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[Influence of substrate concentration on PHA production using fermented sugar cane as substrate]
Zhi-Qiang Chen1, Yi Deng, Long Huang
1State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090, China. czqhit@163.com
Huan Jing Ke Xue= Huanjing Kexue
|August 17, 2013
Summary
Optimizing polyhydroxyalkanoates (PHA) production involves controlling influent substrate concentration during culture selection. A concentration of 1,120 mg/L COD is identified as optimal for efficient PHA synthesis and operational stability.
Area of Science:
- Biotechnology
- Polymer Science
- Environmental Engineering
Context:
- Polyhydroxyalkanoates (PHA) are biodegradable polymers produced by microorganisms.
- The three-stage PHA synthesis process includes substrate hydrolysis, culture selection, and PHA synthesis.
- Culture selection is a critical stage impacting PHA production efficiency and often faces challenges like sludge bulking.
Purpose:
- To investigate the influence of influent substrate concentration on culture selection efficiency and operational stability in PHA production.
- To identify the optimal substrate concentration for enhancing bacterial enrichment and PHA yield.
- To explore the relationship between intracellular glycogen levels and PHA synthesis ability.
Summary:
- This study evaluated influent substrate concentrations of 560, 1,120, and 1,680 mg/L COD for PHA production.
- An influent substrate concentration of 1,120 mg/L COD was determined to be the most suitable for bacterial enrichment under short sludge retention time (SRT).
- After 94 days, optimal conditions yielded 50% PHA content, a 0.7145 COD/COD conversion rate, and a 0.1912 mg/(mg·h) specific PHA storage rate.
Impact:
- The findings provide crucial insights for optimizing PHA production processes by managing substrate concentration.
- Identifying the optimal substrate concentration can mitigate sludge bulking and improve overall process stability.
- The correlation between glycogen levels and PHA synthesis offers a potential method for predicting enrichment efficiency.
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