Dey Debasish Kumar, Kang Sun Chul
Department of Biotechnology, Daegu University, Jillyang, Naeri-ri, Gyeongsan, Gyeongbuk, 38453, Republic of Korea.
Department of Biotechnology, College of Engineering, Daegu University, Jillyang, Naeri-ri, Gyeongsan, Gyeongbuk, 38453, Republic of Korea.
Microbiol Res. 2020 Aug;237:126489. doi: 10.1016/j.micres.2020.126489. Epub 2020 May 11.
Increasing multidrug-resistant pathogenic bacterial contamination in the environment has become the leading cause of food poisoning, resulting in life-threatening conditions due to late detection and limited therapeutic options. Escherichia coli O157:H7 is one such pathogen which is severely affecting the environmental livestock and ultimately leads to human infection. In this context, probiotics could be a useful strategy to minimize the growth of pathogens, as they produce several antimicrobial compounds and shows an exclusive competitive behavior against the pathogens. Therefore, supplementation of probiotics is wieldy accepted in the field of agriculture for the maintenance of animal's health. Previously, we reported that W. confusa DD_A7 possesses anti-bacterial and immune-stimulatory activity in-vitro. Therefore, in the present study, we investigated the impact of oral-administration of DD_A7 powder against E. coli O157:H7. The 6 days post-fertilized zebrafish larvae were used to evaluate the pathogenicity of the microbe. 1 × 10 CFU/ml of E. coli O157:H7 effectively induced the inflammatory response in zebrafish larvae. Where 1 × 10 CFU/ml DD_A7 pre-treatment prolonged the survivability of zebrafish larvae and improved the immune response of zebrafish larvae against pathogenic infection. The antibacterial property of DD_A7 against the pathogen correlated with the significant reduction of oxidative stress and host inflammatory response, by inhibiting NF-κB and its downstream signaling pathway. The findings demonstrated the prophylactic activity of DD_A7 suggesting that its supplementation improved the host defense mechanism by reducing oxidative stress. The growth of pathogen was effectively suppressed in the DD_A7 pre-treated larvae and maintained a healthy gastrointestinal environment in the zebrafish model.
环境中多重耐药病原菌污染的增加已成为食物中毒的主要原因，由于检测延迟和治疗选择有限，导致危及生命的情况。大肠杆菌O157:H7就是这样一种病原体，它严重影响环境中的牲畜，并最终导致人类感染。在这种情况下，益生菌可能是一种有用的策略，可将病原体的生长降至最低，因为它们会产生多种抗菌化合物，并对病原体表现出排他性的竞争行为。因此，在农业领域，补充益生菌已被广泛接受用于维持动物健康。此前，我们报道了困惑魏斯氏菌DD_A7在体外具有抗菌和免疫刺激活性。因此，在本研究中，我们研究了口服DD_A7粉末对大肠杆菌O157:H7的影响。受精后6天的斑马鱼幼虫用于评估该微生物的致病性。1×10 CFU/ml的大肠杆菌O157:H7可有效诱导斑马鱼幼虫的炎症反应。而1×10 CFU/ml DD_A7预处理可延长斑马鱼幼虫的存活时间，并改善斑马鱼幼虫对病原体感染的免疫反应。DD_A7对病原体的抗菌特性与通过抑制NF-κB及其下游信号通路显著降低氧化应激和宿主炎症反应相关。研究结果证明了DD_A7的预防活性，表明其补充通过降低氧化应激改善了宿主防御机制。在DD_A7预处理的幼虫中，病原体的生长得到有效抑制，并在斑马鱼模型中维持了健康的胃肠道环境。
