Figure 1.

Methane production during the enrichment. Methane production (± SE) in enrichment phase 1 (A), 2 (B), 3 (C), 4 (D), 5 (E) and 6 (F) where closed circles = Chlorella vulgaris and U-C, closed squares = C. vulgaris and B-C, closed triangles = Dunaliella tertiolecta and U-D, and crosses = D. tertiolecta and B-D. H₂-fermenting cultures (with 20 mM BESA): C. vulgaris biomass as substrate = B-C; D. tertiolecta biomass as substrate = B-D; CH₄-producing cultures: C. vulgaris biomass as substrate = U-C; D. tertiolecta biomass as substrate = U-D. Crosses do not show, because they overlap with closed squares.