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Lena Q - One of the best experts on this subject based on the ideXlab platform.
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arsenic removal from as hyperaccumulator Pteris vittata biomass coupling extraction with precipitation
Chemosphere, 2018Co-Authors: Evandro B Da Silva, Letuzia M De Oliveira, Ann C Wilkie, Lena QAbstract:Abstract Proper disposal of As-hyperaccumulator Pteris vittata biomass (Chinese brake fern) enhances its application in phytoremediation. The goal of this study was to optimize As removal from P. vittata (PV) biomass by testing different particle sizes, extractants, extraction times and solid-to-liquid ratios. PV biomass was extracted using different extractants followed by different Mg-salts to recover soluble As via precipitation. Water-soluble As in PV biomass varied from 6.8% to 61% of total As depending on extraction time, with 99% of As being arsenate (AsV). Extraction with 2.1% HCl, 2.1% H3PO4, 1 M NaOH and 50% ethanol recovered 81, 78, 47 and 14% of As from PV biomass. A follow-up extraction using HCl recovered 27–32% with ethanol recovering only 5%. Though ethanol showed the lowest extractable As, residual As in the biomass was also the lowest. Among the extractants, 35% ethanol was the best to remove As from PV biomass. Approximately 90% As was removed from PV biomass using particle size
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mechanisms of efficient as solubilization in soils and as accumulation by as hyperaccumulator Pteris vittata
Environmental Pollution, 2017Co-Authors: Bala Rathinasabapathi, Lena Q, Hongbo Li, Yanshan ChenAbstract:Abstract Arsenic (As) in soils is of major environmental concern due to its ubiquity and carcinogenicity. Pteris vittata (Chinese brake fern) is the first known As-hyperaccumulator, which is highly efficient in extracting As from soils and translocating it to the fronds, making it possible to be used for phytoremediation of As-contaminated soils. In addition, P. vittata has served as a model plant to study As metabolisms in plants. Based on the recent advances, we reviewed the mechanisms of efficient As solubilization and transformation in rhizosphere soils of P. vittata and effective As uptake, translocation and detoxification in P. vittata. We also provided future research perspectives to further improve As phytoremediation by P. vittata.
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arsenic uptake arsenite efflux and plant growth in hyperaccumulator Pteris vittata role of arsenic resistant bacteria
Chemosphere, 2016Co-Authors: Jingwei Fu, Lena Q, Bala Rathinasabapathi, Yanshan ChenAbstract:Abstract Bacteria-mediated arsenic (As) transformation and their impacts on As and P uptake and plant growth in As-hyperaccumulator Pteris vittata (PV) were investigated under sterile condition. All As-resistant bacteria (9 endophytic and 6 rhizospheric) were As-reducers except one As-oxidizer. After growing two months in media with 37.5 mg kg−1 AsV, As concentrations in the fronds and roots were 3655–5389 (89–91% AsIII) and 971–1467 mg kg−1 (41–73% AsIII), corresponding to 22–52% decrease in the As in the media. Bacterial inoculation enhanced As and P uptake by up to 47 and 69%, and PV growth by 20–74%, which may be related to elevated As and P in plants (r = 0.88–0.97, p
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high as exposure induced substantial arsenite efflux in as hyperaccumulator Pteris vittata
Chemosphere, 2016Co-Authors: Yanshan Chen, Lena Q, Bala Rathinasabapathi, Jingwei FuAbstract:Abstract Arsenite (AsIII) efflux is an important mechanism for arsenic (As) detoxification in plants. Low AsIII efflux has been observed in As-hyperaccumulator Pteris vittata , which may contribute to its highly efficient As translocation and accumulation; however, the results may be compromised by microbial AsIII oxidation, relatively low As concentration in the medium and short-term As exposure. Here, sterile P. vittata sporophytes were cultivated in sterile medium containing 10, 200 and 500 µM arsenate (AsV) for 28 d. Arsenite efflux to the growth medium and As speciation in P. vittata was investigated. Low AsIII efflux at 12% of AsV uptake was observed at 10 µM AsV, but high AsIII efflux (36–76%) was observed at 200 and 500 µM AsV, with 1987–2397 mg kg −1 As being accumulated in the fronds. This is the first report to show efficient AsIII efflux in P. vittata . This study showed that P. vittata may use high AsIII efflux to cope with As toxicity under high As exposure, which may be necessary to sustain growth while accumulating As.
