Mith Hasika, Clinquart Antoine, Zhiri Abdesselam, Daube Georges, Delcenserie Véronique
Department of Food Science and FARAH, Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster 20, B43bis, Sart Tilman, B-4000 Liège, Belgium Department of Food Technology and Chemical Engineering, Institute of Technology of Cambodia, Russian Conf. Blvd, Phnom Penh, Cambodia
Department of Food Science and FARAH, Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster 20, B43bis, Sart Tilman, B-4000 Liège, Belgium.
FEMS Microbiol Lett. 2015 Jan;362(1):1-7. doi: 10.1093/femsle/fnu021. Epub 2014 Dec 4.
The aim of the current study was to determine, via reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis, the effect of oregano essential oil (Origanum heracleoticum) and carvacrol, its major component, on the expression of virulence-associated genes in enterohaemorrhagic Escherichia coli (EHEC) O157:H7 ATCC strain 35150. Both oregano oil and carvacrol demonstrated their efficacy firstly, by inhibiting the transcription of the ler gene involved in upregulation of the LEE2, LEE3 and LEE4 promoters and of attaching and effacing lesions and secondly by decreasing both Shiga toxin and fliC genes expression. In addition, a decrease in luxS gene transcription involved in quorum sensing was observed. These results were dose dependent and showed a specific effect of O. heracleoticum and carvacrol in downregulating the expression of virulence genes in EHEC O157:H7. These findings suggest that oregano oil and carvacrol have the potential to mitigate the adverse health effects caused by virulence gene expression in EHEC O157:H7, through the use of these substances as natural antibacterial additives in foods or as an alternative to antibiotics.
本研究的目的是通过逆转录定量聚合酶链反应（RT-qPCR）分析，确定牛至精油（牛至）及其主要成分香芹酚对肠出血性大肠杆菌（EHEC）O157:H7 ATCC 35150菌株中与毒力相关基因表达的影响。牛至油和香芹酚均显示出其功效，首先，它们抑制了参与上调LEE2、LEE3和LEE4启动子以及黏附和脱落损伤的ler基因的转录；其次，它们降低了志贺毒素和fliC基因的表达。此外，还观察到群体感应相关的luxS基因转录减少。这些结果具有剂量依赖性，表明牛至和香芹酚对下调EHEC O157:H7中毒力基因的表达具有特定作用。这些发现表明，通过将这些物质用作食品中的天然抗菌添加剂或作为抗生素的替代品，牛至油和香芹酚有可能减轻EHEC O157:H7中毒力基因表达所引起的不良健康影响。
