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Stewart CF, McGoldrick P, Anderson JG, MacGregor SJ, Atreya CD, Maclean M. Microbial reduction of prebagged human plasma using 405 nm light and its effects on coagulation factors. AMB Express 2024; 14:66. [PMID: 38842656 PMCID: PMC11156813 DOI: 10.1186/s13568-024-01725-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 05/27/2024] [Indexed: 06/07/2024] Open
Abstract
Bacterial contamination is the most prevalent infectious complication of blood transfusion in the developed world. To mitigate this, several ultraviolet light-based pathogen reduction technologies (PRTs), some of which require photo-chemicals, have been developed to minimize infection transmission. Relative to UV light, visible 405-nm light is safer and has shown potential to be developed as a PRT for the in situ treatment of ex vivo human plasma and platelet concentrates, without the need for photo-chemicals. This study investigates the effect of 405-nm light on human plasma, with focus on the compatibility of antimicrobial light doses with essential plasma clotting factors. To determine an effective antimicrobial dose that is compatible with plasma, prebagged human plasma (up to 300 mL) was seeded with common microbial contaminants and treated with increasing doses of 405-nm light (16 mW cm-2; ≤ 403 J cm-2). Post-exposure plasma protein integrity was investigated using an AOPP assay, in vitro coagulation tests, and ELISA-based measurement of fibrinogen and Protein S. Microbial contamination in 300 mL prebagged human plasma was significantly reduced (P ≤ 0.05) after exposure to ≤ 288 J cm-2, with microbial loads reduced by > 96.2%. This dose did not significantly affect the plasma protein quality parameters tested (P > 0.05). Increased doses (≥ 345 J cm-2) resulted in a 4.3% increase in clot times with no statistically significant change in protein activity or levels. Overall, this study has demonstrated that the effective microbicidal 405 light dose shows little to no negative effect on plasma quality.
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Affiliation(s)
- Caitlin F Stewart
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Royal College Building, 204 George Street, Glasgow, UK
| | - Preston McGoldrick
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - John G Anderson
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Royal College Building, 204 George Street, Glasgow, UK
| | - Scott J MacGregor
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Royal College Building, 204 George Street, Glasgow, UK
| | - Chintamani D Atreya
- Office of Blood Research and Review, Center for Biologics Evaluation and Research (CBER), Food and Drug Administration, Silver Spring, MD, USA
| | - Michelle Maclean
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Royal College Building, 204 George Street, Glasgow, UK.
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK.
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El-Gendy AO, Ezzat S, Samad FA, Dabbous OA, Dahm J, Hamblin MR, Mohamed T. Studying the viability and growth kinetics of vancomycin-resistant Enterococcus faecalis V583 following femtosecond laser irradiation (420-465 nm). Lasers Med Sci 2024; 39:144. [PMID: 38809462 PMCID: PMC11136855 DOI: 10.1007/s10103-024-04080-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 05/12/2024] [Indexed: 05/30/2024]
Abstract
Enterococcus faecalis is among the most resistant bacteria found in infected root canals. The demand for cutting-edge disinfection methods has rekindled research on photoinactivation with visible light. This study investigated the bactericidal activity of femtosecond laser irradiation against vancomycin-resistant Enterococcus faecalis V583 (VRE). The effect of parameters such as wavelength and energy density on the viability and growth kinetics of VRE was studied to design an optimized laser-based antimicrobial photoinactivation approach without any prior addition of exogenous photosensitizers. The most effective wavelengths were 430 nm and 435 nm at a fluence of 1000 J/cm2, causing a nearly 2-log reduction (98.6% and 98.3% inhibition, respectively) in viable bacterial counts. The colony-forming units and growth rate of the laser-treated cultures were progressively decreased as energy density or light dose increased at 445 nm but reached a limit at 1250 J/cm2. At a higher fluence of 2000 J/cm2, the efficacy was reduced due to a photobleaching phenomenon. Our results highlight the importance of optimizing laser exposure parameters, such as wavelength and fluence, in bacterial photoinactivation experiments. To our knowledge, this is the first study to report an optimized wavelength for the inactivation of VRE using visible femtosecond laser light.
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Affiliation(s)
- Ahmed O El-Gendy
- Laser Institute for Research and Applications LIRA, Beni-Suef University, Beni-Suef, 62511, Egypt
- Department of Microbiology and Immunology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt
| | - Sarah Ezzat
- Department of Microbiology and Immunology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt
| | - Fatma Abdel Samad
- Department of Microbiology and Immunology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt
| | - Ola Ali Dabbous
- Department of Medical Applications of Lasers, National Institute of Laser Enhanced Science (NILES), Cairo University, Giza, 12611, Egypt
| | | | - Michael R Hamblin
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein, 2028, South Africa
| | - Tarek Mohamed
- Laser Institute for Research and Applications LIRA, Beni-Suef University, Beni-Suef, 62511, Egypt.
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Sinclair LG, Anderson JG, MacGregor SJ, Maclean M. Enhanced antimicrobial efficacy and energy efficiency of low irradiance 405-nm light for bacterial decontamination. Arch Microbiol 2024; 206:276. [PMID: 38777923 PMCID: PMC11111507 DOI: 10.1007/s00203-024-03999-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 04/28/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024]
Abstract
Due to its increased safety over ultraviolet light, there is interest in the development of antimicrobial violet-blue light technologies for infection control applications. To ensure compatibility with exposed materials and tissue, the light irradiances and dose regimes used must be suitable for the target application. This study investigates the antimicrobial dose responses and germicidal efficiency of 405 nm violet-blue light when applied at a range of irradiance levels, for inactivation of surface-seeded and suspended bacteria. Bacteria were seeded onto agar surfaces (101-108 CFUplate-1) or suspended in PBS (103-109 CFUmL-1) and exposed to increasing doses of 405-nm light (≤ 288 Jcm-2) using various irradiances (0.5-150 mWcm-2), with susceptibility at equivalent light doses compared. Bacterial reductions ≥ 96% were demonstrated in all cases for lower irradiance (≤ 5 mWcm-2) exposures. Comparisons indicated, on a per unit dose basis, that significantly lower doses were required for significant reductions of all species when exposed at lower irradiances: 3-30 Jcm-2/0.5 mWcm-2 compared to 9-75 Jcm-2/50 mWcm-2 for low cell density (102 CFUplate-1) surface exposures and 22.5 Jcm-2/5 mWcm-2 compared to 67.5 Jcm-2/150 mWcm-2 for low density (103 CFUmL-1) liquid exposures (P ≤ 0.05). Similar patterns were observed at higher densities, excluding S. aureus exposed at 109 CFUmL-1, suggesting bacterial density at predictable levels has minimal influence on decontamination efficacy. This study provides fundamental evidence of the greater energy efficacy of 405-nm light for inactivation of clinically-significant pathogens when lower irradiances are employed, further supporting its relevance for practical decontamination applications.
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Affiliation(s)
- Lucy G Sinclair
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - John G Anderson
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Scott J MacGregor
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Michelle Maclean
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK.
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK.