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transfer of arsenic and phosphorus from soils to the fronds and spores of arsenic hyperaccumulator Pteris vittata and three non hyperaccumulators
Plant and Soil, 2015Co-Authors: Jason T. Lessl, Dong Xing Guan, Emily Sessa, Lena Q, Bala RathinasabapathiAbstract:Background and aims Concentrations of chemical analogs arsenic (As) and phosphorus (P) were measured in As-hyperaccumulator (Pteris vittata; PV) and three non As-hyperaccumulators (ThelyPteris kunthii, Nephrolepsis brownii, and N. falcata) to draw inferences regarding their uptake from soils to roots and translocation to fronds and spores.
Bala Rathinasabapathi - One of the best experts on this subject based on the ideXlab platform.
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mechanisms of efficient as solubilization in soils and as accumulation by as hyperaccumulator Pteris vittata
Environmental Pollution, 2017Co-Authors: Bala Rathinasabapathi, Lena Q, Hongbo Li, Yanshan ChenAbstract:Abstract Arsenic (As) in soils is of major environmental concern due to its ubiquity and carcinogenicity. Pteris vittata (Chinese brake fern) is the first known As-hyperaccumulator, which is highly efficient in extracting As from soils and translocating it to the fronds, making it possible to be used for phytoremediation of As-contaminated soils. In addition, P. vittata has served as a model plant to study As metabolisms in plants. Based on the recent advances, we reviewed the mechanisms of efficient As solubilization and transformation in rhizosphere soils of P. vittata and effective As uptake, translocation and detoxification in P. vittata. We also provided future research perspectives to further improve As phytoremediation by P. vittata.
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arsenic uptake arsenite efflux and plant growth in hyperaccumulator Pteris vittata role of arsenic resistant bacteria
Chemosphere, 2016Co-Authors: Jingwei Fu, Lena Q, Bala Rathinasabapathi, Yanshan ChenAbstract:Abstract Bacteria-mediated arsenic (As) transformation and their impacts on As and P uptake and plant growth in As-hyperaccumulator Pteris vittata (PV) were investigated under sterile condition. All As-resistant bacteria (9 endophytic and 6 rhizospheric) were As-reducers except one As-oxidizer. After growing two months in media with 37.5 mg kg−1 AsV, As concentrations in the fronds and roots were 3655–5389 (89–91% AsIII) and 971–1467 mg kg−1 (41–73% AsIII), corresponding to 22–52% decrease in the As in the media. Bacterial inoculation enhanced As and P uptake by up to 47 and 69%, and PV growth by 20–74%, which may be related to elevated As and P in plants (r = 0.88–0.97, p
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high as exposure induced substantial arsenite efflux in as hyperaccumulator Pteris vittata
Chemosphere, 2016Co-Authors: Yanshan Chen, Lena Q, Bala Rathinasabapathi, Jingwei FuAbstract:Abstract Arsenite (AsIII) efflux is an important mechanism for arsenic (As) detoxification in plants. Low AsIII efflux has been observed in As-hyperaccumulator Pteris vittata , which may contribute to its highly efficient As translocation and accumulation; however, the results may be compromised by microbial AsIII oxidation, relatively low As concentration in the medium and short-term As exposure. Here, sterile P. vittata sporophytes were cultivated in sterile medium containing 10, 200 and 500 µM arsenate (AsV) for 28 d. Arsenite efflux to the growth medium and As speciation in P. vittata was investigated. Low AsIII efflux at 12% of AsV uptake was observed at 10 µM AsV, but high AsIII efflux (36–76%) was observed at 200 and 500 µM AsV, with 1987–2397 mg kg −1 As being accumulated in the fronds. This is the first report to show efficient AsIII efflux in P. vittata . This study showed that P. vittata may use high AsIII efflux to cope with As toxicity under high As exposure, which may be necessary to sustain growth while accumulating As.
