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1.
Sci Total Environ ; 730: 139142, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32416508

RESUMO

Sludge treatment wetlands (STWs) are widely used to treat surplus sludge in recent years. However, the effects of plant species and loading rates on sludge characteristics in earthworm assistant STWs remain unclear. In the current study, six STWs planted with two plant species (Phragmites australis, Typha angustifolia) were investigated under four loading rates (60, 80, 90 and 120 kg DS/m2/yr) regarding the influence on sludge characteristics. Furthermore, earthworms were added in three STWs to evaluate their role on sludge stabilization during resting period. Results showed that the best sludge dewatering (dry solids (DS) of 45.0%) and stabilization (volatile solids to total solids (VS/TS) of 40.5%) were determined in the P. australis STWs at the loading rate of 80 kg DS/m2/yr. Furthermore, VS/TS and Escherichia coli contents in earthworm STWs were 5.5-11.2% and 12-39% lower than that in the control without earthworm addition. Meanwhile, earthworm also decreased the nutrient contents in STWs. However, earthworms had insignificant effects on heavy metal contents in STWs. Nevertheless, the bioavailability of Cd and Cr in STWs were decreased by earthworm addition, with an acid-soluble fraction of Cd and Cr reduced by 11.2-18% and 2.5-7.5%, respectively. In conclusion, sludge characteristics can be improved by earthworm addition in P. australis STWs.


Assuntos
Oligoquetos , Esgotos , Animais , Poaceae , Typhaceae , Áreas Alagadas
2.
Int J Syst Evol Microbiol ; 70(3): 2003-2007, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32234114

RESUMO

A yellow-pigmented, Gram-stain-negative, aerobic, non-motile rod shaped, mesophilic bacterium, designated strain N7XX-4T, was isolated from cattail root grown on the mine tailings of Phoenix mountain, Tongling city, Anhui Province (PR China). Analysis of the 16S rRNA gene sequence revealed that the strain represented a novel member of the family Microbacteriaceae. The nearest phylogenetic neighbour was Lysinimonas kribbensis MSL-13T (97.8 % 16S rRNA gene sequence similarity). The most abundant fatty acid in whole cells of N7XX-4T was anteiso-C15 : 0 (29.9 %). The predominant menaquinones were MK-12(H2), MK-13(H2) and MK-11(H2). The peptidoglycan type of the isolate was B1δ with l-Lys as the diagnostic cell-wall diamino acid. On the basis of differences in phenotypic and genotypic characteristics, strain N7XX-4T (=CGMCC 1.16548T=DSM 106791T=JCM 32630T) is designated as the type strain of a novel species of the genus Lysinimonas, for which the name Lysinimonas yzui sp. nov. is proposed.


Assuntos
Actinobacteria/classificação , Mineração , Filogenia , Microbiologia do Solo , Typhaceae/microbiologia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Peptidoglicano/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
3.
Chemosphere ; 253: 126681, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278919

RESUMO

Rhizobacterial dynamics, relating to pollutant degradation mechanisms, over the course of plant lifespan have rarely been reported when using phytoremediation technologies for pharmaceutical-contaminated wastewater treatment. This study investigated the rhizobacterial dynamics of Typha angustifolia in constructed wetlands to treat ibuprofen (IBP)-polluted wastewater throughout plant development from seedling, vegetative, bolting, mature, to senescent stages. It was found that conventional pollutant and IBP removals increased with plant development, reaching to the best performance at bolting or mature stage (removal efficiencies: 92% organics, 52% ammonia, 60% phosphorus and 76% IBP). In the IBP-stressed wetlands, the rhizobacterial diversity during plant development was adversely affected by IBP accompanied with a reduced evenness. The bacterial communities changed dynamically at different developmental stages and showed significant differences compared to the control wetlands (free of IBP). The dominant bacteria colonized in the rhizosphere was the phylum Actinobacteria, having a final relative abundance of 0.79 and containing a large amount of genus norank_o__PeM15. Positive interactions were evident among the rhizobacteria in IBP-stressed wetlands and the predicted functions of 16S rRNA genes revealed the potential co-metabolism and metabolism of IBP. The co-metabolism of IBP might be related to root exudates such as amino acid, lipid, fatty acid and organic acid. In addition, positive correlations between the organic compounds of interstitial water (bulk environment) and the rhizobacterial communities were observed in IBP-stressed wetlands, which suggests that the influence of IBP on bulk microbiome might be able to modulate rhizosphere microbiome to achieve the degradation of IBP via co-metabolism or metabolism.


