace metals into blood and urine samples of 138 participants (80 in the core industrial zone and 58 in the reference area): Antimony, Arsenic, Cadmium, Chromium, Cobalt, Mercury, Nickel, Lead and Vanadium. Participants were recruited using a stratified random sampling method and had to meet the following inclusion criteria: 30–65 years old, living in the area since at least 3 years, not working in the industrial sector, non-smoker. We used single-pollutant multivariate linear regression models, using substitution when censored data were under 15 % and Tobit models alternatively, adjusting for personal physiological, social, dietary, housing characteristics and leisure activities. We also measured these trace metals in samples of lichens (Xanthoria parietina) and atmospheric particles (PM2.5). ResultsWe showed higher lichen and air levels of several metals (Cd, Cr, Co, Ni and Pb) in the exposed area. Living close to the core industrial zone was significantly associated with an increase in blood levels of lead (adjusted geometric mean = 17.2 [15.8–18.7] vs 15.1 [13.7–16.7] µg.L−1, p < 0.05). We report significant increase of some metals urinary levels among residents of the industrial port zone, as the result of the use of the environment, itself contaminated by industrial activities: dietary history of self-consumption of vegetables (Cadmium), eggs and poultries (Vanadium). However, Vanadium levels were greater among self-consumers of poultry in the reference area and gardeners had circulatory levels of Lead greater than non-gardeners only in the reference area. Consumption of non-local sea-products increased the level of Cadmium. ConclusionsThese results brought interesting clues, in complement to national programs, regarding the exposure to trace metals of residents living in a major industrial harbor.

Biomonitoring Potentially Toxic Elements (PTEs) Using Lichen Transplant Usnea misaminensis: A Case Study from Malaysia

Urban air pollution has been a major concern due to its impact on global public health. Various techniques for monitoring urban air quality have been developed. However, there is currently a dearth of research on how effective bioaccumulators such as lichen are at monitoring urban air pollution. As a result, the purpose of this research is to investigate the use of U. misaminensis as a biological indicator for biomonitoring urban air quality in Malaysia. Three months were spent exposing lichen samples in three Malaysian cities (Kuala Lumpur, Penang, and Johor Bahru). The trace element content and vitality of the lichens were assessed. The results of this study revealed that U. misaminensis is an effective biological indicator for measuring 25 elements of air pollutants in metropolitan areas. They also revealed that all 25 elements accumulated in the urban area sample were greater than in the control sample. The vitality rate of lichens dropped in the urban area sample when compared with the control sample, indicating that an increase in elements in the air will impact the vitality rate of any biological component. In this study, two arguments are made: (a) Lichen is an excellent biological indicator, particularly for urban air pollutants such as potentially toxic elements; and (b) traffic is the primary contributor to urban air pollution; hence, the local government requires a better plan and design for urban areas to decrease air pollutants build-up.

Phytochemical Characterization and Pharmacological Properties of Lichen Extracts from Cetrarioid Clade by Multivariate Analysis and Molecular Docking.

Introduction Lichens, due to the presence of own secondary metabolites such as depsidones and depsides, became a promising source of health-promoting organisms with pharmacological activities. However, lichens and their active compounds have been much less studied. Therefore, the present study aims to evaluate for the first time the antioxidant capacity and enzyme inhibitory activities of 14 lichen extracts belonging to cetrarioid clade in order to identify new natural products with potential pharmacological activity. Materials and Methods In this study, an integrated strategy was applied combining multivariate statistical analysis (principal component analysis and hierarchical cluster analysis), phytochemical identification, activity evaluation (in vitro battery of antioxidant assays FRAP, DPPH, and ORAC), and enzyme inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) and molecular profiling with in silico docking studies of the most promising secondary metabolites. Results. Among fourteen lichen samples, Dactylina arctica stands out for its higher antioxidant capacities, followed by Nephromopsis stracheyi, Tuckermannopsis americana, Vulpicida pinastri, and Asahinea scholanderi. Moreover, Asahinea scholanderi and Cetraria cucullata extracts were the best inhibitors of AChE and BuChE. The major secondary metabolites identified by HPLC were alectoronic acid and α-collatolic acid for Asahinea scholanderi and usnic acid and protolichesterinic acid for Cetraria cucullata. Molecular docking studies revealed that alectoronic acid exhibited the strongest binding affinity with both AChE and BuChE with and without water molecules. Conclusions Our results concluded that these species could be effective in the treatment of neurodegenerative diseases, being mandatory further investigation in cell culture and in vivo models.