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Olszewska MA, Dev Kumar G, Hur M, Diez-Gonzalez F. Inactivation of dried cells and biofilms of Listeria monocytogenes by exposure to blue light at different wavelengths and the influence of surface materials. Appl Environ Microbiol 2023; 89:e0114723. [PMID: 37846990 PMCID: PMC10617584 DOI: 10.1128/aem.01147-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 08/31/2023] [Indexed: 10/18/2023] Open
Abstract
Antimicrobial blue light (aBL) in the 400-470 nm wavelength range has been reported to kill multiple bacteria. This study assessed its potential for mitigating an important foodborne pathogen, Listeria monocytogenes (Lm), focusing on surface decontamination. Three wavelengths were tested, with gallic acid as a photosensitizing agent (Ps), against dried cells obtained from bacterial suspensions, and biofilms on stainless-steel (SS) coupons. Following aBL exposure, standard microbiological analysis of inoculated coupons was conducted to measure viability. Statistical analysis of variance was performed. Confocal laser scanning microscopy was used to observe the biofilm structures. Within 16 h of exposure at 405 nm, viable Lm dried cells and biofilms were reduced by approx. 3 log CFU/cm2 with doses of 2,672 J/cm2. Application of Ps resulted in an additional 1 log CFU/cm2 at 668 J/cm2, but its effect was not consistent. The highest dose (960 J/cm2) at 420 nm reduced viable counts on the biofilms by 1.9 log CFU/cm2. At 460 nm, after 800 J/cm2, biofilm counts were reduced by 1.6 log CFU/cm2. The effect of material composition on Lm viability was also investigated. Irradiation at 405 nm (668 J/cm2) of cells dried on polystyrene resulted in one of the largest viability reductions (4.0 log CFU/cm2), followed by high-density polyethylene (3.5 log CFU/cm2). Increasing the dose to 4,008 J/cm2 from 405 nm (24 h), improved its efficacy only on SS and polyvinyl chloride. Biofilm micrographs displayed a decrease in biofilm biomass due to the removal of biofilm portions from the surface and a shift from live to dead cells suggesting damage to biofilm cell membranes. These results suggest that aBL is a potential intervention to treat Lm contamination on typical material surfaces used in food production.IMPORTANCECurrent cleaning and sanitation programs are often not capable of controlling pathogen biofilms on equipment surfaces, which transmit the bacteria to ready-to-eat foods. The presence of native plant microbiota and organic matter can protect pathogenic bacteria by reducing the efficacy of sanitizers as well as promoting biofilm formation. Post-operation washing and sanitizing of produce contact surfaces might not be adequate in eliminating the presence of pathogens and commensal bacteria. The use of a dynamic and harmless light technology during downtime and close of operation could serve as a useful tool in preventing biofilm formation and persistence. Antimicrobial blue light (aBL) technology has been explored for hospital disinfection with very promising results, but its application to control foodborne pathogens remains relatively limited. The use of aBL could be a complementary strategy to inactivate surfaces in restaurant or supermarket deli settings.
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Affiliation(s)
- Magdalena A. Olszewska
- Center for Food Safety, University of Georgia, Griffin, Georgia, USA
- Department of Industrial and Food Microbiology, The Faculty of Food Science, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland
| | | | - Minji Hur
- Center for Food Safety, University of Georgia, Griffin, Georgia, USA
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Chen H, Cheng Y, Moraru CI. Blue 405 nm LED light effectively inactivates bacterial pathogens on substrates and packaging materials used in food processing. Sci Rep 2023; 13:15472. [PMID: 37726297 PMCID: PMC10509141 DOI: 10.1038/s41598-023-42347-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 09/08/2023] [Indexed: 09/21/2023] Open
Abstract
This study investigates the antimicrobial effectiveness of 405 nm light emitting diodes (LEDs) against pathogenic Escherichia coli O157:H7, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella Typhimurium, and Staphylococcus aureus, in thin liquid films (TLF) and on solid surfaces. Stainless steel (SS), high density polyethylene (HDPE), low density polyethylene (LDPE), and borosilicate glass were used as materials typically encountered in food processing, food service, and clinical environments. Anodic aluminum oxide (AAO) coupons with nanoscale topography were used, to evaluate the effect of topography on inactivation. The impact of surface roughness, hydrophobicity, and reflectivity on inactivation was assessed. A 48 h exposure to 405 nm led to reductions ranging from 1.3 (E. coli) to 5.7 (S. aureus) log CFU in TLF and 3.1 to 6.3 log CFU on different solid contact surfaces and packaging materials. All inactivation curves were nonlinear and followed Weibull kinetics, with better inactivation predictions on surfaces (0.89 ≤ R2 ≤ 1.0) compared to TLF (0.76 ≤ R2 ≤ 0.99). The fastest inactivation rate was observed on small nanopore AAO coupons inoculated with L. monocytogenes and S. aureus, indicating inactivation enhancing potential of these surfaces. These results demonstrate significant promise of 405 nm LEDs for antimicrobial applications in food processing and handling and the healthcare industry.
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Affiliation(s)
- Hanyu Chen
- Department of Food Science, Cornell University, Ithaca, NY, 14853, USA
| | - Yifan Cheng
- Department of Food Science, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Carmen I Moraru
- Department of Food Science, Cornell University, Ithaca, NY, 14853, USA.
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Chen L, Zhao Y, Wu W, Zeng Q, Wang JJ. New trends in the development of photodynamic inactivation against planktonic microorganisms and their biofilms in food system. Compr Rev Food Sci Food Saf 2023; 22:3814-3846. [PMID: 37530552 DOI: 10.1111/1541-4337.13215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 07/06/2023] [Accepted: 07/10/2023] [Indexed: 08/03/2023]
Abstract
The photodynamic inactivation (PDI) is a novel and effective nonthermal inactivation technology. This review provides a comprehensive overview on the bactericidal ability of endogenous photosensitizers (PSs)-mediated and exogenous PSs-mediated PDI against planktonic bacteria and their biofilms, as well as fungi. In general, the PDI exhibited a broad-spectrum ability in inactivating planktonic bacteria and fungi, but its potency was usually weakened in vivo and for eradicating biofilms. On this basis, new strategies have been proposed to strengthen the PDI potency in food system, mainly including the physical and chemical modification of PSs, the combination of PDI with multiple adjuvants, adjusting the working conditions of PDI, improving the targeting ability of PSs, and the emerging aggregation-induced emission luminogens (AIEgens). Meanwhile, the mechanisms of PDI on eradicating mono-/mixed-species biofilms and preserving foods were also summarized. Notably, the PDI-mediated antimicrobial packaging film was proposed and introduced. This review gives a new insight to develop the potent PDI system to combat microbial contamination and hazard in food industry.
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Affiliation(s)
- Lu Chen
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| | - Yong Zhao
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
- Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs, Shanghai, China
| | - Weiliang Wu
- Food Safety and Health Research Center, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Qiaohui Zeng
- Guangdong Provincial Key Laboratory of Intelligent Food Manufacturing, Foshan University, Foshan, China
- Foshan Research Center for Quality Safety of the Whole Industry Chain of Agricultural Products, Foshan University, Foshan, China
| | - Jing Jing Wang
- College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
- Guangdong Provincial Key Laboratory of Intelligent Food Manufacturing, Foshan University, Foshan, China
- National Technical Center (Foshan) for Quality Control of Famous and Special Agricultural Products, Foshan University, Foshan, China
- Foshan Research Center for Quality Safety of the Whole Industry Chain of Agricultural Products, Foshan University, Foshan, China
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7
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Sinclair LG, Dougall LR, Ilieva Z, McKenzie K, Anderson JG, MacGregor SJ, Maclean M. Laboratory evaluation of the broad-spectrum antibacterial efficacy of a low-irradiance visible 405-nm light system for surface-simulated decontamination. HEALTH AND TECHNOLOGY 2023; 13:1-15. [PMID: 37363345 PMCID: PMC10264887 DOI: 10.1007/s12553-023-00761-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 05/30/2023] [Indexed: 06/28/2023]
Abstract
Purpose Lighting systems which use visible light blended with antimicrobial 405-nm violet-blue light have recently been developed for safe continuous decontamination of occupied healthcare environments. This paper characterises the optical output and antibacterial efficacy of a low irradiance 405-nm light system designed for environmental decontamination applications, under controlled laboratory conditions. Methods In the current study, the irradiance output of a ceiling-mounted 405-nm light source was profiled within a 3×3×2 m (18 m3) test area; with values ranging from 0.001-2.016 mWcm-2. To evaluate antibacterial efficacy of the light source for environmental surface decontamination, irradiance levels within this range (0.021-1 mWcm-2) at various angular (Δ ϴ=0-51.3) and linear (∆s=1.6-2.56 m) displacements from the source were used to generate inactivation kinetics, using the model organism, Staphylococcus aureus. Additionally, twelve bacterial species were surface-seeded and light-exposed at a fixed displacement below the source (1.5 m; 0.5 mWcm-2) to demonstrate broad-spectrum efficacy at heights typical of high touch surfaces within occupied settings. Results Results demonstrate that significant (P≤0.05) inactivation was successfully achieved at all irradiance values investigated, with spatial positioning from the source affecting inactivation, with greater times required for inactivation as irradiance decreased. Complete/near-complete (≥93.28%) inactivation of all bacteria was achieved following exposure to 0.5 mWcm-2 within exposure times realistic of those utilised practically for whole-room decontamination (2-16 h). Conclusion This study provides fundamental evidence of the efficacy, and energy efficiency, of low irradiance 405-nm light for bacterial inactivation within a controlled laboratory setting, further justifying its benefits for practical infection control applications.
