Daoyong Zhang

Chinese Academy of Sciences, Peping, Beijing, China

Are you Daoyong Zhang?

Claim your profile

Publications (66)150.28 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Bioreduction of Cr(VI) to less toxic Cr(III) by chromate-reducing bacteria has offered an ecological and economical option for chromate detoxification. The present study reports isolation of chromate-resistant bacterial strain Cr8 from chromium slag, identified as Pseudomonas stutzeri, based on 16S rRNA gene sequencing and their potential use in Cr(VI) reduction. The reduced product associated with bacterial cell was characterized by scanning electron microscopy–energy-dispersive x-ray spectroscopy (SEM-EDS) and x-ray diffraction (XRD) analyses. At initial concentrations of 100 and 200 mg L−1 Cr(VI), P. stutzeri Cr8 reduced Cr(VI) completely within 24 h, whereas it reduced almost 1000 mg L−1 Cr(VI) at the end of 120 h. Further, soil column leaching experiments were performed and found that bacterial cells reduced Cr(VI) leachate at faster rate that almost disappeared at the end of 168 h. The leachate precipitates also revealed efficient chromate bioreduction. The remediation process utilizing P. stutzeri could be considered as a viable alternative to reduce Cr(VI) contamination, especially emanating from the overburden dumps of chromite ores and mine drainage.
    No preview · Article · Oct 2015 · Bioremediation Journal
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Application of the conventional bioreactors based on biosorption for removal of heavy metals is limited because they can be broken through by heavy metals. The novel calcifying cyanobacteria reactors based co-precipitation of heavy metals with carbonate minerals induced by cyanobacteria may be a promising alternative technology to overcome the shortcomings of biosorption. In this study, removal of cadmium (Cd) from wastewater using three calcifying bacterium Nostoc calcicola reactors was investigated. N. calcicola can significantly increase aquatic phase pH in the reactor, associated with a decrease of dissolved inorganic carbon (DIC) content in the effluent. During the two-month operation of the bioreactors, over 98% of Cd removal was obtained with an initial Cd2+ concentration of 2.5 μM. Cd2+ was mainly sequestrated in organic-bound fraction, followed by a small amount of carbonate and exchangeable fractions in the N. calcicola cell. A crystalline compound of Ca, C, and O, as well as a small amount of Cd on the surface of N. calcicola cell, was observed. The two-month high Cd removal efficiency of the N. calcicola reactors shows the calcifying cyanobacteria reactors have advantages over the conventional biosorption system, which can be shortly broken through for removal of heavy metals. Although the results revealed that calcifying cyanobacterium reactor is a promising way to remove Cd from water, assessment of its longer-term performance of heavy metal removal is needed.
    Full-text · Article · Aug 2015 · Ecological Engineering
  • [Show abstract] [Hide abstract]
    ABSTRACT: Acidithiobacillus ferrooxidans is a commonly used bacterial species for leaching gold ores to recover gold. The pH of A. ferrooxidans bioleachates drastically changes from around 2.0 during bioleaching to about pH 8.0 as the cells are discharged together with the mine tailings containing high levels of Hg. It is not known how such a large pH shock would affect the properties of bacterial extracellular polymeric substances (EPS) and the transport of Hg in the mine tailings. In this study, the biochemical composition, molecular distribution, fluorescence properties and Hg(II) complexation by EPS of A. ferrooxidans cultured at pH 2 and 8 were investigated. It was found that pH shock significantly altered the composition of EPS. A. ferrooxidans yielded more EPS under acid conditions than basic conditions. The acidic EPS contained more macromolecular proteins but less polysaccharide in comparison with the basic EPS. Phosphodiester functional groups in phospholipids and polysaccharides were found in the acidic EPS but not in the basic EPS. One tryptophan protein-like peak and one aromatic protein-like peak were identified in fluorescence spectra of the acidic EPS. Two aromatic protein-like peaks were identified from the fluorescence spectra of the basic EPS. The tryptophan protein-like substances in the acidic EPS interacted with Hg(II) and formed relatively stable complexes but with weak binding ability whereas the fluorescent aromatic protein-like substances in the acidic EPS did not bind Hg(II). However the aromatic protein-like substances in the basic EPS had a strong binding ability for Hg(II). The significant differences in composition and Hg complexation ability between EPS from acidic and basic environments indicate that a large pH shock during leaching of gold may exert a considerable impact on the behavior and fate of Hg in the mining areas.