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transfer of arsenic and phosphorus from soils to the fronds and spores of arsenic hyperaccumulator Pteris vittata and three non hyperaccumulators
Plant and Soil, 2015Co-Authors: Jason T. Lessl, Dong Xing Guan, Emily Sessa, Lena Q, Bala RathinasabapathiAbstract:Background and aims Concentrations of chemical analogs arsenic (As) and phosphorus (P) were measured in As-hyperaccumulator (Pteris vittata; PV) and three non As-hyperaccumulators (ThelyPteris kunthii, Nephrolepsis brownii, and N. falcata) to draw inferences regarding their uptake from soils to roots and translocation to fronds and spores.
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characterization of arsenic resistant endophytic bacteria from hyperaccumulators Pteris vittata and Pteris multifida
Chemosphere, 2014Co-Authors: Dong Xing Guan, Lena Q, Bala RathinasabapathiAbstract:We isolated and characterized As-resistant endophytic bacteria (AEB) from two arsenic hyperaccumulators. Their plant growth promoting traits and the relation between As tolerance and transformation were evaluated. A total of 41 and 33 AEB were isolated from Pteris vittata (PV) and Pteris multifida (PM) respectively. PV AEB represented 2 genera while PM AEB comprised of 12 genera, with Bacillus sp. being the most dominant bacteria from both plants. All AEB had limited ability in solubilizing P and producing indole acetic acid (IAA) and siderophore. All isolates tolerated 10 mM arsenate (As(V)), with PV isolates being more tolerant to As(V) and PM more tolerant to arsenite (As(III)). Bacterial arsenic tolerance was related to their ability in As(III) oxidation and As(V) reduction as well as their ability to retain As in the biomass to a varying extent. Though AEB showed limited plant growth promoting traits, they were important in arsenic tolerance and speciation in plants.
Tongbin Chen - One of the best experts on this subject based on the ideXlab platform.
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comparison among soil additives for enhancing Pteris vittata l phytoremediation of as contaminated soil
International Journal of Phytoremediation, 2018Co-Authors: Jun Yang, Shushen Yang, Junxing Yang, Tongbin Chen, Xiaoling WangAbstract:AbstractPot experiments were conducted to assess the effects of monoammonium phosphate (NH4H2PO4) and citric acid (CA) on the arsenic uptake of Chinese brake fern (Pteris vittata L. in two typical ...
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A Comparison of Arsenic Speciation in 13 Pteris vittata L. Populations
Spectroscopy and Spectral Analysis, 2015Co-Authors: Zechun Huang, Tongbin ChenAbstract:Synchrotron radiation X-ray absorption near edge structure was employed to study the arsenic (As) speciation in 13 Pteris vittata L. populations collected from 7 provinces, cities, and autonomous regions in China. As in roots of P. vittata was mainly combined with oxygen (0), with a small amount of As combined with glutathione (GSH). Populations from Hunan and Guangxi provinces showed higher percentages of As-GSH in soots. As in roots of P. vittata was predominated with As( V), with the percentage of As(V) V) to the total As being 59. 6 +/- 0. 6%similar to 83. 8 +/- 3. 8%. The As(V) V) percentage was in the order of HN5 HN3>HN1>TW>CQ>AH>FJ>HN5>HN2>GX2>GX3>HN4>GX1, within the range of 2. 4%similar to 12. 9%. Different from that in roots, As in shoots was predominated with As(III), with no As() detected. The disclosure of As speciation in the roots and shoots of P. vittata contributes to the future research on As accumulation mechanism.
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role of transpiration in arsenic accumulation of hyperaccumulator Pteris vittata l
Environmental Science and Pollution Research, 2015Co-Authors: Tongbin Chen, Junxing Yang, Yang ChenAbstract:Mechanisms of Pteris vittata L. to hyperaccumulate arsenic (As), especially the efficient translocation of As from rhizoids to fronds, are not clear yet. The present study aims to investigate the role of transpiration in the accumulation of As from the aspects of transpiration regulation and ecotypic difference. Results showed that As accumulation of P. vittata increased proportionally with an increase in the As exposure concentration. Lowering the transpiration rate by 28∼67 % decreased the shoot As concentration by 19∼56 %. Comparison of As distribution under normal treatment and shade treatment indicated that transpiration determines the distribution pattern of As in pinnae. In terms of the ecotypic difference, the P. vittata ecotype from moister and warmer habitat had 40 % higher transpiration and correspondingly 40 % higher shoot As concentration than the ecotype from drier and cooler habitat. Results disclosed that transpiration is the main driver for P. vittata to accumulate and re-distribute As in pinnae.
