Fewer antibiotics are available for effective management of bacterial infections to date owing to increasing multiple-drug resistance (MDR). Here, we expand our early success in combination of 405 nm blue light irradiation with phenolic compounds to sufficiently kill blue light-refractory MDR Escherichia coli (E. coli). p-Toluquinone (p-TQ) alongside blue light inactivated 7.3 log₁₀ E. coli within 6 min, whereas either alone was totally ineffective. A similar killing efficacy was attained with four other pathogens commonly seen in hospital-acquired infections and Enterococcus faecalis (Ef) that don't produce porphyrins-like molecules. The combinatory therapy prevented recurrence of E. coli infection in skin scratch wounds of murine. The bactericidal activity was ascribed to reactive oxygen species (ROS) generation triggered by blue light-mediated excitation of p-TQ, which is less likely to induce resistance because of multi-targeted and non-specific nature of ROS. Remarkably, toxic p-TQ became harmless to mammalian cells after brief exposure to blue light while retaining its bactericidal activity. The opposite effect of blue light on p-TQ activity unravels a novel, simple strategy to detoxify p-TQ and its combination with blue light as a safe and efficacious bactericidal modality for managing MDR bacterial infections.

由于多药耐药性（MDR）的增加，迄今为止可用于有效管理细菌感染的抗生素越来越少。在这里，我们扩大了我们早期的成功，将 405 nm 蓝光照射与酚类化合物相结合，以充分杀死蓝光难治的 MDR大肠杆菌（大肠杆菌）。对甲苯醌 (p-TQ) 与蓝光一起在 6 分钟内灭活 7.3 log ₁₀ 大肠杆菌，而单独使用任何一种都完全无效。医院获得性感染中常见的其他四种病原体和不产生卟啉样分子的粪肠球菌( Ef ) 也获得了类似的杀灭效果。联合治疗预防复发小鼠皮肤抓伤处的大肠杆菌感染。杀菌活性归因于由蓝光介导的 p-TQ 激发引发的活性氧 (ROS) 生成，由于 ROS 的多靶点和非特异性性质，因此不太可能诱导耐药性。值得注意的是，有毒的 p-TQ 在短暂暴露于蓝光后对哺乳动物细胞无害，同时保留了其杀菌活性。蓝光对 p-TQ 活性的相反影响揭示了一种新的、简单的解毒 p-TQ 的策略，并将其与蓝光组合作为管理 MDR 细菌感染的安全有效的杀菌方式。