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Published on: October 24, 2016
Continuous butanol fermentation from xylose with high cell density by cell recycling system
Jin Zheng1, Yukihiro Tashiro, Tsuyoshi Yoshida
1Laboratory of Microbial Technology, Division of Applied Molecular Microbiology and Biomass Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan. zhengjin2811@gmail.com
Bioresource Technology
|December 25, 2012
Summary
Continuous butanol production using Clostridium saccharoperbutylacetonicum N1-4 was optimized with cell recycling. This method significantly boosted butanol productivity from xylose fermentation, achieving a 6-fold increase.
Area of Science:
- Biotechnology
- Microbial Fermentation
- Bioenergy
Background:
- Xylose fermentation for butanol production is challenging due to microbial limitations.
- Continuous fermentation systems require careful control to prevent cell washout.
Purpose of the Study:
- To establish and characterize a continuous butanol production system using high-density Clostridium saccharoperbutylacetonicum N1-4 with cell recycling.
- To investigate the impact of cell recycling and dilution rates on butanol fermentation from xylose.
Main Methods:
- Continuous culture of Clostridium saccharoperbutylacetonicum N1-4 with and without cell recycling.
- Monitoring and control of pH and dilution rates during fermentation.
- Analysis of cell concentration and butanol productivity.
Main Results:
- Cell recycling increased cell concentration to 17.4 g L(-1) and butanol productivity to 1.20 g L(-1) h(-1) at a dilution rate of 0.26 h(-1).
- Maximum butanol productivity of 3.32 g L(-1) h(-1) was achieved at a dilution rate of 0.78 h(-1) with cell recycling, a 6-fold increase compared to systems without recycling.
- pH control was critical for avoiding cell washout in continuous culture without recycling.
Conclusions:
- Cell recycling is a highly effective strategy for enhancing butanol production from xylose using Clostridium saccharoperbutylacetonicum N1-4 in continuous fermentation.
- Optimized dilution rates in conjunction with cell recycling can significantly improve butanol yield and productivity for industrial applications.
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