Figure 2.

Schematic bioreactor and anaerobic digester designs for industrial-scale use of anaerobic fungi. A lignocellulose (raft) layer forms due to biomass floating as anaerobic fungi ferment their substrate: (a) up-flow anaerobic digester where anaerobic fungi are grown ± methanogens to produce CH₄, H₂ and CO₂; (b) plug flow anaerobic digester; (c) continuous-flow bioreactor with intermittent substrate feeding; and (d) high dry matter (solid-state) bioreactor where anaerobic fungi ± methanogens grow directly on moist substrate. The bioreactor is flushed with CO₂ humidified with culture medium. Substrate is batch fed and residual lignocellulose can be used downstream in biotechnological processes.