Increased Growth of a Hydrogenotrophic Methanogen in Co-Culture with a Cellulolytic Bacterium under Cathodic Electrochemical Regulation

Bioelectrochemical (−0.8 V, −0.3 V, and +0.6 V vs. Ag/AgCl) and non-bioelectrochemical co-cultures of a hydrogenotrophic methanogen and a cellulolytic bacterium were conducted. Unlike non-bioelectrochemical co-cultures, a cathodic reaction (−0.8 V) increased the growth of the hydrogenotrophic methanogen and the cellulolytic bacterium, by 6.0- and 2.2-fold respectively, and increased cellulose degradation. In contrast, anodic reactions (−0.3 V, +0.6 V) influenced them negatively.