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Ágnes M. Móricz - One of the best experts on this subject based on the ideXlab platform.
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Investigation of antibacterial and cytotoxic potential of phenolics derived from Cistus incanus L. by means of thin-layer chromatography-direct bioautography and cytotoxicity assay
Journal of Liquid Chromatography & Related Technologies, 2018Co-Authors: Dariusz Szeremeta, Magdalena Knaś, Ewa Długosz, Klaudia Krzykała, Anna Mrozek-wilczkiewicz, Robert Musiol, Teresa Kowalska, Mieczysław Sajewicz, Ágnes M. MóriczAbstract:ABSTRACTCistus incanus L. (hairy rockrose) is a medicinal plant which belongs to the Cistaceae family and the Cistus genus, with a well established position in traditional medicine of the Mediterranean basin and the Middle East. It was the aim of this study to compare antibacterial activity of the phenolics derived from fourteen C. incanus samples of different origin (Turkey, Albania, Greece, and an unknown geographical location) obtained as herbal teas from a local market of diet supplements. This activity was assessed with the use of thin-layer chromatography–direct bioautography (TLC-DB) applied to crude extracts against the Gram negative naturally luminescent marine bacterium Aliivibrio fischeri and the Gram positive soil bacterium Bacillus subtilis as the test microorganisms. It was established that in spite of different origin of the investigated herbal samples, in qualitative terms their antibacterial activity was closely comparable and more strongly pronounced against the Gram positive than the Gr...
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Effect-directed analysis via hyphenated high-performance thin-layer chromatography for bioanalytical profiling of sunflower leaves
Journal of Chromatography A, 2017Co-Authors: Ágnes M. Móricz, Imanuel Yüce, András Darcsi, Szabolcs Béni, Gertrud E. MorlockAbstract:Abstract High-performance thin-layer chromatography (HPTLC) coupled with effect-directed analysis was used for non-targeted screening of sunflower leaf extract for components exhibiting antioxidant, antibacterial and/or cholinesterase enzyme inhibitory effects. The active compounds were characterized by HPTLC-electrospray ionization-high resolution mass spectrometry (ESI-HRMS) and HPTLC-Direct Analysis in Real Time (DART)-MS/MS. The latter ambient ionization technique (less soft than ESI) resulted in oxidation and fragmentation products and characteristic fragment ions. NMR spectroscopy after targeted isolation via preparative normal phase flash chromatography and semi-preparative reversed phase high-performance liquid chromatography supported the identification of two diterpenes to be (-)-kaur-16-en-19-oic acid and 15-α-angeloyloxy-ent-kaur-16-en-19-oic acid. Both compounds found to be multi-potent as they inhibited acetylcholinesterase and butyrylcholinesterase and showed antibacterial effects against Gram-positive Bacillus subtilis and Gram-negative Aliivibrio fischeri bacteria. Kaurenoic acid was also active against the Gram-negative pepper pathogenic Xanthomonas euvesicatoria bacteria.
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Separation and Detection of Bioactive Essential Oil Components by Overpressured Layer Chromatography Coupled with Bioactivity Tests
JPC – Journal of Planar Chromatography – Modern TLC, 2017Co-Authors: Ágnes M. Móricz, Dániel KrüzselyiAbstract:Overpressured layer chromatography (OPLC), ensuring pumpforced constant mobile phase flow and the possibility of overrun, offers the expanded exploitation of fine-particle adsorbent layers for a longer development distance. Using an infusion—transfusion OPLC method with a 26-cm long development, the separation of clove, rosemary, eucalyptus, tea tree, spearmint, thyme, and cinnamon bark essential oil components was achieved with good resolutions. In the combination of OPLC and Aliivibrio fischeri assay, the main essential oil components eugenol, borneol, (−)-R-carvone, thymol, and trans -cinnamaldehyde exhibited antibacterial effect. The OPLC—2,2-diphenyl-1-picrylhydrazyl (DPPH*) test showed two antioxidant components: eugenol and thymol.
