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  1 / 1024 MEDLINE  
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PMID:29175398
Autor:Qiu N; Wang R; Sun Y; Wang X; Jiang D; Meng Y; Zhou F
Endereço:School of Life Science, Qufu Normal University, Qufu, Shandong 273165, China.
Título:Toxic effects and mechanism of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) on Lemna minor.
Fonte:Chemosphere; 193:711-719, 2018 Feb.
ISSN:1879-1298
País de publicação:England
Idioma:eng
Resumo:To investigate the toxic effect and mechanism of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in aquatic plants, in vivo and in vitro exposure to BDE-47 were conducted. After 14-d exposure to 5-20 µg/L BDE-47, the growth of Lemna minor plants was significantly suppressed, and the chlorophyll and soluble protein contents in fronds markedly decreased. Accordingly, the photosynthetic efficiency (Fv/Fm, PI) decreased. When the thylakoid membranes isolated from healthy fronds was exposed to 5-20 mg/L BDE-47 directly in vitro for 1 h, the photosynthetic efficiency also decreased significantly. In both the in vitro (5-20 µg/L) and in vivo (5-20 mg/L) experiments, BDE-47 led to an increased plasma membrane permeability. Hence, we concluded that BDE-47 had a direct toxicity to photosynthetic membranes and plasma membranes. However, direct effects on the activities of peroxidase (POD), malate dehydrogenase (MDH) and nitroreductase (NR) were not observed by adding 5-20 mg/L BDE-47 into crude enzyme extracts. The malondialdehyde (MDA) and superoxide anion radical (O ) contents in the BDE-47 treated fronds were higher than those in the control fronds, suggesting that L. minor can not effectively relieve reactive oxygen species (ROS). The data above indicates that BDE-47 is toxic to L. minor through acting directly on biomembranes, which induces the production of ROS and thus causes remarkable oxidative damage to cells.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Halogenated Diphenyl Ethers); 0 (Reactive Oxygen Species); 0 (Water Pollutants, Chemical); 0F5N573A2Y (Ether); 0N97R5X10X (2,2',4,4'-tetrabromodiphenyl ether); 1406-65-1 (Chlorophyll); 4Y8F71G49Q (Malondialdehyde); EC 1.11.1.7 (Peroxidase)


  2 / 1024 MEDLINE  
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PMID:28858706
Autor:Modlitbová P; Novotný K; Porízka P; Klus J; Lubal P; Zlámalová-Gargosová H; Kaiser J
Endereço:Central European Institute of Technology (CEITEC) Brno University of Technology, Technická 3058/10, 616 00 Brno, Czech Republic. Electronic address: Pavlina.Skarkova@ceitec.vutbr.cz.
Título:Comparative investigation of toxicity and bioaccumulation of Cd-based quantum dots and Cd salt in freshwater plant Lemna minor L.
Fonte:Ecotoxicol Environ Saf; 147:334-341, 2018 Jan.
ISSN:1090-2414
País de publicação:Netherlands
Idioma:eng
Resumo:The purpose of this study was to determine the toxicity of two different sources of cadmium, i.e. CdCl and Cd-based Quantum Dots (QDs), for freshwater model plant Lemna minor L. Cadmium telluride QDs were capped with two coating ligands: glutathione (GSH) or 3-mercaptopropionic acid (MPA). Growth rate inhibition and final biomass inhibition of L. minor after 168-h exposure were monitored as toxicity endpoints. Dose-response curves for Cd toxicity and EC50 values were statistically evaluated for all sources of Cd to uncover possible differences among the toxicities of tested compounds. Total Cd content and its bioaccumulation factors (BAFs) in L. minor after the exposure period were also determined to distinguish Cd bioaccumulation patterns with respect to different test compounds. Laser-Induced Breakdown Spectroscopy (LIBS) with lateral resolution of 200µm was employed in order to obtain two-dimensional maps of Cd spatial distribution in L. minor fronds. Our results show that GSH- and MPA-capped Cd-based QDs have similar toxicity for L. minor, but are significantly less toxic than CdCl . However, both sources of Cd lead to similar patterns of Cd bioaccumulation and distribution in L. minor fronds. Our results are in line with previous reports that the main mediators of Cd toxicity and bioaccumulation in aquatic plants are Cd ions dissolved from Cd-based QDs.
Tipo de publicação: COMPARATIVE STUDY; JOURNAL ARTICLE
Nome de substância:0 (Cadmium Compounds); 0 (Water Pollutants, Chemical); B03TJ3QU9M (3-Mercaptopropionic Acid); GAN16C9B8O (Glutathione); J6K4F9V3BA (Cadmium Chloride); NQA0O090ZJ (Tellurium); STG188WO13 (cadmium telluride)


