Bioaugmented hydrogen production from microcrystalline cellulose using co-culture—Clostridium acetobutylicum and Ethanoigenens harbinense

Dark fermentation of microcrystalline cellulose to produce biohydrogen using mono-culture or co-culture of isolated strains was studied. A strain ( X 9 ) with high hydrogen yield from microcrystalline cellulose was isolated and identified to be closely affiliated with Clostridium acetobutylicum, ATCC 824. At 37 ∘ C and pH 5.0, the mono-culture of X 9 yields hydrogen with a 5-h time lag and end liquid products primarily of acetate and butyrate. The co-culture of X 9 with another strain, Ethanoigenens harbinense B 49 , which can produce hydrogen efficiently from monosaccharides but directly from microcrystalline cellulose, produced more efficiently the biohydrogen via ethanol-type fermentation metabolism compared with mono-culture X 9 test. Bioaugmentation with X 9 + B 49 improved cellulose hydrolysis and subsequent hydrogen production rates as compared with that of mono-culture bioaugmentation with X 9 .