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Screening of antibacterial compounds in thymus vulgaris l. tincture using thin-layer chromatography-direct bioautography and liquid chromatography-tandem mass spectrometry techniques
Jpc-journal of Planar Chromatography-modern Tlc, 2017Co-Authors: Wioleta Jesionek, Ágnes M. Móricz, Györgyi Horváth, Barbara Majer-dziedzic, Irena M ChomaAbstract:In this study, thin-layer chromatography—direct bioautography (TLC—DB) was used for guiding the isolation and identification of antibacterial constituents of Thymus vulgaris L. ethanol extract. This TLC—bioassay method enables the separation and detection of active components directly on the surface of chromatographic plates. They can be identified by comparison with reference substances or using physicochemical methods, preferably spectroscopic ones (liquid chromatography—tandem mass spectrometry [LC—MS/MS], in the presented paper). The described method belongs to the effect-directed analyses (EDA). Seven bacterial strains were used as test organisms, both pathogenic and nonpathogenic, including methicillin-resistant Staphylococcus aureus as well as luminescent bacteria like Aliivibrio fischeri. Five fractions with the widest antimicrobial spectra were detected using TLC—DB, isolated by semi-preparative TLC and subjected to LC—MS/MS analyses. Finally, two bioactive components were tentatively identified,...
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Screening of Antibacterial Compounds in Thymus vulgaris L. Tincture Using Thin-Layer Chromatography—Direct Bioautography and Liquid Chromatography—Tandem Mass Spectrometry Techniques
JPC – Journal of Planar Chromatography – Modern TLC, 2017Co-Authors: Wioleta Jesionek, Ágnes M. Móricz, Györgyi Horváth, Barbara Majer-dziedzic, Irena M ChomaAbstract:In this study, thin-layer chromatography—direct bioautography (TLC—DB) was used for guiding the isolation and identification of antibacterial constituents of Thymus vulgaris L. ethanol extract. This TLC—bioassay method enables the separation and detection of active components directly on the surface of chromatographic plates. They can be identified by comparison with reference substances or using physicochemical methods, preferably spectroscopic ones (liquid chromatography—tandem mass spectrometry [LC—MS/MS], in the presented paper). The described method belongs to the effect-directed analyses (EDA). Seven bacterial strains were used as test organisms, both pathogenic and nonpathogenic, including methicillin-resistant Staphylococcus aureus as well as luminescent bacteria like Aliivibrio fischeri . Five fractions with the widest antimicrobial spectra were detected using TLC—DB, isolated by semi-preparative TLC and subjected to LC—MS/MS analyses. Finally, two bioactive components were tentatively identified, basing on their fragmentation pattern, as eriodictyol and 4,4′-dihydroxy-5,5′-diisopropyl-2,2′-dimethyl-3,6-bifenylodion.
Irena M Choma - One of the best experts on this subject based on the ideXlab platform.
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Screening of Antibacterial Compounds in Thymus vulgaris L. Tincture Using Thin-Layer Chromatography—Direct Bioautography and Liquid Chromatography—Tandem Mass Spectrometry Techniques
JPC – Journal of Planar Chromatography – Modern TLC, 2017Co-Authors: Wioleta Jesionek, Ágnes M. Móricz, Györgyi Horváth, Barbara Majer-dziedzic, Irena M ChomaAbstract:In this study, thin-layer chromatography—direct bioautography (TLC—DB) was used for guiding the isolation and identification of antibacterial constituents of Thymus vulgaris L. ethanol extract. This TLC—bioassay method enables the separation and detection of active components directly on the surface of chromatographic plates. They can be identified by comparison with reference substances or using physicochemical methods, preferably spectroscopic ones (liquid chromatography—tandem mass spectrometry [LC—MS/MS], in the presented paper). The described method belongs to the effect-directed analyses (EDA). Seven bacterial strains were used as test organisms, both pathogenic and nonpathogenic, including methicillin-resistant Staphylococcus aureus as well as luminescent bacteria like Aliivibrio fischeri . Five fractions with the widest antimicrobial spectra were detected using TLC—DB, isolated by semi-preparative TLC and subjected to LC—MS/MS analyses. Finally, two bioactive components were tentatively identified, basing on their fragmentation pattern, as eriodictyol and 4,4′-dihydroxy-5,5′-diisopropyl-2,2′-dimethyl-3,6-bifenylodion.