    No preview · Article · Jun 2015 · Geomicrobiology
  • [Show abstract] [Hide abstract]
    ABSTRACT: Acidic copper mine tailings with high levels of heavy metals and arsenic pose a great risk to ecosystems and human beings. Physiological responses and phytoaccumulation of heavy metals and arsenic in Medicago sativa L. growing in soils with various proportions of acidic copper mine tailings were assessed in this study. Seed germination of M. sativa was enhanced by 5-10% tailings but inhibited at higher proportions (30% and 50%) of tailings. Seedling growth, cell membrane and photosynthesis were adversely affected when the plants were grown in soils with high proportions of tailings. The activities of antioxidant enzymes (catalase, superoxide dismutase and guaiocol peroxidase) increased with increasing proportions of tailings, indicating that the antioxidant system was not impaired and can tolerate the toxicity of mine tailings. The plants grew well in soil containing up to 50% of acidic copper mine tailings. Heavy metals and arsenic except Hg were overwhelmingly immobilized in roots. Medicago sativa is a promising plant species for revegetation and phytostabilization of acidic copper mine tailings in arid lands. However, the high mobility of Hg from root to shoot may pose risk to animals.
    No preview · Article · May 2015 · Journal of Geochemical Exploration
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Simultaneous removal of antibiotic tetracycline hydrochloride (TC) and As(III) by poorly-crystalline Mn dioxide was investigated. TC and As(III) can be effectively oxidized and removed by MnO2. High concentrations of TC and As(III) competed with each other for oxidation or adsorption sites on MnO2 and thus affected their removal efficiency. The intermediates and products of TC after reaction with poorly-crystalline manganese dioxide were identified by LC-ESI-MS (liquid chromatography-electrospray ionization-mass spectrometry), and the decomposition pathways of TC by MnO2 were proposed. This study is helpful for understanding the importance of environmental Mn dioxides in the decontamination of combined pollution by organic pollutants and metal(loid)s. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Full-text · Article · May 2015 · Chemosphere
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Oxidative dissolution of natural rhodochrosite by the Mn(II) oxidizing bacterium Pseudomonas putida strain MnB1 was investigated based on batch and electrochemical experiments using natural rhodochrosite as the working electrode. Tafel curves and batch experiments revealed that bacterial exopolymers (EPS) significantly increased dissolution of natural rhodochrosite. The corrosion current significantly increased with reaction time for EPS treatment. However, the corrosion process was blocked in the presence of cells plus extra EPS due to formation of the passivation layer. Moreover, the scanning electron microscopy and the energy dispersive spectroscopy (SEM-EDS) results showed that the surface of the natural rhodochrosite was notably changed in the presence of EPS alone or/and bacterial cells. This study is helpful for understanding the role of EPS in bacterially oxidation of Mn(II). It also indicates that the Mn(II) oxidizing bacteria may exert their effects on Mn(II) cycle and other biological and biogeochemical processes much beyond their local ambient environment because of the catalytically dissolution of solid Mn(II) by EPS and the possible long distance transport of the detached EPS.
    Full-text · Article · May 2015 · Applied Geochemistry
  • [Show abstract] [Hide abstract]
    ABSTRACT: Nitrate and arsenic are common pollutants in groundwater. However, we are still lacking technologies that can remove nitrate and arsenic simultaneously using a single species of microorganism. In the present study, the potential of synchronous removal of nitrate and arsenite from water by a single anaerobic nitrate-reducing Fe(II) oxidizing Citrobacter freundii strain PXL1 was assessed. The strain PXL1 could grow well in arsenite concentration of 2.85–13.65 μM and efficiently oxidize Fe(II), reduce nitrate and remove As(III) from water. Scanning electron microscopy, X-ray diffraction spectroscopy, and Fourier transform infrared spectroscopy analysis showed that the strain PXL1 produced poorly crystalline Fe(III) oxides. As(III) was removed mainly by adsorption and co-precipitation of the biogenic Fe(III) oxides. The anaerobic nitrate-dependent Fe(II) oxidizing bacteria including C. freundii PXL1 are promising microbes for in situ remediation of nitrate and arsenite contaminated groundwater.
