Tandem Integration of Aerobic Fungal Cellulase Production, Lignocellulose Substrate Saccharification and Anaerobic Ethanol Fermentation by a Modified Gas Lift Bioreactor
XUE (D), YAO (D), SUKUMARAN (R K), YOU (X), WEI (Z), GONG (C)
bioethanol; cellulase; gas lift bioreactor; aspergillus niger; saccharomyces cerevisiae
Cellulase production, lignocellulose saccharification and bioethanol fermentation were integrated to efficiently produce bioethanol. A modified gas lift bioreactor was developed for bioethanol production by the integrated process. Cellulase production was achieved using Aspergillus niger
mycelia immobilized within the reactor in wire meshes, and Saccharomyces cerevisiae
cells were immobilized in resin beads. During four repeated batches fermentation, cellulase activities were more than 6.28 U/mL and bioethanol production was over 45.9 g/L for 48 h. The factual bioethanol conversion efficiency was 86.8%. By the modification of the modified gas lift bioreactor, immobilization of Aspergillus niger
mycelia and Saccharomyces cerevisiae
cells, aerobic cellulase production, substrate saccharification and anaerobic bioethanol fermentation were successfully integrated in tandem. The integrated processes is of great significance in bioethanol production.