Role of curli and plant cultivation conditions on Escherichia coli O157:H7 internalization into spinach grown on hydroponics and in soil.
Role of curli and plant cultivation conditions on Escherichia coli O157:H7 internalization into spinach grown on hydroponics and in soil.
复制标题
Curli 和植物栽培条件对大肠杆菌 O157:H7 内化到水培和土壤中菠菜中的作用。
DOI：
10.1016/j.ijfoodmicro.2013.12.004
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发表时间：
2014
影响因子：
5.4
通讯作者：
V. Sharma
中科院分区：
文献类型：
--
作者：
D. Macarisin;J. Patel;V. Sharma
新鲜农产品的污染可能是一个公共卫生问题，因为在收获期间或在加工设施中没有采取最终杀灭步骤来杀灭病原体。此外，一旦受到污染，病原体可能会内化到农产品中，并在采后加工步骤中受到消毒剂的保护。本研究的目的是确定大肠杆菌O157：H7可能内化到菠菜根中并随后转移到可食用部分。由于Curli参与生物膜的形成，我们研究了它们的存在是否影响E的内化。将大肠杆菌O157：H7加入菠菜中。此外，菠菜品种的影响也是如此。对大肠杆菌O157：H7的内化作用进行了评价。菠菜种植在受污染的土壤和水培中，以防止根的机械伤害和病原体从污染源无意中转移到未暴露的植物表面。结果表明，这是一种有效的治疗方法。ColiO157：H7可以通过根系内化到水培完整的菠菜植株中，并向茎和叶水平移动。在水培植物中，当根暴露于7万亿克CFU/毫升时，内化的发生率显著高于暴露于5万亿克CFU/毫升的植物。品种一的效应。在所分析的菠菜品种中，ColiO157：H7的内化作用不显著(P<0.05)，内化发生率在Space和Waitiki之间几乎相等，分别为49.06%和50.94%。水培菠菜根系损伤增加了根腐病的发病率。大肠杆菌O157：H7内化和转运到植物的可食用部分。土壤中生长的植物的实验污染导致了比水培植物更多的内化事件，这表明这一点。大肠杆菌O157：H7的内化依赖于根的损伤，当植物生长在土壤中时，这种损伤更有可能发生。卷曲表情再见。ColiO157：H7对菠菜的根系吸收没有显著影响。
Contamination of fresh produce could represent a public health concern because no terminal kill step is applied during harvest or at the processing facility to kill pathogens. In addition, once contaminated, pathogens may internalize into produce and be protected from disinfectants during the postharvest processing step. The objective of the current study was to determine the potential internalization ofEscherichia coliO157:H7 into spinach roots and subsequent transfer to the edible parts. Because curli are involved in biofilm formation, we investigated whether their presence influence the internalization ofE. coliO157:H7 into spinach. Further, the effect of the spinach cultivar onE. coliO157:H7 internalization was evaluated. Spinach plants were grown in contaminated soil as well as hydroponically to prevent mechanical wounding of the roots and inadvertent transfer of pathogens from the contamination source to the non-exposed plant surfaces. Results showed thatE. coliO157:H7 could internalize into hydroponically grown intact spinach plants through the root system and move to the stem and leaf level. The incidence of internalization was significantly higher in hydroponically grown plants when roots were exposed to 7 log CFU/mL compared to those exposed to 5 log CFU/mL. The effect of cultivar onE. coliO157:H7 internalization was not significant (P > 0.05) for the analyzed spinach varieties, internalization incidences showing almost equal distribution between Space and Waitiki, 49.06% and 50.94% respectively. Wounding of the root system in hydroponically grown spinach increased the incidence ofE. coliO157:H7 internalization and translocation to the edible portions of the plant. Experimental contamination of the plants grown in soil resulted in a greater number of internalization events then in those grown hydroponically, suggesting thatE. coliO157:H7 internalization is dependent on root damage, which is more likely to occur when plants are grown in soil. Curli expression byE. coliO157:H7 had no significant effect on its root uptake by spinach plants.