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Ndlovu KS, Moloto MJ, Sekhosana KE, Nkambule TTI, Managa M. Porphyrins developed for photoinactivation of microbes in wastewater. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:11210-11225. [PMID: 36515881 DOI: 10.1007/s11356-022-24644-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 12/04/2022] [Indexed: 06/17/2023]
Abstract
Photodynamic antimicrobial chemotherapy (PACT) is extensively studied as a strategic method to inactivate pathogenic microbes in wastewater for addressing the limitations associated with chlorination, ozonation, and ultraviolet irradiation as disinfection methods, which generally promote the development of resistant genes and harmful by-products such as trihalomethanes. PACT is dependent on photons, oxygen, and a photosensitizer to induce cytotoxic effects on various microbes by generating reactive oxygen species. Photosensitizers such as porphyrins have demonstrated significant microbial inactivation through PACT, hence now explored for wastewater phototreatment. This review aims to evaluate the efficacy of porphyrins and porphyrin-conjugates as photosensitizers for wastewater photoinactivation. Concerns relating to the application of photosensitizers in water treatment are also evaluated. This includes recovery and reuse of the photosensitizer when immobilized on solid supports.
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Affiliation(s)
- Knowledge Siyabonga Ndlovu
- Institute for Nanotechnology and Water Sustainability (iNanoWS), Florida Campus, College of Science, Engineering and Technology, University of South Africa, Johannesburg, 1710, South Africa
| | - Makwena Justice Moloto
- Institute for Nanotechnology and Water Sustainability (iNanoWS), Florida Campus, College of Science, Engineering and Technology, University of South Africa, Johannesburg, 1710, South Africa
| | - Kutloano Edward Sekhosana
- Institute for Nanotechnology and Water Sustainability (iNanoWS), Florida Campus, College of Science, Engineering and Technology, University of South Africa, Johannesburg, 1710, South Africa
| | - Thabo Thokozani Innocent Nkambule
- Institute for Nanotechnology and Water Sustainability (iNanoWS), Florida Campus, College of Science, Engineering and Technology, University of South Africa, Johannesburg, 1710, South Africa
| | - Muthumuni Managa
- Institute for Nanotechnology and Water Sustainability (iNanoWS), Florida Campus, College of Science, Engineering and Technology, University of South Africa, Johannesburg, 1710, South Africa.
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Sengupta D, Rai M, Hoque Mazumdar Z, Sharma D, Malabika Singha K, Pandey P, Gaur R. Two cationic meso-thiophenium porphyrins and their zinc-complexes as anti-HIV-1 and antibacterial agents under non-photodynamic therapy (PDT) conditions. Bioorg Med Chem Lett 2022; 65:128699. [PMID: 35341921 DOI: 10.1016/j.bmcl.2022.128699] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/16/2022] [Accepted: 03/23/2022] [Indexed: 11/02/2022]
Abstract
The anti-HIV-1 and antimicrobial activities of novel cationic meso-thiophenium porphyrins and their zinc-complex are reported under in vitro non-photodynamic (PDT) conditions. While all the cationic porphyrins led to the inhibition of de novo virus infection, the Zn(II)-complexes of T2(OH)2M (A2B2-type) and T(OH)3M (AB3-type) displayed potent inhibition of HIV-1 entry with T2(OH)2MZn displaying maximal anti-HIV activity. The Zinc complex of both the thiophenium porphyrins T2(OH)2M and T(OH)3M also depicted antibacterial activities against Escherichia coli (ATCC 25922) and more prominently against Staphylococcus aureus (ATCC 25923). Again, the antibacterial activity was more potent for T2(OH)2MZn. Our study highlighted that the presence of two thiophenium groups at the meso-positions of the A2B2-type porphyrins along with zinc strongly enhanced anti-HIV and antimicrobial properties of these novel thiophenium porphyrins under non-PDT conditions.
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Affiliation(s)
- Devashish Sengupta
- Department of Chemistry, Assam University, Silchar, Assam 788011, India.
| | - Madhu Rai
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi 110021, India
| | | | - Debdulal Sharma
- Department of Chemistry, Assam University, Silchar, Assam 788011, India
| | - K Malabika Singha
- Department of Microbiology, Assam University, Silchar, Assam 788011, India
| | - Piyush Pandey
- Department of Microbiology, Assam University, Silchar, Assam 788011, India.
| | - Ritu Gaur
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi 110021, India.
