Figueiredo-Godoi Lívia M A, Garcia Maíra T, Pinto Juliana G, Ferreira-Strixino Juliana, Faustino Eliseu Gabriel, Pedroso Lara Luise Castro, Junqueira Juliana C
Institute of Science and Technology (ICT), São Paulo State University (Unesp), São José dos Campos, São Paulo 12245-000, Brazil.
Photobiology Applied to Health (Photobios), University of Vale of Paraiba/UNIVAP, São José dos Campos, São Paulo 12244-000, Brazil.
Antibiotics (Basel). 2022 May 4;11(5):619. doi: 10.3390/antibiotics11050619.
Antimicrobial photodynamic therapy (aPDT) is considered a promising alternative strategy to control infections. In this study, we evaluated the action of aPDT mediated by a new photosensitizer derivative from chlorin e-6 (Fotoenticine-FTC) on comparing its effects with methylene blue (MB). For this, aPDT was applied on in planktonic growth, biofilms, and burn infections in . The absorption of FTC and MB by bacterial cells was also evaluated using microscopic and spectrophotometric analysis. The results of planktonic cultures showed that aPDT reduced the number of viable cells compared to the non-treated group for the reference and multidrug-resistant strains. These reductions varied from 1.4 to 2 log CFU for FTC and from 2 log CFU to total inhibition for MB. In biofilms, aPDT with MB reduced 3.9 log CFU of , whereas FTC had no effect on the cell counts. In , only MB-mediated aPDT had antimicrobial activity on burn injuries, increasing the larvae survival by 35%. Both photosensitizers were internalized by bacterial cells, but MB showed a higher absorption compared to FTC. In conclusion, MB had greater efficacy than FTC as a photosensitizer in aPDT against .
抗菌光动力疗法（aPDT）被认为是控制感染的一种有前景的替代策略。在本研究中，我们评估了一种由二氢卟吩e-6（Fotoenticine-FTC）衍生的新型光敏剂介导的aPDT的作用，并将其效果与亚甲蓝（MB）进行比较。为此，将aPDT应用于浮游生长、生物膜以及烧伤感染模型。还使用显微镜和分光光度分析评估了细菌细胞对FTC和MB的摄取。浮游培养结果表明，与未处理组相比，aPDT降低了参考菌株和多重耐药菌株的活菌数量。FTC使活菌数量减少了1.4至2个对数CFU，而MB则使活菌数量减少了2个对数CFU直至完全抑制。在生物膜中，MB介导的aPDT使某菌的CFU减少了3.9个对数，而FTC对细胞计数没有影响。在烧伤感染模型中，只有MB介导的aPDT对烧伤具有抗菌活性，使幼虫存活率提高了35%。两种光敏剂均被细菌细胞内化，但与FTC相比，MB的摄取更高。总之，在针对某菌的aPDT中，MB作为光敏剂比FTC具有更高的疗效。
