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[Acetate production by acidification-homoacetogenesis two-phase coupling process: effect of initial pH]
Yan-Qiu Nie1, He Liu, Guo-Cheng Du
1Laboratory of Environmental Biotechnology, School of Biotechnology, Southern Yangtze University, Wuxi 214122, China.
Sheng Wu Gong Cheng Xue Bao = Chinese Journal of Biotechnology
|September 8, 2007
Summary
Optimal initial pH for acetate production in a two-phase fermentation system is 10. This study investigated how initial pH affects volatile fatty acids and ethanol production, finding acetate dominance at pH 8-11.
Area of Science:
- Biotechnology and Bioengineering
- Environmental Microbiology
- Metabolic Engineering
Context:
- Investigating microbial conversion of glucose to valuable products.
- Utilizing a two-phase coupling system for enhanced fermentation efficiency.
- Employing heat-treated and activated anaerobic sludge as inoculum.
Purpose:
- To determine the optimal initial pH for acetate production.
- To analyze the impact of initial pH on volatile fatty acids and ethanol yields.
- To understand the metabolic shifts during acidification and homoacetogenesis phases.
Summary:
- Acetate production was optimized at an initial pH of 10 in a glucose-fed, two-phase anaerobic fermentation system.
- Initial pH significantly influenced volatile fatty acids and ethanol production, with ethanol-type fermentation at pH 5 and butyrate-type at pH 6-7.
- Acetate became the dominant product at initial pH values ranging from 8 to 11, with a subsequent decline in ethanol due to its conversion to acetate.
Impact:
- Provides crucial insights for optimizing industrial acetate production processes.
- Highlights the importance of pH control in microbial fermentation for targeted product synthesis.
- Contributes to the understanding of microbial metabolism in complex anaerobic environments.
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