Kim Jin-Hee, Oh Se-Wook
Department of Foods and Nutrition, Kookmin University, Seoul, 136-702 Korea.
Food Sci Biotechnol. 2020 May 3;29(8):1149-1157. doi: 10.1007/s10068-020-00758-y. eCollection 2020 Aug.
Foodborne bacteria are typically present at very low concentrations in food. This study describes a quick and simple method for concentrating O157:H7 present in lettuce and cabbage, without microbial enrichment culture. This method involved reducing the extraction buffer and DNA elution volumes. The extraction buffer volume was adjusted to 225, 100, 50, 25, and 12.5 mL to isolate O157:H7 from 25 g of lettuce or cabbage. DNA was concentrated and compared using real-time PCR. When using 12.5 mL of buffer, < 4 CFU/g of O157:H7 could be detected within 2 h without enrichment. This result is 100-fold sensitive than pretreatment with of the conventional method using 225 mL. It is suggested that this method could contribute to the prevention of food poisoning accidents in institutional catering settings, such as schools or military facilities, by the rapid and sensitive detection of pathogens without special equipment prior to food consumption stages.
食源性病原体在食物中的含量通常非常低。本研究描述了一种快速简便的方法，用于浓缩生菜和卷心菜中存在的O157:H7，无需进行微生物富集培养。该方法包括减少提取缓冲液和DNA洗脱体积。将提取缓冲液体积调整为225、100、50、25和12.5 mL，以从25 g生菜或卷心菜中分离O157:H7。使用实时PCR对DNA进行浓缩和比较。当使用12.5 mL缓冲液时，无需富集即可在2小时内检测到<4 CFU/g的O157:H7。该结果比使用225 mL的传统方法预处理灵敏100倍。建议该方法可通过在食品消费阶段之前无需特殊设备即可快速灵敏地检测病原体，有助于预防学校或军事设施等机构餐饮场所的食物中毒事故。