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do Prado-Silva L, Brancini GT, Braga GÚ, Liao X, Ding T, Sant’Ana AS. Antimicrobial photodynamic treatment (aPDT) as an innovative technology to control spoilage and pathogenic microorganisms in agri-food products: An updated review. Food Control 2022. [DOI: 10.1016/j.foodcont.2021.108527] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Suciu M, Porav S, Radu T, Rosu MC, Lazar MD, Macavei S, Socaci C. Photodynamic effect of light emitting diodes on E. coli and human skin cells induced by a graphene-based ternary composite. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2021; 223:112298. [PMID: 34474299 DOI: 10.1016/j.jphotobiol.2021.112298] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 01/10/2023]
Abstract
In this paper, the photodynamic effect of a ternary nanocomposite (TiO2-Ag/graphene) on Escherichia coli bacteria and two human cell lines: A375 (melanoma) and HaCaT (keratinocyte) after exposure to different wavelength domains (blue, green or red-Light Emitting Diode, LED) was analyzed. The results obtained through bioassays were correlated with the morphological, structural and spectral data obtained through FT-IR, XPS and UV-Vis spectroscopy, powder X-Ray diffractometry (XRD) and STEM/EDX techniques, leading to conclusions that showed different photodynamic activation mechanisms and effects on bacteria and human cells, depending on the wavelength. The nanocomposite proved a therapeutic potential for blue light-activated antibacterial treatment and revealed a keratinocyte cytotoxic effect under blue and green LEDs. The red light-nanocomposite duo gave a metabolic boost to normal keratinocytes and induced stasis to melanoma cells. The light and nanocomposite combination could be a potential therapy for bacterial keratosis or for skin tumors.
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Affiliation(s)
- Maria Suciu
- National Institute for Research and Development of Isotopic and Molecular Technologies, Donat 67-103 Str., RO-400293 Cluj-Napoca, Romania; Biology and Geology Faculty, Babes-Bolyai University, 5-7 Clinicilor Str, Cluj-Napoca, Romania
| | - Sebastian Porav
- National Institute for Research and Development of Isotopic and Molecular Technologies, Donat 67-103 Str., RO-400293 Cluj-Napoca, Romania
| | - Teodora Radu
- National Institute for Research and Development of Isotopic and Molecular Technologies, Donat 67-103 Str., RO-400293 Cluj-Napoca, Romania
| | - Marcela C Rosu
- National Institute for Research and Development of Isotopic and Molecular Technologies, Donat 67-103 Str., RO-400293 Cluj-Napoca, Romania
| | - Mihaela D Lazar
- National Institute for Research and Development of Isotopic and Molecular Technologies, Donat 67-103 Str., RO-400293 Cluj-Napoca, Romania
| | - Sergiu Macavei
- National Institute for Research and Development of Isotopic and Molecular Technologies, Donat 67-103 Str., RO-400293 Cluj-Napoca, Romania
| | - Crina Socaci
- National Institute for Research and Development of Isotopic and Molecular Technologies, Donat 67-103 Str., RO-400293 Cluj-Napoca, Romania.
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Fayyaz F, Rassa M, Rahimi R. Antibacterial Photoactivity and Thermal Stability of Tetra-cationic Porphyrins Immobilized on Cellulosic Fabrics. Photochem Photobiol 2020; 97:385-397. [PMID: 33152128 DOI: 10.1111/php.13353] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 11/02/2020] [Indexed: 11/28/2022]
Abstract
The thermal stability and photo-bactericidal effect of several tetra-cationic porphyrins and their zinc ion compounds immobilized onto cellulosic fabrics against S. aureus, P. aeruginosa, and E. coli were investigated and compared using a 100 W tungsten lamp. Immobilization of various concentrations of these photosensitizers onto cellulosic fabrics was carried out and characterized by ATR-FT-IR, DRS, TGA, and SEM. Applied cellulosic fabrics with the photosensitizers exhibited remarkable photo-stability, thermal stability, and antimicrobial activity against these studied strains.
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Affiliation(s)
- Fatemeh Fayyaz
- Bioinorganic Chemistry Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, Iran
| | - Mehdi Rassa
- Department of Biology, Faculty of Science, University of Guilan, Rasht, Iran
| | - Rahmatollah Rahimi
- Bioinorganic Chemistry Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, Iran
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Amos-Tautua BM, Songca SP, Oluwafemi OS. Application of Porphyrins in Antibacterial Photodynamic Therapy. Molecules 2019; 24:E2456. [PMID: 31277423 PMCID: PMC6650910 DOI: 10.3390/molecules24132456] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 11/28/2022] Open
Abstract
Antibiotics are commonly used to control, treat, or prevent bacterial infections, however bacterial resistance to all known classes of traditional antibiotics has greatly increased in the past years especially in hospitals rendering certain therapies ineffective. To limit this emerging public health problem, there is a need to develop non-incursive, non-toxic, and new antimicrobial techniques that act more effectively and quicker than the current antibiotics. One of these effective techniques is antibacterial photodynamic therapy (aPDT). This review focuses on the application of porphyrins in the photo-inactivation of bacteria. Mechanisms of bacterial resistance and some of the current 'greener' methods of synthesis of meso-phenyl porphyrins are discussed. In addition, significance and limitations of aPDT are also discussed. Furthermore, we also elaborate on the current clinical applications and the future perspectives and directions of this non-antibiotic therapeutic strategy in combating infectious diseases.
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Affiliation(s)
- Bamidele M Amos-Tautua
- Department of Chemical Sciences, University of Johannesburg, Doornfontein Campus, P.O. Box 17011, Doornfontein 2028, South Africa
- Centre for Nanomaterials Science Research, University of Johannesburg, Johannesburg 2000, South Africa
| | - Sandile P Songca
- Department of Chemistry, University of KwaZulu-Natal, Private Bag X 54001, Durban 4000, South Africa
| | - Oluwatobi S Oluwafemi
- Department of Chemical Sciences, University of Johannesburg, Doornfontein Campus, P.O. Box 17011, Doornfontein 2028, South Africa.
