微酸性电解水对家蚕黑胸败血芽孢杆菌的杀灭效果及机制研究

Sterilization Effect and Mechanism of Slightly Acidic Electrolyzed Water on Bacillus bombyseptieus

微酸性电解水作为一种安全、高效、广谱的新型消毒剂,具有制备简单、成本低、使用后无残留、对人体无毒无害等优点。研究微酸性电解水对家蚕黑胸败血芽孢杆菌的杀灭效果及其杀菌机制,为其在蚕桑生产中的应用奠定基础。体外抑菌试验结果表明,有效氯质量浓度为40 mg/L、pH 5.5、氧化还原电位(ORP)为1100 mV的微酸性电解水处理5 min即可全部杀灭家蚕黑胸败血芽孢杆菌。生物学试验结果表明,该电解水对家蚕黑胸败血芽孢杆菌处理5 min后,家蚕黑胸败血芽孢杆菌的灭活率达到90%;处理15 min时,灭活率为100%。经微酸性电解水处理后,家蚕黑胸败血芽孢杆菌的外部形态发生改变,菌体膨胀、逐渐伸长,之后出现孔洞,最后菌体破裂、死亡;胞外电导率、可溶性蛋白含量和可溶性糖含量逐渐增加;菌体DNA发生降解。试验结果表明微酸性电解水主要通过破坏家蚕黑胸败血芽孢杆菌细胞外部形态,改变细胞膜通透性,导致细胞内容物外渗,DNA结构受到破坏,达到杀菌目的。

As a safe,efficient and broad-spectrum new disinfectant,slightly acidic electrolyzed water(SAEW)has the advantages of simple preparation,low cost,no residue after use,and being non-toxic and harmless to human body.In order to provide basis for the application of SEAW in sericultural production,sterilization effect and mechanism of SAEW on Bacillus bombyseptieus were studied in this paper.In vitro antimicrobial test showed that SAEW with available chlorine mass concentrations of 40 mg/L,pH of 5.5,oxidation-reduction potential(ORP)of 1100 mV could kill Bacillus bombyseptieus in 5 min.The results of biological experiment showed that the inactivation rate of Bacillus bombyseptieus reached 90%after being treated with SAEW for 5 min,and the inactivation rate of Bacillus bombyseptieus was 100%for 15 min.After treated with SAEW,the external morphology of Bacillus bombyseptieus changed,the cell expanded and gradually elongated,some holes appeared,and finally the cell ruptured and died.Meanwhile,the extracellular conductivity,soluble protein content and soluble sugar content increased rapidly.The cell DNA was severely degraded.The results showed that SAEW could damage the external morphology and the permeability of the cell membrane of Bacillus bombyseptieus,leading to the leakage of cell contents,the destruction of DNA structure,and finally death of cell.