Rose bengal has been used in the diagnosis of ophthalmic disorders and liver function, and has been studied for the treatment of solid tumor cancers. To date, the antibacterial activity of rose bengal has been sporadically reported; however, these data have been generated with a commercial grade of rose bengal, which contains major uncontrolled impurities generated by the manufacturing process (80–95% dye content). A high-purity form of rose bengal formulation (HP-RBf, >99.5% dye content) kills a battery of Gram-positive bacteria, including drug-resistant strains at low concentrations (0.01–3.13 µg/mL) under fluorescent, LED, and natural light in a few minutes. Significantly, HP-RBf effectively eradicates Gram-positive bacterial biofilms. The frequency that Gram-positive bacteria spontaneously developed resistance to HP-RB is extremely low (less than 1 × 10−13 ). Toxicity data obtained through our research programs indicate that HP-RB is feasible as an anti-infective drug for the treatment of skin and soft tissue infections (SSTIs) involving multidrugresistant (MDR) microbial invasion of the skin, and for eradicating biofilms. This article summarizes the antibacterial activity of pharmaceutical-grade rose bengal, HP-RB, against Gram-positive bacteria, its cytotoxicity against skin cells under illumination conditions, and mechanistic insights into rose bengal’s bactericidal activity under dark conditions.
Bibliographical noteFunding Information:
Acknowledgments: The authors M.K. and K.M. are grateful to Provectus Biopharamceuticals for financial support.
The MraY inhibitor and some bacteria and mammalian cell lines used in this study were generated or acquired by the NIH-funded program (R01GM114611).The authors M.K. and K.M. are grateful to Provectus Biopharamceuticals for financial support.
© 2022 by the authors. Licensee MDPI, Basel, Switzerland.
- Antibacterial activity
- Drugresistant gram-positive pathogens
- High-purity form of rose bengal (HP-RB)
- Methicillin-resistant Staphylococcus aureus
- Multidrug-resistant bacteria
- Rose bengal (RB)
- Vancomycin resistant Enterococcus faecium
- Whole genome analyses
PubMed: MeSH publication types
- Journal Article