期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2016
卷号：113
期号：48
页码：13612-13617
DOI：10.1073/pnas.1611193113
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceBacteria are increasingly becoming resistant to antibiotics; therefore, other means must be found for their inactivation. Efficient inactivation of bacteria cannot be achieved simply by increasing the dose because of toxicity limitation. Therefore, it is critical to search for a combination of agents, within a safe dose, that is more effective in killing bacteria than agents reacting alone. Here, we show that the combination of methylene blue (MB) and silver nitrate can be up to three orders of magnitude more effective in killing bacteria than the two agents reacting alone against bacteria. This synergistic mechanism is due to silver ion increasing the penetration of MB into the bacteria interior, allowing photogenerated single oxygen to react with DNA and prevent replication. In this paper we describe the antibacterial effect of methylene blue, MB, and silver nitrate reacting alone and in combination against five bacterial strains including Serratia marcescens and Escherichia coli bacteria. The data presented suggest that when the two components are combined and react together against bacteria, the effects can be up to three orders of magnitude greater than that of the sum of the two components reacting alone against bacteria. Analysis of the experimental data provides proof that a synergistic mechanism is operative within a dose range when the two components react together, and additive when reacting alone against bacteria.
关键词：bacteria ; synergistic effect ; methylene blue ; silver ions
