采用微量热安瓿法测定细菌生长时,发现细菌的代谢产热曲线在第一指数生长期内出现了停留法没有报导过的显著分阶段现象,且在不同的阶段生长速率常数有很大差异,对药物抗菌性能的评估造成极大干扰.为了寻找此现象的可能原因,以具有代表性的兼性细菌大肠杆菌为例,设计了微量热安瓿法实验,考察了不同环境气氛下大肠杆菌的生长代谢产热;并模拟了停留法条件下细菌的生长环境,通过安瓿法测定了大肠杆菌的生长代谢产热,重新解析了这些条件下细菌的生长速率常数.结果表明环境气氛是造成此现象的主要可能因素,并为在不同环境气氛下采用微量热安瓿法准确评估细菌的生长速率提供了一个可参考的标准.
A stage-like appearance occurred in the first exponential phase of several bacteria's thermogenic curves determined by a microcalorimetry ampoule method,and the growth rate constants of these stages were very different,which has not been found before in a stop-flow method and disturbs the precise antibacterial activity evaluation.In order to find the possible reasons,the growth of E.coli under different environmental atmosphere as well as the condition similar to the stop-flow method was determined and analyzed.The environmental atmosphere is mainly responsible for this variation.A criterion was recommended for the selection of growth rate constant under various atmosphere when determined by ampoule method.