Study on attenuation of Escherichia coli 0157 with a combination of essential oil of spices.

大肠杆菌0157具有高度的传染性，并能产生导致出血性结肠炎和溶血性尿毒症综合征的蠕形细胞毒素。由于使用抗生素治疗0157感染被报道会增加毒素基因的表达，因此建立有效的治疗方法是当务之急。本研究的目的是建立香料精油对E.Coli0157的减毒作用。当我们考察了不同香料对E.Coli0157产胞毒素的影响时，Alspice对产胞毒素有很强的抑制作用。有效成分经分离鉴定为丁香酚。丁香酚对病原菌产生维细胞毒素1和2有抑制作用。当我们考察了不同香料对E.Coli0157耐酸性的影响时，生姜表现出很强的降低病原菌耐酸性的能力。β-Pinene、柠檬烯、丁香酚和生姜提取物的组合可以有效地减少病原菌的数量，抑制魔芋毒素的产生，并降低其耐酸性。

Escherichia coli 0157 has a highly infectious ability and produces verocytotoxin that causes hemorrhagic colitis and hemolytic uremic syndrome. Since therapy for 0157 infections with antibiotics is reported to increase expression of the toxin genes, establishing an effective treatment is a priority. The purpose of this study is the establishment of attenuation of E. coli 0157 with a combination of essential oils of spices.When we examined the effects of various spices on production of verocytotoxin by E. coli 0157, allspice showed a high suppressive effect on the verocytotoxin production. The effective component was isolated and then identified to be eugenol. Eugenol showed a suppressive effect on production of verocytotoxin 1 and 2 by the pathogen. When we examined the effects of various spices on acid- tolerance of E. coli 0157, ginger showed a high ability to reduce the acid-tolerance of the pathogen. A combination of β-pinene, limonene, eugenol, and ginger extract was highly effective on decreasing the population of the pathogen, suppressing the verocytotoxin-productivity, and reducing the acid- tolerance.