Survival of Listeria monocytogenes Scott a on metal surfaces:: Implications for cross-contamination
Survival of Listeria monocytogenes Scott a on metal surfaces:: Implications for cross-contamination
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DOI：
10.1016/j.ijfoodmicro.2006.04.037
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发表时间：
2006-09-01
影响因子：
5.4
通讯作者：
Keevil, C. William
中科院分区：
文献类型：
--
作者：
Wilks, Sandra A.;MichelS, Harold T.;Keevil, C. William
单核细胞增多性李斯特菌是一种常见于环境中的重要再生病原菌。许多疫情与食品污染有关，通常与表面或设备与预制食品的交叉污染有关。在本研究中，一些铜基金属合金已被用来评估的生存时间的L。与不锈钢相比，不同材料上的单核细胞增多症。将高浓度（10（7））的细菌置于从每种合金切割的金属试样上。在规定的孵育时间后，将试样置于含有磷酸盐缓冲盐水的试管中，并涡旋以除去细胞。然后将等分试样接种到胰蛋白胨血琼脂平板上，并计数菌落形成单位数。高浓度的细菌用于代表“最差情况”。结果表明，与不锈钢相比，铜基合金的存活率大大降低。在室温下孵育24 h后，可在不锈钢上检测到活细胞。在铜、黄铜、铝青铜和硅青铜上，孵育60分钟后未检测到活细菌，表明减少了5个对数（该程序的检测限为100个细菌）。孵育90分钟后，从铜镍合金和铜镍锌合金中未检测到细胞。活性染色剂5-氰基-2，3-二甲苯基四唑氯化物（CTC）证实了这些结果，24 h后在不锈钢上清楚地标记了活跃呼吸的细菌。结果表明，仔细选择表面材料可以降低工业，商业和家庭环境中交叉污染的潜在风险。(c)2006 Elsevier B. V.保留所有权利。
Listeria monocytogehes is an important re-emerging pathogen which is commonly found in the environment. Many outbreaks have been associated with the contamination of food produce, often linked to cross-contamination from surfaces or equipment to prepared foodstuffs. In the present study a number of copper-base metal alloys have been used to assess the survival times of L. monocytogenes on different materials, in comparison with stainless steel. High concentrations (10(7)) of bacteria were placed on metal coupons cut from each alloy. After defined incubation times, coupons were placed in tubes containing phosphate buffered saline and vortexed to remove the cells. Aliquots were then plated onto tryptone blood agar plates and the number of colony forming units counted. The high concentration of bacteria was used to represent a "worstcase" scenario. The results indicate that survival is greatly reduced on a copper-base alloy compared to stainless steel. Viable cells could be detected on stainless steel after 24 h incubation at room temperature. On copper, brass, aluminium bronze and silicon bronze, no viable bacteria could be detected after 60 min incubation, indicating a 5 log reduction (the detection limit of the procedure was 100 bacteria). No cells could be detected from copper nickel and copper nickel zinc alloys, after 90 min incubation. The viability stain, 5-cyano-2,3-ditolyl tetrazolium chloride (CTC), confirmed these results, with actively respiring bacteria being clearly labelled on stainless steel after 24 h. The results suggest that careful choice of surface material could reduce the potential risk of cross-contamination in industrial, commercial and domestic environments. (c) 2006 Elsevier B.V. All rights reserved.