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1.
Environ Monit Assess ; 192(4): 222, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32146527

RESUMO

The determination of trace metal contents directly from a solid sample is a trend in modern atomic spectrometry. The aim of this study was to develop an analytical method for the routine determination of Cd in lichens using solid sampling graphite furnace atomic absorption spectrometry (SS-GF-AAS). For the determination of Cd, the temperature program of the graphite furnace was optimized using a mixed matrix modifier (Pd + Mg (NO3)2 + Triton X-100). The limit of detection and the limit of quantification were 0.9 µg/kg and 3 µg/kg, respectively. The analytical method for Cd determination in the plant matrix was verified by the analysis of certified reference materials of lichens, seaweed, and rye grass. The developed procedure was applied to the study of Cd distribution in thalli of Usnea antarctica lichen from James Ross Island, Antarctica. The SS-GF-AAS analytical method is particularly suited for use in environmental studies and plant physiology (the microanalysis of anatomical structures).


Assuntos
Cádmio , Poluentes Ambientais , Grafite , Líquens , Regiões Antárticas , Cádmio/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Ilhas , Líquens/química , Espectrofotometria Atômica
2.
Chemosphere ; 241: 125064, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31683434

RESUMO

The use of naturally occurring epiphytic lichens can be an effective tool for regional monitoring of mercury (Hg) and other potentially toxic elements (PTEs). Nova Scotia, Canada is a hotspot for mercury and other trace metal accumulation in ecosystems; partially attributed to long-range transport of air pollution. The relative contribution of local and international sources of Hg to local air in Nova Scotia is unknown. This study assessed the potential of epiphytic lichens (Usnea spp.) as passive samplers for PTE air pollution in Nova Scotia. Lichens (n = 190) collected across mainland Nova Scotia were analyzed for PTEs. Results indicate that there are 3 distinct clusters of PTEs which suggest patterns and sources for each elemental cluster. Hg was correlated with longitude and prevailing wind direction, and Hg was not significantly different in site-specific hotspot sampling nor year of sampling. Our data support the hypothesis that Hg in lichens is from historical and ongoing long-range transport and diffuse emission patterns rather than localized pollution sources. PTE concentrations were shown to have median values that are similar to other remote regions (such as the Antarctic) however the maximum values were observed to be substantially higher for some elements (e.g. lead, cadmium). This research supports the use of lichens as biomonitors and provides a baseline for future monitoring efforts to identify changes in PTE distribution in Nova Scotia with ongoing industrial activity and a changing climate.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Líquens/química , Mercúrio/análise , Oligoelementos/análise , Poluição do Ar/estatística & dados numéricos , Regiões Antárticas , Cádmio , Ecossistema , Nova Escócia , Oligoelementos/toxicidade , Vento
3.
Chem Biodivers ; 17(1): e1900465, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31701649

RESUMO

We performed comparative profiling of four specialized metabolites in the lichen Evernia prunastri, collected at three different geographic locations, California and Maine, USA, and Yoshkar Ola, Mari El, Russia. Among the compounds produced at high concentrations that were identified in all three specimens, evernic acid, usnic acid, lecanoric acid and chloroatranorin, evernic acid was the most abundant. Two depsidones, salazinic acid and physodic acid, were detected in the Yoshkar-Ola collection only. The crystalline structure of evernic acid (2-hydroxy-4-[(2-hydroxy-4-methoxy-6-methylbenzoyl)oxy]-6-methylbenzoate) (hmb) revealed two crystallographically and conformationally distinct hmb anions, along with two monovalent sodium atoms. One hmb moiety contained an exotetradentate binding mode to sodium, whereas the other exhibited an exohexadentate binding mode to sodium. Embedded edge-sharing {Na2 O8 }n sodium-oxygen chains connected the hmb anions into the full three-dimensional crystal structure of the title compound. The crystal used for single-crystal X-ray diffraction exhibited non-merohedral twinning. The data suggest the importance of the acetyl-polymalonyl pathway products to processes of maintaining integrity of the lichen holobiont community.


