DiGiacinto J V, Frazier W C
Appl Microbiol. 1966 Jan;14(1):124-9. doi: 10.1128/am.14.1.124-129.1966.
Cultures of coliform and Proteus bacteria, mostly from foods, were tested for their effect on growth of Staphylococcus aureus in Trypticase Soy Broth. Inhibition of the staphylococcus by these competitors increased with increasing proportions of inhibiting (effector) bacteria in the inoculum and decreasing incubation temperatures (37 to 10 C). Time required for 2 x 10(4) staphylococci to increase to 5 x 10(6) cells per milliliter, the minimal number assumed to be necessary for food poisoning, varied with the species of effector, the original ratio of effector bacteria to staphylococci in the medium, and the incubation temperature. When the original ratio was 100:1, the staphylococci did not reach 5 x 10(6) cells per milliliter at 10, 15, 22, or 30 C (with one exception), when growing with cultures representing six species of coliform bacteria and two of Proteus. When the ratio was 1:1, all effectors either greatly delayed the staphylococcus or prevented it from reaching hazardous numbers at 15 C, six of the eight caused a delay of 2 to 3 hr at 22 C, and only Escherichia coli delayed the coccus at 30 C. All effectors were ineffective at 22 and 30 C when original numbers of effectors and staphylococci were in the ratio 1:100. Greatest overall inhibition was by E. coli, E. freundii, and Proteus vulgaris, and these species were more effective than the others at 22 and 30 C. Aerobacter cloacae and Paracolobactrum aerogenoides were more effective at 15 C. In general, results were similar with different strains of a species. Except for Aerobacter aerogenes, Klebsiella sp., and P. aerogenoides, which apparently did not compete for nutrients, inhibition of the staphylococcus was by a combination of antibiotic substances and competition for nutrients.
对主要来源于食品的大肠菌群和变形杆菌进行培养，检测它们在胰蛋白酶大豆肉汤中对金黄色葡萄球菌生长的影响。随着接种物中抑制性（效应）细菌比例的增加以及培养温度的降低（37至10摄氏度），这些竞争者对葡萄球菌的抑制作用增强。每毫升2×10⁴个葡萄球菌增加到5×10⁶个细胞所需的时间（这是假定食物中毒所需的最小数量）因效应菌的种类、培养基中效应菌与葡萄球菌的原始比例以及培养温度而异。当原始比例为100:1时，在10、15、22或30摄氏度下（有一个例外），与代表六种大肠菌群细菌和两种变形杆菌的培养物一起生长时，葡萄球菌每毫升未达到5×10⁶个细胞。当比例为1:1时，所有效应菌要么极大地延迟了葡萄球菌的生长，要么在15摄氏度时阻止其达到危险数量，八种效应菌中有六种在22摄氏度时导致延迟2至3小时，只有大肠杆菌在30摄氏度时延迟了球菌的生长。当效应菌和葡萄球菌的原始数量比例为1:100时，所有效应菌在22和30摄氏度下均无效。总体抑制作用最强的是大肠杆菌、弗氏柠檬酸杆菌和普通变形杆菌，这些菌种在22和30摄氏度下比其他菌种更有效。阴沟肠杆菌和气产副大肠杆菌在15摄氏度时更有效。一般来说，同一菌种的不同菌株结果相似。除了产气杆菌、克雷伯氏菌属和气产副大肠杆菌显然不竞争营养物质外，对葡萄球菌的抑制是抗生素物质和营养物质竞争共同作用的结果。