Assuntos
Biodegradação Ambiental , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Animais , Bactérias/genética , Ibuprofeno , Estágios do Ciclo de Vida , Microbiota , Preparações Farmacêuticas , Desenvolvimento Vegetal , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Rizosfera , Microbiologia do Solo , Typhaceae/microbiologia , Águas Residuárias , Poluentes Químicos da Água/análise
4.
Chemosphere ; 251: 126377, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32143081

RESUMO

Eight constructed wetland microcosm (CWM) units have been designed using three macrophytes for domestic wastewater treatment. The main aim of this study is to evaluate enzyme activities with respect to time and soil depth and their correlation with removal efficiency of pollutants within different CWM units. The findings of this study show that the activity of enzymes and pollutants removal efficiency vary to a great extent on the soil depth, time of the sampling and type of pollutants. The correlation between removal of soluble reactive phosphorus and total phosphorus was significant with phosphatase activity in most of the CWM units. Activity of urease and NH4+-N removal was positively correlated with significant positive correlation in CWM units planted with Phragmites karka, and Pistia stratiotes (Ph + Pi) and Typha latifolia, Phragmites karka and Pistia stratiotes (T + Ph + Pi). Urease activity was found to be both positively and negatively correlated with respect to removal of NO3--N and NO2--N in different CWM units. Dehydrogenase activity showed negative correlation with respect to biological oxygen demand (BOD) removal except in CWM units with Ph + Pi and T + Ph + Pi. Similarly, a moderate positive and negative correlation exists between fluorescein diacetate hydrolysis and BOD removal. Removal of BOD and microbial biomass carbon (MBC) was negatively correlated with each other in most of the CWM units. With respect to vertical variation, the top layer of CWM units expressed significantly higher activity of extracellular enzymes and were significantly different from the deeper layer. CWM units exhibited significant variations in enzyme activity with respect to time.


Assuntos
Enzimas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Análise da Demanda Biológica de Oxigênio , Biomassa , Carbono , Nitrogênio/análise , Fósforo/análise , Poaceae , Solo , Typhaceae , Águas Residuárias
5.
Int J Phytoremediation ; 22(8): 863-871, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32028785

RESUMO

The potential of Iris pseudacorus and Typha domingensis to remove the pharmaceutical active compound (PhAC) Furosemide from a nutrient solution was assessed. Both plants were exposed to 2 mg L-1 of furosemide during 21 days and the removal of furosemide was monitored. Vessels without furosemide were also implemented as control systems for plants development. Likewise, unplanted vessels with furosemide were employed to assess abiotic removal mechanisms. All vessels were covered with aluminum foil to avoid photodegradation of the compound. Both plants showed potential to remove Furosemide, attaining, at the end of the experiment, a removal of 42.0-66.9% and 40.5-57.8%, for Typha and Iris, respectively. The plants do not presented a visible negative stress response to the exposure to furosemide, having a positive growth rate at the end of the experiment. Biodegradation seems to play an important role in furosemide removal, being enhanced by the presence of the plants. The two macrophytes presented different removal behaviors, particularly in the first 48 h of contact time. FUR removal by Iris follows a pseudo-first order while by Typha is divide in different phases. These results indicate that different plants species seem to have different mechanisms to remove pollutants from water.HighlightsPhACs removal potential of Iris pseudacorus and Typha domingensis was assessed.Plants were exposed to 2 mg L-1 of furosemide during 21 days.Both macrophytes showed good removal efficiencies.Biodegradation of furosemide seems to be the main removal mechanism.Plants demonstrated different removal behavior along the experiment.Removal mechanisms of plants seem to differ between species.


