营养因素特别促进乙醇发酵,但不能促进酵母菌的生长
Satoshi Ebe1, Yukie Misumi1, Yuki Terauchi2
1Division of Applied Chemistry, Graduate School of Sciences and Technology for Innovation, Yamaguchi University, 2-16-1 Tokiwadai, Ube 755-8611, Japan.
Journal of bioscience and bioengineering
|July 2, 2025
概括
确定了用于酵母乙醇发酵的特定营养素. 酸和pH控制通过增加二氧化碳排放来增强发酵,即使没有细胞生长.
科学领域:
- 生物化学 生物化学
- 微生物学 微生物学
- 工业生物技术 工业生物技术
背景情况:
- 酵母乙醇发酵对工业至关重要,但通常与细胞生长有关,掩盖了特定的发酵营养需求.
- 营养素,pH值和温度等环境因素显著影响酵母发酵和生长.
研究的目的:
- 为了阐明酵母乙醇发酵的特定营养需求.
- 为了区分发酵所必需的营养与支持细胞增殖的营养.
主要方法:
- 使用半合成介质,控制注射剂大小 (OD600 = 2,16 或 32),并监测二氧化碳排放.
- 系统地添加营养素 (酸,MgSO4,KH2PO4,myo-inositol) 和调整葡萄糖度和细胞数量以实现无生长发酵.
- 在没有增长的条件下,消除了中间成分,以确定基本因素.
主要成果:
- 在基底介质中添加酸 (Asp) 和MgSO4显著增加了二氧化碳排放.
- 进一步添加KH2PO4和myo-inositol可以提高发酵速度.
- 在高葡萄糖 (28.6%) 和注射条件下 (OD600 = 16 或 32),发酵与抑制细胞生长发生,Asp是增加CO2排放的关键.
- 在没有生长条件下提高发酵的关键被确定为酸和pH维护.
结论:
- 酸是一种关键的营养素,可以增强酵母乙醇发酵,独立于细胞生长.
- 优化pH值和补充酸可以提高工业环境中的发酵效率,特别是在旨在最大限度地减少细胞增殖的条件下.
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