    No preview · Article · Apr 2015 · Ecological Engineering
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The microbiology of mining environments has become a research topic of great importance. The present study reports on six bacterial and three fungal isolates which were characterized on a molecular basis. The phylogenetic analysis distributed the bacterial isolates into six groups in which groups A, B and C belonged to Bacillus beringensis, Bacillus sp. and Bacillus megaterium, respectively, while groups D, E and F constituted strains of Pseudomonas putida, Acidothiobacillus sp. and Kocuria sp., respectively. Fungi isolated belonged to the genera Aspergillus, Fusarium and Hypocrea. These isolates showed metal resistances to six heavy metals: Cu, Cr, Pb, Cd, Sb and Ni. For the bacteria, the minimum inhibitory concentrations (MICs) of these metals were in the range of 1-11 mM, whereas for fungi, the MIC was in the range of 5-20 mM. The multiple heavy metal-resistant bacterial species may be further screened for application to bioremediation.
    Full-text · Article · Apr 2015 · Environmental Earth Sciences
  • [Show abstract] [Hide abstract]
    ABSTRACT: Microbial extracellular polymeric substances (EPS) may flocculate or be decomposed when environmental factors change, which significantly influences nutrient cycling and transport of heavy metals. However, little information is available on the stability of EPS in natural environments. Fluorescence and flocculation properties of EPS from Chroococcus minutus under different irradiation and pH conditions were studied. Two aromatic protein-like fluorescence peaks and one tyrosine protein-like peak were identified from the excitation-emission-matrix (EEM) fluorescence spectra of EPS. UVB (ultraviolet B) and solar irradiation increased the fluorescence intensity of all the three peaks while UVC (ultraviolet C) irradiation had little effect. EPS formed unstable flocs after exposure to UV (ultraviolet) irradiation and formed stable flocs under solar irradiation. EPS were prone to flocculation under highly acidic conditions and minimal fluorescence of peaks was observed. The fluorophores in EPS were relatively stable under neutral and alkaline conditions. These findings are helpful for understanding the behavior of EPS in aquatic environments and their role in biogeochemical cycles of the elements. Copyright © 2015 Elsevier B.V. All rights reserved.
    No preview · Article · Feb 2015 · Colloids and surfaces B: Biointerfaces
  • [Show abstract] [Hide abstract]
    ABSTRACT: H2O2 is an emerging biocide for bloom-forming cyanobacteria. It is important to investigate the H2O2 scavenging ability of extracellular polymeric substances (EPS) of cyanobacteria because EPS with strong antioxidant activity may "waste" considerable amounts of H2O2 before it kills the cells. In this study, the buffering capacity against H2O2 of EPS from the bloom-forming cyanobacterium Microcystis aeruginosa was investigated. IC50 values for the ability of EPS and vitamin C (VC) to scavenge 50% of the initial H2O2 concentration were 0.097 and 0.28 mg mL(-1), respectively, indicating the higher H2O2 scavenging activity of EPS than VC. Both proteins and polysaccharides are significantly decomposed by H2O2 and the polysaccharides were more readily decomposed than proteins. H2O2 consumed by the EPS accounted for 50% of the total amount of H2O2 consumed by the cells. Cell growth and photosynthesis were reduced more for EPS-free cells than EPS coated cells when the cells were treated with 0.1 or 0.2 mg mL(-1) H2O2, and the maximum photochemical efficiency Fv/Fm of EPS coated cells recovered to higher values than EPS-free cells. Concentrations of H2O2 above 0.3 mg mL(-1) completely inhibited photosynthesis and no recovery was observed for both EPS-free and EPS coated cells. This shows that EPS has some buffering capacity against the killing effect of H2O2 on cyanobacterial cells. Such a strong H2O2 scavenging ability of EPS is not favorable for killing bloom-forming cyanobacteria. The high H2O2 scavenging capacity means considerable amounts of H2O2 have to be used to break through the EPS barrier before H2O2 exerts any killing effects on the cells. It is therefore necessary to determine the H2O2 scavenging capacity of the EPS of various bloom-forming cyanobacteria so that the cost-effective amount of H2O2 needed to be used for killing the cyanobacteria can be estimated. Copyright © 2014 Elsevier Ltd. All rights reserved.
