牛奶中肠毒素A的产生。
Production of enterotoxin A in milk.
作者信息
Donnelly C B, Leslie J E, Black L A
出版信息
Appl Microbiol. 1968 Jun;16(6):917-24. doi: 10.1128/am.16.6.917-924.1968.
Enterotoxin A production in milk was studied by use of variables of milk quality, initial numbers of enterotoxigenic staphylococci, incubation temperature, and time. In both raw and pasteurized milks having a low total viable count, enterotoxin was detected in minimal incubation times of 6 to 9 hr at 35 C, 9 to 12 hr at 30 C, 18 hr at 25 C, and 36 hr at 20 C, after inoculation with 10(6)Staphylococcus aureus cells per ml. When similar milks were inoculated with 10(4)S. aureus cells per ml, enterotoxin was detected in 12 hr at 35 C, 18 hr at 30 C, 24 to 36 hr at 25 C, and 48 to 96 hr at 20 C. In high-count raw milk, enterotoxin was detected only in samples inoculated with 10(6)S. aureus cells per ml and incubated at 35 C. Generally, a concentration of 5 x 10(7)S. aureus cells per ml of milk was reached before enterotoxin A was detected.
通过使用牛奶质量变量、产肠毒素葡萄球菌的初始数量、培养温度和时间来研究牛奶中产肠毒素A的情况。在总活菌数较低的生牛奶和巴氏杀菌牛奶中，每毫升接种10⁶个金黄色葡萄球菌细胞后，在35℃下培养6至9小时、30℃下培养9至12小时、25℃下培养18小时、20℃下培养36小时的最短培养时间内可检测到肠毒素。当每毫升接种10⁴个金黄色葡萄球菌细胞于类似牛奶中时，在35℃下12小时、30℃下18小时、25℃下24至36小时、20℃下48至96小时可检测到肠毒素。在高菌数的生牛奶中，仅在每毫升接种10⁶个金黄色葡萄球菌细胞并在35℃下培养的样品中检测到肠毒素。一般来说，在检测到肠毒素A之前，牛奶中金黄色葡萄球菌的浓度达到每毫升5×10⁷个细胞。
Zotero 插件