Gvaladze Tamar, Lehnherr Hansjörg, Große-Kleimann Julia, Hertwig Stefan
Department Biological Safety, German Federal Institute for Risk Assessment, 10589 Berlin, Germany.
Phage Technology Center GmbH, 59199 Boenen, Germany.
Microorganisms. 2023 Sep 12;11(9):2298. doi: 10.3390/microorganisms11092298.
are important pathogenic bacteria and, following , they are the second most common cause of bacterial foodborne infections worldwide. To reduce the presence of bacteria along the food chain, the application of bacteriophages (phages) may be a promising tool. In this study, the lytic properties of six phages against five relevant serotypes ( Enteritidis, . Typhimurium, . Infantis, . Paratyphi B and . Indiana) were analyzed. Three phages were able to lyse all five serotypes. We determined the lytic potential of each phage on indicator strains in vitro at room temperature (RT) and at 37 °C using low multiplicities of infection (MOIs). Most phages reduced their host more efficiently at RT than at 37 °C, even at the lowest MOI of 0.001. Following this, the lytic activity of a cocktail comprising five phages (MOI = 0.1) was examined with each of the five serotypes and a mix of them at RT, 15, 12, 10, 8 and 6 °C. All cultures of single serotypes as well as the mixture of strains were significantly reduced at temperatures as low as 8 °C. For single serotypes, reductions of up to 5 log units and up to 2.3 log units were determined after 6 h (RT) and 40 h (8 °C), respectively. The mixture of strains was reduced by 1.7 log units at 8 °C. The data clearly suggest that these phages are suitable candidates for biocontrol of various serotypes under food manufacturing conditions.
是重要的病原菌，仅次于 ，是全球细菌性食源性感染的第二大常见原因。为了减少食物链中的细菌数量，应用噬菌体可能是一种有前途的工具。在本研究中，分析了六种噬菌体对五种相关血清型（肠炎沙门氏菌、鼠伤寒沙门氏菌、婴儿沙门氏菌、副伤寒乙沙门氏菌和印第安纳沙门氏菌）的裂解特性。三种噬菌体能够裂解所有五种血清型。我们在室温（RT）和37°C下，使用低感染复数（MOI），在体外测定了每种噬菌体对指示菌株的裂解潜力。即使在最低MOI为0.001时，大多数噬菌体在室温下比在37°C下更有效地减少其宿主菌数量。在此之后，在RT、15、12、10、8和6°C下，用五种血清型中的每一种以及它们的混合物检测了包含五种噬菌体（MOI = 0.1）的鸡尾酒的裂解活性。在低至8°C的温度下，所有单一血清型的培养物以及菌株混合物均显著减少。对于单一血清型，在6小时（RT）和40小时（8°C）后分别测定减少量高达5个对数单位和2.3个对数单位。在8°C下，菌株混合物减少了1.7个对数单位。数据清楚地表明，这些噬菌体是食品制造条件下对各种血清型进行生物防治的合适候选者。
