High-Efficient Production of Cellulosic Ethanol from Corn Fiber Based on the Suitable C5/C6 Co-Fermentation <i>Saccharomyces cerevisiae</i> Strain
Menglei Li,
Fadi Xu,
Yuping Zhao,
Dongming Sun,
Jiao Liu,
Xiaolong Yin,
Zailu Li,
Jianzhi Zhao,
Hongxing Li,
Xiaoming Bao
Affiliations
Menglei Li
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Fadi Xu
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Yuping Zhao
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Dongming Sun
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Jiao Liu
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Xiaolong Yin
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Zailu Li
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Jianzhi Zhao
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Hongxing Li
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
Xiaoming Bao
State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
As a potential alternative to fossil-based fuels, cellulosic ethanol has attracted much attention due to its great benefit to energy sustainability and environmental friendliness. However, at present, the industrial competitiveness of cellulosic ethanol production is still insufficient compared with fossil-based fuels because of the higher costs. Expanding the range of lignocellulosic biomass may be a promising measure to promote the economical production of cellulosic ethanol. Corn fiber, a byproduct from the corn deep-processing, is an attractive feedstock for cellulosic ethanol production because of its rich carbohydrate content (generally exceeding 65% of dry weight), almost no transportation cost, and low lignin content allow it to be easily handled. This study first optimized the hydrolysis conditions, including the pretreatment and enzymolysis process based on dilute sulfuric acid, to achieve a high sugar yield. Then, the corn fiber hydrolysates obtained under different hydrolysis conditions were suitably fermented by different C5/C6 co-fermentation Saccharomyces cerevisiae, indicating that the hydrolysate at high solid loading (20%) needs to detoxification to a certain extent but not low solid loading (10%) to achieve high ethanol yield. Finally, the fermentation of the 20% solid loading hydrolysates with resin detoxification was performed in a 50 L bioreactor, achieving the sugar (glucose and xylose) metabolic rate of 2.24 g L −1 h −1 and ethanol yield of 92% of the theoretical value, which are the highest reported levels to date. This study provided a potential process route for cellulosic ethanol production from corn fiber from the perspective of the suitability between the upstream hydrolysis process and the downstream fermentation strain.