Assuntos
Benzofuranos/análise , Hidroxibenzoatos/análise , Líquens/química , Salicilatos/análise , Benzofuranos/metabolismo , Hidroxibenzoatos/metabolismo , Líquens/metabolismo , Modelos Moleculares , Salicilatos/metabolismo
4.
Recent Pat Biotechnol ; 14(1): 16-32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31438835

RESUMO

BACKGROUND: Recently, it has been established that simultaneous saccharification and fermentation is a potent technique for the detoxification of harmful plant materials. OBJECTIVE: Following encouraging simultaneous medicinal applications of snail slime and yeast, we exploited their hydrolytic and fermentation potentials to prevent toxicities of the selected floras; Erythrodontium barteri (EB), bracken fern (BF), and crustose lichens (CL). The applicability of the saccharification process has been described in a patent (WO2005010193A2). METHODS: The plants were bioprocessed using snail digestive juice and yeast slurry and their health effects were evaluated. Seventy rats were divided equally into groups, treated with single doses of aqueous extracts of the plants and their bioprocessed forms, and compared with control rats. RESULTS: The plants showed very high antinutrients levels, which significantly reduced after SSF with enhanced flavonoids, alkaloids and phenols. Potential alterations of WBC differentials, RBC, liver and renal function markers indices were mitigated by bioprocessed extracts. MDA, SOD, GRase, XO and XDH levels in rats administered the bEB and CL were equivalent to the levels found for the control rats. Some bioprocessed plants produced unaltered insulin, ghrelin, and leptin levels. The bioprocessed extracts, when compared to the effects of unprocessed extracts, produced lower TNF-α, Caspase-3, and adiponectin levels and mitigated the potential suppression of Na+/K+-ATPase levels. Potential depletion of inhibin-B, testosterone, estrogen, and prolactin was mitigated after bioprocessing. CONCLUSION: This study, thus, validates the application of bioprocessing using snail digestive juice and yeast as an effective approach to reduce the potential toxicities of harmful plants.


Assuntos
Produtos Biológicos , Fígado , Extratos Vegetais , Animais , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Biotransformação , Glicemia/efeitos dos fármacos , Embriófitas/química , Feminino , Testes Hematológicos , Líquens/química , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Patentes como Assunto , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacocinética , Extratos Vegetais/toxicidade , Ratos , Ratos Wistar , Caramujos/química , Leveduras/química
5.
Environ Pollut ; 256: 113468, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31679880

RESUMO

The increasing content of platinum group metal particles emitted into the environment by car traffic is gradually attracting the attention of the scientific community. However, the methods for the determination of platinum group metals in environmental matrices are either costly or suffer from low sensitivity. To facilitate the use of less sensitive, but significantly cheaper, devices, the preconcentration of platinum group metals is employed. For platinum, a multitude of preconcentration approaches have been published. On the contrary, the preconcentration approaches for palladium are still rare. In this work, the development, optimization, and testing of a new approach is described; it is based on a preconcentration of palladium on octadecyl modified silica gel together with the complexing agent dimethylglyoxime, and it is then analyzed with the high-resolution continuum-source atomic absorption spectrometry. For comparison, a newly developed sorbent, QuadraSil™ TA, with a high affinity for platinum group metals was also tested. The preconcentraiton approach was tested on the lichen Hypogymnia physodes, which served as a bioindicator of palladium emissions. The case study site was a mid-sized city in central Europe: Brno, Czech Republic. The dry "bag" monitoring technique was used to collect the palladium near roads with a large span of traffic density. The developed analytical approach confirmed an increasing concentration of palladium with increasing exposure time and intensity of the traffic. Consequently, a simple relationship between the amount of bioaccumulated palladium and traffic density was established.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Líquens/química , Paládio/análise , Cidades , República Tcheca , Paládio/química , Platina/análise , Sílica Gel , Espectrofotometria Atômica/métodos
6.
Chemosphere ; 239: 124783, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726517