- Centre for Nanomaterials Science Research, University of Johannesburg, Johannesburg 2000, South Africa.
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Issawi M, Guillaumot D, Sol V, Riou C. Responses of an adventitious fast-growing plant to photodynamic stress: comparative study of anionic and cationic porphyrin effect on Arabidopsis thaliana. PHYSIOLOGIA PLANTARUM 2018; 162:379-390. [PMID: 29111597 DOI: 10.1111/ppl.12666] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/26/2017] [Accepted: 10/29/2017] [Indexed: 06/07/2023]
Abstract
Antimicrobial photodynamic treatment (APDT) based on the use of a photosensitizer to produce reactive oxygen species (ROS) that induce cell death could be envisaged to fight against plant pathogens. For setting this strategy, we want to study how plants themselves respond to photodynamic treatment. In previous work we showed that tomato plantlets were able to resist photoactivated tetra (N-methylpyridyl) porphyrin (CP) or the zinc metalated form (CP-Zn). To enlarge our plant expertise related to exogenous porphyrins treatment and to further defend this approach, we studied how a weed like Arabidopsis thaliana responded to exogenous supply of anionic and cationic porphyrins. Both types of photosensitizers had no negative effect on seed germination and did not hamper the development etiolated Arabidopsis plantlet under dark conditions. Thus, post-emergence effects of porphyrin photoactivation on the development of 14 day-old in vitro Arabidopsis plantlet under light were observed. CP-Zn was the most efficient photosensitizer to kill Arabidopsis plantlets while anionic tetra (4-sulfonatophenyl) porphyrin only delayed their growth and development. Indeed only 7% of plantlets could be rescued after CP-Zn treatment. Furthermore, non-enzymatic and enzymatic defense components involved in detoxification of ROS generated by CP-Zn under illumination were downregulated or stable with the exception of sevenfold increase in proline content. As previously demonstrated in the literature for microbial agents and in the present work for Arabidopsis, CP-Zn was efficient enough to eradicate unwanted vegetation and plant pathogens without at the same time killing plants of agronomic interest such as tomato plantlets.
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Affiliation(s)
- Mohammad Issawi
- Laboratoire de Chimie des Substances Naturelles (EA 1069), Université de Limoges, Faculté des Sciences et Techniques, 87060 Limoges Cedex, France
| | - Damien Guillaumot
- Laboratoire de Chimie des Substances Naturelles (EA 1069), Université de Limoges, Faculté des Sciences et Techniques, 87060 Limoges Cedex, France
| | - Vincent Sol
- Laboratoire de Chimie des Substances Naturelles (EA 1069), Université de Limoges, Faculté des Sciences et Techniques, 87060 Limoges Cedex, France
| | - Catherine Riou
- Laboratoire de Chimie des Substances Naturelles (EA 1069), Université de Limoges, Faculté des Sciences et Techniques, 87060 Limoges Cedex, France
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O'Donoghue B, NicAogáin K, Bennett C, Conneely A, Tiensuu T, Johansson J, O'Byrne C. Blue-Light Inhibition of Listeria monocytogenes Growth Is Mediated by Reactive Oxygen Species and Is Influenced by σB and the Blue-Light Sensor Lmo0799. Appl Environ Microbiol 2016; 82:4017-4027. [PMID: 27129969 PMCID: PMC4907204 DOI: 10.1128/aem.00685-16] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/19/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Listeria monocytogenes senses blue light via the flavin mononucleotide-containing sensory protein Lmo0799, leading to activation of the general stress response sigma factor SigB (σ(B)). In this study, we investigated the physiological response of this foodborne pathogen to blue light. We show that blue light (460 to 470 nm) doses of 1.5 to 2 mW cm(-2) cause inhibition of growth on agar-based and liquid culture media. The inhibitory effects are dependent on cell density, with reduced effects evident when high cell numbers are present. The addition of 20 mM dimethylthiourea, a scavenger of reactive oxygen species, or catalase to the medium reverses the inhibitory effects of blue light, suggesting that growth inhibition is mediated by the formation of reactive oxygen species. A mutant strain lacking σ(B) (ΔsigB) was found to be less inhibited by blue light than the wild type, likely indicating the energetic cost of deploying the general stress response. When a lethal dose of light (8 mW cm(-2)) was applied to cells, the ΔsigB mutant displayed a marked increase in sensitivity to light compared to the wild type. To investigate the role of the blue-light sensor Lmo0799, mutants were constructed that either had a deletion of the gene (Δlmo0799) or alteration in a conserved cysteine residue at position 56, which is predicted to play a pivotal role in the photocycle of the protein (lmo0799 C56A). Both mutants displayed phenotypes similar to the ΔsigB mutant in the presence of blue light, providing genetic evidence that residue 56 is critical for light sensing in L. monocytogenes Taken together, these results demonstrate that L. monocytogenes is inhibited by blue light in a manner that depends on reactive oxygen species, and they demonstrate clear light-dependent phenotypes associated with σ(B) and the blue-light sensor Lmo0799. IMPORTANCE Listeria monocytogenes is a bacterial foodborne pathogen that can cause life-threatening infections in humans. It is known to be able to sense and respond to visible light. In this study, we examine the effects of blue light on the growth and survival of this pathogen. We show that growth can be inhibited at comparatively low doses of blue light, and that at higher doses, L. monocytogenes cells are killed. We present evidence suggesting that blue light inhibits this organism by causing the production of reactive oxygen species, such as hydrogen peroxide. We help clarify the mechanism of light sensing by constructing a "blind" version of the blue-light sensor protein. Finally, we show that activation of the general stress response by light has a negative effect on growth, probably because cellular resources are diverted into protective mechanisms rather than growth.
