International Journal of Hydrogen Energy, Vol.44, No.20, 9856-9865, 2019
Biohydrogen production by vermihumus-associated microorganisms using agro industrial wastes as substrate
Typically dark fermentation is performed using activated sludge consortia and there are not studies on hydrogen production using vermihumus-associated microorganisms documented. Microorganisms from Eisenia foetida casting have proven an efficient anti recalcitrant activity. We have evaluated hydrogen production by Eisenia foetida lixiviated earthworm as inoculum using agro industrial wastes as substrate. Experiments were performed in 120 ml serological bottles under anaerobic conditions at 40 degrees C by triplicate. The results showed a hydrogen production of 1571.81, 1246.36 and 232.72 ml(H2)L(-1) from molasses, bagasse and vinasse, respectively. Butyric and acetic acids were the main metabolites produced reaching up to 6.0 and 1.26 gL(-1), respectively. Butanol and ethanol were also produced, but the maximum concentrations attained were 1.7 and 0.28 gL(-1), respectively. Interestingly, the bagasse did not require a pretreatment. The results demonstrated that vermihumus-associated microorganisms are capable of producing hydrogen from the recalcitrant raw materials such as the sugarcane bagasse. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.