RESUMO

This research concerned radioactivity of lichens and mosses from coastal zones of the Canadian Arctic and Alaska. Over 50 samples were collected from 7 positions during two scientific expeditions in 2012 and 2013. The tundra contamination caused by anthropogenic radionuclides was relatively low, reaching mean values with SD's of: 17.4 ±â€¯3.5 Bq/kg for 90Sr, 14.0 ±â€¯2.9 Bq/kg for 134Cs, 38.4 ±â€¯7.5 Bq/kg for 137Cs, 0.86 ±â€¯0.24 Bq/kg for 239+240Pu, 0.065 ±â€¯0.017 Bq/kg for 238Pu and 0.50 ±â€¯0.13 Bq/kg for 241Am. The increase of activity concentration with increasing latitudes was noticed mostly in regard to 90Sr, Pu isotopes and 241Am. The analysis of isotopic ratios exhibited dominant contribution of the global fallout (+SNAP 9A satellite re-entry fallout) for the presence of plutonium isotopes and 241Am. The Fukushima fallout signature was identified in a few lichens from Alaska. However, the influence of additional unknown factor on the occurrence of 90Sr and 137Cs has been detected in western part of Canadian Arctic. Natural radioisotopes of thorium and uranium were found throughout the entire investigated region and the average values of activity concentration with SD's were as follows: 2.92 ±â€¯0.47 Bq/kg for 230Th, 2.61 ±â€¯0.48 Bq/kg for 232Th, 4.32 ±â€¯0.80 Bq/kg for 234U and 3.97 ±â€¯0.71 Bq/kg for 238U. Examined Western Arctic tundra was not affected with any technically enhanced natural radioactivity.


Assuntos
Poluentes Radioativos do Ar/análise , Briófitas/química , Líquens/química , Cinza Radioativa/análise , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Alaska , Regiões Árticas , Canadá , Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Plutônio/análise , Monitoramento de Radiação/métodos , Tório/análise , Urânio/análise
7.
Environ Monit Assess ; 192(1): 37, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31828442

RESUMO

This study presents a comparative assessment of the trace metal air pollutants of urban, peri-urban, and rural areas of the Brahmaputra Valley plain in the Eastern Himalayan region using biomonitoring of Pyxine cocoes. In situ collection of the thalli growing on Bombax sp. from representative locations was done, which was analyzed for Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn using ICP-OES. The metals, viz. Cd, Cr, Ni, Pb, and Zn, were highly enriched, indicating anthropogenic influences. The coefficients of variation (CV) of Co, Cr, and Ni were also high, pointing at their accumulation from local sources. Influence of local sources was also observed for Cd, Fe, and Mn in peri-urban and Cd in urban samples. Metals related to automobiles were accumulated in greater volume in samples of peri-urban locations, which implies the impact of the highway that runs through these locations and other associated human activities. The samples of urban areas were found to be enriched with metals originating from both vehicular emissions and road dust. Also, accumulations of Co, Cr, Cu, Fe, Mn, and Ni in the lichen thalli were found to be around tea gardens. Inter-species correlations were found to be positively significant for most of the elements. Principal component analysis (PCA) of the metal data revealed that vehicular emission and coal burning, street dust, and crustal dust were the major sources of trace metals in the ambient air of the region.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Líquens/química , Metais/análise , Ascomicetos , Automóveis , Carvão Mineral/análise , Poeira/análise , Humanos , Metais Pesados/análise , Oligoelementos/análise , Emissões de Veículos/análise
8.
Environ Monit Assess ; 191(11): 691, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667628

