Abstract
The present study aims to prepare a Saccharomyces cerevisiae cell factory, to combine three bioprocesses in a single stage, including cellulolytic enzyme production, cellulose hydrolysis to glucose, and fermentation with low cost of nutrients to ethanol, without any genetic modification. Cell factories are prepared, in which S. cerevisiae cells are covered with starch gel (SG), either containing Trichoderma reesei (SG-T. reesei), or cellulase produced from T. reesei (SG-cellulase). The work comprises the cellulose bioconversion using S. cerevisiae/SG-cellulase, and S. cerevisiae/SG-T. reesei to carry out alcoholic fermentation in one batch with low nutrient cost. In addition, the effect of different concentrations of yeast in the cell factory on fermentation rate was examined. SEM, FTIR spectra analysis and cellulose fermentation were used to prove the successful preparation of cell factory and its activity to ferment cellulose in one combined bioprocess. The cellulose sourced from delignified sawdust was characterized with XRD spectra and porosimetry analysis. Cell factory models of S. cerevisiae/SG-T. reesei and S. cerevisiae/SG-cellulase were able to ferment cellulose from wood, obtaining 32% and 62% ethanol production yield, respectively. S. cerevisiae/SG-T. reesei and S. cerevisiae/SG-cellulase resulted to 4.07 and 7.30 mL ethanol/L, respectively. The final glucose concentration was very low (0–0.07 g glucose/L). It is also concluded that the increase of S. cerevisiae concentration in CF helped an improvement in the bioconversion process.
Original language | English |
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Article number | 102733 |
Journal | Biocatalysis and Agricultural Biotechnology |
Volume | 50 |
Early online date | 18 May 2023 |
DOIs | |
Publication status | Published (in print/issue) - 31 Jul 2023 |
Bibliographical note
Funding Information:Authors acknowledge the support of this work by the project “ Research Infrastructure on Food Bioprocessing Development and Innovation Exploitation – Food Innovation RI ” ( MIS 5027222 ), which is implemented under the Action “ Reinforcement of the Research and Innovation Infrastructure ”, funded by the Operational Programme “ Competitiveness, Entrepreneurship and Innovation ” ( NSRF 2014–2020 ) and co-financed by Greece and the European Union (European Regional Development Fund).
Publisher Copyright:
© 2023 Elsevier Ltd
Keywords
- Cellulose
- Trichoderma
- Cell factory
- Yeast
- Cellulase