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Screening of antibacterial compounds in thymus vulgaris l. tincture using thin-layer chromatography-direct bioautography and liquid chromatography-tandem mass spectrometry techniques
Jpc-journal of Planar Chromatography-modern Tlc, 2017Co-Authors: Wioleta Jesionek, Ágnes M. Móricz, Györgyi Horváth, Barbara Majer-dziedzic, Irena M ChomaAbstract:In this study, thin-layer chromatography—direct bioautography (TLC—DB) was used for guiding the isolation and identification of antibacterial constituents of Thymus vulgaris L. ethanol extract. This TLC—bioassay method enables the separation and detection of active components directly on the surface of chromatographic plates. They can be identified by comparison with reference substances or using physicochemical methods, preferably spectroscopic ones (liquid chromatography—tandem mass spectrometry [LC—MS/MS], in the presented paper). The described method belongs to the effect-directed analyses (EDA). Seven bacterial strains were used as test organisms, both pathogenic and nonpathogenic, including methicillin-resistant Staphylococcus aureus as well as luminescent bacteria like Aliivibrio fischeri. Five fractions with the widest antimicrobial spectra were detected using TLC—DB, isolated by semi-preparative TLC and subjected to LC—MS/MS analyses. Finally, two bioactive components were tentatively identified,...
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TLC-direct bioautography as a bioassay guided method for investigation of antibacterial compounds in Hypericum perforatum L.
Journal of AOAC International, 2015Co-Authors: Wioleta Jesionek, Byula Kocsis, Ágnes M. Móricz, Györgyi Horváth, Ágnes Alberti, Irena M ChomaAbstract:Fast high-throughput TLC-direct bioautography (DB) is an effect-directed analysis method that enables searching for biologically active (e.g., antimicrobial) substances in complex mixtures like plant extracts. The principle of the method is that separation and detection of biological properties of given mixture components is performed directly on a TLC plate. In searching for antibacterial activity, the developed plate is immersed in a bacterial broth, and bacteria grow directly on its layer during a proper incubation time. Inhibition zones are formed in places where antimicrobial components are located. The active compounds can be further identified using spectroscopic techniques. The aim of our study was investigation of plant components of Hypericum perforatum L. tincture by TLC-DB using nine bacterial strains: Micrococcus luteus, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, methicillin-resistant S. aureus, S. epidermidis, Pseudomonas syringae pv. maculicola, Xanthomonas campestris pv. vesicatoria, and Aliivibrio fischeri. Compounds showing the widest range of antimicrobial activity were isolated using semipreparative TLC and identified as apigenin, 3,8'-biapigenin, quercetin, kaempferol, and linolenic acid by TLC, HPLC-diode array detection, and HPLC/MS/MS techniques.
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TLC-direct bioautography and LC/MS as complementary methods in identification of antibacterial agents in plant tinctures from the asteraceae family
Journal of AOAC International, 2015Co-Authors: Wioleta Jesionek, Byula Kocsis, Ágnes M. Móricz, Péter G. Ott, Györgyi Horváth, Irena M ChomaAbstract:Matricaria recutita L. (chamomile) and Achillea millefolium L. (yarrow) are very common herbs growing in meadows, pathways, crop fields, and home gardens. Preparations from these plants, e.g., infusions or alcohol extracts, are widely used as remedies. Both chamomile and yarrow have anti-inflammatory, analgesic, antimicrobial, and antioxidant properties. Most microbiological assays used today give information only on activity of whole extracts and do not provide information on the composition and activity of individual components. This problem can be solved by using TLC with direct microbiological detection, i.e., TLC-direct bioautography (TLC-DB), followed by LC/MS of active fractions. The aim of our study was chemical and microbiological screening of plant components of chamomile and yarrow tinctures using derivatization reagents and TLC-DB against eight bacterial strains: Staphylococcus epidermidis, S. aureus, methicillin-resistant S. aureus, Escherichia coli, Pseudomonas syringae pv. maculicola, Xanthomonas campestis pv. vesicatoria, Aliivibrio fischeri, and Bacillus subtilis. The identity of compounds exhibiting the widest range of activity (apigenin and α-linolenic acid) was confirmed by LC/MS.
Gertrud E. Morlock - One of the best experts on this subject based on the ideXlab platform.