RESUMO

This study identified specific emission sources of atmospheric pollution in the vicinity of two secondary iron and steel smelting factories in Osun state, southwestern Nigeria, using transplanted biomonitors. A total of 120 biomonitors consisting of lichen and moss were grown under a controlled environment and later transplanted to the surroundings of each factory for monitoring of air pollutants for 3 months in both wet and dry seasons. The elemental contents (K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb and Sr) of the biomonitors were determined by X-ray florescence (XRF) spectroscopy. The source identification was performed by applying positive matrix factorization (PMF) receptor modelling approach using the elemental data set from the two smelters. Among the measured elements, Fe had the highest average concentration in the lichen and moss samples as well as in both seasons. The average concentrations of Co, Ni, Cu, Zn, As and Br were low. The varying average elemental concentrations of lichen and moss reflect the pattern of impact of smelting on atmospheric airborne pollution around the factories. The four factors resolved by PMF and their respective contributions were metal processing (39.0%), Fe source (28.0%), crustal/soil (22.0%) and road dust (11.0%) for moss and Fe source (34.0%), crustal/soil (26.0%), coal combustion (25.0%) and road dust (15.0%) for lichen. The study showcases lichen and moss as cheaper and yet efficient uninterrupted monitoring tools of air pollution sources associated with iron and steel smelting industrial activities.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Metalurgia , Aço , Poluição do Ar/análise , Briófitas/química , Carvão Mineral/análise , Poeira , Poluição Ambiental/estatística & dados numéricos , Ferro/análise , Líquens/química , Nigéria , Estações do Ano , Solo/química
9.
Environ Sci Pollut Res Int ; 26(36): 36754-36763, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31741276

RESUMO

Stereocaulon sorediiferum is expected to be a Cu-hyperaccumulator lichen and has fluorescent substances. To clarify the relationship between the fluorescence (FL) of the lichen and its Cu concentration, we collected S. sorediiferum samples at Cu-contaminated and uncontaminated sites in Japan, determined the concentration of Cu, K, Mg, Al, Ca, Mn, Fe, Zn, chlorophyll a,b, and total carotenoids in them, analyzed lichen secondary metabolites and fluorescent substances extracted from them, and measured the FL of them and their extracts. We found that the FL intensity of S. sorediiferum samples is significantly negatively correlated with their Cu concentration. The application of its FL for Cu monitoring may allow a new nondestructive quantitative method for assessing Cu contamination. The spectroscopic and chromatographic analysis shows that the fluorescent substances negatively correlated with Cu concentration are not major lichen secondary metabolites (lobaric acid and atranorin) and remain after immersion in acetone. The correlation analysis and the comparison with the causal relationship between Cu concentration and the chlorophyll a/b ratio suggest that the reason for the decrease in FL intensity with increasing Cu concentration is a structural change of the fluorescent substances by accumulated Cu. These findings lead to a better understanding of the relationship between the FL of S. sorediiferum and its Cu concentration and provide new insights into fluorescent lichen substances.


Assuntos
Poluentes Atmosféricos/toxicidade , Ascomicetos/efeitos dos fármacos , Cobre/toxicidade , Fluorescência , Poluentes Atmosféricos/metabolismo , Ascomicetos/metabolismo , Clorofila , Clorofila A , Cobre/análise , Cobre/metabolismo , Depsídeos , Hidroxibenzoatos , Japão , Lactonas , Líquens/química , Líquens/efeitos dos fármacos , Salicilatos
10.
Biol Res ; 52(1): 55, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601259

RESUMO

BACKGROUND: Epanorin (EP) is a secondary metabolite of the Acarospora lichenic species. EP has been found in lichenic extracts with antimicrobial activity, and UV-absorption properties have been described for closely related molecules; however, its antiproliferative activity in cancer cells has not yet been explored. It has been hypothesized that EP inhibits cancer cell growth. MCF-7 breast cancer cells, normal fibroblasts, and the non-transformed HEK-293 cell line were exposed to increasing concentrations of EP, and proliferation was assessed by the sulforhodamine-B assay. RESULTS: MCF-7 cells exposed to EP were examined for cell cycle progression using flow cytometry, and DNA fragmentation was examined using the TUNEL assay. In addition, EP's mutagenic activity was assessed using the Salmonella typhimurium reverse mutation assay. The data showed that EP inhibits proliferation of MCF-7 cells, and it induces cell cycle arrest in G0/G1 through a DNA fragmentation-independent mechanism. Furthermore, EP's lack of overt cytotoxicity in the normal cell line HEK-293 and human fibroblasts in cell culture is supported by the absence of mutagenic activity of EP. CONCLUSION: EP emerges as a suitable molecule for further studies as a potential antineoplastic agent.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Líquens/química , Antineoplásicos/isolamento & purificação , Fragmentação do DNA , Feminino , Citometria de Fluxo , Humanos , Células MCF-7
11.
Sci Total Environ ; 692: 1005-1021, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539933