  3 / 1024 MEDLINE  
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PMID:28987404
Autor:Xu H; Yu C; Xia X; Li M; Li H; Wang Y; Wang S; Wang C; Ma Y; Zhou G
Endereço:Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Engineering Research Center of Biomass Resources and Environment, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.
Título:Comparative transcriptome analysis of duckweed (Landoltia punctata) in response to cadmium provides insights into molecular mechanisms underlying hyperaccumulation.
Fonte:Chemosphere; 190:154-165, 2018 Jan.
ISSN:1879-1298
País de publicação:England
Idioma:eng
Resumo:Cadmium (Cd) is a detrimental environmental pollutant. Duckweeds have been considered promising candidates for Cd phytoremediation. Although many physiological studies have been conducted, the molecular mechanisms underlying Cd hyperaccumulation in duckweeds are largely unknown. In this study, clone 6001 of Landoltia punctata, which showed high Cd tolerance, was obtained by large-scale screening of over 200 duckweed clones. Subsequently, its growth, Cd flux, Cd accumulation, and Cd distribution characteristics were investigated. To further explore the global molecular mechanism, a comprehensive transcriptome analysis was performed. For RNA-Seq, samples were treated with 20 µM CdCl for 0, 1, 3, and 6 days. In total, 9,461, 9,847, and 9615 differentially expressed unigenes (DEGs) were discovered between Cd-treated and control (0 day) samples. DEG clustering and enrichment analysis identified several biological processes for coping with Cd stress. Genes involved in DNA repair acted as an early response to Cd, while RNA and protein metabolism would be likely to respond as well. Furthermore, the carbohydrate metabolic flux tended to be modulated in response to Cd stress, and upregulated genes involved in sulfur and ROS metabolism might cause high Cd tolerance. Vacuolar sequestration most likely played an important role in Cd detoxification in L. punctata 6001. These novel findings provided important clues for molecular assisted screening and breeding of Cd hyperaccumulating cultivars for phytoremediation.
Tipo de publicação: COMPARATIVE STUDY; JOURNAL ARTICLE
Nome de substância:00BH33GNGH (Cadmium)


  4 / 1024 MEDLINE  
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PMID:29478632
Autor:Movafeghi A; Khataee A; Abedi M; Tarrahi R; Dadpour M; Vafaei F
Endereço:Department of Plant Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz 51666-16471, Iran. Electronic address: movafeghi@tabrizu.ac.ir.
Título:Effects of TiO nanoparticles on the aquatic plant Spirodela polyrrhiza: Evaluation of growth parameters, pigment contents and antioxidant enzyme activities.
Fonte:J Environ Sci (China); 64:130-138, 2018 Feb.
ISSN:1001-0742
País de publicação:Netherlands
Idioma:eng
Resumo:Plants are essential components of all ecosystems and play a critical role in environmental fate of nanoparticles. However, the toxicological impacts of nanoparticles on plants are not well documented. Titanium dioxide nanoparticles (TiO -NPs) are produced worldwide in large quantities for a wide range of purposes. In the present study, the uptake of TiO -NPs by the aquatic plant Spirodela polyrrhiza and the consequent effects on the plant were evaluated. Initially, structural and morphological characteristics of the used TiO -NPs were determined using XRD, SEM, TEM and BET techniques. As a result, an anatase structure with the average crystalline size of 8nm was confirmed for the synthesized TiO -NPs. Subsequently, entrance of TiO -NP to plant roots was verified by fluorescence microscopic images. Activity of a number of antioxidant enzymes, as well as, changes in growth parameters and photosynthetic pigment contents as physiological indices were assessed to investigate the effects of TiO -NPs on S. polyrrhiza. The increasing concentration of TiO -NPs led to the significant decrease in all of the growth parameters and changes in antioxidant enzyme activities. The activity of superoxide dismutase enhanced significantly by the increasing concentration of TiO -NPs. Enhancement of superoxide dismutase activity could be explained as promoting antioxidant system to scavenging the reactive oxygen species. In contrast, the activity of peroxidase was notably decreased in the treated plants. Reduced peroxidase activity could be attributed to either direct effect of these particles on the molecular structure of the enzyme or plant defense system damage due to reactive oxygen species.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Antioxidants); 0 (Water Pollutants, Chemical); 15FIX9V2JP (titanium dioxide); D1JT611TNE (Titanium); EC 1.11.1.7 (Peroxidase); EC 1.15.1.1 (Superoxide Dismutase)