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Affiliation(s)
- Beth O'Donoghue
- Bacterial Stress Response Group, Microbiology, School of Natural Sciences, National University of Ireland, Galway, Galway, Ireland
| | - Kerrie NicAogáin
- Bacterial Stress Response Group, Microbiology, School of Natural Sciences, National University of Ireland, Galway, Galway, Ireland
| | - Claire Bennett
- National Centre for Laser Applications, School of Physics, National University of Ireland, Galway, Galway, Ireland
| | - Alan Conneely
- National Centre for Laser Applications, School of Physics, National University of Ireland, Galway, Galway, Ireland
| | - Teresa Tiensuu
- Department of Molecular Biology, Molecular Infection Medicine, Sweden, and Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Jörgen Johansson
- Department of Molecular Biology, Molecular Infection Medicine, Sweden, and Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Conor O'Byrne
- Bacterial Stress Response Group, Microbiology, School of Natural Sciences, National University of Ireland, Galway, Galway, Ireland
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Chang JE, Oak CH, Sung N, Jheon S. The potential application of photodynamic therapy in drug-resistant tuberculosis. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 150:60-5. [DOI: 10.1016/j.jphotobiol.2015.04.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 03/30/2015] [Accepted: 04/05/2015] [Indexed: 11/16/2022]
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Ghanbari H, Mousavi SA, Forouzanfar A, Zakeri M, Shafaee H, Shahnaseri S. Synergic phototoxic effect of visible light or Gallium-Arsenide laser in the presence of different photo-sensitizers on Porphyromonas gingivalis and Fusobacterium nucleatum. Dent Res J (Isfahan) 2015; 12:323-30. [PMID: 26288621 PMCID: PMC4533189 DOI: 10.4103/1735-3327.161432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background: According to the development of resistant strains of pathogenic bacteria following treatment with antimicrobial chemotherapeutic agents, alternative approaches such as lethal photosensitization are being used. The aim of this study was to evaluate the effect of visible light and laser beam radiation in conjugation with three different photosensitizers on the survival of two main periodontopathogenic bacteria including Porphyromonas gingivalis and Fusobacterium nucleatum in different exposure periods. Materials and Methods: In this in vitro prospective study, strains of P. gingivalis and F. nucleatum. were exposed to visible light at wavelengths of 440 nm and diode laser light, Gallium-Arsenide, at wavelength of 830 nm in the presence of a photosensitizer (erythrosine, curcuma, or hydrogen peroxide). They were exposed 1-5 min to each light. Each experiment was repeated 3 times for each strain of bacteria. Data were analyzed by two-ways ANOVA and least significant difference post-hoc tests. P < 0.05 was considered as significant. After 4 days the colonies were counted. Results: Viability of P. gingivalis was reduced 10% and 20% subsequent to exposure to visible light and diode laser, respectively. The values were 65% and 75% for F. nucleatum in a period of 5-min, respectively. Exposure to visible light or laser beam in conjugation with the photosensitizers suspension caused significant reduction in the number of P. gingivalis in duration of 5-min, suggesting a synergic phototoxic effect. However, the survival rate of F. nucleatum following the exposure to laser with hydrogen peroxide, erythrosine and rhizome of Curcuma longa (curcumin) after 5-min was 10%, 20% and 90% respectively. Conclusion: Within the limitations of this study, the synergic phototoxic effect of visible light in combination with each of the photosensitizers on P. gingivalis and F. nucleatum. However, the synergic phototoxic effect of laser exposure and hydrogen peroxide and curcumin as photosensitizers on F. nucleatum was not shown.
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Affiliation(s)
- Habibollah Ghanbari
- Oral and Maxillofacial Diseases Research Center and Department of Periodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Seyed Amir Mousavi
- Torabinejad Dental Research Center and Departments of Endodontics, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ali Forouzanfar
- Oral and Maxillofacial Diseases Research Center and Department of Periodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahdi Zakeri
- Oral and Maxillofacial Diseases Research Center and Department of Periodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hooman Shafaee
- Dental Research Center, Department of Orthodontics, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Shirin Shahnaseri
- Dental Implant Research Center and Oral and Maxillofacial Surgery, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
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Abstract
The emergence of microbial resistance is becoming a global problem in clinical and environmental areas. As such, the development of drugs with novel modes of action will be vital to meet the threats created by the rise in microbial resistance. Microbial photodynamic inactivation is receiving considerable attention for its potentialities as a new antimicrobial treatment. This review addresses the interactions between photosensitizers and bacterial cells (binding site and cellular localization), the ultrastructural, morphological and functional changes observed at initial stages and during the course of photodynamic inactivation, the oxidative alterations in specific molecular targets, and a possible development of resistance.
