title: [Bactericidal effect of soybean peroxidase-hydrogen peroxide-potassium iodide system].
abstract: OBJECTIVE
  To study the bactericidal effect and the possible mechanisms of the three components system [soybean peroxidases (SBP)-hydrogen peroxide (H2O2)-potassium iodide (KI), SBP-H2O2-KI].
  
  
  METHODS
  The inhibition and bactericidal effect of SBP-H2O2-KI system to bacteria was detected by OD600 and the number of live bacteria (CFU). The sensitivity was tested by comparing the minimum inhibitory concentration (MIC) of bacterial cultures before and after cultured under sub-lethal dose of SBP-H2O2-KI system. Oxidizing activity groups were detected with physical and chemical methods in order to explain the bactericidal mechanisms of SBP-H2O2-KI system.
  
  
  RESULTS
  SBP-H2O2-KI ternary system had rapid and high efficient bactericidal effect to a variety of bacterial strains in just several minutes. The MICs had no significant changes when bacterial cultures continuously cultured in sub-lethal dose of SBP-H2O2-KI system, and no resistance/tolerance mutant strains could be isolated from them. Both physical and chemical test results showed that no hydroxyl radical produced in SBP- H2O2-KI reaction system, chemical test results showed that no superoxide anion but a singlet oxygen and iodine produced in SBP-H2O2-KI reaction system.
  
  
  CONCLUSIONS
  These results suggested that singlet oxygen and iodine or the iodine intermediate state may possible be the main sterilization factors for SBP-H2O2-KI system, and hydroxyl radical and superoxide anion not. In addition, the both characteristics of SBP-H2O2-KI system: rapid and high efficient bactericidal effect, and bacteria difficultly resisting to it, indicated it would have a good potential application in medical and plant protection area.
authors: State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan 250100, China. jinjianling@sdu.edu.cn
authors: Jianling
authors: J
authors: Jin
authors: Weican
authors: W
authors: Zhang
authors: Yu
authors: Y
authors: Li
authors: Yue
authors: Y
authors: Zhao
authors: Fei
authors: F
authors: Wang
authors: Peiji
authors: P
authors: Gao