Good afternoon,

This week Dr. Sebastià Puig have assisted to the Bacterial Electron Transfer Processes and their Regulation meeting at Porto Novo Beach, Vimeiro (Portugal). The meeting was organized by the European Federation of Biotechnology Microbial Physiology Section. The meeting had 10 sessions that include a total of approximately 30 oral lectures and around 30 poster presentations. http://www.efb-central.org/Bacterial_electron_transfer/docs/Programme1.pdf

He was proud to present our advances on denitrifying bioelectrochemical systems. This study is part of the PhD thesis of Narcis Pous. We are actively collaborating with the INRA-Narbonne (France), UFZ-Leizip (Germany) and University of Queensland (Australia).

More information:

• Pous, N., Koch, C., Harnisch, F., Carmona, A., Virdis, B., Balaguer, M.D, Colprim, J. and Puig, S. Denitrifying bioelectrochemical systems: from fundamentals to water applications. Bacterial Electron Transfer Processes and their Regulation Meeting. 15-18th March, Vimeiro (Portugal).

If you are interested, please feel free to write us.

Microbiome characterisation of MFCs used for the treatment of swine manure

Microbiome characterisation of MFCs used for the treatment of swine manure

The paper entitled "Microbiome characterisation of MFCs used for the treatment of swine manure" has been accepted for publication in the Journal of Hazardous Materials

The study was carried out by Anna Vilajeliu-Pons, Sebastià Puig, Narcís Pous, Inmaculada Salcedo-Dávila, Lluís Bañeras, M. Dolors Balaguer and Jesús Colprim.

ABSTRACT

Conventional swine manure treatment is performed by anaerobic digestion, but nitrogen is not treated. Microbial Fuel Cells (MFCs) allow organic matter and nitrogen removal with concomitant electricity production. MFC microbiomes treating industrial wastewaters as swine manure have not been characterized. In this study a multidisciplinary approach allowed microbiome relation with nutrient removal capacity and electricity production. Two different MFC configurations (C-1 and C-2) were used to treat swine manure. In C-1, the nitrification and denitrification processes took place in different compartments, while in C-2, simultaneous nitrification-denitrification occurred in the cathode. Clostridium disporicum and Geobacter sulfurreducens were identified in the anode compartments of both systems. C. disporicum was related to the degradation of complex organic matter compounds and G. sulfurreducens to electricity production. Different nitrifying bacteria populations were identified in both systems because of the different operational conditions. The highest microbial diversity was detected in cathode compartments of both configurations, including members of Bacteroidetes, Chloroflexiaceae and Proteobacteria. These communities allowed similar removal rates of organic matter (2.02-2.09 kg COD m-3 d-1) and nitrogen (0.11- 0.16 kg N m-3 d-1) in both systems. However, they differed in the generation of electric energy (20 and 2 mW m-3 in C-1 and C-2, respectively).

If you are interested on the full paper, its doi code is 10.1016/j.jhazmat.2015.02.014

Continuous acetate production through microbial electrosynthesis from CO2 with microbial mixed culture

Our paper entitled "Continuous acetate production through microbial electrosynthesis from CO2 with microbial mixed culture" has been accepted for publication in the Journal of chemical technology and biotechnology

The study was carried out by Pau Batlle-Vilanova, Sebastià Puig, Rafael Gonzalez-Olmos, M. Dolors Balaguer, and Jesús Colprim

ABSTRACT
BACKGROUND: Microbial electrosynthesis represents a promising approach for renewable energy storage in which chemically stable compounds are produced using CO2 as feedstock. This report aims the continuous production of acetate through microbial electrosynthesis from CO2 and assesses how the production rates could be increased. 
RESULTS: A continuous acetate production rate of 0.98 mmol C·LNCC -1·d-1 was obtained using CO2 as feedstock and with a pH control around 5.8. This conditions increased substrate availability and favoured microbial electrosynthesis. Cyclic voltammograms demonstrated the electroautotrophic activity on the biocathode surface, which increased due to the pH control and caused current demand and acetate production rate to exponentially rise up. 
CONCLUSION: The pH decrease was shown as an effective strategy to increase substrate availability and enhance microbial electrosynthesis. By making microbial electrosynthesis a feasible technology, CO2 could become an alternative feedstock for the carboxylate platform.

If you are interested on the full paper, its doi code is 10.1002/jctb.4657

New paper: Microbial electrosynthesis of butyrate from carbon dioxide

good morning,

yesterday our paper "Microbial electrosynthesis of butyrate from carbon dioxide" was accepted for publication in Chemical Communications. 

In this paper we proves for the 1st time the production of butyrate from carbon dioxide.Neither hydrogen or carbon monoxide were dosed.

Interested?

Ganigué, R., Puig, S., Batlle-Vilanova, P., Balaguer, M.D. and Colprim, J. 2015. Microbial electrosynthesis of butyrate from carbon dioxide. Chem. Commun. doi: 10.1039/C4CC10121A.

Cathode potential and anode electron donor evaluation for a suitable treatment of nitrate-contaminated groundwater in bioelectrochemical systems

Our research for improving the bioremediation of nitrate-polluted groundwater using bioelectrochemical systems has allowed us to publish the article Cathode potential and anode electron donor evaluation for a suitable treatment of nitrate-contaminated groundwater in bioelectrochemical systems in the journal Chemical Engineering Journal.

