New trends in photobiology bactericidal effects of photoactivated porphyrins — An alternative approach to antimicrobial drugs

Malik, Zvi; Hanania, J.; Nitzan, Yeshayau

doi:10.1016/1011-1344(90)85044-w

Cited by 307 publications

(223 citation statements)

References 41 publications

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“…In previous studies with porphyrinoid photosensitizers, Gram-positive bacteria were inhibited after irradiation, but the activity against Gram-negative bacteria was limited. [29][30][31] In this study, we have obtained a low activity of chl-e6 and chl-e6H against a Gram-negative microorganism, and higher activity in a Gram-positive microorganism. Previous studies show that it is easier to inactivate Grampositive than Gram-negative bacteria, which can be explained by the electronic charges of the cell walls.…”

Section: Photodynamic Inactivation Of Microorganismsmentioning

confidence: 99%

Photobiological characteristics of chlorophyll a derivatives as microbial PDT agents

Uliana

Pires

Pratavieira

et al. 2014

Photochem Photobiol Sci

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a Chlorin-e6 (chl-e6) and a hydrogenated derivative (chl-e6H) were semi-synthesized, and their photophysical properties and photodynamic activity against Escherichia coli, Staphylococcus aureus and Candida albicans evaluated. Methyl pheophorbide-a (Mepheo-a) was obtained from S. maxima using methanolic extraction with acid catalysis (CH 3 OH-H 2 SO 4 ). Chlorin-e6 was prepared from Mepheo-a by basic hydrolysis with H 2 O-acetone and NaOH. Hydrogenated Chlorin-e6 was synthesized by a similar procedure starting from the hydrogenated methyl pheophorbide-a (Mepheo-aH). Photophysical studies were performed in order to determine the singlet oxygen quantum yield of chl-e6H which is higher than that of chl-e6. The microorganism inactivation of chl-e6 and chl-e6H was investigated at two concentrations and three fluence levels. Both chl-e6 and chl-e6H showed microorganism inactivation against Gram-positive bacteria and a fungus.

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Section: Photodynamic Inactivation Of Microorganismsmentioning

confidence: 99%

Photobiological characteristics of chlorophyll a derivatives as microbial PDT agents

Uliana

Pires

Pratavieira

et al. 2014

Photochem Photobiol Sci

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“…It was stated in previous studies that phototoxicity in the presence of exogenous photosensitizers such as Rose Bengal, Erythrosine, Toluidine blue, Methylene blue and many other photosensitizers increases upon light irradiation, caused by a series of energy transfers from light energy to molecular energy, thereby generating ROS and singlet oxygen causing cytotoxicity to the bacterial cells [1,11,13,30]. Studies also indicate that the presence of endogenous bacterial porphyrins act as photosensitizers causing bacterial cell death due to similar photochemical reactions [3,23,42,44]. Presence of a fluorophore or a photosensitizing compound within the absorption spectrum of Violet-blue light in the bacteria will absorb the light energy of the photons and undergo a cascade of reactions mediating photoinactivation.…”

Section: Discussionmentioning

confidence: 98%

Photo Inactivation of Streptococcus mutans Biofilm by Violet-Blue light

et al. 2016

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Among various preventive approaches, non-invasive phototherapy/photodynamic therapy is one method used to control oral biofilm. Studies indicate that light at specific wavelengths has a potent antibacterial effect. The objective of this study was to determine the effectiveness of violet-blue light at 380-440 nm to inhibit biofilm formation of Streptococcus mutans or kill S. mutans. S. mutans UA159 biofilm cells were grown for 12-16 h in 96-well flat-bottom microtiter plates using Tryptic Soy broth (TSB) or TSB with 1% sucrose (TSBS). Biofilm was irradiated with violet-blue light for 5 min. After exposure, plates were re-incubated at 37°C for either 2 or 6 h to allow the bacteria to recover. A crystal violet biofilm assay was used to determine relative densities of the biofilm cells grown in TSB, but not in TSBS, exposed to violet-blue light. The results indicated a statistically significant (p < 0.05) decrease compared to the nontreated groups after the 2 or 6h recovery period. Growth rates of planktonic and biofilm cells indicated a significant reduction in the growth rate of the violet-blue light-treated groups grown in TSB and TSBS. Biofilm viability assays confirmed a statistically significant difference between Violet-blue light-treated and non-treated groups in TSB and TSBS. Visible Violet-blue light of the electromagnetic spectrum has the ability to inhibit S. mutans growth and reduce the formation of S. mutans biofilm. This in-vitro study demonstrated that Violet-blue light has the capacity to inhibit S. mutans biofilm formation. Potential clinical applications of light therapy in the future remain bright in preventing the development and progression of dental caries.

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“…The positively charged phthalocyanines, especially, have been studied regarding their bactericidal effect to G-bacteria (Merchat et al, 1996;Minnock et al, 1996). Porphyrins have also been shown to be effective sensitizers for the inactivation of microbes (Malik et al, 1990;Merchat et al, 1996;Reddi et al, 2002). Higher sensitivity of cyanobacteria to ROS, contrary to green algae, is known from several studies on hydrogen peroxide, which also belongs to the group of ROS (Barroin and Feuillade, 1986).…”

Section: Introductionmentioning

confidence: 99%

Photodynamic therapy against cyanobacteria

Drábková

Maršálek

Admiraal

2007

Environmental Toxicology

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This study explores the use of photosensitizers and reactive oxygen species (ROS) to limit growth of cyanobacteria. We chose 12 phthalocyanines, tetraphenol porphyrine, and methylene blue as compounds producing singlet oxygen. Hydrogen peroxide was chosen as another source of ROS. These compounds were tested using algal toxicity tests in microplates on three cultures of green algae (Pseudokirchneriella subcapitata, Scenedesmus quadricauda, and Chlorella kessleri) and on three cultures of cyanobacteria (Synechococcus nidulans, Microcystis incerta, and Anabaena sp.). Results indicate that photosensitizers and singlet oxygen could be highly toxic for some selected phytoplankton species. Green alga Scenedesmus quadricauda was highly sensitive (EC50 ¼ 0.07 mg/L) to compounds producing singlet oxygen, although it was not sensitive to hydrogen peroxide, which was about 10 times more toxic for cyanobacteria. We conclude that the compounds producing hydroxyl radical species seems to be more promising to treat cyanobacterial blooms than the compounds producing the singlet oxygen. # 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 112-115, 2007.

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New trends in photobiology bactericidal effects of photoactivated porphyrins — An alternative approach to antimicrobial drugs

Cited by 307 publications

References 41 publications

Photobiological characteristics of chlorophyll a derivatives as microbial PDT agents

Photobiological characteristics of chlorophyll a derivatives as microbial PDT agents

Photo Inactivation of Streptococcus mutans Biofilm by Violet-Blue light

Photodynamic therapy against cyanobacteria

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