Fig. 5
Schematic of species with the top four greatest relative abundance and the proposed pathway of substrates, VFA intermediate and VFA product. a In the control case some acetate (C2) and propionate (C3) may be used as an intermediate by Megasphaera sp. b In the experimental (applied current) case the Megasphaera sp. can metabolize electrolytically generated H2 to gain additional energy and through generating more reduced, longer chain VFA by lactate elongation