    No preview · Article · Nov 2014 · Water Research
  • Source
    Chunnuan Deng · Hua Shao · Xiangliang Pan · Shuzhi Wang · Daoyong Zhang
    [Show abstract] [Hide abstract]
    ABSTRACT: The herbicidal effects of harmaline extracted from Peganum harmala seed on cell growth and photosynthesis of green algae Chlorella pyrenoidosa were investigated using chlorophyll a fluorescence and thermoluminescence techniques. Exposure to harmaline inhibited cell growth, pigments contents and oxygen evolution of C. pyrenoidosa. Oxygen evolution was more sensitive to harmaline toxicity than cell growth or the whole photosystem II (PSII) activity, maybe it was the first target site of harmaline. The JIP-test parameters showed that harmaline inhibited the donor side of PSII. Harmaline decreased photochemical efficiency and electron transport flow of PSII but increased the energy dissipation. The charge recombination was also affected by harmaline. Amplitude of the fast phase decreased and the slow phase increased at the highest level of harmaline. Electron transfer from QA(-) to QB was inhibited and backward electron transport flow from QA(-) to oxygen evolution complex was enhanced at 10μgmL(-1) harmaline. Exposure to 10μgmL(-1) harmaline caused appearance of C band in thermoluminescence. Exposure to 5μgmL(-1) harmaline inhibited the formation of proton gradient. The highest concentration of harmaline treatment inhibited S3QB(-) charge recombination but promoted formation of QA(-)YD(+) charge pairs. P. harmala harmaline may be a promising herbicide because of its inhibition of cell growth, pigments synthesis, oxygen evolution and PSII activities.
    Full-text · Article · Oct 2014 · Pesticide Biochemistry and Physiology
  • Daoyong Zhang · Duu-Jong Lee · Xiangliang Pan
    [Show abstract] [Hide abstract]
    ABSTRACT: Urumqi City is the farthest metropolis from an ocean in the world. This communication measured the concentrations of eight potentially harmful metals Cr, Pb, Hg, Ni, Cd, Zn, Cu, and Sr and metalloids As and Sb in the street dusts collected from Urumqi City and compared them with those noted in Taipei City. Although the geological environments of Taipei and Urumqi differ markedly; however, the potential harmful metals and metalloids studied are surprisingly similar in their distributions in these two cities. Particularly, As is a common pollutant that poses severe health risks to residents in both cities. Hence, the anthropogenic rather than geogenic factors pre-dominate the formation and distributions of street dusts. This finding suggests common control strategy may be applicable to different metropolis on the confinement of adverse health effects by the street dusts.
    No preview · Article · Sep 2014 · Journal of the Taiwan Institute of Chemical Engineers
  • Chunnuan Deng · Xiangliang Pan · Daoyong Zhang
    [Show abstract] [Hide abstract]
    ABSTRACT: Pollution with antibiotics poses a great risk to aquatic ecosystems. Although some toxic effects of antibiotics on photosystem II (PSII) have been documented, their toxicity to photosystem I (PSI) is still unclear. In this study, effects of ofloxacin on activities of both PSI and PSII of Microcystis aeruginosa (Kützing) Kützing were investigated. Exposure to 0.1 mg L−1 ofloxacin led to increases in contents of chlorophyll a and carotenoids and photosynthetic activity of M. aeruginosa. PSI activity and its electron transport were not affected by 0.1 mg L−1 ofloxacin. When M. aeruginosa was exposed to ≥10 mg L−1 ofloxacin, the electron transport rates of PSI and PSII, the yield of cyclic electron flow (CEF) and the contribution of linear electron flow (LEF) to PSI decreased whereas Y(NA) (limitation of donor side of PSI) and Y(NO) (the quantum yield of non-regulated energy dissipation in PSII) significantly increased. CEF had a significant contribution to alleviating the inhibitory effect of ofloxacin on PSI of M. aeruginosa treated with low concentrations of ofloxacin. The protective role CEF for tolerance of PSI to the toxicity of ofloxacin decreased with increasing ofloxacin concentration.