RESUMO

Temporal and spatial atmospheric deposition trends of elements to the boreal forest surrounding bitumen production operations in the Athabasca Oil Sands Region (AOSR), Alberta, Canada were investigated as part of a long-term lichen bioindicator study. The study focused on eight elements (sulfur, nitrogen, aluminum, calcium, iron, nickel, strontium, vanadium) that were previously identified as tracers for the major oil sand production sources. Samples of the in situ epiphytic lichen Hypogymnia physodes were collected in 2002, 2004, 2008, 2011, 2014, and 2017 within a ~150 km radius from the center of surface oil sand production operations in the AOSR. Site-specific time series analysis conducted at eight jack pine upland sites that were repeatedly sampled generally showed significant trends of increasing lichen concentrations for fugitive dust linked elements, particularly at near-field (<25 km from a major oil sands production operation) sample locations. Multiple regional scale geostatistical models were developed and evaluated to characterize broad-scale changes in atmospheric deposition based on changes in H. physodes elemental concentrations between 2008 and 2014. Empirical Bayesian kriging and cokriging lichen element concentrations with oil sands mining, bitumen upgrading, coke materials handling, and limestone quarry/crushing influence variables produced spatial interpolation estimates with the lowest validation errors. Gridded zonal mean lichen element concentrations were calculated for the two comprehensive sampling years (2008, 2014) and evaluated for spatial and temporal change. Lichen sulfur concentrations significantly increased in every grid cell within the domain with the largest increases (44-88%) in the central valley in close proximity to the major surface oil sand production operations, while a minor nitrogen concentration decrease (-20%) in a single grid cell was observed. The areal extent of fugitive dust element deposition generally increased with significantly higher deposition to lichens restricted to the outer grids of the enhanced deposition field, reflecting new and expanding surface mining activity.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Líquens/química , Alberta , Atmosfera , Poeira/análise , Campos de Petróleo e Gás
12.
Environ Pollut ; 255(Pt 1): 113239, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31542666

RESUMO

Forty soil and lichen samples and sixteen soil horizon samples were collected in the mining and surrounding areas of the Yamal-Nenets autonomous region (Russian Arctic). The positive matrix factorization (PMF) model was used for the source identification of PAHs. The results of the source identification showed that the mining activity was the major source of PAHs in the area, and that the mining influenced the surrounding natural area. The 5+6-ring PAHs were most abundant in the mining area. The lichen/soil (L/S) results showed that 2+3-ring and 4-ring PAHs could be transported by air and accumulated more in lichens than in the soil, while 5+6-ring PAHs accumulated more in the soil. Strong relationships between the quotient of soil/lichen (QSL) and Log KOA and Log PL and between the quotient of lichen/histic horizon soil and KOW were observed. In addition, hydrogeological conditions influenced the downward transport of PAHs. Particularly surprising is the discovery of the high levels of 5 + 6 rings in the permafrost table (the bottom of the active layer). One hypothesis is given that the global climate change may lead to further depth of active layer so that PAHs may migrate to the deeper permafrost. In the impact area of mining activities, the soil inventory for 5+6-ring PAHs was estimated at 0.14 ± 0.017 tons on average.


Assuntos
Monitoramento Ambiental , Líquens/química , Pergelissolo , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solo/química , Regiões Árticas , China , Minerais , Federação Russa
13.
Sci Total Environ ; 690: 1355-1368, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31470497

