Non-thermal methods to disinfect enterohemorhagic Escherichia coli contamination in salad vegetables

非热法消毒沙拉蔬菜中肠出血性大肠杆菌污染

• 批准号: 13680154
• 负责人: NISHIKAWA Yoshikazu
• 金额: $ 1.02万
• 依托单位: Osaka City University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680154/
• 关键词: EHEC; O157; decontamination; non-thermal; Food; vegetables; pulsed electric fields; heated shell powder; オゾン

A strain of enterohemorrhagic Escherichia coil O157 was transformed by the plasmid which contained the green fluorescence protein gene. Artificially contaminated lettuce was produced by soaking the leaves in the suspension of the bacterium. Neglecting preexisting bacterial flora the number of O157 were accurately counted for their fluorescence under irradiation of UV. Throughout this research various kinds of chemical reagents and treatment-conditions were examined for disinfecting effects. Heated shell-powder solution showed strong bactericidal activity on lettuce rather than hypochlorite. A part of the inoculum seemed to have invaded to lettuce organization inside where the drug is difficult to reach and perfectly kills it. The O157 organisms were killed in 8-24 hour, when the lettuce was preserved at the low temperature after soaking in the shell-powder solution. Biopreservation is becoming attractive method for food safety. Although bacteria showing inhibitory effects against O157 were isolated from the human fecal specimens, it was not found among normal bacterial flora of foods throughout the experiments. It was suggested through some preliminary experiments that pulsed power electric discharge could possibly reduce the level of O157 contamination on lettuce.

将含有绿色荧光蛋白基因的质粒转化肠出血性大肠杆菌O 157。通过将叶子浸泡在细菌的悬浮液中，生产出了被细菌污染的莴苣。忽略预先存在的细菌植物群，在紫外光照射下准确计数O 157的数量。在整个研究过程中，对各种化学试剂和处理条件的消毒效果进行了检查。加热的贝壳粉溶液对生菜的杀菌活性强于次氯酸盐。一部分接种物似乎已侵入到药物难以到达的生菜组织内部，完全杀灭了O 157菌，将生菜浸泡在贝壳粉溶液中低温保存8-24 h，即可杀灭O 157菌。生物保藏是一种很有吸引力的食品安全方法。虽然从人粪便标本中分离出对O 157有抑制作用的细菌，但在整个实验过程中，在食物的正常细菌植物群中没有发现这种细菌。初步试验表明，脉冲功率放电有可能降低生菜O 157污染水平。

项目成果

西川禎一: "野菜の非加熱殺菌法について"防菌防黴. 31. 427-439 (2003)

Teiichi Nishikawa：“关于蔬菜的非加热灭菌方法”抗菌和抗真菌。 31. 427-439 (2003)

Nishikawa, Y., Hase, A., Ogasawara, J., Cheasty, T., Willshaw, G.A., Smith, H.R., Tasumi, Y., Yasukawa, A.: "Phage typing and DNA-based comparison of strains of enterohemorrhagic Escherichia coli O157 from apparently sporadic infections in Osaka City, Jap

Nishikawa, Y.、Hase, A.、Ogasawara, J.、Cheasty, T.、Willshaw, G.A.、Smith, H.R.、Tasumi, Y.、Yasukawa, A.：“噬菌体分型和基于 DNA 的肠出血菌株比较

Wani, S.A., Bhat, M.A., Samanta, I., Nishikawa, Y., Buchh, A.S.: "Isolation and characterization of Shiga toxin-producing Eschrichia coli (STEC) and enteropathogenic Escherichia coli (EPEC) from calves and lambs with diarrhoea in India"Lett.Appl.Microbiol

Wani, S.A.、Bhat, M.A.、Samanta, I.、Nishikawa, Y.、Buchh, A.S.：“来自腹泻犊牛和羔羊的产志贺毒素大肠杆菌 (STEC) 和肠致病性大肠杆菌 (EPEC) 的分离和表征

Nishikawa, Y.: "Classification of food-poisoning on the basis of kinds of foodstuff carrying pathogens"Iyaku Journal. 39. 1473-478 (2003)

Nishikawa, Y.：“根据携带病原体的食品种类对食物中毒进行分类”Iyaku Journal。

Zhou, Z., Nishikawa, Y., Zhu, P., Hong, S., Hase, A., Cheasty, T., Smith, H.R., Zheng, M., Haruki, K.: "(2002) Isolation and characterization of Shiga toxin-producing Escherichia coli O157 : H7 from beef, pork and cattle fecal samples in Changchun, China"

Zhou, Z.、Nishikawa, Y.、Zhu, P.、Hong, S.、Hase, A.、Cheasty, T.、Smith, H.R.、Zheng, M.、Haruki, K.：“(2002) 隔离与