Hartung J
Zentralbl Bakteriol Mikrobiol Hyg B Umwelthyg Krankenhaushyg Arbeitshyg Prav Med. 1986 Dec;183(1):47-57.
The influence of three antibiotics (Penicillin G, Oxtetracycline, Polymyxin B), which show different modes of action against gram-negative bacteria, is tested on the growth of liquid E. coli cultures in a flow microcalorimeter. The antibiotics were added during the logarithmic growth phase of the culture when a heat flux of 40 mu W/ml was approached. A supply vessel and a reaction vessel were used for establishing of the baseline and for performing the test, respectively. When testing Oxytetracycline and Polymyxin B the germ content in the nutrient broth was determined, additionally. Some measurements of the optical density of the nutrient broth were carried out parallel to the microcalorimetric investigation on the effect of Polymyxin B. As was to be expected, Penicillin G shows an influence on E. coli at concentrations of about 50 microgram/ml medium, only. An influence of Oxytetracycline on the heat production can be observed at concentrations between 0.3 and 0.6 microgram/ml. Polymyxin B acts on the power-time-curve at 0.025 microgram/ml. The minimum doses of Oxytetracycline and Polymyxin B found by the microcalorimetric technique are distinctly lower than those found by bacterial count and by measuring the optical density. Microcalorimetric results are achieved within 2 hours after adding the test substance to the bacterial culture. Flow microcalorimetry seems to be a promising tool for testing antibacterial drugs.
在流动式微量量热计中，测试了三种对革兰氏阴性菌作用方式不同的抗生素（青霉素G、土霉素、多粘菌素B）对大肠杆菌液体培养物生长的影响。在培养物对数生长期，当热流接近40 μW/ml时添加抗生素。分别使用供应容器和反应容器来建立基线和进行测试。在测试土霉素和多粘菌素B时，还测定了营养肉汤中的细菌含量。在对多粘菌素B的作用进行微量量热研究的同时，还平行进行了一些营养肉汤光密度的测量。正如预期的那样，青霉素G仅在培养基浓度约为50微克/毫升时对大肠杆菌有影响。在浓度为0.3至0.6微克/毫升之间可观察到土霉素对产热的影响。多粘菌素B在0.025微克/毫升时对功率-时间曲线有作用。通过微量量热技术发现的土霉素和多粘菌素B的最小剂量明显低于通过细菌计数和测量光密度发现的剂量。在将测试物质添加到细菌培养物后2小时内即可获得微量量热结果。流动式微量量热法似乎是一种很有前途的抗菌药物测试工具。