RESUMO

Native and transplanted lichens were analyzed as bioaccumulators of airborne particulate matter (PM) in an eastern district of Rome, Italy, where frequent fraudulent fires are set to recover metals, mostly copper, from waste electrical and electronic equipment (WEEE). The presence of native lichens was scarce, due to the drought of spring-summer 2017, thus, sampling was extended to a neighboring area for toughening the dataset to a similar context. The magnetic analyses revealed intense properties connected to the anthropic complexity of the zone, where industrial, traffic and arson-related dusts are emitted and bio-accumulated. Magnetic and chemical analyses were compared, leading to significant linear correlations between the concentration dependent magnetic parameters (susceptibility, saturation magnetization and saturation remanence) and the concentration of heavy metals, among which copper, chrome, lead and zinc. Moreover, selected magnetic particles were chemically and morphologically characterized by Scanning Electron Microscope and Energy Dispersion System microanalyses. Magnetic particles resulted incorporated into the lichens' tissues and their composition, morphology and grain size strongly supported their anthropogenic, mostly combustion-related, origin. Even if, given the complexity of the area, it was not feasible to fully discriminate the multiple anthropogenic sources, magnetic biomonitoring of lichens, especially when combined with microtextural and compositional analyses, confirmed to be an excellent methodology for a rapid characterization of environmental pollution.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Líquens/química , Material Particulado/análise , Itália , Magnetismo , Roma
14.
BMC Res Notes ; 12(1): 550, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31470895

RESUMO

OBJECTIVE: The purpose of this study was to develop and validate a specific and sensitive liquid chromatography tandem mass-spectrometry method for quantification of usnic acid concentration in the lichen, Cladonia uncialis, suitable for detection of relatively small fluctuations of usnic acid concentration in response to environmental changes. RESULTS: The resulting method was fully validated according to international guidelines and demonstrated good selectivity and sensitivity with minor levels of a matrix effect and high accuracy.


Assuntos
Benzofuranos/análise , Cromatografia Líquida/métodos , Líquens/química , Espectrometria de Massas em Tandem/métodos , Bioensaio , Padrões de Referência
15.
Environ Pollut ; 254(Pt A): 113013, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31415978

RESUMO

The study was aimed to evaluate the ability of native lichen Xanthoria (X.) parietina to biomonitor and bioaccumulate some heavy metals (As, Cd, Co, Cr, Ni, Pb), PAHs, PCDDs, PCDFs, PCBs and PBDEs and to evaluate the use of the native X. parietina as a multi-tracer tool for scenarios characterized by different anthropogenic pressures. Samples of native X. parietina were collected in six different sites (two green, two residential and two industrial areas, respectively) and analyzed for the target compounds. The results show that X. parietina was a useful tool for the biomonitoring of air quality in the selected areas, and was able to bioaccumulate all the studied metals and POPs. In particular, the total concentrations dry weight (dw) ranged between 8.1 and 103.4 mg kg-1 for metals, from 113 × 103 to 183 × 103 ng kg-1 for PAHs, from 868 to 7685 ng kg-1 for PCBs, from 14.3 to 113.8 ng kg-1 for PCDDs/Fs (∑TEq = 0.9-7.1), and from 194 to 554 ng kg-1 for PBDEs. Besides, in general, the levels of analytes recovered in the different samples of lichen show an increasing trend from green to industrial sites, especially for PCBs (mean values equal to 1218, 4253 and 7192 ng kg-1 respectively for green, residential and industrial areas). The statistical approach, based on Pearson's correlation and principal component analysis tests, showed that one of the industrial sites was well-separated from the others, that resulted grouped due to some similarities.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Líquens/química , Poluição do Ar/análise , Ascomicetos , Poluentes Ambientais/análise , Indústrias , Metais Pesados/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
16.
Molecules ; 24(16)2019 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-31405197

