高产3-羟基丁酮解淀粉芽孢杆菌的选育及发酵优化

Mutation and fermentation optimization of Bacillus amyloliquefaciens for acetoin production

摘要:

3-羟基丁酮 (Acetoin) 作为一种重要的食用香料和平台化合物被广泛应用于医药、食品等领域。为改善解淀粉芽孢杆菌Bacillus amyloliquefaciens的3-羟基丁酮生产能力，采用常压室温等离子体 (ARTP) 和60Co γ射线进行复合诱变，以3-羟基丁酮产量为分析指标，筛选获得最优突变株B. amyloliquefaciens H-5，3-羟基丁酮产量为68.2 g/L。为进一步实现3-羟基丁酮的高效生产，对此突变株进行5 L发酵罐水平的培养条件优化，并于30 L发酵罐上进行放大培养，最终3-羟基丁酮产量达85.2 g/L，较出发菌株B. amyloliquefaciens FMME088提高了26.8%。上述研究结果表明，ARTP和60Co γ射线复合诱变能够有效获得高产菌株，该突变株具有较高的工业化微生物发酵生产3-羟基丁酮的潜能。

关键词:解淀粉芽孢杆菌，3-羟基丁酮，常压室温等离子体，60Co γ射线，发酵条件优化

Abstract:

As a platform chemical, acetoin has a great potential of application in medicine and food industries. In order to improve the efficiency of acetoin production, Bacillus amyloliquefaciens was treated by atmospheric and room temperature plasma and gamma rays. Two-round screening was adopted for obtaining positive mutants, and the best mutant B. amyloliquefaciens H-5 produced acetoin up to 68.2 g/L in shake flask. Then, culture conditions were optimized in 5-L fermentor to enhance acetoin production. Finally, 85.2 g/L acetoin was produced by B. amyloliquefaciens H-5, which was increased by 26.8% compared with that of the original strain B. amyloliquefaciens FMME088. These results indicated that the high-producing strain can be obtained efficiently by compound mutagenesis, which has a promising prospect for commercial scale process.

Key words:Bacillus amyloliquefaciens, acetoin, atmospheric and room temperature plasma, 60Co gamma rays, fermentation optimization