ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2019
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IF 7.149
Jiyuan Jin,Shujuan Zhang,Bingdang Wu,Zhihao Chen,Guoyang Zhang,Paul G. Tratnyek
Quinones are important electron shuttles as well as micropollutants in the nature. Acetylacetone (AA) is a newly recognized electron shuttle in aqueous media exposed to UV irradiation. Herein, we studied the interactions between AA and hydroquinone (QH2) under steady-state and transient photochemical conditions to clarify the possible reactions and consequences if QH2 and AA coexist in a solution. Steady-state experimental results demonstrate that the interactions between AA and QH2 were strongly affected by dissolved oxygen. In O2-rich solutions, the phototransformation of QH2 was AA-independent. Both QH2 and AA utilize O2 as the electron acceptor, but in O2-insufficient solutions, AA became an important electron acceptor for the oxidation of QH2. In all cases, the coexistence of AA increased the phototransformation of QH2, whereas the decomposition of AA in O2-saturated and oversaturated solutions was inhibited by the presence of QH2. The underlying mechanisms were investigated by a combination of laser flash photolysis (LFP) and reduction potential analysis. The LFP results show that the excited AA serves as a better electron shuttle than QH2. As a consequence, AA might regulate the redox cycling of quinones, leading to significant effects on many processes, ranging from photosynthesis and respiration to photodegradation.
研究领域:
环境科学
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光化学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Kai Liu,Fangbai Li,Yan Pang,Liping Fang,Rosalie Hocking
The redox process of electron shuttles like cysteine on iron minerals under aerobic conditions may largely determine the fate of arsenic (As) in soils, while the interfacial processes and underlying mechanisms are barely explored. This work systematically investigates the interfacial oxidation processes of As(III) on goethite induced by cysteine. Results show that the addition of cysteine significantly enhances the oxidation efficiency (~ 40%) of As(III) (C 0 : 10 mg/L) by goethite at pH 7 under aerobic conditions, which is 19.5 times of that without cysteine. cysteine induces Fe(III) reduction on the surface of goethite, and the generation absorbed Fe(II) species play an important role in As(III) oxidation. In particular, the further complexation of Fe(II) with cysteine is thermodynamically favorable for electron transfer , leading to an enhanced As(III) oxidation efficiency. The oxidation efficiency of As(III) in the goethite/cysteine system increases by increasing cysteine concentration and decreases by elevating pH conditions. In addition, evidence indicates that •O 2 - radicals account for approximately 80% of total oxidized As(III). Meanwhile, only 16% of As(III) oxidation can be attributed to the formed •OH radicals. This work provides new insight into the role of organic electron shuttling compounds in determining As cycling in soils.
研究领域:
环境科学
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土壤学
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Yixin Huang,Jinbin Lin,Jing Zou,Jiaxin Xu,Mengyun Wang,Huahua Cai,Baoling Yuan,Jun Ma
Horseradish peroxidase (HRP)-catalyzed hydrogen peroxide (H 2 O 2 ) oxidation could degrade a variety of organic pollutants, but the intrinsic drawback of slow degradation rate limited its widespread application. In this study, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) was introduced into HRP/H 2 O 2 system as an electron shuttle to enhance diclofenac degradation under neutral pH conditions. The green-colored ABTS radical (ABTS •+ ), generated by the oxidation of ABTS with HRP-catalyzed H 2 O 2 oxidation, was proved to be the main reactive species for the rapid degradation of diclofenac in HRP/H 2 O 2 /ABTS system. There was no destruction of ABTS/ABTS •+ in HRP/H 2 O 2 /ABTS system, and ABTS was verified as an ideal electron shuttle. The reaction conditions including solution pH (4.5–10.5), HRP concentration (0–8 units mL −1 ) and H 2 O 2 concentration (0–500 μM) would impact the formation of ABTS •+ , and affect the degradation of diclofenac in HRP/H 2 O 2 /ABTS system. Moreover, compared with Fenton and hydroxylamine/Fenton systems, HRP/H 2 O 2 /ABTS system had better diclofenac degradation efficiency, higher H 2 O 2 utilization efficiency and stronger anti-interference capacity in actual waters. Overall, the present study provided a meaningful and promising way to enhance the degradation of organic pollutants in water with HRP-catalyzed H 2 O 2 oxidation.