RESUMO

Psoromic acid (PA), a bioactive lichen-derived compound, was investigated for its inhibitory properties against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), along with the inhibitory effect on HSV-1 DNA polymerase, which is a key enzyme that plays an essential role in HSV-1 replication cycle. PA was found to notably inhibit HSV-1 replication (50% inhibitory concentration (IC50): 1.9 µM; selectivity index (SI): 163.2) compared with the standard drug acyclovir (ACV) (IC50: 2.6 µM; SI: 119.2). The combination of PA with ACV has led to potent inhibitory activity against HSV-1 replication (IC50: 1.1 µM; SI: 281.8) compared with that of ACV. Moreover, PA displayed equivalent inhibitory action against HSV-2 replication (50% effective concentration (EC50): 2.7 µM; SI: 114.8) compared with that of ACV (EC50: 2.8 µM; SI: 110.7). The inhibition potency of PA in combination with ACV against HSV-2 replication was also detected (EC50: 1.8 µM; SI: 172.2). Further, PA was observed to effectively inhibit HSV-1 DNA polymerase (as a non-nucleoside inhibitor) with respect to dTTP incorporation in a competitive inhibition mode (half maximal inhibitory concentration (IC50): 0.7 µM; inhibition constant (Ki): 0.3 µM) compared with reference drugs aphidicolin (IC50: 0.8 µM; Ki: 0.4 µM) and ACV triphosphate (ACV-TP) (IC50: 0.9 µM; Ki: 0.5 µM). It is noteworthy that the mechanism by which PA-induced anti-HSV-1 activity was related to its inhibitory action against HSV-1 DNA polymerase. Furthermore, the outcomes of in vitro experiments were authenticated using molecular docking analyses, as the molecular interactions of PA with the active sites of HSV-1 DNA polymerase and HSV-2 protease (an essential enzyme required for HSV-2 replication) were revealed. Since this is a first report on the above-mentioned properties, we can conclude that PA might be a future drug for the treatment of HSV infections as well as a promising lead molecule for further anti-HSV drug design.


Assuntos
Antivirais , Benzoxepinas , Ácidos Carboxílicos , DNA Polimerase Dirigida por DNA , Herpesvirus Humano 1/fisiologia , Herpesvirus Humano 2/fisiologia , Líquens/química , Simulação de Acoplamento Molecular , Proteínas Virais , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/química , Antivirais/farmacologia , Benzoxepinas/química , Benzoxepinas/farmacologia , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacologia , DNA Polimerase Dirigida por DNA/química , DNA Polimerase Dirigida por DNA/metabolismo , Humanos , Inibidores da Síntese de Ácido Nucleico/química , Inibidores da Síntese de Ácido Nucleico/farmacologia , Células Vero , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/química , Proteínas Virais/metabolismo
17.
Environ Sci Pollut Res Int ; 26(29): 29896-29907, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407267

RESUMO

To assess the two most toxicologically relevant species of As, namely arsenite (As(III)) and arsenate (As(V)), chromatographic separations often require two separate chromatographic columns to address the co-elution of arsenobetaine (AsB) with As(III). This issue is typically observed using conventional isocratic methods on anion exchange columns, increasing cost and analysis time. Here, we optimize the extraction of inorganic As from a lichen air biomonitor and develop an isocratic method for the chromatographic separation of five common As species on a PRP X-100 anion exchange column, resulting in the complete baseline separation of all species under study. This method was then applied to lichen biomonitors from an urban and rural site to demonstrate its use. In order of abundance, the various arsenic species in lichens from the urban site in South Africa were As(V) > As(III) > AsB > dimethylarsinic acid (DMA) > monomethylarsonic acid (MMA), and As(V) > AsB > As(III) > DMA > MMA for the rural site, where MMA was present in extremely low, non-quantifiable concentrations in lichens from both sites. Total concentrations of As were higher in samples from the urban site (6.43 ± 0.25 µg/g) than in those from the rural site (1.87 ± 0.05 µg/g), with an overall extraction efficiency of 19% and 40%, respectively. The optimized method utilized relatively inexpensive solvents and is therefore low-cost and eco-friendly in comparison with conventional chromatographic techniques. This is the first study which addresses the optimized extraction and characterization of As species in a South African lichen biomonitor of air pollution. Graphical abstract .


Assuntos
Arseniatos/análise , Arsenicais/análise , Arsenitos/análise , Líquens/química , /instrumentação , Ácido Cacodílico/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , África do Sul , Urbanização
18.
BMC Complement Altern Med ; 19(1): 221, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31426865

