National Key Laboratory of Agricultural Microbiology, Key Laboratory of Environment Correlative Dietology, College of Food Science and Technology, College of Biomedicine and Health, Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
China Institute of Veterinary Drug Control, Beijing 100086, China.
Food Res Int. 2023 Oct;172:113214. doi: 10.1016/j.foodres.2023.113214. Epub 2023 Jun 30.
Contamination of infant formula with Cronobacter sakazakii (C. sakazakii) can cause fatal infections in neonates. Phages have emerged as promising antibacterial agents for food safety, but their effectiveness may be limited by thermal processing. In this study, we isolated 27 C. sakazakii phages from environmental water samples and selected LPCS28 due to its broad lysis spectrum. The titer of LPCS28 will not be significantly affected by heating at a temperature of 60 °C for one hour. In both reconstituted powdered infant formula (RPIF) and liquid milk, the pre-added LPCS28, after the thermal processing at 63 °C for 30 min, significantly inhibited the post-contaminated C. sakazakii (10 CFU/mL) and eventually reduced the number of C. sakazakii to below the limit of detection (<10 CFU/mL) within 9 h at 37 °C and significantly delayed the increase of bacterial concentration in the samples at 23 °C. The phylogenetic analysis revealed that LPCS28 belonged to a new genus, we proposed as Nanhuvirus, under the family Straboviridae. These findings suggest that phage LPCS28 is a promising biological control agent for pathogenic C. sakazakii in the dairy industry.
阪崎克罗诺杆菌（Cronobacter sakazakii，C. sakazakii）污染婴儿配方奶粉可导致新生儿致命感染。噬菌体作为食品安全的有前途的抗菌剂已经出现，但它们的有效性可能受到热加工的限制。在这项研究中，我们从环境水样中分离出 27 株阪崎克罗诺杆菌噬菌体，并选择 LPCS28 因其广泛的裂解谱。LPCS28 的效价不会因在 60°C 加热 1 小时而受到显著影响。在复原的粉状婴儿配方（RPIF）和液态奶中，预先添加的 LPCS28 在 63°C 热加工 30 分钟后，可显著抑制污染后的 C. sakazakii（10 CFU/mL），并最终在 37°C 下 9 小时内将 C. sakazakii 的数量减少到检测限以下（<10 CFU/mL），并显著延迟了 23°C 下样品中细菌浓度的增加。系统发育分析表明，LPCS28 属于一个新属，我们建议将其命名为 Nanhuvirus，属于 Straboviridae 科。这些发现表明噬菌体 LPCS28 是乳制品工业中致病性 C. sakazakii 的有前途的生物控制剂。