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Alves E, Faustino MA, Tomé JP, Neves MG, Tomé AC, Cavaleiro JA, Cunha Â, Gomes NC, Almeida A. Nucleic acid changes during photodynamic inactivation of bacteria by cationic porphyrins. Bioorg Med Chem 2013; 21:4311-8. [DOI: 10.1016/j.bmc.2013.04.065] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 04/22/2013] [Accepted: 04/24/2013] [Indexed: 10/26/2022]
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13
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Gong AS, Lanzl CA, Cwiertny DM, Walker SL. Lack of influence of extracellular polymeric substances (EPS) level on hydroxyl radical mediated disinfection of Escherichia coli. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:241-249. [PMID: 22082030 DOI: 10.1021/es202541r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Photolysis of nitrate, a prevalent constituent in agriculturally impacted waters, may influence pathogen attenuation in such systems through production of hydroxyl radical ((•)OH). This study focuses on the efficacy of (•)OH generated during nitrate photolysis in promoting E. coli die-off as a function of extracellular polymeric substances (EPS) coverage. EPS levels of four E. coli isolates were systematically altered through a sonication extraction method and photochemical batch experiments with a solar simulator examined isolate viability loss as a function of time in nitrate solutions. E. coli viability loss over time exhibited two regimes: an initial induction time, t(s), with little decay was followed by rapid exponential decay characterized by a first-order disinfection rate constant, k. Increasing steady-state (•)OH concentrations enhanced E. coli viability loss, increasing values of k and decreasing t(s) values, both of which were quantified with a multitarget bacterial disinfection model. Notably, at a given steady-state (•)OH concentration, values of t(s) and k were independent of EPS levels, nor did they vary among the different E. coli strains considered. Results herein show that while (•)OH generated via nitrate photolysis enhances rates of disinfection in surface water, the mechanism by which (•)OH kills E. coli is relatively insensitive to common bacterial variables.
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Affiliation(s)
- Amy S Gong
- Department of Chemical & Environmental Engineering, University of California, Riverside, California 92521, United States
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14
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Tavares A, Dias SRS, Carvalho CMB, Faustino MAF, Tomé JPC, Neves MGPMS, Tomé AC, Cavaleiro JAS, Cunha Â, Gomes NCM, Alves E, Almeida A. Mechanisms of photodynamic inactivation of a gram-negative recombinant bioluminescent bacterium by cationic porphyrins. Photochem Photobiol Sci 2011; 10:1659-69. [PMID: 21799996 DOI: 10.1039/c1pp05097d] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photodynamic therapy is a very promising approach to inactivate pathogenic microorganisms. The photodamage of cells involves reactive oxygen species (ROS) which are generated in situ by two main mechanisms (type I and/or type II). The mechanism responsible for the photoinactivation (PI) of a bioluminescent recombinant Escherichia coli, induced by three different cationic porphyrins, was identified in this work using a rapid method based on the monitoring of the metabolic activity of this bacterium. The inhibitory effect of the photodynamic process in the presence of a singlet oxygen quencher (sodium azide) or free radical scavengers (d-mannitol and l-cysteine) was evaluated by exposing bacterial suspensions with 0.5 μM Tri-Py(+)-Me-PF, 5.0 μM Tetra-Py(+)-Me or 5.0 μM Tri-SPy(+)-Me-PF to white light. Strong bacterial protection was observed with sodium azide (100 mM) for the three cationic porphyrins. However, in the presence of Tri-Py(+)-Me-PF and Tetra-Py(+)-Me and the free radical scavengers (l-cysteine and d-mannitol) the reduction on the bacterial bioluminescence was significantly higher and similar to that obtained in their absence (5.4-6.0 log reduction). In the case of Tri-SPy(+)-Me-PF two distinct behaviours were observed when l-cysteine and d-mannitol were used as free radical scavengers: while the presence of l-cysteine (100 mM) lead to a bacterial protection similar to the one observed with sodium azide, in the presence of d-mannitol only a small protection was detected. The high inhibition of the PS activity by l-cysteine is not due to its radical scavenger ability but due to the singlet oxygen quenching by the sulfanyl group (-SH). In fact, the photodecomposition of 1,3-diphenylisobenzofuran in the presence of Tri-SPy(+)-Me-PF is completely suppressed when l-cysteine is present. The results obtained in this study suggest that singlet oxygen (type II mechanism) plays a very important role over free radicals (type I mechanism) on the PI process of the bioluminescent E. coli by Tri-Py(+)-Me-PF, Tetra-Py(+)-Me and Tri-SPy(+)-Me-PF. Although the use of scavengers is an adequate and simple approach to evaluate the relative importance of the two pathways, it is important to choose scavengers which do not interfere in both PI mechanisms. Sodium azide and d-mannitol seem to be good oxygen and free radical quenchers, respectively, to study the PI mechanisms by porphyrinic photosensitizers.
