An overview on emerging bioelectrochemical systems (BESs): Technology for sustainable electricity, waste remediation, resource recovery, chemical production and beyond
Bajracharya, S. ; Sharma, M. ; Mohanakrishna, Gunda ; Benneton, Xochitl Dominguez ; Strik, D.P.B.T.B. ; Sarma, Priyangshu M. ; Pant, Deepak - \ 2016
Renewable Energy 98 (2016). - ISSN 0960-1481 - p. 153 - 170.
Recalcitrant removal - Microbial electrocatalysis - CO2 sequestration - Biosensors - Value-added chemicals production
Bioelectrochemical systems (BESs) are unique systems capable of converting chemical energy into electrical energy (and vice-versa) while employing microbes as catalysts. Such organic wastes including low-strength wastewaters and lignocellulosic biomass were converted into electricity with microbial fuel cells (MFCs). Likewise, electrical energy was used to produce hydrogen in microbial electrolysis cells (MECs) or other products including caustic and peroxide. BES were also designed to recover nutrients, metals or removal of recalcitrant compounds. Moreover, photosynthetic micro-organisms as well as higher plants were implemented to use solar energy for electricity generation. The diversity on microbial and enzymatic catalysts offered by nature allows a plurality of potential applications. As compared to conventional fuel cells, BESs operate under relatively mild conditions and do not use expensive precious metals as catalysts. The recently discovered microbial electrosynthesis (MES) of high-value chemicals has greatly expanded the horizon for BES. Newer concepts in application as well as development of alternative materials for electrodes, separators, catalysts along with innovative designs have made BES very promising technology. This article discusses the recent developments that have been made in BESs so far, with the emphasis on their various applications beyond electricity generation and resulting performances as well as existing limitations.
Flow-through real time bacterial biosensor for toxic compounds in water
Eltzov, Evgeni ; Marks, Robert S. ; Voost, Stefan ; Wullings, Bart A. ; Heringa, Minne B. - \ 2009
Sensors and Actuators B: Chemical 142 (2009)1. - ISSN 0925-4005 - p. 11 - 18.
Bioreporter bacteria - Biosensors - Fiber optic - Toxicity
A flow-through fiber-optic-based bacterial monitoring system for online monitoring of toxic pollutants in water has been developed. Two bacterial strains containing fusions of recA (DNA damage) and grpE (heat-shock) promoters to the lux operon (CDABE) were immobilized on a fiber optic and tested for their ability to detect pollutants in flowing tap water and surface water. Conditions for running the system for 24 h were optimized and first experiments with the system show (1-h) response times and response heights similar to the previous static systems. Responses were related to the doses and the sensitivity is good (comparable to static systems), but needs to be increased to be able to monitor whether also the low guideline values are exceeded by pollutants. 24-h measurements in tap water demonstrate the ability of the device to run for such a time period, but in river water loss of functionality of the bacteria was observed. This flow-through fiber-optic-based monitoring system has proven to be a useful next step in the development of a simple on-line real time sensor for relevant human toxicants in flowing water.