研究领域:
环境科学
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生物化学
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PubMed
高影响因子
Journal of Geophysical Research-Biogeosciences
·
2025
·Vol. 130
·期 3
·e2024JG008675
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IF 3.5
Zhengqi Su,Huaming Guo,Zhipeng Gao,Tiantian Ke,Xiaojun Feng,Lingzhi Zhang
Although the reduction of pentavalent arsenic (As(V)) bound to Fe(III) (hydr)oxides (As(V)-containing FeOOH) coupled with organic matter (OM) degradation has received extensive attention, little is known about in situ reduction of FeOOH mineral-bound As(V) (As(V) (s) ) via electron shuttling in the presence of As(V)-reducing bacteria (AsRB). Here, anthraquinone-2,6-disulfonate (AQDS), Suwannee River humic acid (SRHA), and fulvic acid (SRFA) were used to establish an agar electron shuttle system with ferrihydrite-As(V)/goethite-As(V) and AsRB, which was isolated from high-As groundwater as the candidate strain (RA-1). We found that AQDS was more efficient in shuttling electrons to reduce As(V) (s) and Fe(III) than SRHA and SRFA. High contents of quinone moieties in AQDS indicated that quinone moieties were conducive to As(V) (s) and Fe(III) reduction. The reduction kinetic rates ( K red ) of As(V) (s) were higher than those of Fe(III), indicating the occurrence of in situ As(V) (s) reduction via electron shuttling. Furthermore, K red of As(V) (s) for ferrihydrite-As(V) systems was greater than that of goethite-As(V) systems, demonstrating that As(V) bound to ferrihydrite via monodentate was more easily reduced than that bound to goethite via bidentate. The relative expression levels of As metabolic genes ( ars C, arr A, and ars B) initially increased and then decreased in the late stage of experiments. High As concentrations in suspension inhibited the transcriptional activity of As metabolic genes in the late stage, reducing the electron production efficiency of RA-1 and subsequently slowing in situ reduction of As(V) (s) . This study highlights the importance of OM electron shuttling in the reduction of As(V) (s) , offering new perspectives in As enrichment in groundwater. Plain Language Summary OM can promote microbial As(V) reduction in high As groundwater systems. As a result, we explored how FeOOH mineral-bound As(V) could be in situ reduced via electron shuttling between AsRB and different OM. Our findings showed that AQDS was more effective than other two natural organic matter (NOM, i.e., SRHA and SRFA) in reducing both As(V) (s) and Fe(III), due to its high content of quinone moieties. The results of kinetic analysis demonstrated in situ reduction of As(V) (s) , and As(V) bound to ferrihydrite was more readily reduced than As(V) bound to goethite. In addition, the transcriptional activities of three As metabolic genes initially increased but later declined due to high As concentrations, which further slowed the As(V) (s) reduction process. Overall, these findings provide new insights into organic-mediated As cycling in contaminated groundwater. Key Points High quinone contents in AQDS led to a higher reduction extent of As(V) (s) than in SRHA and SRFA The values of K red, As were greater than those of K red, Fe , demonstrating in situ reduction of As(V) (s) Changes in As metabolic genes affected the electron production efficiency of RA-1 and As(V) (s) reduction
研究领域:
环境科学
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微生物学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2025
·
IF 11.3
Xiaojun Feng,Yao Li,Jianyi Jin,Wen Qiao,Zhipeng Gao,Huaming Guo
Little is known about the electron shuttle ability of dissolved organic matter (DOM) and its effects on arsenic (As) mobilization, which makes the underlying mechanism of groundwater As enrichment elusive. In this study, both the electrochemical properties and molecular compositions of DOM in high As groundwater were quantified in the Hetao Basin, China. We found that, along the flow path, the average electron-transferring capacity (ETC) of DOM, including the capacities of electron-accepting and electron-donating, continuously increased from 2.85 to 3.59 mmole-/gC along with As concentrations. The increasing ETC reflected an increase in electron shuttle ability of DOM. Furthermore, the increasing electron shuttle ability was mainly attributed to the recalcitrant compounds in DOM, especially CHOS and CHONS formulas in highly unsaturated structures with high oxygen (HUSHO) and CHO and CHON formulas in aromatic structures (AS). The significantly positive correlation between As concentration and ETC indicated that recalcitrant DOM promoted groundwater As enrichment through electron shuttling for inducing the reductive dissolution of As-containing Fe(III) oxide minerals, which was further supported by our culture experiments showing that goethite was more reduced [133 μM Fe(II)] in the presence of DOM with a higher ETC (3.35 mmole-/gC) as electron shuttling than that [65.2 μM Fe(II)] with a relatively lower ETC (2.41 mmole-/gC). Our study highlights that recalcitrant DOM compounds with unsaturated and AS have high electron shuttle ability, promoting As enrichment in groundwater.
