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[Effect of nitrogen on avermectins biosynthesis and its fermentation optimization based on carbon-dioxide evolution
Yao Xu1, Tao Wu1, Meijin Guo1
1State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
This study optimized avermectin production by controlling nitrogen levels and yeast powder feeding in Streptomyces avermitilis fermentation. Results show enhanced B1a synthesis and a 26.9% increase in avermectin yield.
Area of Science:
- Microbiology
- Biotechnology
- Fermentation Technology
Background:
- China dominates global avermectin production but faces yield challenges compared to similar antibiotics.
- Improving avermectin yield is crucial for industrial applications and meeting global demand.
Purpose of the Study:
- To investigate the impact of nitrogen on Streptomyces avermitilis growth and avermectin B1a synthesis.
- To enhance avermectin production yield through optimized fermentation strategies.
Main Methods:
- Studied the effects of nitrogen on cell activity, packed-cell volume (PMV), and B1a synthesis during Streptomyces avermitilis fermentation.
- Implemented a feeding strategy using yeast powder, guided by carbon-dioxide evolution rate, in a 100-L bioreactor.
Main Results:
- Nitrogen significantly influenced cell activity, PMV, and B1a synthesis in the mid-to-late fermentation stages.
- The optimized feeding strategy led to a substantial improvement in B1a synthesis.
- Avermectin production increased by 26.9%, reaching 8,697 mg/L.
Conclusions:
- Optimizing nitrogen levels and employing a controlled yeast powder feeding strategy effectively enhances avermectin yield.
- This study provides a viable approach for improving industrial avermectin production efficiency.
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