冷培养对金属化合物枯草杆菌致变试验结果的影响

目的：研究枯草杆菌芽孢重组修得试验中增加冷培养对金属化合物和间接致变物DNA损伤试验的影响。方法：比较直接培养法与增加4℃ 24h冷培养对测试结果的作用。观察指标：最小抑菌浓度（MIC）和敏感性。结果：增加冷培养对大多数金属化合物测试结果无影响，而对K2Cr2O4、CoCl2、CoSO4及2种间接致突变物2-AF、AFB反而提高了MIC，降低了敏感性。此结果与Kada的报道不尽一致，对其原因加以探讨。结论：枯草杆菌芽孢重组修复试验增加冷培养，降低了部分金属致突变物和间接致变物敏感性。

The Effect of Spore Rec-assay with B.Subtilis for Cold Incubation

To study the effect of spore rec assay with B.subtilis with an additional cold incubation to determine the DNA damage of metal and indirect mutagens. The mininal inhibitory concentration(MIC) and sensitivity were compared between direct incubation and additional cold incubation in spore rec assay. Adding cold incubation,the MIC is risen and the sensitivity decreased when three metal componds K 2Cr 2O 4,CoCl 2,CoSO 4 and two indirect mutagens 2AF,AFB 1 were tested,but 5 metal compounds such as K 2Cr 2O 7,CdSO 2,ZnSO 4,Zn(CH 2COO) 2,G 024 and indirect mutagen 2 AA showed no significant changes. Other 7 metal compounds Co(NO 3) 2,MnSO 4,FeCl 3,TiSO 4,NiSO 4,Ni 2O 2 and ZrOCl 3 showed negative reaction using either cold incubation or direct incubation. Conclusion] It is suggested that adding cold incubation in spore rec assay is not useful,it may rise MIC and diminishe sensitivity for a few metal and indirect mutagens.