Role of microbial exopolymeric substances (EPS) on chromium sorption and transport in heterogeneous subsurface soils: I. Cr(III) complexation with EPS in aqueous solution

Kantar, Çetin; Demiray, Hilal; Doğan, Nazime Mercan; Dodge, Cleveland J.

doi:10.1016/j.chemosphere.2011.01.009

Cited by 60 publications

(25 citation statements)

References 31 publications

(72 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Surprisingly the results demonstrated that Cr(VI) adsorption was kept consistent even with change in temperature (Figure. 7B), which was different to other adsorbents [31].…”

Section: Resultsmentioning

confidence: 56%

Optimization of Fermentation Conditions and Properties of an Exopolysaccharide from Klebsiella sp. H-207 and Application in Adsorption of Hexavalent Chromium

Han

et al. 2013

PLoS ONE

View full text Add to dashboard Cite

The novel exopolysaccharide HZ-7 is produced by Klebsiella sp. H-207, and its fermentation conditions were optimized by response surface methodology (RSM). In this study, the optimized medium consisted of sucrose 31.93 g/L, KNO3 2.17 g/L and K2HPO4 5.47 g/L; while the optimized culture conditions consisted of seed age 13 h, with an inoculum size of 10.6% and incubation temperature of 28.9°C. A maximum HZ-7 yield of about 15.05 g/L was achieved under the optimized conditions using RSM and single-factor experiments. Next the exopolysaccharide HZ-7 was partially purified and characterized. The resulting product showed good properties, such as high concentration of uronic acid (41.67%), low average molecular weight (about 1.94×105 Da) and porous surface structure, were very advantageous to biosorption. Therefore HZ-7 was applied to absorb hexavalent chromium (Cr(VI)). The maximum adsorption efficiency (99.2%) which was obtained at an initial pH of 1.0 along with an initial Cr(VI) concentration of 20 mg/L, was not affected by ordinary metal ions and temperature. These data suggest Klebsiella sp. H-207 exopolysaccharide will be promising potential for industrial application.

show abstract

“…Surprisingly the results demonstrated that Cr(VI) adsorption was kept consistent even with change in temperature (Figure. 7B), which was different to other adsorbents [31].…”

Section: Resultsmentioning

confidence: 56%

Optimization of Fermentation Conditions and Properties of an Exopolysaccharide from Klebsiella sp. H-207 and Application in Adsorption of Hexavalent Chromium

Han

et al. 2013

PLoS ONE

View full text Add to dashboard Cite

show abstract

“…He et al [40] found that more Cr was removed when large amounts of EPS were produced and suggested that the EPS contributed to the Cr(VI) removal. Cr(III) binds with EPS through phosphate groups have also been reported by Kantar et al [41] and Dogan et al [15]. Therefore, the rapid reduction process from Cr(VI) to Cr(III) in the unsaturated P. saccharolyticum LY10 biofilms might be related to the large amounts of EPS and the Cr(VI)-reducing substances available in the EPS of the biofilms, which needs to be further studied.…”

Section: Analysis Of Cr Speciation In the Biofilms By Xasmentioning

confidence: 66%

“…Due to the low water solubility and high stability of metal phosphates, forming phosphate precipitation is an effective way for microorganisms to accumulate or remove heavy metals from the environment [44]. However, Kantar et al [41] found that the binding of Cr(III) with EPS through phosphate groups enhanced the solubility of Cr(III) species. P. putida cells could remove Cd from the environment by forming polyphosphate particles containing cadmium [45].…”

Section: Analysis Of Cr Speciation In the Biofilms By Xasmentioning

confidence: 98%

Determination of the accumulation, spatial distribution and reduction of Cr in unsaturated Pseudochrobactrum saccharolyticum LY10 biofilms by X-ray fluorescence and absorption methods

Long

Zou

Hashmi

et al. 2015

Chemical Engineering Journal

View full text Add to dashboard Cite

“…This current work provides further data on the role of bacterial EPS on Cr(VI) reduction and defense mechanisms that Pseudomonas bacteria develop to cope with the toxic effect of Cr(III) and Cr(VI) on microbial cells. In our previous work, we found that Cr(III) strongly complexes with microbial EPS released by bacteria during microbial Cr(VI) reduction :

Organic acids + Cr (VI) \overset{Cells / Enzymes}{true⟶} Cr (III) + EPS \to Cr (III) - EPS

…”

Section: Discussionmentioning

confidence: 99%

Effect of Chromium and Organic Acids on Microbial Growth and Exopolymeric Substance Production by Pseudomonas Bacteria

Doğan

Kantar

Doğan

2013

CLEAN Soil Air Water

Self Cite

View full text Add to dashboard Cite

Natural organic acids are capable of stimulating microbial chromium(VI) reduction, but little information is available about their behavior on microbial growth, exopolymeric substance (EPS) production, and subsequent microbial Cr(VI) reduction. Here, laboratory batch experiments were conducted to determine the effects of different natural organic acids (galacturonic, glucuronic, citric, and alginic acid) on microbial EPS production and the growth rates of four different naturally occurring soil bacteria (Pseudomonas putida P18, P. aeruginosa P16, P. fluorescens ATCC 55241, and P. stutzeri P40) as a function of pH and time in solutions containing toxic metal ions such as Cr(III) and Cr(VI). While the addition of Cr(VI) led to a negative impact on microbial growth in all strains studied, Cr(VI) significantly enhanced EPS release from cells due to extreme cell lysis. Organic acids diminished the toxic effects of Cr(VI) on cells, and thus significantly increased microbial cell growth and the EPS yield. The addition of Cr(III) with Cr(VI), on the other hand, led to a significant decrease in microbial cell growth rates relative to the systems containing only Cr(VI). This toxic effect decreased significantly in the presence of organic acids, and thus the EPS yield increased due to the formation of less toxic Cr(III)‐EPS species. The overall results indicate that while the accumulation of free Cr(III) ion in aqueous phase during microbial Cr(VI) reduction may have an adverse influence on microbial cell growth, the EPS released by bacteria may bind with free Cr(III) ion in solution, and thus increase the cell growth rate due to the removal of toxic products of microbial reduction.

show abstract

Role of microbial exopolymeric substances (EPS) on chromium sorption and transport in heterogeneous subsurface soils: I. Cr(III) complexation with EPS in aqueous solution

Cited by 60 publications

References 31 publications

Optimization of Fermentation Conditions and Properties of an Exopolysaccharide from Klebsiella sp. H-207 and Application in Adsorption of Hexavalent Chromium

Optimization of Fermentation Conditions and Properties of an Exopolysaccharide from Klebsiella sp. H-207 and Application in Adsorption of Hexavalent Chromium

Determination of the accumulation, spatial distribution and reduction of Cr in unsaturated Pseudochrobactrum saccharolyticum LY10 biofilms by X-ray fluorescence and absorption methods

Effect of Chromium and Organic Acids on Microbial Growth and Exopolymeric Substance Production by Pseudomonas Bacteria

Contact Info

Product

Resources

About