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Published on: November 7, 2012
Effect of temperature on batch elastase production by Bacillus sp. EL31410
Guo-Qing He1, Ying Xu, Qi-He Chen
1Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310029, China. gqhe@zju.edu.cn
Journal of Zhejiang University. Science
|November 18, 2004
Summary
Cultivating Bacillus sp. EL31410 at 30°C optimizes elastase production. While higher temperatures enhance early cell growth, the peak elastase activity and formation rate were achieved at a constant 30°C.
Area of Science:
- Microbiology
- Biotechnology
- Enzyme Production
Background:
- Elastase is a crucial enzyme with diverse industrial applications.
- Optimizing fermentation conditions is key to maximizing enzyme yield.
- Temperature significantly influences microbial growth and enzyme synthesis.
Purpose of the Study:
- To investigate the effect of various cultivation temperatures on elastase production by Bacillus sp. EL31410.
- To determine the optimal temperature for maximizing elastase yield and specific growth rate.
- To compare constant temperature cultivation with dynamic temperature strategies.
Main Methods:
- Shake flask experiments evaluating temperatures from 28°C to 39°C.
- Batch fermentation in a 5-L bioreactor at 30°C and 37°C.
- Evaluation of two-stage temperature shift and oscillatory temperature cultivation modes.
Main Results:
- 37°C favored early cell growth, while 30°C yielded maximum elastase activity.
- The highest elastase formation rate (5.5 U/(h·g DCW)) occurred at 30°C after 24 hours.
- Constant 30°C cultivation resulted in the highest elastase production (652 U/ml), outperforming dynamic temperature strategies.
Conclusions:
- A constant cultivation temperature of 30°C is optimal for elastase production by Bacillus sp. EL31410.
- Dynamic temperature strategies (two-stage shift, oscillatory) improved biomass but not elastase yield compared to 30°C.
- Temperature optimization is critical for efficient microbial enzyme production.
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