研究领域:
环境科学
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地球化学
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Jiaxin Xu,Jing Zou,Jianying Wu,Huiping Zeng,Yixin Huang,Jingxin Yang,Chunming Gong,Siying Chen,Jun Ma
Chlorination, one of the most common oxidation strategies, performed limited degradation capacity towards many emerging organic contaminants under neutral pH conditions. In this study, 2,2′-azinobis(3-ethylbenzothiazoline)-6-sulfonate (ABTS) was discovered to possess an outstanding activation property towards free available chlorine (FAC) during the chlorination of diclofenac (DCF) among pH 6.0–9.5. ABTS radical (ABTS •+ ) primarily accounted for the elimination of DCF in the ABTS/FAC system, although hydroxyl radicals , reactive chlorine species, and singlet oxygen were also generated via the self-decomposition of FAC. ABTS acted as the electron shuttle to degrade DCF in the ABTS/FAC system, where ABTS was firstly oxidized by FAC to ABTS •+ via single electron transfer , and followed by the elimination of DCF with the generated ABTS •+ . Eight DCF degradation intermediates were identified by LC/Q-TOF/MS, and four DCF degradation pathways were proposed. Real water bodies, humic acid , and the coexistent anions of Cl − , HCO 3 − , NO 3 − , and SO 4 2− performed negligible influence on DCF removal in ABTS/FAC system. ABTS/FAC system was much superior to sole chlorination in terms of toxicity reduction and anti-interference capacity. Overall, this study innovatively introduced ABTS as the electron shuttle to enhance the oxidative capacity of FAC under neutral pH conditions and provided a new insight that the ABTS-like organic/synthetic components might play an important role in degrading emerging organic contaminants by chlorination in water treatment .
研究领域:
环境科学
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水处理工程
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DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2014
·
IF 0.987
Jie Tang,Yunjun Hu,Shams Ali Baig,Tiantian Sheng,Xinhua Xu
The potential of Cr(VI) reduction by Escherichia coli in the presence of soluble Fe(III) was investigated to explore the chemo-biologically mediated reduction process under anaerobic condition. The reduction efficiency of Cr(VI) reached 95% within 24 h. The influences of experimental parameters, including initial pH, temperature, Fe(III) dosage, carbon source, and chelating agent, were also investigated. The highest efficiency of reduction was observed when pH was 5.8 and temperature was 32°C. Amendments of culture medium with Fe(III) and citric-3Na enhanced Cr(VI) reduction, while the addition of EDTA-2Na inhibited the process. Analysis showed that soluble Fe(III) enhanced the reduction process by shuttling electrons from bio-reduced Fe(II) to Cr(VI) in a coupled biotic-abiotic cycle and hence, Cr(VI) was reduced to Cr(III) followed by deposition to sludge.
