Bacterial resistance has led to the spread of bacterial infections such as chronic wound infections. Finding solutions for combating resistant bacteria in chronic wounds such as Staphylococcus aureus and Pseudomonas aeruginosa became an attractive theme among researchers. P. aeruginosa is a gram negative opportunistic human pathogenic bacterium that is difficult to treat due to its high resistance to antibiotics. S. aureus (gram negative bacterium) also has a high antibiotic resistance, so that it is resistant to vancomycin (VRSA), tetracycline, fluoroquinolones and beta-lactam antibiotics including penicillin and methicillin (MRSA). In particular, S. aureus and P. aeruginosa have intrinsic and acquired antibiotic resistance, making the clinical management of infection a real challenge, especially in patients with comorbidities. aPDT can be proposed as a new method in the treatment of multi-drug resistant bacteria in chronic wound infection conditions. In this study, the effect of saponin (100 μg/mL) on photodynamic inactivation on planktonic and biofilm forms of P. aeruginosa (ATCC 27853) and S. aureus (ATCC 25923) strains and on Human Dermal Fibroblast (HDF) cells was investigated. Methylene blue (MB) was used as photosensitizer (0, 10, 50, 100 μg/mL). The light source was a red LED source (660 nm; power density: 20 mW/cm²) which is related to the maximum absorption of MB. The results showed that the use of saponin in combination with MB-aPDT (Methylene Blue-antibacterial photodynamic therapy) reduces the phototoxic activity of MB due to decreasing the monomer form of MB. This result was obtained by spectrophotometric study. Also, the result of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay showed that 8 min of irradiation (660 nm) at 10 μg/mL concentration of alone MB had the lowest phototoxic effect on HDF cells. Due to reduced phototoxic properties of MB in this method, detergents containing saponins not recommended to applied at the same time with MB-aPDT in wound infection area.

细菌耐药性导致细菌感染的传播，例如慢性伤口感染。寻找对抗慢性伤口中的耐药细菌（例如金黄色葡萄球菌和铜绿假单胞菌）的解决方案成为研究人员中一个有吸引力的主题。铜绿假单胞菌是一种革兰氏阴性机会性人类致病菌，由于对抗生素具有高度耐药性而难以治疗。金黄色葡萄球菌（革兰氏阴性菌）还具有很高的抗生素耐药性，因此它对万古霉素（VRSA）、四环素、氟喹诺酮类以及包括青霉素和甲氧西林（MRSA）在内的β-内酰胺类抗生素具有耐药性。特别是，金黄色葡萄球菌和铜绿假单胞菌具有内在的和获得性的抗生素耐药性，使得感染的临床管理成为真正的挑战，特别是对于患有合并症的患者。 aPDT 可以作为治疗慢性伤口感染条件下的多重耐药细菌的新方法。在本研究中，研究了皂苷 (100 μg/mL) 对铜绿假单胞菌(ATCC 27853) 和金黄色葡萄球菌(ATCC 25923) 菌株以及人真皮成纤维细胞 (HDF) 细胞的浮游和生物膜形式的光动力失活的影响。使用亚甲蓝（MB）作为光敏剂（0、10、50、100 μg/mL）。光源为红色LED光源(660nm；功率密度：20mW/cm ² )，其与MB的最大吸收有关。结果表明，皂苷与MB-aPDT（亚甲蓝抗菌光动力疗法）联合使用，由于减少了MB的单体形式，从而降低了MB的光毒性活性。该结果是通过分光光度研究获得的。此外，MTT（3-（4,5-二甲基噻唑-2-基）-2,5-二苯基-2H-四唑溴化物）测定结果表明，在 10 μg/mL 浓度下照射 8 分钟（660 nm）单独的MB对HDF细胞的光毒性作用最低。由于该方法中MB的光毒性降低，因此不建议在伤口感染区域与MB-aPDT同时使用含有皂苷的清洁剂。