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Affiliation(s)
- Lucy G Sinclair
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies, Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Laura R Dougall
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies, Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Zornitsa Ilieva
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - Karen McKenzie
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies, Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - John G Anderson
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies, Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Scott J MacGregor
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies, Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Michelle Maclean
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies, Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
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8
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Inhibitory effect of 405 nm laser light on bacterial biofilm in urethral stent. Sci Rep 2023; 13:3908. [PMID: 36890147 PMCID: PMC9995349 DOI: 10.1038/s41598-023-30280-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 02/20/2023] [Indexed: 03/10/2023] Open
Abstract
The clinical use of urethral stents is usually complicated by various adverse effects, including dysuria, fever, and urinary tract infection (UTI). Biofilms (formed by bacteria, such as Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) adhering to the stent cause UTIs in stented patients (approximately 11%). The undesirable consequences of antibiotics use include bacterial resistance, weight gain, and type 1 diabetes, which occur when antibiotics are used for a long time. We aimed to assess the efficacy of a new optical treatment with a 405 nm laser to inhibit bacterial growth in a urethral stent in vitro. The urethral stent was grown in S. aureus broth media for three days to induce biofilm formation under dynamic conditions. Various irradiation times with the 405 nm laser light were tested (5, 10, and 15 min). The efficacy of the optical treatment on biofilms was evaluated quantitatively and qualitatively. The production of reactive oxygen species helped eliminate the biofilm over the urethral stent after 405 nm irradiation. The inhibition rate corresponded to a 2.2 log reduction of colony-forming units/mL of bacteria after 0.3 W/cm2 of irradiation for 10 min. The treated stent showed a significant reduction in biofilm formation compared with the untreated stent, as demonstrated by SYTO 9 and propidium iodide staining. MTT assays using the CCD-986sk cell line revealed no toxicity after 10 min of irradiation. We conclude that optical treatment with 405 nm laser light inhibits bacterial growth in urethral stents with no or minimal toxicity.
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Zhang W, Su P, Ma J, Gong M, Ma L, Wang J. A singlet state oxygen generation model based on the Monte Carlo method of visible antibacterial blue light inactivation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2023; 239:112628. [PMID: 36610348 DOI: 10.1016/j.jphotobiol.2022.112628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 11/22/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
Abstract
Visible antibacterial blue light (VABL) has received much attention recently as a nondestructive inactivation approach. However, due to the sparse distribution of bacteria, the light energy evaluation method used in existing studies is inaccurate. Thus, the sensitivity of microorganisms to VABL in different experiments cannot be compared. In this paper, a Monte Carlo-based photon transport model with the optimized scattering phase function was constructed. The model calculated the spatial light energy distribution and the temporal distribution of cumulative singlet state oxygen (CSO) under various cell and medium parameters. The simulation results show that when the cells are sparsely distributed, <30% of light energy from the light source is absorbed by microbes and participates in photochemical reactions. The CSO produced increases with cell density and cell size. Little light energy is available, and thus, the concentration of CSO produced is insufficient to inactivate microbes at deeper depths. As the light intensity and inactivation time increased, the production of singlet state oxygen tended to level off. The model proposed here can quantify the generation of singlet state oxygen and provide a more accurate light energy guide for the VABL inactivation process.
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Affiliation(s)
- Wanqing Zhang
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Ping Su
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Jianshe Ma
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
| | - Mali Gong
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China; Department of Precision Instrument, Tsinghua University, Beijing 100084, China
| | - Liya Ma
- Shenzhen Baoan Women and Children's Hospital, Jinan University, Shenzhen 518100, China
| | - Jing Wang
- College of Water Conservancy, Yunnan Agricultural University, Kunming 650000, China
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Messina G, Bosco R, Amodeo D, Nante N, De Palma I, Petri C, Cevenini G. Safer school with near-UV technology: novel applications for environmental hygiene. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2023; 21:157-165. [PMID: 36718267 PMCID: PMC9877489 DOI: 10.1007/s40201-023-00850-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 01/16/2023] [Indexed: 05/07/2023]
Abstract
Systems capable of disinfecting air and surfaces could reduce the risk of infectious diseases transmission. Aim: to evaluate the effectiveness of near-UV LED ceiling lamps, with a wavelength of 405 nm, in improving environmental hygiene. Between November and December 2020, we conducted an experimental study having a pre-post design in a kindergarten room in Siena where 4 ceiling lamps with 405 nm LED technology were installed. Twice per day, sampling was performed before (T0) and after treatment with near-UV (T1). We used between 8 and 12 pairs of contact plates to sample at various random spots each day. Air samplings were also performed. The plates were incubated at 22 and 36 °C. Significance was set at 95% (p < 0.05). The mean level of Colony Forming Unit (CFU) at T(0) was 249 (95% CI 193.1 - 305.0) at 36 °C and 535.2 (374.3 - 696.1) at 22 °C. The reduction was significant at T(1): by 65% at 36 °C and, 72% at 22 °C. Also, for air contamination: 95.3% (98.4-92.3). A dose threshold of about 5 J/cm2 was identified to have an 80% CFU abatement and remains nearly constant. The advantage of being able to use this technology in the presence of people is very important in the context of controlling environmental contamination. Graphical abstract
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Affiliation(s)
- G. Messina
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
- Post Graduate School of Public Health, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - R. Bosco
- Post Graduate School of Public Health, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - D. Amodeo
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - N. Nante
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
- Post Graduate School of Public Health, Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - I. De Palma
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - C. Petri
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - G. Cevenini
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
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11
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Amodeo D, Lucarelli V, De Palma I, Puccio A, Nante N, Cevenini G, Messina G. Efficacy of violet-blue light to inactive microbial growth. Sci Rep 2022; 12:20179. [PMID: 36424450 PMCID: PMC9691702 DOI: 10.1038/s41598-022-24563-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 11/17/2022] [Indexed: 11/26/2022] Open
Abstract
The increase in health care-associated infections and antibiotic resistance has led to a growing interest in the search for innovative technologies to solve these problems. In recent years, the interest of the scientific community has focused on violet-blue light at 405 nm (VBL405). This study aimed to assess the VBL405 efficiency in reducing microbial growth on surfaces and air. This descriptive study run between July and October 2020. Petri dishes were contaminated with P. aeruginosa, E. coli, S. aureus, S. typhimurium, K. pneumoniae and were placed at 2 and 3 m from a LED light source having a wavelength peak at 405 nm and an irradiance respectively of 967 and 497 µW/cm2. Simultaneously, the air in the room was sampled for 5 days with two air samplers (SAS) before and after the exposition to the VBL405 source. The highest microbial reduction was reached 2 m directly under the light source: S. typhimurium (2.93 log10), K. pneumoniae (2.30 log10), S. aureus (3.98 log10), E. coli (3.83 log10), P. aeruginosa (3.86 log10). At a distance of 3 m from the light source, the greatest reduction was observed for S. aureus (3.49 log10), and P. aeruginosa (3.80 log10). An average percent microbial reduction of about 70% was found in the sampled air after 12 h of exposure to VBL405. VBL405 has proven to contrast microbial growth on the plates. Implementing this technology in the environment to provide continuous disinfection and to control microbial presence, even in the presence of people, may be an innovative solution.