Assuntos
Typhaceae , Poluentes Químicos da Água , Biodegradação Ambiental , Furosemida , Hidroponia , Áreas Alagadas
6.
Sci Total Environ ; 714: 136741, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32018963

RESUMO

Selenium (Se) is essential to most animals, whereas the gap between necessity and toxicity is narrow. Our previous work showed constructed wetlands were a promising solution to Se contamination in aquatic habitats. This study further examined effects of organic amendments and hydrologic regimes on Se removal by constructed wetlands. Our results suggest the removal efficiency exceeded 94% within 8 days for the systems with moderate and low organic carbon contents in the substrate, as a 98% removal of Se was obtained in three weeks for the system subjected to the 2-day wet/dry cycle. To mimic field wetlands, a litter layer was added to the cattail treatment system, which reduced waterborne Se much more rapidly than control, achieving a 77% removal of Se within 4 days. XAS results show all sediment Se was transformed to Se0 in the presence of litter, as SeMet (47%) dominated the Se adsorbed by the litter. The findings indicate the Se removal capacity of a constructed wetland would improve over time, especially via Se volatilization into the atmosphere and Se stabilization in the sediment with litter accumulating at the surface. Another mesocosm experiment showed the cattail floating system effectively removed Se, particularly selenate, by 99% in 48 h. To confirm that high performance, seven constructed wetland types were set up for comparison. The results show the cattail floating system was most effective in Se removal (93-100% at around 35 °C in summer and 51-100% at about 5 °C in winter). More research is needed to test the floating system under more field conditions and investigate the biomagnification and biotransformation of the removed Se along food chains. Seven constructed wetland types were set up for comparison.


Assuntos
Purificação da Água , Selênio , Typhaceae , Áreas Alagadas
7.
Int J Phytoremediation ; 22(7): 679-686, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32107924

RESUMO

Effect of polyculture of woody and herbaceous plant with different ecological niche in constructed wetlands (CWs) on wastewater treatment is unclear. Herein, three kinds of polyculture CWs were constructed to treat domestic wastewater: woody polyculture system (W, Nerium and Hibiscus), herbaceous polyculture system (H, Acorus and Typha), woody and herbaceous polyculture system (WH, Nerium, Hibiscus, Acorus and Typha) and non-planted system (N) as control. The seasonality removal performance of pollutant, activities of urease and phosphatase, microscopic characteristics of roots were measured. Results showed that the average removals of COD, TN and TP in WH were significantly higher than that in the other systems. Interspecies competition existed in WH system, while the difference in terms of biomass gradually diminished. Furthermore, the root lengths, area, volume and tip number were higher compared to the other systems. The correlation between the removal rate of TP and activity of phosphatase in upper and bottom layer of CWs showed the opposite tendency, the distribution of plant roots in polyculture essentially impact TP removal rate in CWs. Our results provide the necessary insights for appropriately selecting different plant types for doing polyculture in CWs.


Assuntos
Typhaceae , Águas Residuárias , Biodegradação Ambiental , Nitrogênio , Eliminação de Resíduos Líquidos , Áreas Alagadas
8.
Bull Environ Contam Toxicol ; 104(3): 358-365, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31975014

RESUMO

Variations of phytoaccumulation and tolerance in different growth stages of plant are important factors for effective removal of pollutants in phytoremediation. The present work investigated arsenic (As) accumulation, As-tolerance and the physiological tolerance mechanisms of Typha angustifolia under different As-level during the seedling, fast-growing and breeding stages. The results showed that As mainly distributed in the underground part and total As accumulation increased with growth stages. Maximum growth rates under lower As occurred in seedling stage, whereas occurred in breeding stage under higher As. T. angustifolia exhibited the highest tolerance ability under 150 mg kg-1 As and tolerance index (TI) varied from seedling to breeding stages. During seedling stage, TI was affected by plant height (Hshoot) and net photosynthesis, which control biomass production. During fast-growing stage, Hshoot and root glutathione (GSH) co-regulated plant As-tolerance. During breeding stage, physiological metabolic processes, especially GSH-mediated processes, played a critical role in improving plant As-tolerance.