研究领域:
环境微生物学
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污染治理
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2025
·
IF 9
Dun Guo,Lei Yang,Hao-Qi Lu,Yu-Chao Wang,Hong-Yan Meng,Pan Liang,Shen Cui,Zhang-Wei He,Jun Lan,Yong-Xiang Ren
Optimizing electron shuttles and revealing their mediating mechanisms are crucial for enhancing the ammonium (NH 4 + -N) oxidation coupled with Fe (III) reduction. In this study, anthraquinone-2,6-disulfonate (AQDs), riboflavin (RF), and humic acid (HA) were optimized in batch tests. The optimal dosages of 6, 2, and 8 mg/L for AQDs, RF, and HA resulted in average maximum NH 4 + -N removal of 80.2 %, 88.5 %, and 99.2 %, with 91.4 %, 88.5 %, and 74.7 % of the removed NH 4 + -N converted to nitrate, respectively. In addition, an enhanced extracellular electron transfer was also observed, including an enlarged current, diversified REDOX pathway, and reduced resistance. Outperformed AQDs in nitrogen removal and microbial activity, HA and RF were selected for the subsequent 100-day long-term investigation. During this stage, excess influent Fe tended to be stored as insoluble coatings on the sludge surface, while RF and HA facilitated its use to compensate for the reduced influent Fe 3+ . Meanwhile, they led to an increase in iron-reducing ( Comamonas ) and NH 4 + -N oxidizing bacteria ( Nitropsira and Planctomycetes ), as well as improvements in electrochemical characteristics and microbial activity. Moreover, microbial N and Fe metabolic potential were efficiently enhanced. Consequently, NH 4 + -N and TN removal rates were obviously increased to approximately 90 % and 40 %, respectively. The addition of electron shuttles led to long-term improvements in extracellular mass transfer and microbial metabolism, which contributed more than bridging the extracellular electron transfer. These results deepened the understanding of the effect of electron shuttles on Feammox.
研究领域:
环境科学
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微生物学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Jinbin Lin,Yuye Hu,Junyang Xiao,Yixin Huang,Mengyun Wang,Haoyu Yang,Jing Zou,Baoling Yuan,Jun Ma
Fe(II)/peracetic acid (Fe(II)/PAA) process exhibits a great potential in abatement of micropollutants because of the fast reaction between Fe(II) and PAA. Similar to Fenton system, the slow reduction from Fe(III) to Fe(II) leads to the high dosage of Fe(II) in Fe(II)/PAA process. This study introduced 2,2′-azino-bis(3-ethylbenz- -othiazoline-6-sulfonate) (ABTS) as electron shuttle to improve the oxidation capacity of Fe(II)/PAA process by accelerating the redox cycle of Fe(III)/Fe(II). ABTS/Fe(II)/PAA process possessed high elimination efficiency of diclofenac in acidic conditions. Alcohols quenching experiments confirmed that ABTS •+ was the primary reactive species responsible for diclofenac elimination, although Fe IV O 2+ and carbon-centered radicals (R-O • ) also existed in ABTS/Fe(II)/PAA process. ABTS •+ was generated via various pathways, including the reactions of ABTS with Fe(III), Fe IV O 2+ and R-O • . ABTS was not an ideal electron shuttle because R-O • could decompose partial ABTS •+ to sulfoxides and sulfones. Two possible degradation pathways of diclofenac were proposed based on the detected transformation products. ABTS/Fe(II)/PAA process was highly-efficient for diclofenac elimination in underground water and reservoir water, while high concentration of humic acid had inhibition effect on diclofenac degradation. The present study provides a promising way to alleviate the intrinsic drawbacks of Fe(II)/PAA process and might advance its potential application in water treatment.
