克罗诺巴克特萨卡扎基菌株在婴儿配方奶粉中高温时的可变耐热性
Peter Myintzaw1, Fiona Ryan1, Caitriona Guinane1
1Munster Technological University, Rossa Ave, Bishopstown, Cork, T12 P928, Ireland.
International journal of food microbiology
|February 24, 2026
概括
在粉末婴儿配方 (PIF) 中的Cronobacter sakazakii可以在高温下生存. 菌株特定的遗传因素会影响这种耐热性,影响PIF的食品安全控制策略.
科学领域:
- 食品微生物学 食品微生物学
- 细菌遗传学 细菌遗传学
- 公共卫生 公共卫生
背景情况:
- 克罗诺巴克特萨卡扎基 (Cronobacter sakazakii) 对公众健康构成重大风险,特别是在婴儿配方奶粉 (PIF) 中.
- 高温加工是PIF安全的关键控制点,但细菌耐热性仍然是一个问题.
研究的目的:
- 为了研究不同Cronobacter sakazakii菌株在干燥PIF矩阵中暴露于高温 (90°C) 的耐热性.
- 确定与Cronobacter sakazakii.i.增强的耐热性相关的遗传决定因素.
主要方法:
- 六种不同的Cronobacter sakazakii菌株在PIF矩阵中被测试在90°C的生存率.
- 多部位序列类型 (MLST) 用于菌株特征.
- 基因组分析确定了与耐热性相关的基因和潜在的基因组岛屿.
主要成果:
- 所有测试的Cronobacter sakazakii菌株在PIF矩阵中都经历了高温暴露,但在耐热性方面具有显著的菌株特异性变化.
- 韦布尔尺度参数 (δ) 在菌株之间有很大的差异,表明热失活率的差异.
- 基因hspA,yadV_1,yadV_2和一个完整的热耐性基因组岛 (thrB-Q) 的存在与增强的热耐性相关.
结论:
- 在PIF矩阵中,Cronobacter sakazakii在耐热性方面表现出显著的菌株依赖的变异性.
- 特定的遗传因素,包括某些基因和基因组岛屿,有助于增强耐热性.
- 了解这些遗传决定因素对于制定有效的控制策略来确保PIF安全至关重要.
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