Assuntos
Aclimatação , Arsênico/análise , Typhaceae/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Biomassa , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Typhaceae/metabolismo
9.
Sci Total Environ ; 714: 136603, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31982738

RESUMO

The ability of the native emergent macrophytes Typha domingensis for monitoring pollution with trace metals in Egyptian Lake Burullus was investigated through developing regression models for predicting their concentrations in the plant tissues. Plant samples (above-ground shoot and below-ground root and rhizome) as well as sediment samples were collected monthly during one growing season and analyzed. The association of trace metals concentration with several sediment characteristics (pH, organic matter, clay and silt) was also studied using the simple linear correlation coefficient (r). The concentration of some trace metals was significantly proportional to its values in the sediment such as Cd in the shoot, rhizome and root, Fe in the rhizome, and Ag in the root. There was positive relationship between the bioaccumulation factor (BAF) of Ag, Cd, Fe, Pb and Zn and sediment pH, organic matter and clay content. The developed regression models were significantly valid with high model efficiency and coefficient of determination, and low mean normalized average error. Trace metals were accumulated in the below-ground root and rhizome rather than in the shoot. Only Ag, Co and Ni provided bioaccumulation factor (BAF) < 1, while Ag was the only trace metal that could be transferred to some extend from the root to the rhizome and from there to the shoot [translocation factor (TF) 2.55 and 1.15, respectively]. Typha domingensis in Lake Burullus could be regarded as a bioindicator of trace metals pollution, and a good candidate as phytoremediator for Ag. The information on the phytoremediation capacity of T. domingensis certainly helps to solve contamination problems at Egyptian Lake Burullus region using this native plant.


Assuntos
Typhaceae , Monitoramento Biológico , Egito , Lagos , Metais Pesados , Poluentes Químicos da Água
10.
Nat Prod Res ; 34(7): 1041-1045, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30580603

RESUMO

The pollen of T. angustifolia, also known as Pu huang in Chinese, has been used for treatment of stranguria, hematuria, dysmenorrhea, metrorrhagia and injuries in China for a long time. Extensive efforts have been directed toward its phytochemical and biological aspects. However, little is known about its anti-nociceptive implication and material basis. This work presented the investigation of the anti-nociceptive effect of Typhae Pollen using an effect-directed fractionation strategy, thereby leading to identification of isorhamnetin-3-O-neohesperidin (1) and typhaneoside (2), together with other minor flavonoid glycoside congeners, as the main anti-nociceptive constituents. This work not only unveils the anti-nociceptive potential of Typhae Pollen, but also establishes a method to enrich and identify the anti-nociceptive constitutes of Typhae Pollen. Moreover, this work is a successful example of effect-directed fractionation strategy, which represents a powerful tool in TCM-based drug discovery and development.


Assuntos
Analgésicos/isolamento & purificação , Flavonoides/farmacologia , Pólen/química , Typhaceae/química , Analgésicos/química , Animais , Fracionamento Químico/métodos , China , Medicamentos de Ervas Chinesas , Flavonoides/química , Flavonoides/isolamento & purificação , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia
11.
Chemosphere ; 241: 125018, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31683415

RESUMO

Animal production is a source of heavy metals in livestock wastewater and also a key link in the food chain, with negative impacts on human and animal health. In intensive animal production systems, the most critical elements are zinc and copper. In order to development of innovative non-invasive strategies to reduce the environmental impact of livestock, this study assessed the ability of two plants, Typha latifolia and Thelypteris palustris, to bioaccumulate the heavy metals used in animal nutrition, from wastewater. Four mesocosms (width 2.0 m, length 2.0 m, 695 L of water, 210 kg of soil) were assembled outdoors at the Botanical Garden. Two of them were planted with T. latifolia (TL treated, n = 30; TL control, n = 30) and two with T. palustris (TP treated, n = 60; TP control, n = 60). In T0 a solution of a mineral additive premix (Zn 44.02 mg/L; Cu 8.63 mg/L) was dissolved in the treated mesocosms. At T0, d 15 (T1) and d 45 (T2) samples of roots, leaves, stems, soil and water were collected, dried, mineralized and analyzed using ICP-MS in order to obtain HMs content. We found that T. latifolia and T. palustris accumulate and translocate Zn, Cu from contaminated wastewater into plant tissues in a way that is directly related to the exposure time (T2 for Zn: 271.64 ±â€¯17.70, 409.26 ±â€¯17.70 for Cu: 47.54 ±â€¯3.56, 105.58 ±â€¯3.56 mg/kg of DM, respectively). No visual toxicity signs were observed during the experimental period. This phytoremediation approach could be used as an eco-sustainable approach to counteract the output of heavy metals.


