Abstract
Purpose: :
Ultraviolet light (UV) and riboflavin have been used to treat corneal ulcers with apparent favorable results. An anti-collagenase effect, a strengthening of collagen, or an antibacterial effect have all been invoked as possible mechanisms for therapeutic benefit. We test the anti-bacterial action of riboflavin, UV-light, and the combination of riboflavin and UV-light on Staph aureus, MRSA, and Pseudomonas aeruginosa.
Methods: :
30 agar plates with quality controlled ATCC 25923 Staph aureus overlays were used. 10 plates were exposed to riboflavin (0.1% solution in dextran), 10 plates were exposed to UV-light (365nm) for 30 minutes, and 10 plates were exposed to a combination of riboflavin and UV-light for 30 minutes. 15 agar plates with quality controlled ATCC 43300 MRSA and 15 plates with quality controlled ATCC 27853 Pseudomonas aeruginosa were tested. 5 plates of each group were exposed to riboflavin, 5 plates of each group were exposed to UV-light for 30 minutes, and 5 plates of each group were exposed to a combination of riboflavin and UV-light for 30 minutes.All plates were incubated for 24 hours, then analyzed.
Results: :
Plates exposed to riboflavin alone showed no bacterial death. Staph aureus and MRSA plates exposed to UV-light alone showed no bacterial death. 3 of 5 Pseudomonas plates exposed to UV-light alone showed no bacterial death; 2 of 5 Pseudomonas plates exposed to UV-light alone showed minimal inhibition. All plates exposed to a combination of riboflavin and UV-light showed bacterial death.
Conclusions: :
Riboflavin combined with UV-light has antimicrobial activity against Staph aureus, MRSA, and Pseudomonas aeruginosa.
Keywords: bacterial disease • antibiotics/antifungals/antiparasitics • anterior segment