In this work a miniaturized and disposable electrochemical sensor was developed to evaluate the cadmium and lead ion phytoremediation potential by the floating aquatic macrophyte Lemna minor L. The ...sensor is based on a screen-printed electrode modified "in-situ" with bismuth film, which is more environmentally friendly than the mercury-based sensor usually adopted for lead and cadmium ion detection. The sensor was coupled with a portable potentiostat for the simultaneous measurement of cadmium and lead ions by stripping analysis. The optimized analytical system allows the simultaneous detection of both heavy metals at the ppb level (LOD equal to 0.3 and 2 ppb for lead and cadmium ions, respectively) with the advantage of using a miniaturized and cost-effective system. The sensor was then applied for the evaluation of or/and uptake by measuring the amount of the heavy metals both in growth medium and in plant tissues during 1 week experiments. In this way, the use of Lemna minor coupled with a portable electrochemical sensor allows the set up of a model system able both to remove the heavy metals and to measure "in-situ" the magnitude of heavy metal removal.
With the advent of technological advancements post the industrial revolution, thousands of chemicals are introduced into the market annually to enhance different facets of human life. Among these, ...pharmaceutical and personal care products (PPCPs), including antibiotics and disinfectants, such as benzalkonium chlorides (BACs), are prominent. BACs, often used for surface and hand disinfection in high concentrations or as preservatives in health products such as nasal sprays and eye drops, may present environmental risks if they seep into irrigation water through prolonged exposure or improper application. The primary objective of this study is to elucidate the tolerance mechanisms that may arise in Lemna minor plants, known for their remarkable capability to accumulate substances efficiently, in response to exogenously applied BACs at varying concentrations. The study applied six different concentrations of BACs, ranging from 0.25 to 10 mg L−1. The experimental period spanned seven days, during which the treatments were conducted in triplicate to ensure reliability and reproducibility of the results. It was observed that low concentrations of BACs (0.25, 0.5 and 1 mg L−1) did not elicit any statistically significant changes in growth parameters. However, higher concentrations of BACs (2.5, 5, and 10 mg L−1) resulted in a reduction in RGR by 20%, 28%, and 36%, respectively. Chlorophyll fluorescence declined significantly at BAC doses of 5 and 10 mg L−1, with Fv/Fm ratios decreasing by 9% and 15%, and Fv/Fo ratios by 40% and 39%, respectively. Proline content decreased in all treatment groups, with a 46% reduction at 10 mg L−1 BAC. TBARS and H2O2 contents increased proportionally with BAC dosage, showing the highest increases of 30% and 40% at 10 mg L−1, respectively. The noticeable increase in SOD enzyme activity at BAC concentrations of 0.5, 1, and 2.5 mg L−1, with increases of 2.7-fold, 2.2-fold, and 1.7-fold respectively, along with minimal accumulation of H2O2, suggests that L. minor plants have a strong tolerance to BAC. This is supported by the efficient functioning of the CAT and GST enzymes, especially evident at the same concentrations, where increased activities effectively reduce the buildup of H2O2. In the AsA-GSH cycle, although variations were observed between groups, the contribution of the GR enzyme to the preservation of GSH content by recycling GSSG likely maintained redox homeostasis in the plant, especially at low concentrations of BACs. The study revealed that L. minor effectively accumulates BAC alongside its tolerance mechanisms and high antioxidant activity. These results underscore the potential for environmental cleanup efforts through phytoremediation.
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•L. minor demonstrated elevated levels of H2O2 and TBARS after BAC exposure.•Growth parameters decreased at 2.5, 5 and 10 mg L−1 BAC.•Antioxidant activity increased under low-dose BAC applications.•L. minor exposed to low-dose BAC applications maintain the redox state.
Little is known about the effect of surface coatings on the fate and toxicity of CeO2 nanoparticles (NPs) to aquatic plants. In this study, we modified nCeO2 with chitosan (Cs) and alginate (Al) to ...obtain positively charged nCeO2@Cs and negatively charged nCeO2@Al, respectively, and exposed them to a representative aquatic plant, duckweed (Lemna minor L.). Uncoated nCeO2 could significantly inhibit the growth of duckweed, induce oxidative damage and lead to cell death, whereas nCeO2@Cs and nCeO2@Al exhibited lower toxicity to duckweed. ICP-MS analysis revealed that the Ce content in duckweed from the nCeO2 group was 1.74 and 2.85 times higher than that in the nCeO2@Cs and nCeO2@Al groups, respectively. Microscopic observations indicated that the positively charged nCeO2@Cs was more readily adsorbed on the root surface of duckweed than the negatively charged nCeO2@Al. The results of XANES and LCF demonstrated that a certain percentage of Ce(Ⅳ) was reduced to Ce(Ⅲ) after the interaction of the three NPs with duckweed, but the degree of biotransformation differed among the treatments. Specifically, the absolute contents of Ce(III) produced of nCeO2@Cs and nCeO2@Al through biotransformation were reduced by 55.5% and 83.5%, respectively, compared with that of the nCeO2 group, which might be the key factor for the diminished phytotoxicity of the coated nCeO2 to the duckweed. These findings were valuable for understanding the toxicity of metal-based NPs to aquatic plants and for the synthesis of environmentally friendly nanomaterials.