Assuntos
Bioacumulação , Biodegradação Ambiental , Metais Pesados/farmacocinética , Typhaceae/metabolismo , Águas Residuárias/química , Animais , Cobre/farmacocinética , Gado , Metais Pesados/análise , Folhas de Planta/química , Raízes de Plantas/química , Traqueófitas/crescimento & desenvolvimento , Traqueófitas/metabolismo , Typhaceae/crescimento & desenvolvimento , Zinco/análise , Zinco/farmacocinética
12.
Artigo em Inglês | MEDLINE | ID: mdl-31653194

RESUMO

Thermophilic anaerobic digestion (AD) of cattail followed by hydrothermal carbonization (HTC) was studied. The intent of the research was to develop agricultural waste-based biorefining technologies for bioenergy production along with value-added products. Cattail was anaerobically digested at 55 °C for 14 days and protein and cellulose components were partially degraded. The average methane yield was 230-280 mL/g volatile solids and the total solids decreased by 33-55%. When the particle size of cattail was reduced from 1 in. to 1 mm, the lag phase was shortened from 1.48 to 0 d. Following the AD process of cattail, the AD digestate was hydrothermally carbonized at 250 °C for 4 h, yielding approximately 6.7-7.5 wt % gaseous products, 64 wt % liquid products and 28 wt % hydrochar. The gaseous products contained >5000 ppm H2S and liquid products possessed fewer chemicals and higher ratio of phenolic compounds compared to the liquid products from HTC of original cattail. The hydrochar had a higher carbon content (76.8-79.8%) and a higher specific surface area (∼10 m2/g) than those of the feedstock. Hydrochar was further activated by using Na2CO3, NaHCO3 and NaCl. The activation process increased the carbon content and specific surface area to 84-93% and 250-630 m2/g, respectively.


Assuntos
Biocombustíveis/análise , Carvão Vegetal/química , Metano/biossíntese , Typhaceae/metabolismo , Anaerobiose , Celulose/metabolismo , Gases/análise , Proteínas de Plantas/metabolismo , Temperatura
13.
Int J Phytoremediation ; 22(2): 157-166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31402676

RESUMO

The main purpose of this study was to investigate the removal of ammonia, orthophosphate, and COD present in landfill leachate using vertical subsurface flow constructed wetland systems (VFCW). The effect of different types of plants (Typha latifolia and Canna indica) in the removal of pollutants was also investigated. The systems were operated identically at a flow rate of 5 l/day and a hydraulic retention time (HRT) of 22 days in the T. latifolia reactor (R1), C. indica reactor (R2), and Control reactor (R3). Concentration-based average removal efficiencies for R1, R2, and R3 were NH4-N; 60.0%, 56.0%, and 46, COD; 81.0%, 84.0%, and 79.0%, PO4-P; 45.0%, 46.0%, and 32.0%, respectively. These results show that the model is a good predictive tool for determining the plant lengths using the growth equations. It is also revealed that the Logistic and Cubic models are suitable for the R1 and R2 reactors.