RESUMO

BACKGROUND: Lichens produce a huge diversity of bioactive compounds with several biological effects. Gyrophoric acid (GA) is found in high concentrations in the common lichen Umbilicaria hirsuta, however evidence for biological activity was limited to anti-proliferative activity described on several cancer cell lines. METHODS: We developed and validated a new protocol for GA isolation, resulting in a high yield of highly pure GA (validated by HPLC and NMR) in an easy and time saving manner. Anti-proliferative and pro-apoptotic activity, oxygen radicals formation and stress/survival proteins activity changes was study by flow cytometry. RESULTS: The highly purified GA showed anti-proliferative activity against HeLa (human cervix carcinoma) and other tumor cells. Moreover, GA threated cells showed a significant increase in caspase-3 activation followed by PARP cleavage, PS externalization and cell cycle changes mediated by oxidative stress. Production of oxygen radicals led to DNA damage and changes in stress/survival pathways activation. CONCLUSIONS: GA treatment on HeLa cells clearly indicates ROS production and apoptosis as form of occurred cell death. Moreover, DNA damage and changing activity of stress/survival proteins as p38MAPK, Erk1/2 and Akt mediated by GA treatment confirm pro-apoptotic potential. The pharmacological potential of U. hirsuta derived GA is discussed.


Assuntos
Apoptose/efeitos dos fármacos , Benzoatos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Líquens/química , Estresse Oxidativo/efeitos dos fármacos , Ascomicetos/química , Células HeLa , Humanos , Transdução de Sinais/efeitos dos fármacos
19.
Environ Pollut ; 253: 918-929, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31351300

RESUMO

Huelva is a highly industrialized city in SW Spain hosting, among others, a Cu smelter, a phosphate fertilizer plant, a power plant, and oil refineries. This study aims to evaluate metal concentrations in lichens as bioindicators of atmospheric pollution in the impacted urban areas. Xanthoria parietina species from Huelva and nearby villages, as well as reference samples from remote, non-contaminated urban areas, were analyzed for trace elements (V, Cr, Mn, Co, Ni, Cu, Zn, Sr, As, Cd, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Er, Tm, Yb, Lu, Pb, Th, U) using Inductively Coupled Plasma-Mass Spectrometry; and for major elements (Ca, K, Mg, P, and S) by Inductively Coupled Plasma-Optical Emission Spectrometry after acid digestion. The metal composition of X. parietina exhibits spatial distribution patterns with extremely elevated concentrations (Co, Ni, Cu, Zn, As, Cd, Sb, Ba, Pb, U, and S) in the surroundings of the industrial estates to <1 km distance. Mean concentrations were significantly lower in the urban areas >1 km from the pollution sources. However, air pollution persists in the urban areas up to 4 km away, as the mean concentrations of Cu, Zn, As, Cd, Sb and S remained considerably elevated in comparison to the reference samples. Though rigorous source apportionment analysis was not the aim of this study, a good positive correlation of our results with metal abundances in ambient particulate matter and in pollution sources points to the Cu smelter as the main source of pollution. Hence, the severe air pollution affecting Huelva and nearby urban areas may be considered a serious health risk to local residents.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Metais/análise , Material Particulado/análise , Poluição do Ar/análise , Cidades , Desenvolvimento Industrial , Indústrias , Líquens/química , Espanha , Oligoelementos/análise
20.
Environ Sci Pollut Res Int ; 26(26): 27002-27013, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31313231

RESUMO

Biological materials play a significant role in the treatment of heavy metal-contaminated soil and wastewater. In this study, the Pb2+ biosorption potential of lichen Evernia prunastri, extensively available at a forest in Bilecik-Turkey, was investigated at batch-scale level. The optimal conditions were determined and the adsorption isotherms, kinetics, and thermodynamic calculations were also done. In order to have detailed knowledge about metal biosorption, SEM, FTIR, and BET analyses were carried out before and after the biosorption process. The optimal pH was found pH 4 and the maximum metal uptake capacity was found as 0.067 mol kg-1. The results of this study indicate that the lichen was effectively applied to the removal of Pb2+ process as an inexpensive biosorbent from industrial wastewater.


Assuntos
Chumbo/isolamento & purificação , Líquens/metabolismo , Parmeliaceae/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Cinética , Chumbo/metabolismo , Líquens/química , Microscopia Eletrônica de Varredura , Modelos Teóricos , Parmeliaceae/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Turquia , Poluentes Químicos da Água/metabolismo
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