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Affiliation(s)
- Anabela Tavares
- CESAM and Department of Biology, University of Aveiro, 3810-193, Aveiro, Portugal
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Harris F, Pierpoint L. Photodynamic therapy based on 5-aminolevulinic acid and its use as an antimicrobial agent. Med Res Rev 2011; 32:1292-327. [PMID: 21793017 DOI: 10.1002/med.20251] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Exogenous 5-aminolevulinic acid (ALA) is taken up directly by bacteria, yeasts, fungi, and some parasites, which then induces the accumulation of protoporphyrin IX (PPIX). Subsequent light irradiation of PPIX leads to the inactivation of these organisms via photodamage to their cellular structures. ALA uptake and light irradiation of PPIX produced by host cells leads to the inactivation of other parasites, along with some viruses, via the induction of an immune response. ALA-mediated PPIX production by host cells and light irradiation result in the inactivation of other viruses via either the induction of a host cell response or direct photodynamic attack on viral particles. This ALA-mediated production of light-activated PPIX has been extensively used as a form of photodynamic therapy (PDT) and has shown varying levels of efficacy in treating conditions that are associated with microbial infection, ranging from acne and verrucae to leishmaniasis and onychomycosis. However, for the treatment of some of these conditions by ALA-based PDT, the role of an antimicrobial effect has been disputed and in general, the mechanisms by which the technique inactivates microbes are not well understood. In this study, we review current understanding of the antimicrobial mechanisms used by ALA-based PDT and its role in the treatment of microbial infections along with its potential medical and nonmedical applications.
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Affiliation(s)
- Frederick Harris
- School of Forensic and Investigative Sciences, University of Central Lancashire, Preston, Lancashire, United Kingdom. fharris1@.ac.uk
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Photodynamic antimicrobial chemotherapy in aquaculture: photoinactivation studies of Vibrio fischeri. PLoS One 2011; 6:e20970. [PMID: 21698119 PMCID: PMC3117864 DOI: 10.1371/journal.pone.0020970] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Accepted: 05/15/2011] [Indexed: 11/19/2022] Open
Abstract
Background Photodynamic antimicrobial chemotherapy (PACT) combines light, a light-absorbing molecule that initiates a photochemical or photophysical reaction, and oxygen. The combined action of these three components originates reactive oxygen species that lead to microorganisms' destruction. The aim was to evaluate the efficiency of PACT on Vibrio fischeri: 1) with buffer solution, varying temperature, pH, salinity and oxygen concentration values; 2) with aquaculture water, to reproduce photoinactivation (PI) conditions in situ. Methodology/Principal Findings To monitor the PI kinetics, the bioluminescence of V. fischeri was measured during the experiments. A tricationic meso-substituted porphyrin (Tri-Py+-Me-PF) was used as photosensitizer (5 µM in the studies with buffer solution and 10–50 µM in the studies with aquaculture water); artificial white light (4 mW cm−2) and solar irradiation (40 mW cm−2) were used as light sources; and the bacterial concentration used for all experiments was ≈107 CFU mL−1 (corresponding to a bioluminescence level of 105 relative light units - RLU). The variations in pH (6.5–8.5), temperature (10–25°C), salinity (20–40 g L−1) and oxygen concentration did not significantly affect the PI of V. fischeri, once in all tested conditions the bioluminescent signal decreased to the detection limit of the method (≈7 log reduction). The assays using aquaculture water showed that the efficiency of the process is affected by the suspended matter. Total PI of V. fischeri in aquaculture water was achieved under solar light in the presence of 20 µM of Tri-Py+-Me-PF. Conclusions/Significance If PACT is to be used in environmental applications, the matrix containing target microbial communities should be previously characterized in order to establish an efficient protocol having into account the photosensitizer concentration, the light source and the total light dose delivered. The possibility of using solar light in PACT to treat aquaculture water makes this technology cost-effective and attractive.
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Costa L, Carvalho CMB, Faustino MAF, Neves MGPMS, Tomé JPC, Tomé AC, Cavaleiro JAS, Cunha A, Almeida A. Sewage bacteriophage inactivation by cationic porphyrins: influence of light parameters. Photochem Photobiol Sci 2010; 9:1126-33. [PMID: 20563346 DOI: 10.1039/c0pp00051e] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photodynamic therapy has been used to inactivate microorganisms through the use of targeted photosensitizers. Although the photoinactivation of microorganisms has already been studied under different conditions, a systematic evaluation of irradiation characteristics is still limited. The goal of this study was to test how the light dose, fluence rate and irradiation source affect the viral photoinactivation of a T4-like sewage bacteriophage. The experiments were carried out using white PAR light delivered by fluorescent PAR lamps (40 W m(-2)), sun light (600 W m(-2)) and an halogen lamp (40-1690 W m(-2)). Phage suspensions and two cationic photosensitizers (Tetra-Py(+)-Me, Tri-Py(+)-Me-PF) at concentrations of 0.5, 1.0 and 5.0 microM were used. The results showed that the efficacy of the bacteriophage photoinactivation is correlated not only with the sensitizer and its concentration but also with the light source, energy dose and fluence rate applied. Both photosensitizers at 5.0 microM were able to inactivate the T4-like phage to the limit of detection for each light source and fluence rate. However, depending of the light parameters, different irradiation times are required. The efficiency of photoinactivation is dependent on the spectral emission distribution of the light sources used. Considering the same light source and a fixed light dose applied at different fluence rates, phage inactivation was significantly higher when low fluence rates were used. In this way, the light source, fluence rate and total light dose play an important role in the effectiveness of the antimicrobial photodynamic therapy and should always be considered when establishing an optimal antimicrobial protocol.