Assuntos
Typhaceae , Poluentes Químicos da Água , Biodegradação Ambiental , Nitrogênio , Eliminação de Resíduos Líquidos , Áreas Alagadas
14.
Int J Phytoremediation ; 22(3): 295-304, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31475577

RESUMO

Plant species selection is an important criterion for improving treatment wetland performance. The aim of this work was to evaluate removal efficiency and potential uses of woody species in treatment wetlands during the establishment year. Plant development, removal efficiency and evapotranspiration rate of five woody species (Salix interior, Salix miyabeana, Sambucus canadensis, Myrica gale, Acer saccharinum) and four herbaceous taxa typically used in treatment wetlands (Typha angustifolia, Phragmites australis australis, Phragmites australis americanus, Phalaris arundinacea) were compared in a mesocosm-scale study during one growing season. Woody species showed significantly slower growth, but displayed several characteristics of interest for treatment wetland applications: good adaptation to wetlands conditions; high organic matter removal (76-88%); high nutrient accumulation in tissues and high evapotranspiration capacity. During the establishment year, herbaceous species showed greater biomass development (above- and belowground parts), higher evapotranspiration rate (>3.84 L m-2 d-1 compared to <3.23 L m-2 d-1 for woody species) and overall pollutant removal efficiency. These characteristics confirm the high efficiency of treatment wetlands planted with herbaceous species even in the first growing season. However, given their greater potential biomass development, woody species could represent an excellent alternative for improving treatment wetlands long-term performance.


Assuntos
Typhaceae , Áreas Alagadas , Biodegradação Ambiental , Poaceae , Eliminação de Resíduos Líquidos
15.
Chemosphere ; 243: 125353, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31765899

RESUMO

Here we compared the performance of four macrophytes namely Brachia mutica, Typha domingensis, Phragmites australis and Leptochala fusca, in bacterially assisted floating treatment wetlands (FTWs) for the clean-up of five trace metals (Fe, Mn, Ni, Pb, and Cr) from polluted river water. The river water was artificially spiked with reagent grade chemicals to increase the trace metal pollution. The macrophytes were planted in a polystyrene sheet to prepare FTWs, which were placed over the metal-contaminated river water. The consortium of five rhizospheric and endophytic bacterial strains, i.e., Aeromonas salmonicida, Pseudomonas indoloxydans, Bacillus cerus, Pseudomonas gessardii, and Rhodococcus sp., was inoculated support the natural remediation ability. We found a significant reduction in the metal content by all four macrophytes and the removal was significantly enhanced when bacterial inoculum was applied. The maximum removal was observed in FTWs planted with P. australis and inoculated with bacteria. In this treatment (T6) the Fe, Mn, Ni, Pb and Cr contents were reduced to 0.53, 0.20, 0.09, 1.04 and 0.07 mg L-1 after five weeks retention time. The bacterial inoculation sufficiently increased the plant biomass. All macrophytes depicted potential to uptake and translocate trace metals in the roots instead of shoots. The bacterial inoculation acclimatize the plants roots followed by shoots and enhanced the uptake of metals by macrophytes. This study emphasized the usefulness of macrophytes-bacteria mutualism in FTWs system for the remediation of trace metals. The similar systems may provide practical solutions for the remediation of trace metals of polluted river water.


Assuntos
Biodegradação Ambiental , Metais Pesados/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Áreas Alagadas , Bactérias , Biomassa , Chumbo , Poaceae/microbiologia , Rios , Oligoelementos/análise , Typhaceae , Poluição da Água
16.
Ecotoxicol Environ Saf ; 189: 109959, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31787383