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•nCeO2 was separately modified with chitosan and alginate, called nCeO2@Cs nCeO2@Al.•Both nCeO2@Cs and nCeO2@Al were less toxic to duckweed than uncoated nCeO2.•The 2D distribution of Ce in roots was different under the three treatments.•Surface coating can alter the bioavailability and transformation of nCeO2.
This study developed a novel polymerase chain reaction (PCR) method, ligation-mediated self-formed panhandle PCR, for gene or chromosome walking. It combined the advantages of ligation-mediated PCR ...in its specificity and of panhandle PCR in its efficiency. Self-formed panhandle PCR was used for a new rbcS gene walking to isolate 3' downstream and 5' upstream sequence; 1292 bp DNA rbcS gene was obtained via 3' walking of Lemna minor gemonic DNA and 5' upstream sequence of the new rbcS gene with a length of 1543 bp was isolated from L. minor via self-formed panhandle PCR. A novel rbcS gene with the size of 2835 bp, which was confirmed by nested-PCR, was obtained by ligation-mediated self-formed panhandle PCR. Ligation-mediated self-formed panhandle PCR was simple and efficient and should have broad applications in the isolation of unknown sequences in genomes.
In this study the removal of arsenic by the Water Hyacinth (
Eichhornia crassipes) and Lesser Duckweed (
Lemna minor) was monitored under a concentration of 0.15
mg
L
−1 of the element. Plant ...densities were 1
kg/m
2 for Lesser Duckweed and 4
kg/m
2 for Water Hyacinth on a wet basis. The arsenic was determined in foliar tissue and water samples by hydride generation atomic absorption spectroscopy. The element was monitored as a function of time during 21 days. No significant differences were found in the bioaccumulation capability of both species. The removal rate for
L. minor was 140
mg As/ha
d with a removal recovery of 5%. The Water Hyacinth had a removal rate of 600
mg As/ha
d and a removal recovery of 18%, under the conditions of the assay. The removal efficiency of Water Hyacinth was higher due to the biomass production and the more favorable climatic conditions. This specie represents a reliable alternative for arsenic bioremediation in waters.
LEMNA MINOR L. AS A SOURCE OF ANTIOXIDANTS Petrova-Tacheva, V.; Ivanov, V.; Atanasov, A.
Trakia journal of sciences,
12/2020, Letnik:
18, Številka:
Suppl.1
Journal Article
Recenzirano
Odprti dostop
Lemna Minor L. (LM) is a perennial aquatic plant that belongs to the genus Lemna, the family Lemnaceae and is spread almost ubiquitously. In folk medicine, it is used in the treatment of allergies, ...asthma, vitiligo, jaundice, glaucoma, rheumatism, gout, and others. In recent years it has become clear that its chemical composition consists of: proteins (up to 35%), vegetable fibers (up to 17%), fats (up to 5%), polysaccharides, flavonoids, amino acids, aliphatic acids, phenolic acids, triterpene compounds, vitamins, micro- and macro-elements and other substances. А significant part of these substances exhibit the antioxidant activity. The scientific information for 12 biologically active substances with antioxidant activity isolated from Lemna Minor is presented in the review.
The aim was to assess the ability of microcosms (laboratory-scale shallow ponds) as a post polishing stage for the remediation of artificial textile wastewater comprising two commercial dyes (basic ...red 46 (BR46) and reactive blue 198 (RB198)) as a mixture. The objectives were to evaluate the impact of
Lemna minor
L. (common duckweed) on the water quality outflows; the elimination of dye mixtures, organic matter, and nutrients; and the impact of synthetic textile wastewater comprising dye mixtures on the
L
.
minor
plant growth. Three mixtures were prepared providing a total dye concentration of 10 mg/l. Findings showed that the planted simulated ponds possess a significant (
p
< 0.05) potential for improving the outflow characteristics and eliminate dyes, ammonium-nitrogen (NH
4
-N), and nitrate-nitrogen (NO
3
-N) in all mixtures compared with the corresponding unplanted ponds. The removal of mixed dyes in planted ponds was mainly due to phyto-transformation and adsorption of BR46 with complete aromatic amine mineralisation. For ponds containing 2 mg/l of RB198 and 8 mg/l of BR46, removals were around 53%, which was significantly higher than those for other mixtures: 5 mg/l of RB198 and 5 mg/l of BR46 and 8 mg/l of RB198 and 2 mg/l of BR46 achieved only 41 and 26% removals, respectively. Dye mixtures stopped the growth of
L
.
minor
, and the presence of artificial wastewater reduced their development.