The work has been carried out by Narcis Pous, Sebastià Puig, M. Dolors Balaguer and Jesús Colprim.

In this article we demonstrated that nitrate-polluted groundwater can be succesfully treated in a bioelectrochemical system without requirements of organic matter and a competitive cost.

The abstract is:

"Several regions around the world present high levels of nitrate in groundwater. Due to its toxicity, nitrate must be removed before the groundwater is used as drinking- water. This study assessed how a denitrifying bioelectrochemical system could be operated to treat nitrate- polluted groundwater. It evaluated the cathode potential (from +597 to -703 mV vs SHE) and the anode electron donor (acetate and water). Similar trends were found regardless of the anode electron donor. The nitrate removal rate increased from 1.05 to 5.44 mgN-NO3-·LNCC-1·h-1 when the cathode potential was lowered from +597 to -403 mV vs SHE, where it stabilized. The nitrate reduction end- products (nitrite, nitrous oxide and dinitrogen gas) also changed with the different potentials of the cathode electrode. The World Health Organization nitrates and nitrites standards for drinking- water were reached at cathode potentials between -103 and -203 mV vs SHE. The highest rate of nitrate conversion to N2 (2.59 mgN-NO3-·LNCC-1·h-1, 93.9%) occurred at -123 mV using water as anode electron donor, with an estimated operational cost similar to conventional technologies (0.68·10-2 kWh·gN-NO3-removed-1). The long-term stability of proposed operation was demonstrated during 96 days, and the rate of
nitrate conversion to N2 even increased to 4.09 mgN-NO3-·LNCC-1·h-1. A carbon- free operation for a bioelectrochemical system has been developed to treat nitrate- polluted groundwater at a competitive cost."

The DOI code is: 10.1016/j.cej.2014.11.002.

Extracellular electron transfer of biocathodes: Revealing the potentials for nitrate and nitrite reduction of denitrifying microbiomes dominated by Thiobacillus sp.

From February to May 2014, Narcís Pous carried out a research stay at the laboratory of Dr. Falk Harnisch (UFZ (Leipzig, Germany)). 

This fruitful collaboration has allowed us to publish the article Extracellular electron transfer of biocathodes: Revealing the potentials for nitrate and nitrite reduction of denitrifying microbiomes dominated by Thiobacillus sp.  in the journal Electrochemistry Communications. 

The work has been carried out by Narcis Pous, Christin Koch, Jesús Colprim, Sebastià Puig and Falk Harnisch.

In this article we were able to show the respective reduction potentials for nitrate and nitrite in a Thiobacillus sp. enriched biocathode. This finding will clearly contribute to the engineering (start-up and operation) of denitrifying bioelectrochemical systems.

The abstract is:

"The use of biocathodes in bioelectrochemical systems (BES) for the removal of nitrate

in wastewater has become a vital field of research. However, the elucidation of the

underlying extracellular electron transfer (EET) fundamentals of denitrifying

biocathodes is still lacking, but required for a deeper BES understanding and

engineering. This study reports for the first time on the thermodynamics of microbial

cathodes for nitrate and nitrite reductions using microbial microcosms isolated from a

running denitrifying BES. Cyclic voltammetry showed that nitrate and nitrite reduction

proceed at -0.30V, and -0.70V vs. Ag/AgCl, respectively, by surface associated EET

sites. The biocathodes were predominantly covered by Thiobacillus sp. contributing

with a nitrate reductase (narG) to the major function of the microscosms. In conclusion,

the EET characteristics of denitrifying biocathodes are demonstrated for the first time."

The collaboration with Dr. Harnisch have been a pleasure for us, and we hope to continue collaborating close together!

Anaerobic arsenite oxidation with an electrode serving as the soleelectron acceptor: A novel approach to the bioremediation of arsenic-polluted groundwater

From October to December 2013, Narcís Pous carried out a research stay at the laboratory of Dr. Federico Aulenta (IRSA-CNR (Monterotondo, Italy)).

As a result, the study entitled Anaerobic arsenite oxidation with an electrode serving as the sole electron acceptor: A novel approach to the bioremediation ofarsenic-polluted groundwater has been accepted for publication at the Journal of Hazardous Materials.

The work has been carried out by Narcis Pous, Barbara Casentini, Simona Rossetti, Stefano Fazi, Sebastià Puig and Federico Aulenta.

This study demonstrate, for the first time, that anaerobic oxidation of arsenite can be carried out by bacteria able to use a polarized electrode as electron acceptor.

The abstract is:

"Arsenic contamination of soil and groundwater is a serious problem worldwide. Here we show that anaerobic oxidation of As(III) to As(V), a form which is more extensively and stably adsorbed onto metal-oxides, can be achieved by using a polarized (+497 mV vs. SHE) graphite anode serving as terminal electronacceptor in the microbial metabolism. The characterization of the microbial populations at the electrode,by using in situ detection methods, revealed the predominance of gammaproteobacteria. In principle,the proposed bioelectrochemical oxidation process would make it possible to provide As(III)-oxidizing microorganisms with a virtually unlimited, low-cost and low-maintenance electron acceptor as well aswith a physical support for microbial attachment."

It has been a pleasure for us to work with Dr. Aulenta, and we hope that this collaboration can be the first step for future works!