研究领域:
环境科学
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水处理技术
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DOI
高影响因子
Journal of Environmental Sciences
·
2021
·
IF 5.565
Cholnam Ri,Jingchun Tang,Feng Liu,Honghong Lyu,Fengxiang Li
Biochar, carbonaceous material produced from biomass pyrolysis, has been demonstrated to have electron transfer property (associated with redox active groups and multi condensed aromatic moiety), and to be also involved in biogeochemical redox reactions. In this study, the enhanced removal of Cr(VI) by Shewanella oneidensis MR-1(MR-1) in the presence of biochars with different pyrolysis temperatures (300 to 800 °C) was investigated to understand how biochar interacts with Cr(VI) reducing bacteria under anaerobic condition. The promotion effects of biochar (as high as 1.07~1.47 fold) were discovered in this process, of which the synergistic effect of BMBC700(ball milled biochar) and BMBC800 with MR-1 was noticeable, in contrast, the synergistic effect of BMBCs (300–600 °C) with MR-1 was not recognized. The more enhanced removal effect was observed with the increase of BMBC dosage for BMBC700+MR-1 group. The conductivity and conjugated O-containing functional groups of BMBC700 particles themselves has been proposed to become a dominant factor for the synergistic action with this strain. And, the smallest negative Zeta potential of BMBC700 and BMBC800 is thought to favor decreasing the distance from microbe than other BMBCs. The results are expected to provide some technical considerations and scientific insight for the optimization of bioreduction by useful microbes combining with biochar composites to be newly developed.
研究领域:
环境微生物学
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污染治理
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
·
IF 13.273
Xiaotong Shen,Jian Zhang,Huijun Xie,Bo Sun,Shuang Liang,Haiming Wu,Zhen Hu,Huu Hao Ngo,Wenshan Guo,Jiaxing Lu
Mn oxides could realize persistent organic pollutants (POPs) removal through the cycle of Mn between Mn(II) and biogenic Mn oxides in constructed wetlands (CWs) filled with Mn oxides. However, the inefficient cycle of Mn caused by the limited oxidation ability of Mn oxides inhibited its effective degradation of POPs. Ruthenium (Ru) and 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonate (ABTS) could act as electron shuttles in catalytic Mn oxides oxidation process. In this study, phenanthrene (PHE) was selected as a typical POP and biochar (BC) supported Ru (Ru/BC) and ABTS (ABTS/BC) were induced in CWs with Mn oxides (birnessite). The removal efficiencies of PHE in CWs with Ru/BC and ABTS/BC reached 94.61% and 95.51%, higher than the control (79.91%). ABTS performed best for enhancing Mn cycle based on the results of highest oxidation removal capacity and relative abundance of Mn-oxidizing bacteria. What’s more, the addition of Ru/BC contributed to the best adsorption ability and highest relative abundance of PHE degrading bacteria.
研究领域:
环境科学
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微生物学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
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IF 11.3
Wen Qin,Chengyuan Zheng,Haoming Qin,Yang Song,Yang Zhou,Jin Jiang,Jun Ma
Permanganate/electron shuttle systems for the enhanced transformation of anilines were evaluated. The presence of electron shuttles (2,2’-azino-bis(3-ethylbenzothiazoline)-6-sulfonate (ABTS), 1-hydroxybenzotriazole (HBT) and catechol (CAT) accelerated the oxidative transformation of aniline by Mn(VII). In the Mn(VII)/ABTS process, ABTS •+ was partially consumed through fragmentation or polymerization with aniline, while the second-order rate constants ( k app 2 , M −1 s −1 ) of the interaction of ABTS •+ with aniline rose from 86.57 to 140.04 M −1 s −1 with increase in pH from 5 to 8. In the Mn(VII)/HBT system, aniline removal was markedly enhanced under acidic conditions due to the formation of polymerized products via radical cations (HBT • ). Furthermore, the oxidative transformation of aniline (82.5 %) by Mn(VII)/CAT was significantly higher than that by Mn(VII) (65.2 %) because of Michael addition reaction of aniline and ortho-benzoquinone (o-BQ). Moreover, the formation of Mn(III) was confirmed by the overall oxidation state (3.13) and the X-ray Photoelectron Spectroscopy (XPS) spectra of the Mn products in the CAT/Mn(VII) process, revealing a synergistic mechanism between o-BQ and Mn(III) for enhanced aniline degradation.
研究领域:
环境科学
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化学
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产品关联
DOI
PubMed
高影响因子