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Affiliation(s)
- Davide Amodeo
- grid.9024.f0000 0004 1757 4641Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Valentina Lucarelli
- grid.9024.f0000 0004 1757 4641Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Isa De Palma
- grid.9024.f0000 0004 1757 4641Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Alessandro Puccio
- grid.9024.f0000 0004 1757 4641Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Nicola Nante
- grid.9024.f0000 0004 1757 4641Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Gabriele Cevenini
- grid.9024.f0000 0004 1757 4641Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Gabriele Messina
- grid.9024.f0000 0004 1757 4641Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
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12
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Metzger M, Hacobian A, Karner L, Krausgruber L, Grillari J, Dungel P. Resistance of Bacteria toward 475 nm Blue Light Exposure and the Possible Role of the SOS Response. Life (Basel) 2022; 12:1499. [PMID: 36294934 PMCID: PMC9605056 DOI: 10.3390/life12101499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 11/07/2023] Open
Abstract
The increase in antibiotic resistance represents a major global challenge for our health systems and calls for alternative treatment options, such as antimicrobial light-based therapies. Blue light has shown promising results regarding the inactivation of a variety of microorganisms; however, most often, antimicrobial blue light (aBL) therapy is performed using wavelengths close to the UV range. Here we investigated whether inactivation was possible using blue light with a wavelength of 475 nm. Both Gram-positive and -negative bacterial strains were treated with blue light with fluences of 7.5-45 J/cm2. Interestingly, only some bacterial strains were susceptible to 475 nm blue light, which was associated with the lack of RecA, i.e., a fully functional DNA repair mechanism. We demonstrated that the insertion of the gene recA reduced the susceptibility of otherwise responsive bacterial strains, indicating a protective mechanism conveyed by the bacterial SOS response. However, mitigating this pathway via three known RecA inhibiting molecules (ZnAc, curcumin, and Fe(III)-PcTs) did not result in an increase in bactericidal action. Nonetheless, creating synergistic effects by combining a multitarget therapy, such as aBL, with an RecA targeting treatment could be a promising strategy to overcome the dilemma of antibiotic resistance in the future.
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Affiliation(s)
- Magdalena Metzger
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
- Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, 1190 Vienna, Austria
| | - Ara Hacobian
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Lisa Karner
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Leonie Krausgruber
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
| | - Johannes Grillari
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
- Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, 1190 Vienna, Austria
| | - Peter Dungel
- Ludwig Boltzmann Institute for Traumatology, The Research Center in Cooperation with AUVA, 1200 Vienna, Austria
- Austrian Cluster for Tissue Regeneration, 1200 Vienna, Austria
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13
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Bang JI, Kim JH, Choi A, Sung M. The Wavelength-Based Inactivation Effects of a Light-Emitting Diode Module on Indoor Microorganisms. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:9659. [PMID: 35955018 PMCID: PMC9368635 DOI: 10.3390/ijerph19159659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/03/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
With the increased incidence of infectious disease outbreaks in recent years such as the COVID-19 pandemic, related research is being conducted on the need to prevent their spread; it is also necessary to develop more general physical-chemical control methods to manage them. Consequently, research has been carried out on light-emitting diodes (LEDs) as an effective means of light sterilization. In this study, the sterilization effects on four types of representative bacteria and mold that occur indoors, Bacillus subtilis, Escherichia coli, Penicillium chrysogenum, and Cladosporium cladosporidides, were confirmed using LED modules (with wavelengths of 275, 370, 385, and 405 nm). Additionally, power consumption was compared by calculating the time required for 99.9% sterilization of each microorganism. The results showed that the sterilization effect was high, in the order 275, 370, 385, and 405 nm. The sterilization effects at 385 and 405 nm were observed to be similar. Furthermore, when comparing the power consumption required for 99.9% sterilization of each microorganism, the 275 nm LED module required significantly less power than those of other wavelengths. However, at 405 nm, the power consumption required for 99.9% sterilization was less than that at 370 nm; that is, it was more efficient and similar to or less than that at 385 nm. Additionally, because 405 nm can be applied as general lighting, it was considered to have wider applicability and utility compared with UV wavelengths. Consequently, it should be possible to respond to infectious diseases in the environment using LEDs with visible light wavelengths.
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Affiliation(s)
- Jong-Il Bang
- Department of Architectural Engineering, Sejong University, 209 Neungdong-Ro, Gwangjin-Gu, Seoul 05006, Korea
| | - Ji-Hi Kim
- Specialization Strategy Technology Department, EAN Technology Co., Ltd., EAN Institute of Sustainable Technology, 77-gil Teheran-Ro, Gangnam-Gu, Seoul 06159, Korea
| | - Anseop Choi
- Department of Architectural Engineering, Sejong University, 209 Neungdong-Ro, Gwangjin-Gu, Seoul 05006, Korea
| | - Minki Sung
- Department of Architectural Engineering, Sejong University, 209 Neungdong-Ro, Gwangjin-Gu, Seoul 05006, Korea
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14
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Efficacy of 405 nm Light-Emitting Diode Illumination and Citral Used Alone and in Combination for Inactivation of Vibrio parahaemolyticus on Shrimp. Foods 2022; 11:foods11142008. [PMID: 35885251 PMCID: PMC9324625 DOI: 10.3390/foods11142008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 06/29/2022] [Accepted: 06/30/2022] [Indexed: 02/01/2023] Open
Abstract
Vibrio parahaemolyticus is a widely distributed pathogen, which is frequently the lead cause of infections related to seafood consumption. The objective of the present study was to investigate the antimicrobial effect of the combination of 405 nm light-emitting diode (LED) and citral on V. parahaemolyticus. The antimicrobial effect of LED illumination and citral was evaluated on V. parahaemolyticus not only in phosphate-buffered saline (PBS) but also on shrimp. Quality changes of shrimp were determined by sensory evaluation. Changes in bacteria cell membrane morphology, cell membrane permeability, cell lipid oxidation level, and DNA degradation were examined to provide insights into the antimicrobial mechanism. The combination of LED treatments and citral had better antimicrobial effects than either treatment alone. LED combined with 0.1 mg/mL of citral effectively reduced V. parahaemolyticus from 6.5 log CFU/mL to below the detection limit in PBS. Combined treatment caused a 3.5 log reduction of the pathogen on shrimp within 20 min and a 6 log reduction within 2 h without significant changes in the sensory score. Furthermore, combined LED and citral treatment affected V. parahaemolyticus cellular morphology and outer membrane integrity. The profile of the comet assay and DNA fragmentation analysis revealed that combination treatment did not cause a breakdown of bacterial genomic DNA. In conclusion, LED may act synergistically with citral. They have the potential to be developed as novel microbial intervention strategies.
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15
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Growth medium- and strain-dependent bactericidal efficacy of blue light against Shiga toxin-producing Escherichia coli on food-grade stainless steel and plastic. Food Microbiol 2022; 103:103953. [DOI: 10.1016/j.fm.2021.103953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 10/25/2021] [Accepted: 11/19/2021] [Indexed: 11/18/2022]
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16
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Wang Y, Ge P, Guo X, He Y, Han X, Peng X, Wang Y, Xia X, Shi C. Inactivation of Shigella flexneri by 405-nm Light-Emitting Diode Treatment and Possible Mechanism of Action. Foodborne Pathog Dis 2022; 19:349-358. [PMID: 35443788 DOI: 10.1089/fpd.2021.0094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Shigella flexneri, a common Gram-negative foodborne pathogen, is widely distributed in fresh-cut fruits and vegetables, unpasteurized milk, and food processing environments. The aims of this study were to evaluate the antibacterial effects of 405-nm light-emitting diode (LED) treatment on S. flexneri and to investigate the possible mechanism. The results showed that LED irradiation (360 min) reduced the number of S. flexneri in phosphate-buffered saline by 3.29 log colony-forming unit (CFU)/mL (initial bacterial count: 6.81 log CFU/mL). The cells in reconstituted infant formula, cells on fresh-cut carrot slices, and biofilm-associated cells on stainless steel surfaces were reduced by 1.83 log CFU/mL, 7.00 log CFU/cm2, and 4.35 log CFU/cm2 following LED treatment for 360, 120, and 120 min, respectively. LED treatment damaged both DNA and cell wall of S. flexneri and changed cell morphology and cell membrane permeability. In addition, LED treatment decreased total cell protein concentration of S. flexneri. These results indicated that 405-nm LED treatment effectively controlled S. flexneri contamination of foods and food contact surfaces and that the bacterial inactivation may be the result of damage to multiple cellular components. These findings highlight the potential of LED technology in controlling S. flexneri during food processing, storage, and preparation.
