Department of Biotechnology, Cochin University of Science and Technology, Cochin, 682022, Kerala, India.
Arch Microbiol. 2021 Nov;203(9):5445-5452. doi: 10.1007/s00203-021-02522-0. Epub 2021 Aug 18.
This study used a set of different bacteriophages to control contaminations of Salmonella spp., a major food pathogen. A cocktail of four phages designated based on host range and in vitro lytic assay showed a lower bacteriophage insensitive mutant frequency and considerable stability at 4 °C and 28 °C up to 60 days. The work evaluated the effectiveness of cocktail of four phages in reducing Salmonella spp. in four different food matrices (liquid egg, eggshell, milk, lettuce). A maximum of 1.7 log reduction in Salmonella spp. was achieved upon treatment of liquid eggs with phage cocktail for 72 h at 4 °C. In milk, the application of phage cocktail reduced recoverable Salmonella spp. by 1.9 log and 1.8 log at 28ºC (6 h) and 4ºC (72 h), respectively. A significant 2.9 log reduction of Salmonella spp. was obtained in eggshell after a 6 h incubation and Salmonella spp. was beyond detection level after 24 h at 28ºC. The application of cocktail also reduced Salmonella spp. beyond the detectable level in lettuce after 8 h at 28 °C. Our results indicated considerable stability of phages in different food matrices. Taken together, our findings establish the potential effectiveness of the bacteriophage cocktail as a biocontrol agent for Salmonella spp. in different food matrices.
本研究使用了一组不同的噬菌体来控制沙门氏菌属的污染，沙门氏菌属是一种主要的食源性病原体。根据宿主范围和体外裂解试验，选定的四种噬菌体混合物在 4°C 和 28°C 下具有较低的噬菌体不敏感突变体频率和相当的稳定性，可长达 60 天。该工作评估了四种噬菌体混合物在减少四种不同食品基质（液态蛋、蛋壳、牛奶、生菜）中沙门氏菌属的有效性。在 4°C 下用噬菌体混合物处理液态蛋 72 小时，可使沙门氏菌属最大减少 1.7 个对数。在牛奶中，噬菌体混合物的应用可使可回收的沙门氏菌属减少 1.9 个对数和 1.8 个对数，分别在 28°C（6 小时）和 4°C（72 小时）下。在 28°C 孵育 6 小时后，蛋壳中沙门氏菌属的减少量达到了显著的 2.9 个对数，在 28°C 孵育 24 小时后，沙门氏菌属已无法检测到。在 28°C 下 8 小时后，混合物也可使生菜中的沙门氏菌属减少到无法检测到的水平。我们的结果表明噬菌体在不同的食品基质中具有相当的稳定性。综上所述，我们的研究结果确立了噬菌体混合物作为一种生物控制剂在不同食品基质中控制沙门氏菌属的潜在有效性。