  5 / 1024 MEDLINE  
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PMID:25839116
Autor:Karadeniz A; Alexie G; Greten HJ; Andersch K; Efferth T
Endereço:Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, Johannes Gutenberg University, Mainz, Germany; Mehmet Akif Ersoy University, Biology Department, Burdur, Turkey.
Título:Cytotoxicity of medicinal plants of the West-Canadian Gwich׳in Native Americans towards sensitive and multidrug-resistant cancer cells.
Fonte:J Ethnopharmacol; 168:191-200, 2015 Jun 20.
ISSN:1872-7573
País de publicação:Ireland
Idioma:eng
Resumo:ETHNOPHARMACOLOGICAL RELEVANCE: Traditional medicine of the Native Americans has a long tradition of medicinal plants, which also influenced modern oncology. For instance, podophyllotoxin the active ingredient of Podophyllum peltatum L. (Berberidaceae) used by Native Americans to treat warts led to the development of etoposide and teniposide. In the present investigation, we studied 10 medicinal plants used by the Gwich׳in First Nation of West-Canada, which have been used against diverse diseases including cancer. MATERIAL AND METHODS: Sensitive and multidrug-resistant (MDR) tumor cell lines expressing various ATP-binding cassette (ABC) transporters (P-glycoprotein/ABCB1/MDR1, MRP1/ABCC1, or BCRP/ABCG2) have been used. Cytotoxicity was determined by the resazurin assay. RESULTS: Arctium minus Bernh. (Asteraceae). Lysichiton americanus Hultén & St. John (Araceae), and Maianthemum dilatatum (Alph.Wood) A.Nelson & J.F.Macbr.(Asparagaceae) were cytotoxic with IC50 values ranging from 2.40 to 86.35 µg/mL. The MDR cell lines did not exert cross-resistance to these extracts. CONCLUSION: As these medicinal plants of the West-Canadian Gwich׳in First Nation were not involved in classical drug resistance mechanisms and might therefore be valuable to bypass anticancer drug resistance in refractory tumors.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (ATP-Binding Cassette Transporters); 0 (Antineoplastic Agents); 0 (Plant Extracts)


  6 / 1024 MEDLINE  
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PMID:28882671
Autor:Yu J; Song X; Wang D; Wang X; Wang X
Endereço:Shandong Key Laboratory of TCM Quality Control Technology, Shandong Analysis and Test Center, Jinan 250014, PR China.
Título:Five new chromone glycosides from Scindapsus officinalis (Roxb.) Schott.
Fonte:Fitoterapia; 122:101-106, 2017 Oct.
ISSN:1873-6971
País de publicação:Netherlands
Idioma:eng
Resumo:Five new chromone glycosides, officinalisides A (1), B (2), C (3), D (4) and E (5) were isolated from Scindapsus officinalis (Roxb.) Schott., along with six known chromone derivatives, 7-O-α-l-rhamnosyl-nereugenin (6), undulatoside A (7), drynachromoside A (8), drynachromoside B (9), 5,7-dihydroxy-2-methyl chromone(10), 5,7-dihydroxy-2-hydroxymethyl chromone (11). Structural elucidation of the isolated compounds was established by spectroscopic analysis, especially 2D NMR techniques and comparison with literatures. The isolates were evaluated for anti-inflammatory activities in a LPS-stimulated RAW 264.7 model using inhibition of nitric oxide (NO) production as an indicator. Compounds 2, 4 and 10 demonstrated potential anti-inflammatory activity with IC values of 16.1, 19.1, and 13.4µM, respectively, compared to the positive control dexamethasone.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Anti-Inflammatory Agents); 0 (Chromones); 0 (Glycosides); 31C4KY9ESH (Nitric Oxide)