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Affiliation(s)
- Yiwen Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Pengfei Ge
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Xi Guo
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Yifei He
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Xintong Han
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiaoli Peng
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Yutang Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiaodong Xia
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
| | - Chao Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, China
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17
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Yu X, Zheng P, Zou Y, Ye Z, Wei T, Lin J, Guo L, Yuk HG, Zheng Q. A review on recent advances in LED-based non-thermal technique for food safety: current applications and future trends. Crit Rev Food Sci Nutr 2022; 63:7692-7707. [PMID: 35369810 DOI: 10.1080/10408398.2022.2049201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Light-emitting diodes (LEDs) is an eco-friendly light source with broad-spectrum antimicrobial activity. Recent studies have extensively been conducted to evaluate its efficacy in microbiological safety and the potential as a preservation method to extend the shelf-life of foods. This review aims to present the latest update of recent studies on the basics (physical, biochemical and mechanical basics) and antimicrobial activity of LEDs, as well as its application in the food industry. The highlight will be focused on the effects of LEDs on different types (bacteria, yeast/molds, viruses) and forms (planktonic cells, biofilms, endospores, fungal toxin) of microorganisms. The antimicrobial activity of LEDs on various food matrices was also evaluated, together with further analysis on the food-related factors that lead to the differences in LEDs efficiency. Besides, the applications of LEDs on the food-related conditions, packaged food, and equipment that could enhance LEDs efficiency were discussed to explore the future trends of LEDs technology in the food industry. Overall, the present review provides important insights for future research and the application of LEDs in the food industry.
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Affiliation(s)
- Xinpeng Yu
- College of Food Science & Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Peng Zheng
- College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Yuan Zou
- College of Food Science & Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Zhiwei Ye
- College of Food Science & Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Tao Wei
- College of Food Science & Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Junfang Lin
- College of Food Science & Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Liqiong Guo
- College of Food Science & Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
| | - Hyun-Gyun Yuk
- Department of Food Science and Technology, Korea National University of Transportation, Chungbuk, Republic of Korea
| | - Qianwang Zheng
- College of Food Science & Institute of Food Biotechnology, South China Agricultural University, Guangzhou, China
- Research Center for Micro-Ecological Agent Engineering and Technology of Guangdong Province, Guangzhou, China
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18
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de Oliveira Assunção FF, Nascimento É, Chaves L, da Silva AMH, Martinez R, de Jesus Guirro RR. Inhibition of bacterial growth through LED (light-emitting diode) 465 and 630 nm: in vitro. Lasers Med Sci 2022; 37:2439-2447. [PMID: 35075597 DOI: 10.1007/s10103-022-03505-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 01/06/2022] [Indexed: 11/29/2022]
Abstract
Photobiomodulation has been used to inactivate bacterial growth, in different laser or LED protocols. Thus, the aim of this study was to verify the inhibition of Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, in ATCC strains and bacteria collected from patients with skin burns, after irradiation with LED; 300 μl of saline solution with bacterial suspension was irradiated at a concentration of 0.5-0.63, by the McFarland scale, after five serial dilutions, with evaluation of pre- and post-irradiation pH and temperature control. The cultures were placed in a bacteriological incubator at 37 °C for 24 h for later counting of colony-forming units (CFU). Data were analyzed by Shapiro-Wilk tests and single-factor ANOVA, with Tukey post hoc (p < 0.05). Both wavelengths and energy densities tested showed inhibition of bacterial growth. The comparison of the irradiated groups (ATCC) with the control group showed the following: S. aureus and P. aeruginosa 465 nm (40 J/cm2) and 630 nm (50 J/cm2) and E. coli 465 nm (40 J/cm2) and 630 nm (30 J/cm2). Among the ATCC S. aureus groups, there was a difference for 630 nm (30 J/cm2) and 465 nm (30, 40, 50 J/cm2). The bacteria from the burned patients were S. aureus (30 and 50 J/cm2) and P. aeruginosa (50 J/cm2). We conclude that different bacterial strains were reduced into colony-forming units after LED irradiation.
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Affiliation(s)
- Flávia Fernanda de Oliveira Assunção
- Department of Health Sciences, Ribeirão Preto Medical School, University of São Paulo, Avenida Bandeirantes, 3900 - Ribeirão Preto, SP, CEP, 14049-900, Brazil
| | - Érika Nascimento
- Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Lucas Chaves
- Graduate Program in Public Health, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Alessandro Márcio Hakme da Silva
- Center for Engineering Applied To Heath School of Engineering of São Carlos, Postdoctoral Researcher, University of São Paulo, São Carlos, SP, Brazil
| | - Roberto Martinez
- Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Rinaldo Roberto de Jesus Guirro
- Department of Health Sciences, Ribeirão Preto Medical School, University of São Paulo, Avenida Bandeirantes, 3900 - Ribeirão Preto, SP, CEP, 14049-900, Brazil.
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19
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Tran VN, Park S, Khan F, Truong VG, Jeong S, Lee DH, Kim YM, Kang HW. Collective bacterial disinfection by opto-chemical treatment on mature biofilm in clinical endoscope. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2022; 226:112367. [PMID: 34847498 DOI: 10.1016/j.jphotobiol.2021.112367] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/12/2021] [Accepted: 11/17/2021] [Indexed: 02/07/2023]
Abstract
The present study proposes an innovative opto-chemical treatment using a basket-integrated optical device (BIOD) to disinfect mature bacterial biofilm on endoscope channels. A BIOD was designed to position an optical diffuser on the central axis of an endoscope channel and to distribute laser light concentrically to the bacterial biofilm on the channel surface. To apply thermal damage and oxidative stress to the bacterial biofilm, a low concentration of a crosslinking agent (glutaraldehyde ~0.5%) was combined with 808 nm infrared (IR) and 405 nm blue (BL) laser lights. The applied irradiances of IR and BL were 10 W/cm2 and 1.6 W/cm2 for Teflon channel model and 20 W/cm2 and 3.2 W/cm2 for a clinical model, respectively. Individual irradiation of either IR or BL for 180 s induced the maximum temperatures of 62 ± 2 °C and 53 ± 3 °C on the biofilm, respectively. The simultaneous opto-chemical treatment reduced a significant population of the bacterial biofilms (7.5-log10 for Staphylococcus aureus and 7.1-log10 for Pseudomonas aeruginosa), which were 2.9-fold and 3.9-fold higher than that of the standard treatment with 2% glutaraldehyde (GA) solution, respectively. The proposed opto-chemical disinfection method can help reduce multi-drug resistant bacteria and prevent cross-infection during the clinical usage of a flexible endoscope.
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Affiliation(s)
- Van Nam Tran
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, South Korea
| | - Suhyun Park
- Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, South Korea
| | - Fazlurrahman Khan
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan 48513, South Korea
| | - Van Gia Truong
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, South Korea
| | - Seok Jeong
- Division of Gastroenterology, Department of Internal Medicine, Inha University College of Medicine, Incheon 22212, South Korea
| | - Don Haeng Lee
- Division of Gastroenterology, Department of Internal Medicine, Inha University College of Medicine, Incheon 22212, South Korea
| | - Young-Mog Kim
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan 48513, South Korea; Department of Food Science and Technology, Pukyong National University, Busan 48513, South Korea
| | - Hyun Wook Kang
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, South Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan 48513, South Korea; Department of Biomedical Engineering, Pukyong National University, Busan 48513, South Korea.
