Smith M V, Pierson M D
Appl Environ Microbiol. 1979 May;37(5):978-84. doi: 10.1128/aem.37.5.978-984.1979.
Oxidation-reduction potential (Eh) levels were measured and standardized to pH (Eh7) for Trypticase soy broth containing various concentrations of reducing agents. Prereduced Trypticase soy broth with no added reducing agents exhibited a potential of -141 mV. Ascorbic acid at 0.2 to 0.005% and sodium thioglycolate at concentrations below 0.05% produced an Eh7 higher than the prereduced Trypticase soy broth containing no added reducing agents. The addition of cysteine hydrochloride,2-mercaptoethanol, and sodium formaldehyde sulfoxylate to prereduced Trypticase soy broth resulted in a reduction of Eh7 compared to the system without added reducing agents. The order of relative reducing intensity (from highest to lowest) for the reducing agents when comparing molar concentration was: sodium formaldehyde sulfoxylate,2-mercaptoethanol, cysteine hydrochloride, sodium thioglycolate, and ascorbic acid. Optimal growth of the test organism occurred at low Eh7 and low concentration of the reducing agents. A direct correlation existed between growth of the test organism and -Eh7 x -log concentration of the reducing agent.
对含有各种浓度还原剂的胰蛋白胨大豆肉汤,测量其氧化还原电位(Eh)水平并将其标准化为pH值(Eh7)。未添加还原剂的预还原胰蛋白胨大豆肉汤的电位为-141 mV。0.2%至0.005%的抗坏血酸以及浓度低于0.05%的巯基乙酸钠所产生的Eh7高于未添加还原剂的预还原胰蛋白胨大豆肉汤。向预还原的胰蛋白胨大豆肉汤中添加盐酸半胱氨酸、2-巯基乙醇和甲醛次硫酸氢钠,与未添加还原剂的体系相比,会导致Eh7降低。比较摩尔浓度时,还原剂相对还原强度的顺序(从最高到最低)为:甲醛次硫酸氢钠、2-巯基乙醇、盐酸半胱氨酸、巯基乙酸钠和抗坏血酸。受试微生物在低Eh7和低浓度还原剂条件下实现最佳生长。受试微生物的生长与-Eh7×还原剂浓度的负对数之间存在直接相关性。