  7 / 1024 MEDLINE  
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PMID:28644992
Autor:Zou X; Li P; Lou J; Zhang H
Endereço:Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China.
Título:Surface coating-modulated toxic responses to silver nanoparticles in Wolffia globosa.
Fonte:Aquat Toxicol; 189:150-158, 2017 Aug.
ISSN:1879-1514
País de publicação:Netherlands
Idioma:eng
Resumo:With the omnipresence of silver nanoparticles (AgNPs) in our daily consumer products, their release has raised serious concerns. However, the biochemical mechanisms by which plants counteract the toxicity of nanoparticles are largely unknown. This study investigated the exposure of aquatic Wolffia globosa to ATP-nAg (AgNPs coated with adenosine triphosphate), cit-nAg (AgNPs coated with citrate), and Ag . Hill reaction activity was basically lost in W. globosa treated with 10mg/L ATP-nAg and Ag , while the activity was still maintained at 38.7%-38.9% of the respective controls at 10mg/L cit-nAg. The reduction of amounts of chlorophyll and soluble protein were shown in response to the Ag stresses. This was accompanied by the accumulation of sugar in W. globosa treated with cit-nAg. By contrast, the depletion of sugar was recorded after 10mg/L ATP-nAg and Ag treatments. The superoxide dismutase and peroxidase activities were significantly increased after exposure to 10mg/L ATP-nAg and Ag , which did not occurred in W. globosa treated with cit-nAg. The ratio between NADPH/NADP was higher after cit-nAg and Ag stresses than the respective controls. The accumulation of Ag was found to increase in a concentration-dependent manner. Ag and ATP-nAg inhibited the uptake of P and K, and promoted the uptake of Fe and Cu. In contrast, cit-nAg only promoted the uptake of Cu. Our results implied that surface coating induced different physiological responses of W. globosa to AgNPs. Based on above results, we speculated that after exposure to cit-nAg, citrate possibly could serve as the substrate for the tricarboxylic acid cycle and accumulated sugar may promote pentose phosphate pathways. For ATP-nAg treatments, ATP would act as an exogenous energy source of plant metabolisms. Our findings demonstrate that surface coating regulates the physiological responses of plants to AgNPs through distinct mechanisms.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Antioxidants); 0 (Water Pollutants, Chemical); 1406-65-1 (Chlorophyll); 2968PHW8QP (Citric Acid); 3M4G523W1G (Silver); EC 1.15.1.1 (Superoxide Dismutase)


  8 / 1024 MEDLINE  
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PMID:28550805
Autor:Wang F; Yi X; Qu H; Chen L; Liu D; Wang P; Zhou Z
Endereço:Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing 100193, PR China.
Título:Enantioselective accumulation, metabolism and phytoremediation of lactofen by aquatic macrophyte Lemna minor.
Fonte:Ecotoxicol Environ Saf; 143:186-192, 2017 Sep.
ISSN:1090-2414
País de publicação:Netherlands
Idioma:eng
Resumo:Pesticides are frequently detected in water bodies due to the agricultural application, which may pose impacts on aquatic organisms. The enantioselective bioaccumulation and metabolism of the herbicide lactofen in aquatic floating macrophyte Lemna minor (L. minor) were studied and the potential L. minor phytoremediation was investigated. Ultra-high performance liquid chromatography - tandem mass spectrometry (UHPLC-MS-MS) analysis for lactofen and its two known metabolites in L. minor was performed. The initial concentrations of racemic lactofen, R-lactofen and S-lactofen were all 30µgL in the growth solution. The distribution of lactofen and its metabolites in growth solution and L. minor was determined throughout a 5-d laboratory trial. It was observed that S-lactofen was preferentially taken up and metabolized in L. minor. After rac-lactofen exposure, the accumulation amount of S-lactofen was approximately 3-fold more than that of R-lactofen in L. minor and the metabolism rate of S-lactofen (T =0.92 d) was significantly faster than R-lactofen (T =1.55 d). L. minor could only slightly accelerate the metabolism and removal of lactofen in the growth solution. As for the metabolites, desethyl lactofen was found to be the major metabolite in L. minor and the growth solution, whereas the metabolite acifluorfene was undetectable. No interconversion of the two enantiomers was observed after individual enantiomer exposure, indicating they were configurationally stable. The findings of this work represented that the accumulation and metabolism of lactofen in L. minor were enantioselective, and L. minor had limited capacity for the removal of lactofen and its metabolite in water.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Halogenated Diphenyl Ethers); 0 (Herbicides); L44N8UV47O (lactofen)


