Bio-hydrogen Production from Cassava Pulp Hydrolysate using Co-culture of Clostridium butyricum and Enterobacter aerogenes

Biohydrogen production by co-fermentation of crude glycerol and apple pomace hydrolysate using co-culture of Enterobacter aerogenes and Clostridium butyricum

“…The hydrogen yield for C. butyricum (1.4 ± 0.1 mmol/mol) and E. aerogenes (0.8 ± 0.2 mmol/mol) almost reached theoretical maximum of hydrogen yield. These results justified the selection of best hydrogen producing microorganisms for the co-culture system in agreement with previous studies (Yokoi et al, 1998;Phowan et al, 2010).…”

“…The pH of the hydrolysate was adjusted to 10 using Ca(OH) 2 , the precipitate was removed by centrifugation at 381Âg for 15 min. The supernatant collected was re-acidified to pH 7.0 with further centrifugation to discard any sediment (Phowan et al, 2010). The final hydrolysate was stored at À20°C and used as a co-substrate along with CG for hydrogen production.…”

“…Till date, only few studies have reported H 2 production by co-culture using starch/glucose as substrate and process parameters, such as pH and media supplements have been optimized (Yokoi et al, 2002;Phowan et al, 2010). As seen from Table 1, studies dealing with co-substrate using crude glycerol are very scarce; they are focused mainly on the use of pure synthetic substrate, with no statistical optimization of the fermentation of crude glycerol using co-culture.…”

“…Research carried out using the Enterobacter and Clostridium with crude glycerol as substrate either produced ethanol (Ito et al, 2005;Jitrwung and Yargeau, 2011;Nwachukwu et al, 2012;Nwachukwu et al, 2013) or 1,3-propanediol (Zeng, 1996;Gonzalez-Pajuelo et al, 2004;Gonzalez-Pajuelo et al, 2005;Chatzifragkou et al, 2011;Szymanowska-Powałowska, 2014), which needs to be produced at higher concentration at the expense of media cost (Jitrwung and Yargeau, 2011). Additionally a co-culture of facultative (Enterobacter aerogenes) and strict anaerobe (Clostridium butyricum) can ensure high H 2 yield by using glucose as carbon source in the absence of expensive reducing agent (Yokoi et al, 1998;Phowan et al, 2010).…”

Biological hydrogen production using co-culture versus mono-culture system

“…[10] Combination of mesophilic and thermophilic anaerobic bacteria proved great potential for hydrogen production with an effective utilization of cellulase without addition of exogenous cellulase for cellulose hydrolysis in an interactive cooperation during co-culture system [11] and use of facultative bacteria as reducing agent reduced increased cumulative hydrogen production by 14.50% in comparison with mono-culture. [12] In order to reduce the expensive polypeptone usage, Yokoi et al [13] used corn steep liquor as a nitrogen source in the co-culture media for effective and economical hydrogen production. The co-culture system can increase hydrogen production rate in comparison with the mono-culture system [13] and also has demonstrated a hydrogen yield near to the theoretical maximum hydrogen yield.…”