Microbial photoinactivation by 470 nm radiation: an investigation into the underlying photobiological mechanism

  title={Microbial photoinactivation by 470 nm radiation: an investigation into the underlying photobiological mechanism},
  author={Katharina Hoenes and Kerstin Wild and Julian Schmid and Barbara Spellerberg and Martin Hessling},
The photoinactivation properties of 405 (violet) and 470 nm (blue) light have been studied by many research groups within the last few years. Both wavelengths are capable of disinfecting bacteria and fungi, with 405 nm radiation being more efficient. The basic photoinactivation mechanism is understood for 405 nm. Violet light is absorbed by endogenous porphyrins that act as photosensitizers and generate reactive oxygen species, subsequently destroying the microorganisms from within. The… 
405 nm and 450 nm Photoinactivation of Saccharomyces cerevisiae
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Results suggest that the excitation of endogenous porphyrins and subsequent accumulation of singlet oxygen could partially explain the 405‐nm light‐mediated photoinactivation of B. cinerea.
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Eradication of Propionibacterium acnes by its endogenic porphyrins after illumination with high intensity blue light.
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Blue light for infectious diseases: Propionibacterium acnes, Helicobacter pylori, and beyond?
New photosensitizers for photodynamic therapy.
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Sporicidal Effects of High‐Intensity 405 nm Visible Light on Endospore‐Forming Bacteria
The demonstration that visible light of 405 nm can induce a bactericidal effect against endospores is significant, and could have potential for incorporation into decontamination methods for the removal of bacterial contamination including endospore.