    No preview · Article · Sep 2014 · Journal of Bioscience and Bioengineering
  • Source
    Shuzhi Wang · Xiangliang Pan · Daoyong Zhang
    [Show abstract] [Hide abstract]
    ABSTRACT: The knowledge of the effects of Sb(V) on the physiological characteristics of cyanobacteria was still limited. In the present study, responses of photosystem I and II (PSI and PSII), cyclic electron flow (CEF), and interphotosystem electron transport of Microcystis aeruginosa to 5–100 mg/l Sb(V) were synchronously measured using the Dual-PAM-100. 5 mg/l Sb (V) significantly inhibited PSII activity, but had no significant effects on PSI activity. At higher concentrations of Sb(V), the quantum yield and electron transport of PSI were less affected compared to PSII. The ratio of Y(II)/Y(I) significantly decreased with increasing Sb(V) concentration. It decreased from 0.7 for control to 0.4 for 100 mg/l Sb(V)-treated cells, indicating that the change of the distribution of quantum yields between two photosystems and more serious inhibition of PSII under stress of Sb(V) compared to PSI. CEF was activated associated with the inhibition of linear electron flow after exposure to Sb(V). The contribution of Y(CEF) to the quantum yield and activity of PSI increased with increasing Sb(V) concentrations. The cyclic electron transport rate made a significant contribution to electron transport rate of PSI, especially at high Sb(V) concentration (100 mg/l) and high illumination (above 555 μmol photons/m2/s). The stimulation of CEF was essential for the higher tolerance of PSI than PSII to Sb(V).
    Full-text · Article · Aug 2014 · Current Microbiology
  • Daoyong Zhang · Xiangliang Pan · Duu-Jong Lee
    [Show abstract] [Hide abstract]
    ABSTRACT: In total, 34 urban street dust samples were collected in Taipei City. Concentrations of potential harmful metals Cr, Pb, Hg, Ni, Cd, Zn, Cu, and Sr and metalloids As and Sb in street dust samples were measured and their sources and potential health risks to humans were evaluated. Traffic emissions were the main source of the potential harmful metals and metalloids in street dust samples from Taipei. Exposure routes for all studied potential harmful metals and metalloids, except for that of Hg, follow ingestion > dermal contact > inhalation. Children are at higher health risk than adults. The As, Sb, Cr, and Pb concentrations in Taipei have adverse non-cancer health effects on residential children. Carcinogenic risk of As exposure for children and adults in Taipei were higher than the threshold value (10−6–10−4). The study highlights the determinant role of anthropogenic factors in the formation of street dust.
    No preview · Article · Jul 2014 · Journal of the Taiwan Institute of Chemical Engineers
  • Source
    Chunnuan Deng · Xiangliang Pan · Shuzhi Wang · Daoyong Zhang
    [Show abstract] [Hide abstract]
    ABSTRACT: Responses of photosystem I and II activities of Microcystis aeruginosa to various concentrations of Cu(2+) were simultaneously examined using a Dual-PAM-100 fluorometer. Cell growth and contents of chlorophyll a were significantly inhibited by Cu(2+). Photosystem II activity [Y(II)] and electron transport [rETRmax(II)] were significantly altered by Cu(2+). The quantum yield of photosystem II [Y(II)] decreased by 29 % at 100 μg L(-1) Cu(2+) compared to control. On the contrary, photosystem I was stable under Cu(2+) stress and showed an obvious increase of quantum yield [Y(I)] and electron transport [rETRmax(I)] due to activation of cyclic electron flow (CEF). Yield of cyclic electron flow [Y(CEF)] was enhanced by 17 % at 100 μg L(-1) Cu(2+) compared to control. The contribution of linear electron flow to photosystem I [Y(II)/Y(I)] decreased with increasing Cu(2+) concentration. Yield of cyclic electron flow [Y(CEF)] was negatively correlated with the maximal photosystem II photochemical efficiency (F v/F m). In summary, photosystem II was the major target sites of toxicity of Cu(2+), while photosystem I activity was enhanced under Cu(2+) stress.
    Full-text · Article · Jun 2014 · Biological Trace Element Research
  • Wen Juan Song · Xiangliang Pan · Daoyong Zhang
    [Show abstract] [Hide abstract]
    ABSTRACT: Extracellular polymeric substances (EPS) are important components of activated sludge and play an important role in removing heavy metals. The interaction of soluble EPS (SEPS)/bound EPS (BEPS) with Pb(II) was investigated using excitation—emission matrix (EEM) fluorescence spectroscopy and infra-red spectrometry. One protein-like fluorescence peak (peak A) was identified from the EEM spectra of SEPS and BEPS, and one aromatic protein peak (peak B) was observed in the EEM spectra of SEPS. the interaction of Pb(II) with SEPS was governed by collision sorption, while the binding of Pb(II) to BEPS was due to complexation. Functional groups of proteins, polysaccharides, lipids, and uronic acid were involved in Pb(II) adsorption to SEPS/BEPS. The organic acids in SEPS are also responsible for binding Pb(II) to SEPS. Other groups such as the phosphate group in the fingerprint zone also participated in binding of Pb(II) to EPS. There were no significant differences in the values of binding constants and conditional stability constants between SEPS and BEPS.
