A bio-generated Fe(iii)-binding exopolysaccharide used as new catalyst for phenol hydroxylation

Baldi, Franco; Marchetto, Davide; Zanchettin, Davide; Sartorato, Elisabetta; Paganelli, Stefano; Piccolo, Oreste

doi:10.1039/c004967k

Cited by 20 publications

(9 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Colanic acid structures are different and are present in many Gram-negative bacteria (Chen et al, 1987;Withfield, 2006), but this analogue is special because it binds to many metals (Arčon et al, 2012) as a result of environmental adaptation typical of acid mine drainage. To date, only monometallic EPS have been bio-generated (Baldi et al, 2010(Baldi et al, , 2011Paganelli et al, 2013). In this study we produced for the first time two bi-metallic EPS species in order to obtain more biomaterials from the microbial cultures.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

XAS analysis of iron and palladium bonded to a polysaccharide produced anaerobically by a strain ofKlebsiella oxytoca

Arčon

Paganelli

Piccolo

et al. 2015

J Synchrotron Radiat

Self Cite

View full text Add to dashboard Cite

Klebsiella oxytoca BAS-10 ferments citrate to acetic acid and CO2, and secretes a specific exopolysaccharide (EPS), which is able to bind different metallic species. These biomaterials may be used for different biotechnological purposes, including applications as innovative green biogenerated catalysts. In production of biogenerated Pd species, the Fe(III) as ferric citrate is added to anaerobic culture of K. oxytoca BAS-10, in the presence of palladium species, to increase the EPS secretion and improve Pd-EPS yield. In this process, bi-metallic (FePd-EPS) biomaterials were produced for the first time. The morphology of bi-metallic EPS, and the chemical state of the two metals in the FePd-EPS, are investigated by transmission electron microscopy, Fourier transform infra-red spectroscopy, micro-X-ray fluorescence, and X-ray absorption spectroscopy methods (XANES and EXAFS), and compared with mono-metallic Pd-EPS and Fe-EPS complexes. Iron in FePd-EPS is in the mineralized form of iron oxides/hydroxides, predominantly in the form of Fe(3+), with a small amount of Fe(2+) in the structure, most probably a mixture of different nano-crystalline iron oxides and hydroxides, as in mono-metallic Fe-EPS. Palladium is found as Pd(0) in the form of metallic nanoparticles with face-centred cubic structure in both bi-metallic (FePd-EPS) and mono-metallic (Pd-EPS) species. In bi-metallic species, Pd and Fe nanoparticles agglomerate in larger clusters, but they remain spatially separated. The catalytic ability of bi-metallic species (FePd-EPS) in a hydrodechlorination reaction is improved in comparison with mono-metallic Pd-EPS.

show abstract

Section: Discussionmentioning

confidence: 99%

“…EPS binds iron and other metals during the bacterial growth. To date, only monometallic EPS have been biosynthetized (Baldi et al, 2010(Baldi et al, , 2011. In this study we produced for the first time two bimetallic species FePd-EPS(A) and FePd-EPS(B) in order to obtain more biomaterials from the microbial cultures.…”

Section: Elemental Analysis and Temmentioning

confidence: 99%

XAS analysis of iron and palladium bonded to a polysaccharide produced anaerobically by a strain ofKlebsiella oxytoca

Arčon

Paganelli

Piccolo

et al. 2015

J Synchrotron Radiat

Self Cite

View full text Add to dashboard Cite

show abstract

“…Details Fe(III) citrate fermentation process and EPS structure could be found elsewhere [28]. At stationary phase, the strain produces a ferric exopolymeric hydrogel with entrapped Fe NPs [32], similar to ferric hydroxides in ferritin [33]. FeEPS was extracted by the bacterial culture and precipitated using 70% ethanol solution at 4°C.…”

Section: Production Of Biogenerated Feepsmentioning

confidence: 99%

“…In our experiments alcoholic fraction was removed by washing with MilliQ water. Fe NPs embedded in the EPS gel were 9-15 nm [32,33] with +2.82 average Fe valence [33]. FeEPS powder was produced by drying the gel in oven at 30°C.…”