  9 / 1024 MEDLINE  
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PMID:28500894
Autor:Zhang T; Lu Q; Su C; Yang Y; Hu D; Xu Q
Endereço:College of Life Science, Nanjing Normal University, Nanjing 210023, PR China.
Título:Mercury induced oxidative stress, DNA damage, and activation of antioxidative system and Hsp70 induction in duckweed (Lemna minor).
Fonte:Ecotoxicol Environ Saf; 143:46-56, 2017 Sep.
ISSN:1090-2414
País de publicação:Netherlands
Idioma:eng
Resumo:Mercury uptake and its effects on physiology, biochemistry and genomic stability were investigated in Lemna minor after 2 and 6d of exposure to 0-30µM Hg. The accumulation of Hg increased in a concentration- and duration-dependent manner, and was positively correlated with the leaf damage. Oxidative stress after Hg exposure was evidenced in L. minor by a significant decrease in photosynthetic pigments, an increase in malondialdehyde and lipoxygenase activities (total enzyme activity and isoenzymes activity). Fronds of L. minor exposed to Hg showed an induction of peroxidase, catalase, and ascorbate peroxidase activities (total enzyme activity and some isoenzymes activities). Exposure of L. minor to Hg reduced the activity (total enzyme activity and some isoenzymes activities) of glutathione reductase, and superoxide dismutase. Exposure to Hg produced a transient increase in the content of glutathione and ascorbic acid. The content of dehydroascorbate and oxidized glutathione in L. minor were high during the entire exposure period. Exposure of L. minor to Hg also caused the accumulation of proline and soluble sugars. The amplification of new bands and the absence of normal DNA amplicons in treated plants in the random amplified polymorphic DNA (RAPD) profile indicated that genomic template stability (GTS) was affected by Hg treatment. The accumulation of Hsp70 indicated the occurrence of a heat shock response at all Hg concentrations. These results suggest that L. minor plants were able to cope with Hg toxicity through the activation of various mechanisms involving enzymatic and non-enzymatic antioxidants, up-regulation of proline, and induction of Hsp70.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Antioxidants); 0 (HSP70 Heat-Shock Proteins); 0 (Water Pollutants, Chemical); 9DLQ4CIU6V (Proline); FXS1BY2PGL (Mercury)


  10 / 1024 MEDLINE  
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PMID:28498121
Autor:Ferreira RM; Domingues ALC; Takase I; Stapelfeldt DMA
Endereço:Graduate Program in Environmental Science and Conservation, Federal University of Rio de Janeiro, Macaé, RJ, Brazil E-mail: rachelmoraes@hotmail.com.br.
Título:Studies of selective adsorption, desorption and reuse of chemically altered biomass produced from aquatic macrophytes for treatment of metal-containing wastewater.
Fonte:Water Sci Technol; 75(9-10):2083-2093, 2017 May.
ISSN:0273-1223
País de publicação:England
Idioma:eng
Resumo:The aquatic macrophytes Salvinia sp. and Pistia stratiotes have a natural capacity to adsorb various elements, including heavy metals. This capacity was enhanced with a chemical treatment using NaOH alkaline solution for Salvinia sp. and a mixture of both Salvinia sp. and Pistia stratiotes at a proportion of 1:1, whose respective biosorbents were called SSOH and MBOH. Adsorption tests were done in a ternary system containing the metals copper, lead and manganese; the parameters considered were: starting concentration, kinetics, pH and temperature. The adsorption isotherms for SSOH had a maximum adsorptive capacity of 50.20, 53.85 and 14.68 mg g for Cu, Pb and Mn, respectively; for MBOH, maximum values were 44.62, 35.17 and 15.74 mg g for Cu, Pb and Mn, respectively. The metals displayed different behaviors with pH variation. The results also showed an adsorption preference of Cu > Pb > Mn for SSOH. Desorption and readsorption studies were also carried out, showing 100% desorption and increased adsorption capacity in readsorption tests. Surface area and porosity analysis with the Brunauer-Emmett-Teller (BET) method indicate that after chemical modification, MBOH and SSOH biomasses had their surface increased in comparison to SS, with values of 165.5657 (MBOH), 157.4392 (SSOH) and 78.9432 m g (SS).
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Metals, Heavy); 0 (Waste Water); 0 (Water Pollutants, Chemical)



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