Fast and effective inactivation of Bacillus atrophaeus endospores using light-activated derivatives of vitamin B2

• DOI: 10.1039/c4pp00285g
• Publication Date: 2014-11-11T11:04:08Z
• Authors: Anja Eichner; Anita Gollmer; Andreas Späth; Wolfgang Bäumler; Johannes Regensbu...; Burkhard König; Tim Maisch
• Keywords: Spores, Bacterial; 0301 basic medicine; ddc:610; 0303 health sciences; Photosensitizing Agents; Dose-Response Relationship, Drug; Light; Singlet Oxygen; Cell Survival; Polyethylene Terephthalates; ddc:540; Riboflavin; Photodynamic inactivation; 610 Medizin; Water; Bacillus; Cell Line; 03 medical and health sciences; Anti-Infective Agents; Microscopy, Electron, Transmission; Flavins; 540 Chemie; Humans

Abstract Highly resistant endospores may cause severe problems in medicine as well the food and packaging industries. We found that bacterial can be inactivated quickly with reactive oxygen species (ROS) were generated by a new generation of flavin photosensitizers. Flavins like natural compound vitamin B2 are already known to produce ROS but they show poor antimicrobial photodynamic killing efficacy due lack positive charges. Therefore we synthesized photosensitizers have one (FLASH-01a) or eight (FLASH-07a) charges hence attach negatively charged surface endospores. In this study used standardized Bacillus atrophaeus (ATCC 9372) biological surrogate model for proof-of-concept inactivation experiments using FLASH-01a FLASH-07a. After incubation spores different concentrations, derivatives excited blue light at dose 70 J cm −2 . The was investigated either suspension after attachment polyethylene terephthalate (PET) surfaces. Incubation suspended Millipore water 4 mM 10 seconds irradiation caused biologically relevant decrease spore survival 3.5 log orders. Using FLASH-07a under same conditions achieved 4.4 Immobilized on PET surfaces efficiently killed 7.0 orders 8 total treatment time (incubation + irradiation) short 20 seconds. results evidence fastly effectively generations useful industrial medical applications future.