Impact of operating conditions on performance of a novel gas double-dynamic solid-state fermentation bioreactor (GDSFB).

A self-designed novel solid-state fermentation (SSF) bioreactor named "gas double-dynamic solid-state fermentation bioreactor (GDSFB)" showed great success in processes for the production of several valuable products. For the present study, a simple GDSFB (2 L in volume) was designed to investigate the impact of exhaust time on SSF performance. Both air pressure and vent aperture significantly influenced the exhaust time. The production of cellulase by Penicillium decumbens JUA10 was studied in this bioreactor. When the vent aperture was maintained at 0.2 cm, the highest FPA activity of 17.2 IU/g dry solid-state medium was obtained at an air pressure of 0.2 MPa (gauge pressure). When the air pressure was maintained at 0.2 MPa, a vent aperture of 0.3 cm gave the highest FPA activity of 18.0 IU/g dry solid-state medium. Further analysis revealed that the exhaust time was a crucial indicator of good performance in GDSFB.