Antimicrobial effect of rutin as flavonoid compound and photodynamic inactivation on Pseudomonas aeruginosa as common bacteria in chronic wounds

Purpose: P. aeruginosa has both intrinsic and acquired antibiotic resistance, making clinical management of infection a real challenge, particularly in patients with comorbidity. Antibacterial photodynamic therapy (aPDT) has increasing attention for its potential to effectively kill multidrug-resistant pathogenic bacteria and also its low tendency to induce drug resistance that bacteria can rapidly develop against traditional antibiotic therapy. The antimicrobial effect of aPDT is based on the principle that visible light activates a non-toxic molecule, photosensitizer (PS), resulting in generation of reactive oxygen species that kill bacteria. The most important role of aPDT is in the treatment of chronic wound associated microbial biofilms. Rutin as a flavonoid compound which derived from plants such as wheat, apple and tea has many properties like antibacterial activity. In this study, we investigated the antimicrobial effect of rutin and photodynamic inactivation on Pseudomonas aeruginosa.Materials and methods: After performing MIC assay (to measure minimum inhibitory concentration) and MTT assay (to evaluate methylene blue toxicity), the effect of aPDT at 660nm and pretreatment or post treatment with rutin on bacteria in the planktonic form, prevention of biofilm formation, and the ability to degrade biofilm were investigated.Results: The results showed that by combination of rutin with aPDT (5min, 660nm) and the use of methylene blue as a photosensitizer, there is a reduction in the number of bacteria in planktonic condition, bacterial biofilm production and also enhance in destruction of the biofilm.Conclusions: Combination therapy with rutin and aPDT could be suggested as novel approach in the treatment of multi drug resistant bacteria in chronic ulcer condition

Keywords:

Chronic ulcer , Photodynamic therapy , Pseudomonas aeruginosa , Multidrug resistant bacteria