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Affiliation(s)
- Liliana Costa
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
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Ä°dil Ã, Ãzkanca R, Darcan C, Flint KP. Escherichia coli:Dominance of Red Light over Other Visible Light Sources in Establishing Viable but Nonculturable State. Photochem Photobiol 2010; 86:104-9. [DOI: 10.1111/j.1751-1097.2009.00636.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Almeida A, Cunha Â, Gomes NC, Alves E, Costa L, Faustino MA. Phage therapy and photodynamic therapy: low environmental impact approaches to inactivate microorganisms in fish farming plants. Mar Drugs 2009; 7:268-313. [PMID: 19841715 PMCID: PMC2763101 DOI: 10.3390/md7030268] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2009] [Revised: 06/22/2009] [Accepted: 06/25/2009] [Indexed: 12/11/2022] Open
Abstract
Owing to the increasing importance of aquaculture to compensate for the progressive worldwide reduction of natural fish and to the fact that several fish farming plants often suffer from heavy financial losses due to the development of infections caused by microbial pathogens, including multidrug resistant bacteria, more environmentally-friendly strategies to control fish infections are urgently needed to make the aquaculture industry more sustainable. The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy.
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Affiliation(s)
- Adelaide Almeida
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro – Portugal; E-Mails: (A.C.); (N.C.M.G.); (E.A.); (L.C.)
| | - Ângela Cunha
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro – Portugal; E-Mails: (A.C.); (N.C.M.G.); (E.A.); (L.C.)
| | - Newton C.M. Gomes
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro – Portugal; E-Mails: (A.C.); (N.C.M.G.); (E.A.); (L.C.)
| | - Eliana Alves
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro – Portugal; E-Mails: (A.C.); (N.C.M.G.); (E.A.); (L.C.)
| | - Liliana Costa
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro – Portugal; E-Mails: (A.C.); (N.C.M.G.); (E.A.); (L.C.)
| | - Maria A.F. Faustino
- QOPNA and Department of Chemistry, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro – Portugal; E-Mail:
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Krouit M, Granet R, Krausz P. Photobactericidal films from porphyrins grafted to alkylated cellulose – synthesis and bactericidal properties. Eur Polym J 2009. [DOI: 10.1016/j.eurpolymj.2008.11.036] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ghaderi M, Bathaie SZ, Saboury AA, Sharghi H, Tangestaninejad S. Interaction of an Fe derivative of TMAP (Fe(TMAP)OAc) with DNA in comparison with free-base TMAP. Int J Biol Macromol 2007; 41:173-9. [PMID: 17343908 DOI: 10.1016/j.ijbiomac.2007.01.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2006] [Revised: 01/27/2007] [Accepted: 01/27/2007] [Indexed: 11/17/2022]
Abstract
We investigated the interaction of meso-tetrakis (N-para-methylanilium) porphyrin (TMAP) in its free base and Fe(II) form (Fe(TMAP)OAc) as a new derivative, with high molecular weight DNA at different ionic strengths, using various spectroscopic methods and microcalorimetry. The data obtained by spectrophotometery, circular dichroism (CD), fluorescence quenching and resonance light scattering (RLS) have demonstrated that TMAP association with DNA is via outside binding with self-stacking manner, which is accompanied with the "end-on" type complex formation in low ionic strength. However, in the case of Fe(TMAP)OAc, predominant mode of interaction is groove binding and after increasing in DNA concentration, unstable stacking-type aggregates are formed. In addition, isothermal titration calorimetric measurements have indicated the exothermic process of porphyrins binding to DNA, but the exothermisity in metal derivative of porphyrin is less than the free base. It confirmed the formation of a more organized aggregate of TMAP on DNA surface. Interactions of both porphyrins with DNA show high sensitivity to ionic strength. By addition of salt, the downfield CD signal of TMAP aggregates is shifted to a higher wavelength, which indicates some changes in the aggregates position. In the case of Fe(TMAP)OAc, addition of salt leads to changes in the mode of binding from groove binding to outside binding with self-stacking, which is accompanied with major changes in CD spectra, possibly indicating the formation of "face-on" type complex.
