Improving Hydrogen Fermentation Performance by Co-Culturing Clostridium perfringens with Megasphaera elsdenii

抄録

To realize a hydrogen society, methods to produce hydrogen in an environmentally friendly manner like hydrogen fermentation using biomass waste are required. In this study, we developed a new approach for producing bio-hydrogen at a lower CO₂ emission using two types of bacteria. To improve hydrogen yield and NaOH consumption, which causes CO₂ emission according to a life cycle assessment of process, a co-culture system of Clostridium perfringens HN001, which produces lactate as a by-product of hydrogen, and Megasphaera elsdenii JCM1772, which produces hydrogen from lactate, was designed based on lactate metabolism. In a pure culture of M. elsdenii, lactate was preferentially consumed over glucose, and the production of hydrogen from lactate was confirmed. In a pure culture of C. perfringens, the production of lactate as a by-product of hydrogen was observed. In the co-culture system of C. perfringens and M. elsdenii, an increase of 131% in hydrogen yield and a reduction of 58% in NaOH consumption were achieved compared to those in the pure culture of C. perfringens due to the conversion of lactate to hydrogen by M. elsdenii. This result demonstrates that the co-culture system contributes improvement of hydrogen yield and reduction of CO₂ emission from fermentation process.