    No preview · Article · Apr 2014 · Biotechnology & Biotechnological Equipment
  • Ying Liu · Shuyong Mu · Anming Bao · Daoyong Zhang · Xiangliang Pan
    [Show abstract] [Hide abstract]
    ABSTRACT: Bosten Lake, the largest inland lake in China, has been contaminated with arsenic (As) due to anthropogenic activities. Salinity of the lake water has been increasing due to the extremely dry climate and salt drainage from the farmland. Effects of the increasing salinity on the geochemical behavior of arsenic in sediment are still unclear. In this study, vertical variation of geochemical fractions of As in sediment and arsenic concentration in porewater along the salinity gradient of Bosten Lake was studied. Effects of salinity and ions and anions in porewater on arsenic concentration were also examined. Arsenic content in the five Tessier fractions followed the decreasing order of residual ≫ exchangeable > Fe and Mn oxides > organic > carbonate. The ecological risk of arsenic in the sediment was at low or medium levels, indicated by the low percentage of exchangeable and carbonate bound fractions. Contrary to the decreasing electrical conductivity of porewater with depth, arsenic concentration in porewater showed an increasing trend with depth. Arsenic concentration in porewater increased from around zero at the surface layer of sediment to over 600 μg L−1 in deeper layers of some sites. Arsenic concentration inversely correlated with electrical conductivity in porewater. Arsenic concentration generally decreased with increasing concentrations of SO4 2−, Ca2+, Mg2+ and Na+ but showed no clear relation with concentrations of K+ and Cl−. This study implies that increase of salinity may decrease the release of arsenic from sediment and its ecological risk.
    No preview · Article · Apr 2014 · Environmental Earth Sciences
  • Baohua Li · Changyan Tian · Daoyong Zhang · Xiangliang Pan
    [Show abstract] [Hide abstract]
    ABSTRACT: Anaerobic Fe(II) Oxidizing Denitrifiers (AFODN), a type of newly found Fe(II)-oxidizing bacteria, play an important role in iron and nitrogen cycling. In the present study, a novel AFODN strain PXL1 was isolated from anaerobic activated sludge. Phylogenetic analysis of 16S rRNA gene sequence revealed similarity between this strain and Citrobactor freundii. The strain reduced 30% of nitrate and oxidized 85% of Fe(II) over 72 h with an initial Fe(II) concentration of 3.4 mM and nitrate concentration of 9.5 mM. Oxidation of iron was dependent on the reduction of nitrate to nitrite in the absence of other electron donors or acceptors. Nitrate reduction and Fe(II) oxidation followed first-order reaction kinetics. Iron oxides accumulated in the culture were analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). The strain recovered deposited oxidized Fe in the form of amorphous Fe oxides.
    No preview · Article · Feb 2014 · Geomicrobiology
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study characterized the interactions of goethite, EPS from cyanobacterium Chroococcus sp. and Hg(II) using excitation emission matrix (EEM) spectra and adsorption isotherms. Three protein-like fluorescence peaks were noted to quench in the presence of Hg(II). The estimated conditional stability constant (logKa) and the binding constant (logKb) of the studied EPS-Hg(II) systems ranged 3.84-4.24 and 6.99-7.69, respectively. The proteins in EPS formed stable complex with Hg(II). The presence of proteins of Chroococcus sp. enhanced the adsorption capacity of Hg(II) on goethite; therefore, the goethite-EPS soil is a larger Hg(II) sink than goethite alone soil. Biosorption significantly affects the mobility of Hg(II) in goethite soils.
    Full-text · Article · Dec 2013 · Bioresource Technology

Publication Stats

700 Citations
150.28 Total Impact Points

Top co-authors View all

Institutions

  • 2007-2015
    • Chinese Academy of Sciences
      • • State Key Laboratory of Environmental Geochemistry
      • • Institute of Geochemistry
      Peping, Beijing, China
    • Tsinghua University
      • Institute of Nuclear and New Energy Technology
      Peping, Beijing, China
  • 2011-2014
    • National Taiwan University
      • Department of Chemical Engineering
      T’ai-pei, Taipei, Taiwan
  • 2013
    • National Taiwan University of Science and Technology
      • Department of Chemical Engineering
      T’ai-pei, Taipei, Taiwan