Biohydrogen production from space crew's waste simulants using thermophilic consolidated bioprocessing

Human waste simulants were for the first time converted into biohydrogen by a newly developed anaerobic microbial consortium via thermophilic consolidated bioprocessing. Four different BioH₂-producing consortia (denoted as C1, C2, C3 and C4) were isolated, and developed using human waste simulants as substrate. The thermophilic consortium C3, which contained Thermoanaerobacterium, Caloribacterium, and Caldanaerobius species as the main constituents, showed the highest BioH₂ production (3.999 mmol/g) from human waste simulants under optimized conditions (pH 7.0 and 60 °C). The consortium C3 also produced significant amounts of BioH₂ (5.732 mmol/g and 2.186 mmol/g) using wastewater and activated sludge, respectively. The developed consortium in this study is a promising candidate for H₂ production in space applications as in situ resource utilization.