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Effect-Directed Analysis of Pimpinella saxifraga L. Root Extract via HPTLC—UV/Vis/FLD—EDA—MS
JPC – Journal of Planar Chromatography – Modern TLC, 2018Co-Authors: Gertrud E. Morlock, Tatjana LapinAbstract:A method was developed for effect-directed analysis (EDA) of the root extract of Pimpinella saxifraga L. High-performance thin-layer chromatography (HPTLC) was hyphenated with microchemical, biochemical, and biological assays as well as electrospray ionization—mass spectrometry (ESI—MS). This HPTLC—UV/Vis/FLD—EDA—MS method directly pointed to multi-potent compounds in the P. saxifraga L. root extract. 2,2-Diphenyl-1-picrylhydrazyl radical scavengers, acetylcholinesterase inhibitors, estrogen-effective compounds, antimicrobials against Gram-positive Bacillus subtilis bacteria, and Gram-negative Aliivibrio fischeri bacteria were discovered in the root extract. A first targeted characterization of four unknown multi-potent compounds was performed by HPTLC—ESI—MS and microchemical derivatizations. This highly streamlined effect-directed profiling is recommended for a fast and cost-efficient natural product search.
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Effect-directed analysis via hyphenated high-performance thin-layer chromatography for bioanalytical profiling of sunflower leaves
Journal of Chromatography A, 2017Co-Authors: Ágnes M. Móricz, Imanuel Yüce, András Darcsi, Szabolcs Béni, Gertrud E. MorlockAbstract:Abstract High-performance thin-layer chromatography (HPTLC) coupled with effect-directed analysis was used for non-targeted screening of sunflower leaf extract for components exhibiting antioxidant, antibacterial and/or cholinesterase enzyme inhibitory effects. The active compounds were characterized by HPTLC-electrospray ionization-high resolution mass spectrometry (ESI-HRMS) and HPTLC-Direct Analysis in Real Time (DART)-MS/MS. The latter ambient ionization technique (less soft than ESI) resulted in oxidation and fragmentation products and characteristic fragment ions. NMR spectroscopy after targeted isolation via preparative normal phase flash chromatography and semi-preparative reversed phase high-performance liquid chromatography supported the identification of two diterpenes to be (-)-kaur-16-en-19-oic acid and 15-α-angeloyloxy-ent-kaur-16-en-19-oic acid. Both compounds found to be multi-potent as they inhibited acetylcholinesterase and butyrylcholinesterase and showed antibacterial effects against Gram-positive Bacillus subtilis and Gram-negative Aliivibrio fischeri bacteria. Kaurenoic acid was also active against the Gram-negative pepper pathogenic Xanthomonas euvesicatoria bacteria.
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Planar chromatographic screening and quantification of coumarin in food, confirmed by mass spectrometry.
Food Chemistry, 2017Co-Authors: Stephanie Krüger, Luisa Winheim, Gertrud E. MorlockAbstract:Abstract A sensitive quantitative screening of coumarin in 43 commercially available cinnamons and cinnamon-containing foods was developed via HPTLC. Complex samples like cinnamon, tea, breakfast cereals, milk rice, jam, cinnamon stars and buns were extracted with methanol only. Separation was performed on silica gel with a mixture of n- hexane, ethyl acetate and ammonia. The specific detection via derivatization with an ethanolic potassium hydroxide solution resulted in fluorescent coumarin zones, measured at 365/>400 nm after stabilization. Limits of detection and quantification were 200 and 400 pg/band, respectively. Over all different sample types, the contents ranged from 0.3 to 5129 mg/kg with a mean repeatability and mean intermediate precision of 4% each. HPTLC-MS of selected zones, eluted via the TLC-MS Interface into MS, confirmed the identity of coumarin. Effect-directed detection as bioanalytical tool for risk assessment showed coumarin to be active against Aliivibrio fischeri bacteria down to 100 ng/band.