Section: Production Of Biogenerated Feepsmentioning

confidence: 99%

Arsenate and arsenite removal from contaminated water by iron oxides nanoparticles formed inside a bacterial exopolysaccharide

Casentini

Gallo

Baldi

2019

Journal of Environmental Chemical Engineering

Self Cite

View full text Add to dashboard Cite

In the last decades, the presence of high As levels in groundwaters poses a serious limitation to the use of this resources for drinking purposes in several parts of the world. Treatment of As-rich waters selected iron oxides filters as more effective, low cost and selective technology. Green and biologically-driven pathways to synthetize new nanostructured iron oxy-hydroxides are becoming always more attractive. We tested the suitability of FeOOH nanoparticles (9-15 nm) produced by Klebsiella oxytoca strain DSM 29614 and encapsulated in EPS gel structure to treat arsenic rich water. Different gel:water volume ratios were tested to treat 5000 μg As/L solution. 20% FeEPS solution was able to remove 95% of As(V) while in 5% solution removal was reduced to 60%. Arsenic adsorption was very fast and follows pseudo-2 nd order kinetic with maximum adsorption capacity reached at about 30 min. Adsorption followed Langmuir model for As(V) with q max = 31.8 mg As /g Fe and BET for As(III) with 8 mg As /g Fe for the first layer in 10% FeEPS solution. FeEPS dried into powder showed noticeable removal only after 2 h, hence not suitable for drinking water treatment. Treatment of natural As levels in mimicked groundwaters showed 87-95% As(V) and 45-61% As(III) removal after 5 min. FeEPS gel immobilized onto bivalve shell debris was used in packed-bed filters. It retained 49.8 mg As /g Fe from 150 μg/L As(V) spiked groundwater before reaching breakthrough at 8000 BVs. Biologically produced FeEPS gel showed good potentialities as eco-friendly material to remove As from contaminated groundwater.

show abstract

“…Since bacterial cells may often synthesize and secret polysaccharides [16], recently we envisaged a new way of using bacteria to produce carbohydrates able to bind metals during their growing in the presence of suitable metal salts. In particular Klebsiella oxytoca DSM 29614 (ex strain BAS-10) strain, isolated from the acid mine drainage of pyrite mines and able to produce a peculiar exopolysaccharide (EPS), constituted by a branched heptameric repeating structure [17], was investigated with success by some of us to generate some metal-polysaccharide catalysts [18,19]. In this study, a new bio-generated Rh based catalyst (Rh-EPS) was produced in order to determine its activity and selectivity in the aqueous biphasic hydroformylation of some olefins chosen as model substrates.…”

Section: Introductionmentioning

confidence: 99%

A new biogenerated Rh-based catalyst for aqueous biphasic hydroformylation

Paganelli

Piccolo²,

Baldi

et al. 2015

Catalysis Communications

Self Cite

View full text Add to dashboard Cite

A new bio-generated rhodium based system embedded in a peculiar polysaccharide matrix (Rh-EPS), was obtained and purified from cultures of bacterial cells of Klebsiella oxytoca DSM 29614. The product was analyzed with different techniques to obtain information on its structure-property correlation. In order to determine its catalytic activity and selectivity in the aqueous biphasic hydroformylation some olefins were chosen as model substrates, obtaining fine-good results.

show abstract

A bio-generated Fe(iii)-binding exopolysaccharide used as new catalyst for phenol hydroxylation

Cited by 20 publications

References 21 publications

XAS analysis of iron and palladium bonded to a polysaccharide produced anaerobically by a strain ofKlebsiella oxytoca

XAS analysis of iron and palladium bonded to a polysaccharide produced anaerobically by a strain ofKlebsiella oxytoca

Arsenate and arsenite removal from contaminated water by iron oxides nanoparticles formed inside a bacterial exopolysaccharide

A new biogenerated Rh-based catalyst for aqueous biphasic hydroformylation

Contact Info

Product

Resources

About