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20
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KEYVAN E, KAHRAMAN HA, TUTUN H, DONMEZ S, SEN E, DEMIRTAS A, AKYUZ AO. Inactivation efficacy of 405 nm light emitting diodes (LEDs) on Salmonella Enteritidis at different illumination temperatures. FOOD SCIENCE AND TECHNOLOGY 2022. [DOI: 10.1590/fst.08721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
| | | | | | | | - Erdi SEN
- Burdur Mehmet Akif Ersoy University, Turkey
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21
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Stewart CF, Tomb RM, Ralston HJ, Armstrong J, Anderson JG, MacGregor SJ, Atreya CD, Maclean M. Violet-blue 405-nm Light-based Photoinactivation for Pathogen Reduction of Human Plasma Provides Broad Antibacterial Efficacy Without Visible Degradation of Plasma Proteins. Photochem Photobiol 2021; 98:504-512. [PMID: 34935147 DOI: 10.1111/php.13584] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/15/2021] [Indexed: 11/28/2022]
Abstract
In transfusion medicine, bacterial contamination can occur in ex vivo stored blood plasma, and there are continued efforts to improve blood safety and reduce the risk of transfusion-transmitted infections. Visible 405-nm violet-blue light has demonstrated potential for in situ pathogen reduction in ex vivo stored plasma and platelet concentrates. This study investigates the broad-spectrum antibacterial efficacy and compatibility potential of 405-nm light for treatment of blood plasma. Human plasma seeded with bacteria at a range of densities (101 -103 , 104 -106 , 107 -108 CFU mL-1 ) was exposed to 360 J cm-2 405-nm light (1 h at 0.1 W cm-2 ), with this fixed dose selected based on the initial analysis of inactivation kinetics. One-dimensional protein mobility analysis and measurement of advanced oxidation protein products (AOPP) was conducted to evaluate compatibility of the antimicrobial dose with plasma proteins and, identify upper levels at which protein degradation can be detected. Broad-spectrum antibacterial efficacy was observed with a fixed treatment of 360 J cm-2 , with 98.9-100% inactivation achieved across all seeding densities for all organisms, except E. coli, which achieved 95.1-100% inactivation. At this dose (360 J cm-2 ), no signs of protein degradation occurred. Overall, 405-nm light shows promise for broad-spectrum bacterial inactivation in blood plasma, while preserving plasma protein integrity.
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Affiliation(s)
- Caitlin F Stewart
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Rachael M Tomb
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Heather J Ralston
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - Jack Armstrong
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - John G Anderson
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Scott J MacGregor
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK
| | - Chintamani D Atreya
- Office of Blood Research and Review, Center for Biologics Evaluation and Research (CBER), Food and Drug Administration, Silver Spring, MD
| | - Michelle Maclean
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST), Department of Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK.,Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
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22
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Wang D, Kuzma ML, Tan X, He TC, Dong C, Liu Z, Yang J. Phototherapy and optical waveguides for the treatment of infection. Adv Drug Deliv Rev 2021; 179:114036. [PMID: 34740763 PMCID: PMC8665112 DOI: 10.1016/j.addr.2021.114036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 10/11/2021] [Accepted: 10/28/2021] [Indexed: 02/07/2023]
Abstract
With rapid emergence of multi-drug resistant microbes, it is imperative to seek alternative means for infection control. Optical waveguides are an auspicious delivery method for precise administration of phototherapy. Studies have shown that phototherapy is promising in fighting against a myriad of infectious pathogens (i.e. viruses, bacteria, fungi, and protozoa) including biofilm-forming species and drug-resistant strains while evading treatment resistance. When administered via optical waveguides, phototherapy can treat both superficial and deep-tissue infections while minimizing off-site effects that afflict conventional phototherapy and pharmacotherapy. Despite great therapeutic potential, exact mechanisms, materials, and fabrication designs to optimize this promising treatment option are underexplored. This review outlines principles and applications of phototherapy and optical waveguides for infection control. Research advances, challenges, and outlook regarding this delivery system are rigorously discussed in a hope to inspire future developments of optical waveguide-mediated phototherapy for the management of infection and beyond.
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Affiliation(s)
- Dingbowen Wang
- Department of Biomedical Engineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Michelle Laurel Kuzma
- Department of Biomedical Engineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Xinyu Tan
- Department of Biomedical Engineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA; Academy of Orthopedics, Provincial Key Laboratory of Bone and Joint Degenerative Diseases, The Third Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong Province 510280, China
| | - Tong-Chuan He
- Molecular Oncology Laboratory, Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA; Department of Surgery, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Cheng Dong
- Department of Biomedical Engineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Zhiwen Liu
- Department of Electrical Engineering, Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jian Yang
- Department of Biomedical Engineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA.
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23
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Wang D, Kyere E, Ahmed Sadiq F. New Trends in Photodynamic Inactivation (PDI) Combating Biofilms in the Food Industry-A Review. Foods 2021; 10:2587. [PMID: 34828868 PMCID: PMC8621587 DOI: 10.3390/foods10112587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/19/2021] [Accepted: 10/22/2021] [Indexed: 12/26/2022] Open
Abstract
Biofilms cause problems in the food industry due to their persistence and incompetent hygiene processing technologies. Interest in photodynamic inactivation (PDI) for combating biofilms has increased in recent years. This technique can induce microbial cell death, reduce cell attachment, ruin biofilm biomolecules and eradicate structured biofilms without inducing microbial resistance. This review addresses microbial challenges posed by biofilms in food environments and highlights the advantages of PDI in preventing and eradicating microbial biofilm communities. Current findings of the antibiofilm efficiencies of this technique are summarized. Additionally, emphasis is given to its potential mechanisms and factors capable of influencing biofilm communities, as well as promising hurdle strategies.
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Affiliation(s)
- Dan Wang
- School of Food and Advanced Technology, Massey University, Palmerston North 4410, New Zealand;
| | - Emmanuel Kyere
- School of Food and Advanced Technology, Massey University, Palmerston North 4410, New Zealand;
| | - Faizan Ahmed Sadiq
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China;
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24
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Tran VN, Saravana PS, Park S, Truong VG, Chun BS, Kang HW. Opto-chemical treatment for enhanced high-level disinfection of mature bacterial biofilm in a Teflon-based endoscope model. BIOMEDICAL OPTICS EXPRESS 2021; 12:5736-5750. [PMID: 34692212 PMCID: PMC8515982 DOI: 10.1364/boe.434047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/25/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
Medical societies and public health agencies rigorously emphasize the importance of adequate disinfection of flexible endoscopes. The aim of this work was to propose a novel opto-chemical disinfection treatment against Staphylococcus aureus grown in mature biofilm on Teflon-based endoscope channel models. Laser irradiation using near-infrared and blue wavelengths combined with a low concentration of chemical disinfectant induced both irreversible thermal denaturation and intercellular oxidative stress as a combined mechanism for an augmented antimicrobial effect. The opto-chemical method yielded a 6.7-log10 reduction of the mature Staphylococcus aureus biofilms (i.e., approximately 1.0-log10 higher than current requirement of standard treatment). The proposed technique may be a feasible disinfection method for mitigating the risk associated with infection transmission.
