Hydrogen Production by the Thermophilic Bacterium Thermotoga neapolitana

Abstract

As the only fuel that is not chemically bound to carbon, hydrogen has gained interest as an energy carrier to face the current environmental issues of greenhouse gas emissions and to substitute the depleting non-renewable reserves. In the last years, there has been a significant increase in the number of publications about the bacterium Thermotoga neapolitana that is responsible for production yields of H2 that are among the highest achievements reported in the literature. Here we present an extensive overview of the most recent studies on this hyperthermophilic bacterium together with a critical discussion of the potential of fermentative production by this bacterium. The review article is organized into sections focused on biochemical, microbiological and technical issues, including the effect of substrate, reactor type, gas sparging, temperature, pH, hydraulic retention time and organic loading parameters on rate and yield of gas production.

CO2-Induced Transcriptional Reorganization: Molecular Basis of Capnophillic Lactic Fermentation in Thermotoga neapolitana

“…Thermophilic bacteria, such as Thermotogales, have been acquiring an emerging attention in biotechnology for hydrogen production by digestion of organic residues (Conners et al, 2006;Elleuche et al, 2014;Pradhan et al, 2015). Among thermophilic bacteria, T. neapolitana shows an interesting potential for the simultaneous production of hydrogen and LA by CLF d'Ippolito et al, 2014;Pradhan et al, 2017).…”

“…The taxonomic group shares a rod shape and complex outer envelope called toga that surrounds the bacterial cell and forms a periplasmatic space around the poles (Angel et al, 1993). T. neapolitana and other sister species are good candidates for the sustainable and efficient conversion of food and agriculture residues to hydrogen (H 2 ) by Dark Fermentation (Conners et al, 2006;Manish and Banerjee, 2008;Hallenbeck and Ghosh, 2009;Guo et al, 2010;d'Ippolito et al, 2010;Elleuche et al, 2014;Pradhan et al, 2015Pradhan et al, , 2016a.…”

Enhancement of fermentative hydrogen production by Thermotoga maritima through hyperthermophilic anaerobic co-digestion of fruit-vegetable and fish wastes

“…Recently, some studies reported that the use of an atmosphere enriched in carbon dioxide stimulated the synthesis of lactate by T. neapolitana, which has similar characteristics to T. maritima. This process was named capnophilic lactic fermentation (fermentative CO 2 -dependent) where lactate formation was the result of the association of exogenous CO 2 with acetyl-CoA [9,47,48]. Dipasquale et al [47] showed that the high production of lactate (up to 0.6 mol mol À1 glucose) Fig.…”

Adsorption Behaviour of Lactic Acid on Granular Activated Carbon and Anionic Resins: Thermodynamics, Isotherms and Kinetic Studies

“…Recently, a heterolactic fermentation process with a new metabolic pathway named capnophilic (CO 2 -led) lactic fermentation (CLF) was found to be present in the hyperthermophilic marine bacterium Thermotoga neapolitana [6]. Under CLF conditions, both hydrogen and lactic acid are synthesized simultaneously unlike in the classic dark fermentation processes [6][7][8][9]. T. neapolitana fermentation takes place on a wide range of carbohydrate-rich substrates at 80 • C (353.15 K) and pH 6.5.…”