对乳酸细菌对冷或喷雾干燥和储存的抗性差异的机制研究
Maite Gagneten1, Stéphanie Passot2, Stéphanie Cenard2
1Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, ITAPROQ (UBA- CONICET), Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina.
Applied microbiology and biotechnology
|June 5, 2024
概括
乳酸细菌 乳酸细菌 乳酸细菌 乳酸细菌 Delbrueckii亚种. 布尔加里克斯 (Bulgaricus) 和乳植物菌 (Lactiplantibacillus plantarum) 在干燥过程中表现出不同的抗应力. 牛乳杆菌delbrueckii亚种. 这种细菌. 布尔加里克斯对透性,机械和热应力敏感,而乳酸植物菌植物对热应力更敏感.
科学领域:
- 食品微生物学 食品微生物学
- 生物技术是生物技术.
- 食品保存 食品的保存方法
背景情况:
- 乳酸细菌 (LAB) 在食品发酵中至关重要.
- 在干燥过程中评估LAB存活率对于工业应用至关重要.
- 了解压力反应机制可以为保存策略提供信息.
研究的目的:
- 为了评估Lactobacillus delbrueckii亚种的耐药性. 布尔加里克斯和乳植物植物菌植物结和喷雾干燥.
- 调查这些LAB菌株活动丧失的潜在机制.
- 为了将细菌的应激反应与干燥矩阵的物理性质相关联.
主要方法:
- 培养能力和酸性活性测试以确定特定的酸性活性.
- 流细胞计用于膜完整性的评估.
- 差分扫描热量计 (DSC) 用于玻璃过渡温度 (Tg).
- 水活动测量. 水活动测量.
- 福利埃变换红外 (FTIR) 微光谱仪用于生物化学分析.
主要成果:
- 牛乳杆菌delbrueckii亚种. 这种细菌. bulgaricus CFL1对透性,机械和热应力表现出敏感性.
- 乳液植物菌植物 WCFS1对透和机械应力有更好的耐受性,但对热应力有更高的敏感性.
- FTIR分析表明膜和细胞壁的降解在Lb. 在热不活化后,Bulgaricus和核酸/蛋白质在两种菌株中的变化.
- 储存期间活动的丧失被确定为化学有限反应,受玻璃基质的物理性质的影响.
结论:
- 特定的FTIR频段可以作为LAB中透,机械和热应激的标记.
- Lb. 的差应力承受能力. 布尔加里克斯和Lpb. 植物的影响影响它们适合不同的干燥方法.
- 保持玻璃过渡温度至少比储存温度高40°C对于有效保存LAB功能至关重要.
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