Tolen Tamra N, Xie Yicheng, Hairgrove Thomas B, Gill Jason J, Taylor T Matthew
Department of Animal Science, Texas A&M University, College Station, TX 77843-2471, USA.
Foods. 2018 Jul 16;7(7):114. doi: 10.3390/foods7070114.
Microbiological safety of beef products can be protected by application of antimicrobial interventions throughout the beef chain. This study evaluated a commercial prototype antimicrobial intervention comprised of lytic bacteriophages formulated to reduce O157 and non-O157 Shiga-toxigenic (STEC) on beef cattle hide pieces, simulating commercial pre-harvest hide decontamination. STEC reduction in vitro by individual and cocktailed phages was determined by efficiency of plating (EOP). Following STEC inoculation onto hide pieces, the phage intervention was applied and hide pieces were analyzed to quantify reductions in STEC counts. Phage intervention treatment resulted in 0.4 to 0.7 log CFU/cm² ( < 0.01) O157, O121, and O103 reduction. Conversely, O111 and O45 did not show any significant reduction after application of bacteriophage intervention ( > 0.05). Multiplicity of infection (MOI) evaluation indicated O157 and O121 isolates required the fewest numbers of phages per host cell to produce host lysis. STEC-attacking phages may be applied to assist in preventing STEC transmission to beef products.
通过在牛肉产业链中应用抗菌干预措施，可以保护牛肉产品的微生物安全性。本研究评估了一种商业原型抗菌干预措施，该措施由裂解性噬菌体组成，旨在减少肉牛皮块上的O157和非O157产志贺毒素大肠杆菌（STEC），模拟商业收获前的皮张去污处理。通过平板计数效率（EOP）测定单个噬菌体和混合噬菌体在体外对STEC的减少情况。在将STEC接种到皮块上后，应用噬菌体干预措施，并对皮块进行分析以量化STEC数量的减少。噬菌体干预处理使O157、O121和O103减少了0.4至0.7 log CFU/cm²（<0.01）。相反，在应用噬菌体干预措施后，O111和O45没有显示出任何显著减少（>0.05）。感染复数（MOI）评估表明，O157和O121分离株在每个宿主细胞产生宿主裂解所需的噬菌体数量最少。攻击STEC的噬菌体可用于协助预防STEC传播到牛肉产品中。