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From Bioprofiling and Characterization to Bioquantification of Natural Antibiotics by Direct Bioautography Linked to High-Resolution Mass Spectrometry: Exemplarily Shown for Salvia miltiorrhiza Root
Analytical Chemistry, 2016Co-Authors: Maryam Jamshidi-aidji, Gertrud E. MorlockAbstract:Phytochemicals are promising agents in the development of new antibiotics. A streamlined strategy for rapid screening and reliable characterization of antibiotics in botanicals was demonstrated in contrast to the commonly applied chromatographic column fractionation followed by microtiter plate assay. Modern direct bioautography hyphenated to structure elucidation techniques is a straightforward bioanalytical tool, especially if microbiological assays were taken into account. At one go, lipophilic antimicrobials in Salvia miltiorrhiza root samples were analyzed using high-performance thin-layer chromatography (HPTLC) in direct combination with Aliivibrio fischeri and Bacillus subtilis bioassays. The most intense antimicrobials were characterized via HPTLC-high-resolution mass spectrometry. As proof of this streamlined strategy, dihydrotanshinone, cryptotanshinone, and tanshinone IIA were identified and also compared with a reference. Two further antimicrobial zones in the bioautograms were tentatively ass...
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Layer-Induced Sensitivity Enhancement in Planar Chromatography–Bioluminescence–Mass Spectrometry: Application to Alkaloids
Chromatographia, 2016Co-Authors: Yisheng Chen, Gertrud E. MorlockAbstract:The use of amino phases induced a significant increase of the bioluminescence for the high-performance thin-layer chromatography (HPTLC)-Aliivibrio fischeri bioassay. By this, the detectability of alkaloids was improved. Detection limits at the low ng per zone level were obtained for the five alkaloids berberine, palmatine, ephedrine, norephedrine, and methylephedrine. The influence of other parameters on this effect, such as fluorescence indicators and pH milieu, was proven to be insignificant. This implied that propyl amino groups linked to the silica gel layer might play a pronounced role in the improved visualization mechanism. The optimized bioassay was applied for profiling of alkaloid-rich herbal drugs such as Philodendron, Coptis, Tinospora, and Ephedra, leading to information-rich biofingerprints. The direct coupling of HPTLC to electrospray ionization mass spectrometry enabled unambiguous and straightforward confirmation of the bioactive ingredients.
Antonio Finizio - One of the best experts on this subject based on the ideXlab platform.
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toxicity of individual pharmaceuticals and their mixtures to Aliivibrio fischeri evidence of toxicological interactions in binary combinations
Environmental Toxicology and Chemistry, 2017Co-Authors: Valeria Di Nica, S Villa, Antonio FinizioAbstract:The combined toxicities of binary mixtures of veterinary pharmaceuticals active compounds (PhACs) were examined using the bioluminescent bacterium Aliivibrio fischeri as a test organism (Microtox® test). Mixtures were prepared at an equitoxic ratio that corresponded to the IC10 of individual PhACs. In addition, we determined the toxicity of a multi-component mixture that contained all of the investigated PhACs mixed at the ratio corresponding to their individual values of Predicted No Effect Concentrations (PNEC). The experimental results were successively compared with those obtained by applying the two most widely used models for predicting mixture toxicity, i.e., the concentration addition (CA) and independent action (IA) models. Although the toxicity of the tested multi-component mixture was well predicted by the CA and IA models, deviations from the model predictions were found for almost all of the binary mixtures. The deviations from the CA and IA models were greater at lower concentrations, particularly when diclofenac sodium and amoxicillin were present in the mixture. Based on these results, we tested the hypothesis of toxicological interactions occurring in binary mixtures (in the direction of synergistic or antagonistic effects) by applying the Combination Index (CI) method, which allowed for the computerised quantisation of synergism, the additive effect and antagonism. The application of this method confirmed, for at least half of the binary combinations, the clear presence of synergistic deviations at the lowest tested concentrations, with a tendency towards antagonism at the higher ones. In one case, a relevant antagonistic interaction was observed. This article is protected by copyright. All rights reserved
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toxicity of individual pharmaceuticals and their mixtures to Aliivibrio fischeri experimental results for single compounds and considerations of their mechanisms of action and potential acute effects on aquatic organisms
Environmental Toxicology and Chemistry, 2017Co-Authors: Valeria Di Nica, S Villa, Antonio FinizioAbstract:In the first part of a broader study on the effects of individual and multicomponent mixtures of pharmaceutical active compounds, the authors used the Microtox® test system to analyze in detail the effects of 10 widely used human and veterinary pharmaceutical active compounds toward the bioluminescent bacterium Aliivibrio fischeri. The experimental results indicated moderate toxicity for the majority of the tested compounds. Comparison between experimental 50% inhibitory concentrations and those predicted from the quantitative structure-activity relationship models indicated that most of the tested pharmaceutical active compounds behave as polar narcotic compounds toward A. fischeri (only the antibiotic chlortetracycline seemed to have a specific mechanism of action). A comparison between the experimental results and a collection of acute toxicity data on other nontarget organisms indicated that in general A. fischeri has a comparable sensitivity to other aquatic species. However, according to the Globally Harmonized System of Classification and Labelling of Chemicals, the majority of the investigated chemicals can be classified as harmful or nontoxic for aquatic ecosystems. Finally, based on comparisons among the 95th percentile of measured environmental concentrations found in European Union water bodies and acute toxicity data on various aquatic organisms, no risk to aquatic life exists when the tested pharmaceutical active compounds are assessed as individual chemicals. Environ Toxicol Chem 2017;36:807-814. © 2016 SETAC.