This study was designed to investigate removal efficiencies of Cu, Pb, Zn, and As in gallery water in a mining area in Keban, Turkey by Lemna gibba L. and Lemna minor L. These plants were placed in ...the gallery water of Keban Pb–Zn ore deposits and adapted individually fed to the reactors. During the study period (8 days), the plant and water samples were collected daily and the temperature, pH, and electric conductivity of the gallery water were measured daily. The plants were washed, dried, and burned at 300 °C for 24 h in a drying oven. These ash and water samples were analyzed by ICP-MS to determine the amounts of Cu, Pb, Zn, and As. The Cu, Pb, Zn and As concentrations in the gallery water of the study area detected 67, 7.5, 7230, and 96 μg L−1, respectively. According to the results, the obtained efficiencies in L. minor L. and L. gibba L. are: 87% at day 2 and 36% at day 3 for Cu; 1259% at day 2 and 1015% at day 2 for Pb; 628% at day 3 and 382% at day 3 for Zn; and 7070% at day 3 and 19,709% at day 2 for As, respectively. The present study revealed that both L. minor L. and L. gibba L. had very high potential to remove Cu, Pb, Zn, and As in gallery water contaminated by different ores.
•We investigated Cu, Pb, Zn and As accumulations in gallery water using aquatic plants.•We calculated the phytoremediation potential of L. gibba L. and L. minor L..•These plants showed very high performances to accumulate Cu, Pb, Zn and As.•It was detected the optimal harvesting time of these plants for Cu, Pb, Zn and As.
The objective of this study was to investigate the impact of two pharmaceuticals, diclofenac and sulfamethoxazole, and their binary mixture on aquatic organisms, marine bacteria Aliivibrio fischeri, ...crustacean Daphnia magna, and vascular plant Lemna minor. The binary mixture of the drugs showed the highest toxicity towards the model organisms. Diclofenac had an average toxicity which posed a high environmental risk to aquatic organisms, while sulfamethoxazole was characterized by a low toxicity with low environmental risk. The organism most sensitive to diclofenac was A. fischeri (IC50 = 8.72 ± 1.14 mg L−1) and for sulfamethoxazole and the binary mixture, it was L. minor (IC50 = 12.56 ± 4.48 and 4.83 ± 0.43 mg L−1, respectively). The toxicity of the mixture was predicted using the Concentration Addition and Independent Action models, and the results were compared with the experimental data. None of the models suitably predicted the real toxicity of the pharmaceutical mixture. Interactions between the mixture components were confirmed by calculating the mixture toxicity index values which showed that the pharmaceuticals displayed synergistic or partial additive effects which depended on the selected test organism and test duration. When added as a complex matrix to wastewater (at a concentration of 2 mg L−1 each), the pharmaceuticals did not display increased toxicity. This observation confirms that the presence of micro-contaminants in aquatic environments may cause interactions between different compounds, the results of which are difficult to predict and model.
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•Synergistic or partial additive effects of DCF and SMX mixture were observed.•DCF posed an average toxicity and high environmental risk.•SMX is a low-toxicity compound with a low environmental risk.•The CA and IA models did not suitably predict the toxicity of the mixture.
Among the most used non-steroidal anti-inflammatory drugs (NSAIDs), ketoprofen (KTF) assumes an important position. Nevertheless, its ecotoxicological effects in non-target organisms are poorly ...characterized, despite its use and frequency of occurrence in aquatic matrices. Thus, the aim of this study was to evaluate the possible toxicological effects of KTF contamination, in two freshwater species, Lemna minor and Daphnia magna, by measuring biochemical, physiological and population parameters. To attain this objective, both species were exposed to KTF at the same concentrations (0, 0.24, 1.2, 6 and 30 μg/L). L. minor plants were exposed during 4 d to these levels of KTF, and the enzymatic activity (catalase (CAT), glutathione S-transferases (GSTs) and carbonic anhydrase (CA)), and pigments content (chlorophylls a, b and total and carotenoids) were analyzed to evaluate the toxicity of this drug. D. magna was acutely and chronically exposed to KTF, and enzymatic activities (CAT, GSTs and cyclooxygenase (COX)), the feeding rates, and reproduction traits were assessed. In L.minor, KTF provoked alterations in all enzyme activities, however, it was not capable of causing any alteration in any pigment levels. On the other hand, KTF also provoked alterations in all enzymatic activities in D. magna, but did not affect feeding rates and life-history parameters. In conclusion, exposure to KTF, provoked biochemical alterations in both species. However, these alterations were not reflected into deleterious effects on physiological and populational traits of L. minor and D. magna.
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•Ketoprofen (KTF) acts different on Lemna minor and on Daphnia magna.•Effects of KTF were limited only to biochemical effects on both species.•L. minor effects of low KTF concentrations suggest resilience and hormetic effects.•D. magna, in general, presented a dose response pattern to KTF exposure.
KTF demonstrates species-specific toxicity to different aquatic organisms affecting biochemical levels but not impairing physiological and population levels.
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