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Affiliation(s)
- Van Nam Tran
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan, 48513, Republic of Korea
- These authors contributed equally to this work
| | - Periaswamy Sivagnanam Saravana
- Department of Food Science and Technology, Pukyong National University, Busan 48513, Republic of Korea
- These authors contributed equally to this work
| | - Suhyun Park
- Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Van Gia Truong
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan, 48513, Republic of Korea
| | - Byung-Soo Chun
- Department of Food Science and Technology, Pukyong National University, Busan 48513, Republic of Korea
| | - Hyun Wook Kang
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan, 48513, Republic of Korea
- Department of Biomedical Engineering and Marine-integrated Biomedical Technology Center, Pukyong National University, Busan 48513, Republic of Korea
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25
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NIR Irradiation Based on Low-Power LED Drive Module Design for Fat Reduction. BIOMED RESEARCH INTERNATIONAL 2021; 2021:9992095. [PMID: 34423044 PMCID: PMC8378979 DOI: 10.1155/2021/9992095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/26/2021] [Indexed: 11/17/2022]
Abstract
In this study, we designed a low-power visible ray (V) drive module based on a light-emitting diode (LED) to initiate fat reduction using light source irradiation. A chemical phantom of muscle and fat was fabricated, and the performance of the proposed LED drive module was tested using this chemical phantom. The LED light source could reduce fat by irradiating the skin 4–5 cm deep. The device exhibits a negative feedback and parallel amplification to maintain a stable circuit based on low-power consumption. Muscles have a high-water content and low impedance, whereas fats have a low water content and significant salt content. Therefore, fat exhibits high impedance. Chemical phantoms were fabricated according to these impedance values, and the fat reduction effect using the LED circuits was analyzed. When the fat phantom was irradiated by the light source, the fat impedance lowered, and we confirmed that fat reduction could be obtained. This study is expected to be applicable to family medicine and weight management health care.
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26
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Zhang Y, Xie J. Effects of 405 nm light‐emitting diode treatment on microbial community on fresh‐cut pakchoi and antimicrobial action against
Pseudomonas reinekei
and
Pseudomonas palleroniana. J Food Saf 2021. [DOI: 10.1111/jfs.12920] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yuchen Zhang
- College of Food Science and Technology Shanghai Ocean University Shanghai China
- National Experimental Teaching Demonstration Center for Food Science and Engineering Shanghai Ocean University Shanghai China
| | - Jing Xie
- College of Food Science and Technology Shanghai Ocean University Shanghai China
- National Experimental Teaching Demonstration Center for Food Science and Engineering Shanghai Ocean University Shanghai China
- Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation Shanghai China
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Bajaj AO, Saraswat S, Knuuttila JEA, Freeke J, Stielow JB, Barker AP. Accurate Identification of Closely Related Mycobacterium tuberculosis Complex Species by High Resolution Tandem Mass Spectrometry. Front Cell Infect Microbiol 2021; 11:656880. [PMID: 34239815 PMCID: PMC8259740 DOI: 10.3389/fcimb.2021.656880] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 05/07/2021] [Indexed: 11/22/2022] Open
Abstract
Rapid and accurate differentiation of Mycobacterium tuberculosis complex (MTBC) species from other mycobacterium is essential for appropriate therapeutic management, timely intervention for infection control and initiation of appropriate health care measures. However, routine clinical characterization methods for Mycobacterium tuberculosis (Mtb) species remain both, time consuming and labor intensive. In the present study, an innovative liquid Chromatography-Mass Spectrometry method for the identification of clinically most relevant Mycobacterium tuberculosis complex species is tested using a model set of mycobacterium strains. The methodology is based on protein profiling of Mycobacterium tuberculosis complex isolates, which are used as markers of differentiation. To test the resolving power, speed, and accuracy of the method, four ATCC type strains and 37 recent clinical isolates of closely related species were analyzed using this new approach. Using different deconvolution algorithms, we detected hundreds of individual protein masses, with a subpopulation of these functioning as species-specific markers. This assay identified 216, 260, 222, and 201 proteoforms for M. tuberculosis ATCC 27294™, M. microti ATCC 19422™, M. africanum ATCC 25420™, and M. bovis ATCC 19210™ respectively. All clinical strains were identified to the correct species with a mean of 95% accuracy. Our study successfully demonstrates applicability of this novel mass spectrometric approach to identify clinically relevant Mycobacterium tuberculosis complex species that are very closely related and difficult to differentiate with currently existing methods. Here, we present the first proof-of-principle study employing a fast mass spectrometry-based method to identify the clinically most prevalent species within the Mycobacterium tuberculosis species complex.
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Affiliation(s)
- Amol O Bajaj
- Research & Development, Associated Regional and University Pathologists, Inc. (ARUP) Institute for Clinical and Experimental Pathology, Salt Lake City, UT, United States
| | - Suraj Saraswat
- Research & Development, Associated Regional and University Pathologists, Inc. (ARUP) Institute for Clinical and Experimental Pathology, Salt Lake City, UT, United States
| | - Juha E A Knuuttila
- Research & Development, Thermo Fisher Scientific, Helsinki-Vantaa, Finland
| | - Joanna Freeke
- Centre for Infectious Diseases, Radboud University Medical Center (UMC), Nijmegen, Netherlands.,Research & Development, Thermo Fisher Scientific, Landsmeer, Netherlands
| | - J Benjamin Stielow
- Centre for Infectious Diseases, Radboud University Medical Center (UMC), Nijmegen, Netherlands.,Research & Development, Thermo Fisher Scientific, Landsmeer, Netherlands
| | - Adam P Barker
- Research & Development, Associated Regional and University Pathologists, Inc. (ARUP) Institute for Clinical and Experimental Pathology, Salt Lake City, UT, United States
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28
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Photoinactivation of mycobacteria to combat infection diseases: current state and perspectives. Appl Microbiol Biotechnol 2021; 105:4099-4109. [PMID: 33997929 PMCID: PMC8126513 DOI: 10.1007/s00253-021-11349-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/04/2021] [Accepted: 05/09/2021] [Indexed: 12/11/2022]
Abstract
Abstract The spread of multi-drug-resistant bacterial strains causing serious infectious diseases dictates the development of new approaches to combat these diseases. In addition to drug resistance, the important causative agent of tuberculosis (Mycobacterium tuberculosis (Mtb)) is able to persist asymptomatically in individuals for many years, causing latent forms of tuberculosis. In such a dormant state, Mtb cells are also resistant to known antibiotics. In this regard, photodynamic inactivation (PDI) could be an effective alternative to antibiotics as its action is based on the generation of active forms of oxygen independently on the presence of specific antibiotic targets, thereby inactivating both drug-resistant and dormant bacteria. In this review, we summarise examples of the application of PDI for the elimination of representatives of the genus Mycobacteria, both in vitro and in vivo. According to published results, including photosensitisers in the PDI regime results in a significantly higher lethal effect. Such experiments were mainly performed using chemically synthesised photosensitisers, which need to be transported to the areas of bacterial infections, limiting PDI usage by surface (skin) diseases. In this regard, endogenous photosensitisers (mainly porphyrins) could be used to solve the problem of transportation. In vitro experiments demonstrate the effective application of PDI for mycobacteria, including Mtb, using endogenous porphyrins; the intracellular contents of these substances can be elevated by administration of 5-aminolevulenic acid, a precursor of porphyrin synthesis. Photodynamic inactivation can also be used for dormant mycobacteria, which are characterised by high levels of endogenous porphyrins. Thus, PDI can effectively eliminate drug-resistant mycobacteria. The exploitation of modern light-transmitting techniques opens new possibilities to use PDI in clinical settings. Key points •The potential effects of photodynamic inactivation of mycobacteria are critically reviewed. •Approaches to photoinactivation of mycobacteria using exogenous and endogenous photosensitisers are described. •Prospects for the use of photodynamic inactivation in the treatment of tuberculosis are discussed.
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Photoinactivation of Staphylococci with 405 nm Light in a Trachea Model with Saliva Substitute at 37 °C. Healthcare (Basel) 2021; 9:healthcare9030310. [PMID: 33799642 PMCID: PMC7998829 DOI: 10.3390/healthcare9030310] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/28/2021] [Accepted: 03/04/2021] [Indexed: 02/03/2023] Open
Abstract
The globally observed rise in bacterial resistance against antibiotics has increased the need for alternatives to antibiotic treatments. The most prominent and important pathogen bacteria are the ESKAPE pathogens, which include among others Staphylococcus aureus, Klebsiella pneumoniae and Acinetobacter baumannii. These species cause ventilator-associated pneumonia (VAP), which accounts for 24% of all nosocomial infections. In this study we tested the efficacy of photoinactivation with 405 nm violet light under conditions comparable to an intubated patient with artificial saliva for bacterial suspension at 37 °C. A technical trachea model was developed to investigate the visible light photoinactivation of Staphylococcus carnosus as a non-pathogen surrogate of the ESKAPE pathogen S. aureus (MRSA). The violet light was coupled into the tube with a fiber optic setup. The performed tests proved, that photoinactivation at 37 °C is more effective with a reduction of almost 3 log levels (99.8%) compared to 25 °C with a reduction of 1.2 log levels. The substitution of phosphate buffered saline (PBS) by artificial saliva solution slightly increased the efficiency during the experimental course. The increased efficiency might be caused by a less favorable environment for bacteria due to for example the ionic composition.