RESUMO

The Phytotoxicity of and mechanism underlying selenite-mediated tolerance to Cd stress in Typha angustifolia were studied hydroponically with respect to metal uptake and translocation, photosynthesis-related parameters, contents of proline and O2•-, products of lipid peroxidation, cell viability, enzymatic and non-enzymatic antioxidants, glyoxalases and phytochelatins. T. angustifolia were exposed to 25, 50 and 100 µM of Cd alone and in conjunction with 5 mg L-1 of selenite in full-strength Hoagland's nutrient solution for 30 days. Results showed that Cd contents in T. angustifolia leaves and roots increased in a dose-dependent manner and were higher in roots, but those of BAC, BCF and TF changed in a contrary pattern. Addition of selenite to Cd-containing treatments further reduced Cd levels in T. angustifolia leaves and roots, as well as BAC, BCF and TF. A diphasic effect was found in T. angustifolia for the contents of total chlorophyll, GSH, PC and GSSG, as well as activities of CAT, POD, SOD and GR, in response to Cd stress alone and in conjunction with selenite supplementation, but the same effect was not observed for Pn, Cond, Tr, Ci, Fv/Fm and ϕPSII. In contrast, exogenous selenite supplementation enhanced the contents of total chlorophyll and the non-enzymatic antioxidants, as well as activities of enzymatic antioxidants, while the values of photosynthetic fluorescence parameters were rescued. Selenite addition decreased Cd-induced cell death. Proline contents and Gly I activities in T. angustifolia leaves kept increasing in a dose-dependent manner of Cd concentrations in the growth media and selenite addition further enhanced both parameters. Addition of selenite could quench Cd-mediated generation of MDA, O2•- and MG in T. angustifolia leaves and reduce Cd-induced Gly II activity. A U-shaped GSH/GSSG ratio in T. angustifolia leaves suggests a possible trade-off between PC synthesis and GR activity since both share the same substrate GSH. Therefore, confined BAC, BCF and TF were a mechanism that confers T. angustifolia tolerance to Cd stress, and that exogenous selenite supplementation could depress Cd-induced stress in T. angustifolia by rescuing the photosynthetic fluorescence, enhancing non-enzymatic and enzymatic antioxidants that scavenge O2•- and MG, and potentiating PC synthesis that chelates Cd.


Assuntos
Cádmio/toxicidade , Ácido Selenioso/farmacologia , Typhaceae/efeitos dos fármacos , Antioxidantes/metabolismo , Cádmio/metabolismo , Clorofila/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fitoquelatinas/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Prolina/metabolismo , Typhaceae/metabolismo
17.
Environ Technol ; 41(9): 1101-1106, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30198835

RESUMO

In this study, cattail (Typha latifolia) was used to remove Na+ and Cl- from polluted soil (PS) in a solid waste open dumping site. Hydroponic system was also evaluated to remove Na+ and Cl- from landfill leachate. The results indicated that the cattail grown in PS had higher biomass yield of 44.4 ± 3.29 g compared to that of control (35.3 ± 4.28 g). Nitrogen and phosphorous contents of cattails grown in PS were also higher than that of control plants, and the electrical conductivity of PS significantly decreased from 245 ± 1.40 to 51.9 ± 9.30 ms/m over the 5-week experimental duration. Na+ and Cl- contents from cattail grown on PS were 10.8 ± 1.85 and 64.7 ± 9.15 g/kg biomass, respectively. For cattails grown hydroponically in water containing leachate, nitrogen and phosphorous accumulation was 51.1 ± 5.94 and 9.32 ± 3.22 g/kg biomass, respectively. The corresponding biomass yield of these cattails was 13.5 ± 1.29 g at the end of 5 weeks. In addition, the Na+ and Cl- accumulation of 55.5 ± 4.82 and 78.2 ± 28.3 g/Kg biomass, respectively, was higher in hydroponic cattails grown in this study. Overall, the results suggest the effectiveness of cattails for phytoremediation of contaminated soil and the high efficiency of hydroponic system for nutrient and salinity removal compared to the conventional soil test.


Assuntos
Typhaceae , Poluentes Químicos da Água , Biodegradação Ambiental , Solo , Instalações de Eliminação de Resíduos
18.
Environ Sci Pollut Res Int ; 27(5): 4905-4916, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31845259

RESUMO

The effects of Typha latifolia L. on the remediation of cadmium (Cd) in wetland soil were studied using greenhouse pot culture, with soil Cd concentrations of 0, 1, and 30 mg/kg. The T. latifolia showed excellent tolerance to the low and high concentrations of Cd in soil. A higher bioaccumulation of Cd was observed in roots, with bioconcentration factor values of 51.6 and 9.30 at 1 and 30 mg/kg of Cd stress, respectively; Cd concentration in T. latifolia was 77.0 and 410.7 mg/kg, and Cd content was 0.11 and 0.22 mg/plant at the end of the test period. The soil enzyme activities (urease, alkaline phosphatase, and dehydrogenase) exposed to 0, 1, and 30 mg/kg Cd were measured after 0-, 30-, 60-, and 90-day cultivation period and showed an increasing trend with exposure time. Metabolite changes were analyzed using liquid chromatography-mass spectrometry, combined with principal component analysis and orthogonal partial least squares discrimination analysis. Among 102 metabolites, 21 compounds were found and identified, in response to treatment of T. latifolia with different Cd concentrations. The results showed that T. latifolia had a good remedial effect on Cd-contaminated soil. The metabolites of T. latifolia changed with different Cd concentration exposures, as a result of metabolic response of plants to Cd-contaminated soils. Analysis of metabolites could better reveal the pollution remediation mechanism involved in different Cd uptake and accumulate properties.