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CHARACTERIZATION OF ARSENIC UPTAKE IN LIVING Pteris vittata L
Instrumentation Science & Technology, 2014Co-Authors: Xiaoyong Zhou, Jun Yang, Tongbin Chen, Guang-dong ZhouAbstract:Phytoremediation of arsenic contamination using the hyperaccumulator Pteris vittata is an active area of research. However, the mechanism for the uptake of arsenic in P. vittata remains unclear, due to the absence of methods to monitor this process. This study utilized synchrotron radiation X-ray fluorescence (XRF) spectroscopy and X-ray absorption near-edge structure (XANES) to continuously observe in situ arsenic in living P. vittata. The results showed that the reduction of arsenic(V) to arsenic(III) occurred simultaneously with an increase in frond arsenic, suggesting the reduction affected arsenic uptake. In situ XRF measurements of living P. vittata accurately characterized arsenic uptake but in situ XANES could not be used on live plants without using methods to prevent radiation damage. A novel approach is reported to investigate the changes of elements in plants.
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arsenic transformation and volatilization during incineration of the hyperaccumulator Pteris vittata l
Environmental Science & Technology, 2008Co-Authors: Tongbin Chen, Xiaoyong Liao, Zechun Huang, Tiandou HuAbstract:Safe incineration of harvested hyperaccumulators containing high content of heavy metals to avoid secondary environmental pollution is a problem for popularizing phytoremediation technology. The As volatilization behavior and its mechanism during incineration of Pteris vittata, an As-hyperaccumulator, was investigated. Incineration results reveal that 24% of total As accumulated by P. vittata (H-As) containing high As content (1170 mg/kg) is emitted at 800 °C, of which 62.5% of the total emitted As is volatilized below 400 °C. A study of the extended X-ray absorption fine structure (EXAFS) shows that part of As(III) was identified in the thermal decomposition residue of dried P. vittata (H-As), As2O5 + P. vittata (L-As) containing low As content (14.7 mg/kg), and As2O5 + charcoal (C) at 200 °C, suggesting that carbon originating from biomass incineration might catalyze As(V) reduction. This speculation was tested through thermogravimetric experiments, in which either C or P. vittata (L-As) markedly cataly...
Weihua Zhang - One of the best experts on this subject based on the ideXlab platform.
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thiol synthesis and arsenic hyperaccumulation in Pteris vittata chinese brake fern
Environmental Pollution, 2004Co-Authors: Weihua Zhang, Kelsey R Downum, Lena QAbstract:Abstract Pteris vittata (Chinese brake fern) has potential for phytoremediation of As-contaminated sites. In this study, the synthesis of total thiols and acid-soluble thiols in P. vittata was investigated under arsenic exposure. The strong and positive correlation between As concentration and acid-soluble thiols in plant leaflets suggests that acid-soluble thiols may play a role in As detoxification. A major As-induced thiol was purified and characterized. A molecular ion (M+1) of 540 m / z suggests that the thiol was a phytochelatin (PC) with two base units (PC 2 ). However, the ratios of acid-soluble thiols to As in leaflets exposed to As ranged from 0.012 to 0.026, suggesting that only a very small part of As is complexed by PC 2 . PCs could play a minor detoxification role in this hyperaccumulator. A PC-independent mechanism appears to be mainly involved in As tolerance, while PC-dependent detoxification seems to be a supplement.
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Arsenic complexes in the arsenic hyperaccumulator Pteris vittata (Chinese brake fern).