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Toxicity of individual pharmaceuticals and their mixtures to Aliivibrio fischeri: Experimental results for single compounds, considerations of their mechanisms of action and potential acute effects on aquatic organisms
Environmental Toxicology and Chemistry, 2016Co-Authors: Valeria Di Nica, Sara Villa, Antonio FinizioAbstract:In the first part of a broader study on the effects of individual and multicomponent mixtures of pharmaceutical active compounds, the authors used the Microtox® test system to analyze in detail the effects of 10 widely used human and veterinary pharmaceutical active compounds toward the bioluminescent bacterium Aliivibrio fischeri. The experimental results indicated moderate toxicity for the majority of the tested compounds. Comparison between experimental 50% inhibitory concentrations and those predicted from the quantitative structure-activity relationship models indicated that most of the tested pharmaceutical active compounds behave as polar narcotic compounds toward A. fischeri (only the antibiotic chlortetracycline seemed to have a specific mechanism of action). A comparison between the experimental results and a collection of acute toxicity data on other nontarget organisms indicated that in general A. fischeri has a comparable sensitivity to other aquatic species. However, according to the Globally Harmonized System of Classification and Labelling of Chemicals, the majority of the investigated chemicals can be classified as harmful or nontoxic for aquatic ecosystems. Finally, based on comparisons among the 95th percentile of measured environmental concentrations found in European Union water bodies and acute toxicity data on various aquatic organisms, no risk to aquatic life exists when the tested pharmaceutical active compounds are assessed as individual chemicals. Environ Toxicol Chem 2017;36:807-814. © 2016 SETAC.
William Gerson Matias - One of the best experts on this subject based on the ideXlab platform.
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comparative assessment of acute and chronic ecotoxicity of water soluble fractions of diesel and biodiesel on daphnia magna and Aliivibrio fischeri
Chemosphere, 2019Co-Authors: Juliana Braun Muller, Silvia Pedroso Melegari, Francois Perreault, William Gerson MatiasAbstract:Abstract The widespread use of diesel as a transportation fuel and the introduction of biodiesel into the world energy matrix increase the likelihood of aquatic contamination with these fuels. In this case, it is important to know the environmental impacts caused by water-soluble fraction (WSF) of these fuels, since it is the portion that can result in long-term impacts and affect regions far away from the location of a spill. Therefore, we evaluated and compared the aquatic ecotoxicity of the WSF of biodiesel and diesel through acute ecotoxicity tests with the aquatic microcrustacean Daphnia magna and the marine bacteria Aliivibrio fischeri, as well as chronic ecotoxicity tests with D. magna. The WSF of diesel was 2.5–4 folds more toxic than the WSF of biodiesel in acute ecotoxicity tests. Similarly, a comparison of the chronic ecotoxicity demonstrated that the WSF of diesel was more toxic than the WSF of biodiesel. WSF of diesel causes chronic effects on reproduction, longevity and growth of D. magna (NOEC was 12.5, 12.5, 6.25%, respectively), while WSF of biodiesel did not present significantly different results compared to the control for any of the parameters evaluated in any of the dilutions tested (NOEC> 25%). To the best of our knowledge, this is the first study that compares the chronic ecotoxicity of WSF of diesel and biodiesel on D. magna.
