氨基酸碘对白色念珠菌的杀菌机理研究

STUDY ON MECHANISM OF KILLING Candida albicans BY AMINO-ACID IODINE

目的研究氨基酸碘杀菌效果及其作用机理，为其应用于实践提供依据。方法采用悬液定量杀菌试验，透射电镜和生化检测等方法进行了实验室观察。结果含有效碘200mg／L的氨基酸碘溶液作用3—20min，对悬液内白色念珠菌的平均杀灭率范围为99．91％～99．96％；含有效碘400mg／L该消毒液作用3min，对白色念珠菌的杀灭率可达到100％。经氨基酸碘处理的白色念珠菌外层质膜电子密度明显降低，继而菌体形态呵出现轻度不规则，细胞质中细胞器和核质结构形态混乱。氨基酸碘作用可使白色念珠菌膜蛋白含量减少，细菌碱性磷酸酶和琥珀酸脱氢酶渗出，且琥珀酸脱氢酶活性有所抑制；细菌核酸无降解发生，但有少量交联物生成。结论氨基酸碘对白色念珠菌杀灭作用较强。氨基酸碘可使细菌膜通透性明显增加，膜结构蛋白降解，胞质及蛋白酶渗出，琥珀酸脱氢酶活性显著降低，少量细菌核酸发生交联反应。

Objective To study the germicidal efficacy of amino - acid iodine, and its germicidal mechanism in order to provide the basis for its application to practice. Methods Suspension quantitative germicidal test, transmission electronmicroscopy and biochemical examination methods were used to carry out laboratory observation. Results The average killing rates of Candida albicans in suspension exposed to the amino - acid iodine solution containing available iodine 200 mg/L for 3 - 20 min ranged 99.91% - 99.96%. The killing rate of C. albicans exposed to the disinfectant solution containing available iodine 400 mg/L for 3 min could attain 100%. The electron density of the outer plasma membrane of C. albicans treated with amino - acid iodine decreased obviously and subsequently, the shape of the thallus became slightly irregular and the appearance of organelle and structure of nuclein became jumbly. Exposure to amino - acid iodine could reduce membrane protein content of C. albicans , cause leakage of bacterial alkaline phosphatase and succinic dehydrogenase, inhibition of activity of succinic dehydrogenase, no degradation of nucleic acids and formation of a little amount of cross - linking products. Conclusion Amino - acid iodine has strong killing effect on C. albicans. It can obviously increase the permeability of the fungal membrane, and cause degradation of membrane structure protein, leakage of cytoplasm and proteinase, obvious decrease in activity of succinic dehydrogenase and cross - linking reaction of a little amount of fungal nucleic acid.