高压后的温度和时间 - 细菌子的高压处理中忽略的参数
Rosa Heydenreich1, Alessia I Delbrück1, Alexander Mathys1
1Sustainable Food Processing Laboratory, Institute of Food, Nutrition and Health, Department of Health Science and Technology, ETH Zurich, Zurich, Switzerland.
International journal of food microbiology
|June 18, 2023
概括
高压 (HP) 处理有效地使细菌子无活化,处理后的条件显著影响子发芽和膜完整性. 优化这些条件对于为食品工业开发温和子无活化方法至关重要.
科学领域:
- 食品微生物学 食品微生物学
- 食品加工技术 食品加工技术
- 细菌子生理学 细菌子生理学
背景情况:
- 高压 (HP) 处理为细菌子无活化提供了一种非热方法.
- 了解HP后的子生理状态对于优化无活化疗效至关重要.
- 流细胞计 (FCM) 可以根据发芽和膜完整性来区分子子子群.
研究的目的:
- 通过使用FCM进行非常高压 (vHP) 处理后,研究Bacillus subtilis子的生理状态.
- 确定HP后化条件 (温度,时间) 对子发芽和膜损伤的影响.
- 阐明皮质-酸性酶 (CLEs) 和小酸-溶性-蛋白-SASP-降解酶在HP胞子不活化中的作用.
主要方法:
- 细菌细菌子受到550MPa和60°C的非常高压 (vHP) 的影响.
- 在HP后的化是在不同的温度 (冰,37°C,60°C) 和时间进行的.
- 使用流细胞计 (FCM) 与SYTO16 (发芽) 和化 (PI) (膜损伤) 染色.
- 分析了CLE (CwlJ,SleB) 和SASP降解酶的删除菌株.
主要成果:
- 后HP化条件显著影响了FCM检测到的子子群.
- 在37°C的化后HP加速发芽 (SYTO16吸收) 和诱导的膜损伤 (PI吸收),取决于HP的停留时间.
- 皮质-酸酶 (CLEs) CwlJ和SleB对于SYTO16和PI吸收至关重要,对HP条件表现出不同的敏感性.
- SASP降解程度可能解释SYTO16阳性亚群的变化.
结论:
- 后HP化条件是关键的,被忽视的参数,显著影响子不活化.
- 在HP后的酶活性 (CLEs,SASP降解酶) 恢复对于子发芽和无活化至关重要.
- 优化的HP后条件可以提高HP基子无活化的有效性,用于工业应用,特别是在食品工业.
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