Journal of Chromatography A, 2004Co-Authors: Weihua Zhang, Kelsey R Downum, Lena QAbstract:Pteris vittata (Chinese brake fern), the first reported arsenic (As) hyperaccumulating plant, can be potentially applied in the phytoremediation of As-contaminated sites. Understanding the mechanisms of As tolerance and detoxification in this plant is critical to further enhance its capability of As hyperaccumulation. In this study, an unknown As species, other than arsenite (AsIII) or arsenate (AsV) was found in leaflets by using anion-exchange chromatography–hydride generation–atomic fluorescence spectroscopy and size-exclusion chromatography–atomic fluorescence spectrometry. The chromatographic behavior of this unknown As species and its stability suggest that it is likely an As complex. Although phytochelatin with two subunits (PC2) was the only major thiol in P. vittata under As exposure, this unknown As complex was unlikely to be an AsIII–PC2 complex by comparison of their chromatographic behaviors, stability at different pHs and charge states. The complex is sensitive to temperature and metal ions, but relatively insensitive to pH. In buffer solution of pH 5.9, it is present in a neutral form.
Yanshan Chen - One of the best experts on this subject based on the ideXlab platform.
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mechanisms of efficient as solubilization in soils and as accumulation by as hyperaccumulator Pteris vittata
Environmental Pollution, 2017Co-Authors: Bala Rathinasabapathi, Lena Q, Hongbo Li, Yanshan ChenAbstract:Abstract Arsenic (As) in soils is of major environmental concern due to its ubiquity and carcinogenicity. Pteris vittata (Chinese brake fern) is the first known As-hyperaccumulator, which is highly efficient in extracting As from soils and translocating it to the fronds, making it possible to be used for phytoremediation of As-contaminated soils. In addition, P. vittata has served as a model plant to study As metabolisms in plants. Based on the recent advances, we reviewed the mechanisms of efficient As solubilization and transformation in rhizosphere soils of P. vittata and effective As uptake, translocation and detoxification in P. vittata. We also provided future research perspectives to further improve As phytoremediation by P. vittata.
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arsenic uptake arsenite efflux and plant growth in hyperaccumulator Pteris vittata role of arsenic resistant bacteria
Chemosphere, 2016Co-Authors: Jingwei Fu, Lena Q, Bala Rathinasabapathi, Yanshan ChenAbstract:Abstract Bacteria-mediated arsenic (As) transformation and their impacts on As and P uptake and plant growth in As-hyperaccumulator Pteris vittata (PV) were investigated under sterile condition. All As-resistant bacteria (9 endophytic and 6 rhizospheric) were As-reducers except one As-oxidizer. After growing two months in media with 37.5 mg kg−1 AsV, As concentrations in the fronds and roots were 3655–5389 (89–91% AsIII) and 971–1467 mg kg−1 (41–73% AsIII), corresponding to 22–52% decrease in the As in the media. Bacterial inoculation enhanced As and P uptake by up to 47 and 69%, and PV growth by 20–74%, which may be related to elevated As and P in plants (r = 0.88–0.97, p
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high as exposure induced substantial arsenite efflux in as hyperaccumulator Pteris vittata
Chemosphere, 2016Co-Authors: Yanshan Chen, Lena Q, Bala Rathinasabapathi, Jingwei FuAbstract:Abstract Arsenite (AsIII) efflux is an important mechanism for arsenic (As) detoxification in plants. Low AsIII efflux has been observed in As-hyperaccumulator Pteris vittata , which may contribute to its highly efficient As translocation and accumulation; however, the results may be compromised by microbial AsIII oxidation, relatively low As concentration in the medium and short-term As exposure. Here, sterile P. vittata sporophytes were cultivated in sterile medium containing 10, 200 and 500 µM arsenate (AsV) for 28 d. Arsenite efflux to the growth medium and As speciation in P. vittata was investigated. Low AsIII efflux at 12% of AsV uptake was observed at 10 µM AsV, but high AsIII efflux (36–76%) was observed at 200 and 500 µM AsV, with 1987–2397 mg kg −1 As being accumulated in the fronds. This is the first report to show efficient AsIII efflux in P. vittata . This study showed that P. vittata may use high AsIII efflux to cope with As toxicity under high As exposure, which may be necessary to sustain growth while accumulating As.