RE(Hsal)2•(tch)•2H2O配合物与大肠杆菌作用的热动力学研究

用TAM air微量热仪测定了新合成的稀土水杨酸硫代脯氨酸配合物RE(Hsal)2•(tch)•2H2O (RE＝La, Sm; Hsal＝C7H5O3; tch＝C4H6NO2S)在37.00 ℃时对大肠杆菌作用的产热曲线; 根据产热曲线求算了在稀土水杨酸硫代脯氨酸配合物作用下, 大肠杆菌生长代谢的最大发热功率Pmax、速率常数k、传代时间tG、抑制率I和半抑制浓度cI,50等热动力学参数. 结果表明: 稀土水杨酸硫代脯氨酸配合物在低浓度下对大肠杆菌有刺激作用, 高浓度下为抑制作用, 即稀土配合物对微生物的生长具有双向生物效应, 也称为Hormesis效应. 配合物La(Hsal)2•(tch)•2H2O和Sm(Hsal)2•(tch)•2H2O的半抑制浓度cI,50分别为7.60和1.62 mg•L－1. 即配合物Sm(Hsal)2•(tch)•2H2O的抑制效果优于La(Hsal)2•(tch)•2H2O.

Thermokinetic Studies of Action of Complexes RE(Hsal)2•(tch)•2H2O on Growth Metabolism of Escherichia. Coli

The thermokinetic properties of the action of two kinds of complexes RE(Hsal)2•(tch)•2H2O (RE＝La, Sm, Hsal＝salicylate C7H5O3, tch＝thiaproline C4H6NO2S) on growth metabolism of Escherichia coli were studied by means of a TAM air isothermal calorimeter at 37.00 ℃. The maximum heat output power Pmax, growth rate constant k, generation time tG, inhibitive ratio I (%) and half inhibition concentration cI,50 were obtained, respectively. Experimental results show that the two kinds of complexes RE(Hsal)2•(tch)•2H2O possess the biphacial biological effect and Hormesis effect, which stimulate the growth of Escherichia coli at lower concentrations, but inhibit the growth at higher concentrations. Inhibitory effect of Sm(Hsal)2•(tch)•2H2O (cI,50＝1.62 mg•L－1) is stronger than that of La(Hsal)2•(tch)•2H2O (cI,50＝7.60 mg•L－1).