Enhancing anti-E. coli O157:H7 activity of composite phage nanofiber film by D-phenylalanine for food packaging
Enhancing anti-E. coli O157:H7 activity of composite phage nanofiber film by D-phenylalanine for food packaging
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DOI：
10.1016/j.ijfoodmicro.2022.109762
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发表时间：
2022-06-01
影响因子：
5.4
通讯作者：
Lin, Lin
中科院分区：
文献类型：
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作者：
Cui, Haiying;Yang, Xiaojing;Lin, Lin
大肠杆菌O157:H7（E. coli O157）仍然是引起食物中毒的主要致病菌株之一。在这里，我们建立了一种策略，可以同时去除游离的大肠杆菌 O157 及其形成的生物膜。通过将生活污水中分离的大肠杆菌O157噬菌体与D-苯丙氨酸（D-Phe）通过静电纺丝技术共封装到海藻酸钠（SA）/聚环氧乙烷（PEO）纳米纤维中，成功合成了复合纳米纤维（fP-NF）薄膜。并添加脱水海藻糖作为噬菌体保护剂。当SA:PEO为3:9时，纺丝溶液具有最佳的电导率和粘度，所得fP-NF的平均直径为421.87 nm，fP-NF薄膜的机械强度和透明度最好。 fP-NF薄膜的热稳定性良好，纤维中的噬菌体活性得到很好的保存。放置一周后，fP-NF膜中剩余的噬菌体数量仍接近10(6) PFU/mL，并且噬菌体在室温（25℃）和冷藏温度（4℃）下的累积释放效率均在70%以上。抗菌实验表明，与对照组相比，D-Phe的添加略微增强了纳米纤维膜对游离大肠杆菌O157的抗菌活性，8 h内杀菌率为99.74%。另一方面，D-Phe显着增强了纳米纤维膜对大肠杆菌O157生物膜的抑制活性，72小时内抑制率超过99.99%。应用结果进一步证实，添加D-Phe可显着增强纳米纤维膜对牛肉和果蔬短期贮藏过程中大肠杆菌O157增殖和生物膜形成的抑制活性。为新型活性食品包装材料的开发提供了重要的策略和参考。
Escherichia coli O157:H7 (E. coli O157) is still one of the main pathogenic strains causing food poisoning. Here in, we established a strategy that can simultaneously remove free E. coli O157 and the biofilms it forms. Composite nanofiber (fP-NF) films were synthesized successfully by co-encapsulating E. coli O157 phages which isolated from domestic sewage and D-phenylalanine (D-Phe) into sodium alginate (SA)/polyethylene oxide (PEO) nanofibers by electrospinning. And dehydrated trehalose was added as a phage protectant. When SA:PEO is 3:9, the spinning solution has the optimum conductivity and viscosity, the average diameter of the obtained fP-NFs is 421.87 nm, and the mechanical strength and transparency of the fP-NF film are the best. The thermal stability of the fP-NF film was good, and the phage activity in the fiber was well preserved. The remaining population of phages in fP-NF membranes was still close to 10(6) PFU/mL after one week of placement, and the cumulative release efficiencies of phages at both room temperature (25 ?C) and refrigerated storage temperature (4 ?C) were above 70%. The antibacterial experiment showed that compared with the control group, the addition of D-Phe slightly enhanced the antibacterial activity of the nanofiber films against free E. coli O157, and the bactericidal rate within 8 h was 99.74%. On the other hand, D-Phe significantly enhanced the inhibitory activity of the nanofiber films against E. coli O157 biofilms, with the inhibition rate exceeding 99.99% within 72 h. The application results further confirmed that the addition of D-Phe could significantly enhance the inhibitory activity of nanofiber films on E. coli O157 proliferation and biofilm formation during short-term storage of beef and fruits and vegetables. It provides an important strategy and reference for the development of new active food packaging materials.