NEW MEDIUM FOR RAPID SCREENING AND ENUMERATION OF CLOSTRIDIUM-PERFRINGENS IN FOODS
NEW MEDIUM FOR RAPID SCREENING AND ENUMERATION OF CLOSTRIDIUM-PERFRINGENS IN FOODS
复制标题
DOI：
10.1128/aem.36.4.567-571.1978
复制
发表时间：
1978-01-01
影响因子：
4.4
通讯作者：
DEIBEL, RH
中科院分区：
文献类型：
--
作者：
ERICKSON, JE;DEIBEL, RH
研究了一种用于估算少量产气荚膜梭菌的快速灵敏方法，并与食品工业目前使用的方法进行了比较。在对自然污染和接种食品的回收研究中，将新型液体培养基RPM（快速产气荚膜梭菌培养基）与亚硫酸盐 - 多粘菌素 - 磺胺嘧啶琼脂以及胰蛋白胨 - 亚硫酸盐 - 环丝氨酸琼脂进行了比较。该培养基由石蕊牛奶和添加了葡萄糖、蛋白胨、明胶、酵母提取物、氯化钠和硫酸亚铁的液体硫乙醇酸盐培养基混合而成。选择性基于培养基中加入的抗生素系统（硫酸多粘菌素B和硫酸新霉素），并结合在46℃ - 48℃下培养24小时。如果观察到汹涌发酵，则将试管判定为阳性。所有显示汹涌发酵的试管都被确认为含有产气荚膜梭菌。在总共774个自然污染的食品样本中，使用RPM时有546个样本（71%）含有产气荚膜梭菌，但使用亚硫酸盐 - 多粘菌素 - 磺胺嘧啶琼脂时只有168个样本（22%）呈阳性。使用RPM从85个其他样本中的71%分离出了产气荚膜梭菌，而使用胰蛋白胨 - 亚硫酸盐 - 环丝氨酸琼脂时只有14%。使用最大可能数技术对14个单独样本进行的计数研究也表明RPM具有更高的灵敏度。
A rapid and sensitive procedure for estimating low numbers of C. perfringens was investigated and compared to methods used currently in the food industry. The new liquid medium, RPM (rapid perfringens, medium), was compared with sulfite-polymyxin-sulfadiazine agar and tryptose-sulfite-cycloserine agar in recovery studies with naturally contaminated and with inoculated foods. The medium consists of a mixture of litmus milk and fluid thioglycolate medium fortified with glucose, peptone, gelatin, yeast extract, NaCl and ferrous sulfate. Selectivity is based on an antibiotic system (polymyxin B sulfate and neomycin sulfate) incorporated into the medium, coupled with an incubation temperature of 46.degree.-48.degree. C for 24 h. Tubes were scored as positive if a stormy fermentation was observed. All tubes demonstrating stormy fermentation were confirmed as containing C. perfringens. Of a total of 774 naturally contaminated food samples, 546 samples (71%) contained C. perfringens with RPM, but only 168 (22%) of the samples were positive using sulfite-polymyxin-sulfadiazine agar. C. perfringens was isolated from 71% of 85 other samples using RPM as compared to 14% with tryptose-sulfite-cycloserine agar. Enumeration studies on 14 individual samples using the most probable number technique also demonstrated greater sensitivity with RPM.