利用响应面法优化固氮类芽孢杆菌Paenibacillus sp.1-49的发酵培养基

Medium optimization for nitrogen fixer Paenibacillus sp. 1-49

摘要:

[目的]固氮类芽孢杆菌Paenibacillus sp.1-49是本实验室分离的具有潜在生物肥料价值的微生物菌剂。该菌在常见的培养基中不能高效生长（OD₆₀₀≤1）。本文拟优化发酵培养基成分以获得最大菌体生物量。[方法]运用响应面分析中的因素筛选实验设计和最陡爬坡实验以及中心复合设计法，对菌株的发酵培养基进行了响应面优化。[结果]利用响应面优化法最终确定了菌株最佳培养基：蔗糖36.22g/L，Tryptone 5.31 g/L，Yeast Extract 10.92 g/L，MgSO₄ 0.51 g/L，NaCl 3.5 g/L，Na₂MoO₄ 0.02 g/L，FeSO₄ 0.02 g/L。通过摇瓶发酵后菌体OD₆₀₀=10.280，达到预测值的94.6%。[结论]利用响应面法成功地对Paenibacillus sp. 1-49的发酵培养基进行了优化，为该菌株和其他类芽孢杆菌的大规模发酵提供了参考。

Abstract:

[Objective] Paenibacillus sp. 1-49 is a nitrogen-fixing bacterium that has the potential as a fertilizer. However, it grows poorly (OD₆₀₀≤1) in both mineral medium and rich medium. To achieve high-yield biomass, we optimized fermentation medium for Paenibacillus sp. 1-49.[Methods] Plackett-Burman Design and Central Composite Design in response surface methodology were used to optimize medium composition.[Results] The optimal fermentation medium contained:(per liter) 36.22 g Sucrose, 5.31 g Tryptone, 10.92 g Yeast Extract, 0.51 g MgSO₄, 3.5 g NaCl, 0.02 g Na₂MoO₄ and 0.02 g FeSO₄. The maximum OD₆₀₀ of 10.280±0.009 was obtained in shake flask fermentation, reached 94.6% of the predicted value.[Conclusion] We succeeded in using a response surface methodology to optimize the fermentation medium for Paenibacillus sp. 1-49. Our results will be useful for largescale fermentation of this strain and other Paenibacillus spp..