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Correlation between acute toxicity for Daphnia magna, Aliivibrio fischeri and physicochemical variables of the leachate produced in landfill simulator reactors
Environmental Technology, 2017Co-Authors: José Julio Barrios Restrepo, Letícia Flohr, Silvia Pedroso Melegari, Cristina H. Da Costa, Cristiane Funghetto Fuzinatto, Armando Borges De Castilhos, William Gerson MatiasAbstract:ABSTRACTDue to the diversified nature of municipal solid waste and the different stages of its decomposition, the formed leachates result in a complex chemical mixture with toxic potential. These chemicals can cause environmental problems, such as the contamination of surface or groundwater, thus affecting the balance of aquatic ecosystems. The aim of our study was to evaluate the acute toxicity of leachates in Daphnia magna and Aliivibrio fischeri and to identify the main physicochemical variables that influence the toxicity of the landfill leachates produced in reactors within pilot simulations. Acute toxicity tests carried out on D. magna and A. fischeri showed that the leachates produced inside the reactors are highly toxic, presenting EC5048h
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correlation between acute toxicity for daphnia magna Aliivibrio fischeri and physicochemical variables of the leachate produced in landfill simulator reactors
Environmental Technology, 2017Co-Authors: José Julio Barrios Restrepo, Letícia Flohr, Silvia Pedroso Melegari, Cristina H. Da Costa, Cristiane Funghetto Fuzinatto, Armando Borges De Castilhos, William Gerson MatiasAbstract:ABSTRACTDue to the diversified nature of municipal solid waste and the different stages of its decomposition, the formed leachates result in a complex chemical mixture with toxic potential. These chemicals can cause environmental problems, such as the contamination of surface or groundwater, thus affecting the balance of aquatic ecosystems. The aim of our study was to evaluate the acute toxicity of leachates in Daphnia magna and Aliivibrio fischeri and to identify the main physicochemical variables that influence the toxicity of the landfill leachates produced in reactors within pilot simulations. Acute toxicity tests carried out on D. magna and A. fischeri showed that the leachates produced inside the reactors are highly toxic, presenting EC5048h < 1% for D. magna and EC5015min < 12% for A. fischeri. This result indicates that microcrustaceans are more sensitive to leachates, making them more suitable to our study. Pb showed the highest correlation with EC5048h, suggesting that Pb is the main chemical va...
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synthesis characterization and toxicological evaluation of cr2o3 nanoparticles using daphnia magna and Aliivibrio fischeri
Ecotoxicology and Environmental Safety, 2016Co-Authors: Rodrigo Costa Puerari, Silvia Pedroso Melegari, Cristina H. Da Costa, Cristiane Funghetto Fuzinatto, Denice Schulz Vicentini, Eder C Schmidt, Zenilda L Bouzon, William Gerson MatiasAbstract:Abstract Chromium III oxide (Cr2O3) nanoparticles (NPs) are used in pigments for ceramics, dyes, paints and cosmetics. However, few studies addressing the toxic potential of these NPs have been reported in the literature. Thus, this research aimed to evaluate the acute and chronic effects of Cr2O3 NPs through acute toxicity tests with Daphnia magna and Aliivibrio fischeri and chronic toxicity tests with Daphnia magna. Cr2O3 NPs were synthesized by the sol–gel method and characterized through TEM, X-Ray diffraction (XRD), zeta potential (ZP) and surface area analysis. In the acute toxicity tests the EC50,48h value obtained with D. magna was 6.79 mg L−1 and for A. fischeri the EC50,15min value was 16.10 mg L−1 and the EC50,30min value was 12.91 mg L−1. Regarding the chronic toxicity tests with D. magna, effects on longevity (OEC=1.00 mg L−1), reproduction (OEC=1.00 mg L−1) and growth (OEC=0.50 mg L−1) were observed. On the SEM and TEM images, ultrastructural alterations in the organelles of exposed organisms were also observed. Thus, toxicological studies with NPs are of great importance in order to reduce the risk of environmental contamination.