Assuntos
Poluentes do Solo , Typhaceae , Biodegradação Ambiental , Cádmio , Raízes de Plantas , Solo , Poluentes do Solo/análise , Poluentes do Solo/química , Typhaceae/química , Áreas Alagadas
19.
Chemosphere ; 240: 124915, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563105

RESUMO

In animal livestock heavy metals are widely used as feed additives to control enteric bacterial infections as well as to enhance the integrity of the immune system. As these metals are only partially adsorbed by animals, the content of heavy metals in manure and wastewaters causes soil and ground water contamination, with Zn2+ and Cu2+ being the most critical output from pig livestock. Phytoremediation is considered a valid strategy to improve the purity of wastewaters. This work studied the effect of Zn2+ and Cu2+ on the morphology and protein expression in Thelypteris palustris and Typha latifolia plants, cultured in a wetland pilot system. Despite the absence of macroscopic alterations, remodeling of cell walls and changes in carbohydrate metabolism were observed in the rhizomes of both plants and in leaves of Thelypteris palustris. However, similar modifications seemed to be determined by the alterations of different mechanisms in these plants. These data also suggested that marsh ferns are more sensitive to metals than monocots. Whereas toleration mechanisms seemed to be activated in Typha latifolia, in Thelypteris palustris the observed modifications appeared as slight toxic effects due to metal exposure. This study clearly indicates that both plants could be successfully employed in in situ phytoremediation systems, to remove Cu2+ and Zn2+ at concentrations that are ten times higher than the legal limits, without affecting plant growth.


Assuntos
Biodegradação Ambiental/efeitos dos fármacos , Cobre/toxicidade , Traqueófitas/metabolismo , Typhaceae/metabolismo , Eliminação de Resíduos Líquidos/métodos , Zinco/toxicidade , Animais , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Cobre/farmacocinética , Gado , Esterco , Projetos Piloto , Células Vegetais/efeitos dos fármacos , Células Vegetais/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas , Especificidade da Espécie , Suínos , Traqueófitas/efeitos dos fármacos , Typhaceae/efeitos dos fármacos , Águas Residuárias/química , Águas Residuárias/toxicidade , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/toxicidade , Áreas Alagadas , Zinco/farmacocinética
20.
Int J Phytoremediation ; 22(6): 644-652, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31851836

RESUMO

In the current scenario, there is a rising interest in the treatment of greywater to be used for non-potable purposes. However, there is a need to understand the role of plants in the treatment process. In this context, this paper addresses the comparison of the treatment efficiency of planted systems with the unplanted system. Thus, three gravel-based constructed wetlands were made, i.e., one without plants and two with plants (Typha latifolia and Phragmites australis). The wetland system was used in batch mode operation. The results suggested that the efficacy of the planted system was better than the unplanted system. The removal efficiency of different physicochemical parameters (Chemical oxygen demand, Biochemical oxygen demand, Solids and Total kjeldahl nitrogen) were observed to be more in planted system(61, 43,23 and 25% respectively for plant-1(P-1) system and; 51, 29, 23, and 27% respectively for plant-2 (P-2) system) as compared to the unplanted system(38, 15, 18, and 14% respectively). In addition, it was also observed that P. australis cannot sustain for a longer time in the treatment process but it recovers after some time.


Assuntos
Typhaceae , Áreas Alagadas , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Nitrogênio , Eliminação de Resíduos Líquidos
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