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Affiliation(s)
- Masoumeh Ghaderi
- Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University (TMU), PO Box 14115-111, Tehran, Iran
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Cavaleiro JAS, Tomé JPC, Faustino MAF. Synthesis of Glycoporphyrins. HETEROCYCLES FROM CARBOHYDRATE PRECURSORS 2007. [DOI: 10.1007/7081_2007_056] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Egyeki M, Tóth K, Waldeck W, Schmezer P, Langowski J, Csík G. DNA damaging capability of hematoporphyrin towards DNAs of various accessibilities. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2006; 84:119-27. [PMID: 16549364 DOI: 10.1016/j.jphotobiol.2006.02.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2005] [Revised: 01/17/2006] [Accepted: 02/06/2006] [Indexed: 11/16/2022]
Abstract
In this work we wanted to verify that photoactivation of DNA-non-binding porphyrin derivative hematoporphyrin IX (Hp) is able to induce damages in DNAs of various accessibilities such as B-conformation and superhelical isolated DNA, nucleoprotein complex and intracellular DNAs. It was found that photodynamic reaction of Hp results significant changes in thermal stability of isolated T7 DNA and induces single strand breaks in supercoiled Bluescript plasmid isolated from Escherichia coli cells. As optical melting measurements revealed, the irradiation of photosensitized T7 nucleoprotein complex leads to a destabilization of the protein capsid. The photodynamic reaction affected both the protein structure and DNA-protein interaction, however, the parameters corresponding to the DNA denaturation are not influenced. The accumulation of Hp in HeLa cells was followed by laser scanning confocal microscopy. The picture received is typical for lipophilic dyes. When Hp loaded cells were irradiated, a reduction of viability could be observed in a concentration and a light dose dependent manner; 12microM porphyrin induced almost complete cell killing after 30min irradiation. After similar treatment, alkaline agarose gel electrophoresis of isolated nuclear DNA did not show the presence of single strand breaks. The alkaline comet assay also failed to demonstrate any DNA damage in HeLa cells. We also considered the possibility of the generation of damages in intracellular SV40 DNA. According to the electropherograms there was no difference between the patterns of DNAs from treated and control samples.
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Affiliation(s)
- M Egyeki
- Institute of Biophysics and Radiation Biology, Semmelweis University, Hungarian Academy of Science, P.O. Box 263, H-1444 Budapest, Hungary
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Krouit M, Granet R, Branland P, Verneuil B, Krausz P. New photoantimicrobial films composed of porphyrinated lipophilic cellulose esters. Bioorg Med Chem Lett 2006; 16:1651-5. [PMID: 16377183 DOI: 10.1016/j.bmcl.2005.12.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Revised: 12/06/2005] [Accepted: 12/06/2005] [Indexed: 11/16/2022]
Abstract
Porphyrinated cellulose laurate esters have been prepared in homogeneous DMA/LiCl medium by "one-pot, two-step" reactions starting from cellulose, protoporphyrin IX, and lauric acid and using a TsCl/Pyridine system. The plastic films obtained after casting were shown to display photobactericidal activity against Gram positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. This new photobactericidal polymer has potential for industrial, medical, or household applications.
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Affiliation(s)
- Mohammed Krouit
- Université de Limoges, Laboratoire de Chimie des Substances Naturelles, 123 Avenue Albert Thomas, 87060 Limoges cedex, France
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Sol V, Branland P, Chaleix V, Granet R, Guilloton M, Lamarche F, Verneuil B, Krausz P. Amino porphyrins as photoinhibitors of Gram-positive and -negative bacteria. Bioorg Med Chem Lett 2005; 14:4207-11. [PMID: 15261271 DOI: 10.1016/j.bmcl.2004.06.016] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2004] [Revised: 05/31/2004] [Accepted: 06/08/2004] [Indexed: 11/20/2022]
Abstract
Twenty four aminoporphyrin derivatives have been tested in vitro for their antibacterial photoactivity against Escherichia coli and Staphylococcus aureus. Two of these compounds, bearing polyamine units, exhibited a significant activity especially against Gram-negative bacteria (E. coli).
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Affiliation(s)
- V Sol
- Université de Limoges, Laboratoire de Chimie des Substances Naturelles, 123, Avenue Albert Thomas, 87060 Limoges, France.
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Hamblin MR, Hasan T. Photodynamic therapy: a new antimicrobial approach to infectious disease? Photochem Photobiol Sci 2004; 3:436-50. [PMID: 15122361 PMCID: PMC3071049 DOI: 10.1039/b311900a] [Citation(s) in RCA: 1314] [Impact Index Per Article: 65.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Photodynamic therapy (PDT) employs a non-toxic dye, termed a photosensitizer (PS), and low intensity visible light which, in the presence of oxygen, combine to produce cytotoxic species. PDT has the advantage of dual selectivity, in that the PS can be targeted to its destination cell or tissue and, in addition, the illumination can be spatially directed to the lesion. PDT has previously been used to kill pathogenic microorganisms in vitro, but its use to treat infections in animal models or patients has not, as yet, been much developed. It is known that Gram-(-) bacteria are resistant to PDT with many commonly used PS that will readily lead to phototoxicity in Gram-(+) species, and that PS bearing a cationic charge or the use of agents that increase the permeability of the outer membrane will increase the efficacy of killing Gram-(-) organisms. All the available evidence suggests that multi-antibiotic resistant strains are as easily killed by PDT as naive strains, and that bacteria will not readily develop resistance to PDT. Treatment of localized infections with PDT requires selectivity of the PS for microbes over host cells, delivery of the PS into the infected area and the ability to effectively illuminate the lesion. Recently, there have been reports of PDT used to treat infections in selected animal models and some clinical trials: mainly for viral lesions, but also for acne, gastric infection by Helicobacter pylori and brain abcesses. Possible future clinical applications include infections in wounds and burns, rapidly spreading and intractable soft-tissue infections and abscesses, infections in body cavities such as the mouth, ear, nasal sinus, bladder and stomach, and surface infections of the cornea and skin.
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Affiliation(s)
- Michael R Hamblin
- Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA.
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