Zajančkauskaitė Aurelija, Noreika Algirdas, Rutkienė Rasa, Meškys Rolandas, Kaliniene Laura
Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Center, Vilnius University, Sauletekio av. 7, LT-10257 Vilnius, Lithuania.
Foods. 2021 Jun 28;10(7):1500. doi: 10.3390/foods10071500.
Shiga toxin-producing (STEC) O26:H11 is an emerging foodborne pathogen of growing concern. Since current strategies to control microbial contamination in foodstuffs do not guarantee the elimination of O26:H11, novel approaches are needed. Bacteriophages present an alternative to traditional biocontrol methods used in the food industry. Here, a previously isolated bacteriophage vB_EcoM_VR26 (VR26), adapted to grow at common refrigeration temperatures (4 and 8 °C), has been evaluated for its potential as a biocontrol agent against O26:H11. After 2 h of treatment in broth, VR26 reduced O26:H11 numbers ( < 0.01) by > 2 log at 22 °C, and ~3 log at 4 °C. No bacterial regrowth was observed after 24 h of treatment at both temperatures. When VR26 was introduced to O26:H11-inoculated lettuce, ~2.0 log CFU/piece reduction was observed at 4, 8, and 22 °C. No survivors were detected after 4 and 6 h at 8 and 4 °C, respectively. Although at 22 °C, bacterial regrowth was observed after 6 h of treatment, O26:H11 counts on non-treated samples were >2 log CFU/piece higher than on phage-treated ones ( < 0.02). This, and the ability of VR26 to survive over a pH range of 3-11, indicates that VR26 could be used to control STEC O26:H11 in the food industry.
产志贺毒素大肠杆菌（STEC）O26:H11是一种日益引起关注的新出现的食源性病原体。由于目前控制食品中微生物污染的策略不能保证消除O26:H11，因此需要新的方法。噬菌体为食品工业中使用的传统生物防治方法提供了一种替代方案。在此，对一种先前分离的、适应于在常见冷藏温度（4和8°C）下生长的噬菌体vB_EcoM_VR26（VR26）作为针对O26:H11的生物防治剂的潜力进行了评估。在肉汤中处理2小时后，VR26在22°C下使O26:H11数量减少了>2个对数级（<0.01），在4°C下减少了约3个对数级。在这两个温度下处理24小时后均未观察到细菌再生长。当将VR26引入接种了O26:H11的生菜中时，在4、8和22°C下观察到每片生菜的CFU减少了约2.0个对数级。在8°C和4°C下分别处理4小时和6小时后未检测到存活菌。尽管在22°C下处理6小时后观察到细菌再生长，但未处理样品上的O:26:H11菌落数比噬菌体处理样品上的高>2个对数级CFU/片（<0.02）。这一点以及VR26在pH值3至11范围内存活的能力表明，VR26可用于食品工业中控制STEC O26:H11。