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30
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Hadi J, Wu S, Brightwell G. Antimicrobial Blue Light versus Pathogenic Bacteria: Mechanism, Application in the Food Industry, Hurdle Technologies and Potential Resistance. Foods 2020; 9:E1895. [PMID: 33353056 PMCID: PMC7767196 DOI: 10.3390/foods9121895] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/12/2020] [Accepted: 12/16/2020] [Indexed: 12/12/2022] Open
Abstract
Blue light primarily exhibits antimicrobial activity through the activation of endogenous photosensitizers, which leads to the formation of reactive oxygen species that attack components of bacterial cells. Current data show that blue light is innocuous on the skin, but may inflict photo-damage to the eyes. Laboratory measurements indicate that antimicrobial blue light has minimal effects on the sensorial and nutritional properties of foods, although future research using human panels is required to ascertain these findings. Food properties also affect the efficacy of antimicrobial blue light, with attenuation or enhancement of the bactericidal activity observed in the presence of absorptive materials (for example, proteins on meats) or photosensitizers (for example, riboflavin in milk), respectively. Blue light can also be coupled with other treatments, such as polyphenols, essential oils and organic acids. While complete resistance to blue light has not been reported, isolated evidence suggests that bacterial tolerance to blue light may occur over time, especially through gene mutations, although at a slower rate than antibiotic resistance. Future studies can aim at characterizing the amount and type of intracellular photosensitizers across bacterial species and at assessing the oxygen-independent mechanism of blue light-for example, the inactivation of spoilage bacteria in vacuum-packed meats.
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Affiliation(s)
- Joshua Hadi
- AgResearch Ltd., Hopkirk Research Institute, Cnr University and Library Road, Massey University, Palmerston North 4442, New Zealand; (J.H.); (S.W.)
| | - Shuyan Wu
- AgResearch Ltd., Hopkirk Research Institute, Cnr University and Library Road, Massey University, Palmerston North 4442, New Zealand; (J.H.); (S.W.)
| | - Gale Brightwell
- AgResearch Ltd., Hopkirk Research Institute, Cnr University and Library Road, Massey University, Palmerston North 4442, New Zealand; (J.H.); (S.W.)
- New Zealand Food Safety Science and Research Centre, Tennent Drive, Massey University, Palmerston North 4474, New Zealand
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31
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Angarano V, Akkermans S, Smet C, Chieffi A, Van Impe JF. The potential of violet, blue, green and red light for the inactivation of P. fluorescens as planktonic cells, individual cells on a surface and biofilms. FOOD AND BIOPRODUCTS PROCESSING 2020. [DOI: 10.1016/j.fbp.2020.07.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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32
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Sæbø Pettersen K, Sundaram AYM, Skjerdal T, Wasteson Y, Kijewski A, Lindbäck T, Aspholm M. Exposure to Broad-Spectrum Visible Light Causes Major Transcriptomic Changes in Listeria monocytogenes EGDe. Appl Environ Microbiol 2019; 85:e01462-19. [PMID: 31492665 PMCID: PMC6821972 DOI: 10.1128/aem.01462-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 08/09/2019] [Indexed: 01/22/2023] Open
Abstract
Listeria monocytogenes, the causative agent of the serious foodborne disease listeriosis, can rapidly adapt to a wide range of environmental stresses, including visible light. This study shows that exposure of the L. monocytogenes EGDe strain to low-intensity, broad-spectrum visible light inhibited bacterial growth and caused altered multicellular behavior during growth on semisolid agar compared to when the bacteria were grown in complete darkness. These light-dependent changes were observed regardless of the presence of the blue light receptor (Lmo0799) and the stressosome regulator sigma B (SigB), which have been suggested to be important for the ability of L. monocytogenes to respond to blue light. A genome-wide transcriptional analysis revealed that exposure of L. monocytogenes EGDe to broad-spectrum visible light caused altered expression of 2,409 genes belonging to 18 metabolic pathways compared to bacteria grown in darkness. The light-dependent differentially expressed genes are involved in functions such as glycan metabolism, cell wall synthesis, chemotaxis, flagellar synthesis, and resistance to oxidative stress. Exposure to light conferred reduced bacterial motility in semisolid agar, which correlates well with the light-dependent reduction in transcript levels of flagellar and chemotaxis genes. Similar light-induced reduction in growth and motility was also observed in two different L. monocytogenes food isolates, suggesting that these responses are typical for L. monocytogenes Together, the results show that even relatively small doses of broad-spectrum visible light cause genome-wide transcriptional changes, reduced growth, and motility in L. monocytogenesIMPORTANCE Despite major efforts to control L. monocytogenes, this pathogen remains a major problem for the food industry, where it poses a continuous risk of food contamination. The ability of L. monocytogenes to sense and adapt to different stressors in the environment enables it to persist in many different niches, including food production facilities and in food products. The present study shows that exposure of L. monocytogenes to low-intensity broad-spectrum visible light reduces its growth and motility and alters its multicellular behavior. Light exposure also caused genome-wide changes in transcript levels, affecting multiple metabolic pathways, which are likely to influence the bacterial physiology and lifestyle. In practical terms, the data presented in this study suggest that broad-spectrum visible light is an important environmental variable to consider as a strategy to improve food safety by reducing L. monocytogenes contamination in food production environments.
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Affiliation(s)
- Kristin Sæbø Pettersen
- Norwegian Veterinary Institute, Oslo, Norway
- Norwegian University of Life Sciences, Oslo, Norway
| | - Arvind Y M Sundaram
- Norwegian Sequencing Centre, Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
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33
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Dorey AL, Lee BH, Rotter B, O'Byrne CP. Blue Light Sensing in Listeria monocytogenes Is Temperature-Dependent and the Transcriptional Response to It Is Predominantly SigB-Dependent. Front Microbiol 2019; 10:2497. [PMID: 31798538 PMCID: PMC6874125 DOI: 10.3389/fmicb.2019.02497] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 10/16/2019] [Indexed: 11/17/2022] Open
Abstract
Listeria monocytogenes is an important food-borne pathogen that is tolerant to many of the stresses commonly used during food preservation. Outside the host, the bacterium has a saprophytic lifestyle that includes periodic exposure to solar irradiance. The blue component of this light is known to influence the activity of the stress-inducible sigma factor Sigma B (σB). In this study, the influence of temperature and growth phase on the response of L. monocytogenes to blue light was investigated and the global transcriptional response to blue light was elucidated using an RNAseq-based approach. Stationary phase cells were found to be significantly more resistant to killing by blue light (470 nm) than exponential phase cells. Temperature also had a marked effect on blue light resistance with cells cultured at 37°C being much more sensitive than cells grown at 30°C. The role of σB in light tolerance was confirmed but this effect was observed only at 30°C. σB activation by blue light was assessed by measuring the transcriptional response of known σB-dependent genes (sigB, lmo2230, and opuCA) to light. The transcripts were induced by blue light only at 30°C suggesting that blue light fails to activate σB at 37°C. The light-induced transcription at 30°C was dependent on a functional blue light sensor, Lmo0799 (which we rename herein as RsbL). A transcriptomic analysis of the response to sub-lethal levels of blue light found that the changes in transcription were almost entirely σB-dependent. A mutant where the light sensing mechanism of RsbL was inactivated through an amino acid substitution (Cys56Ala) was found to have an attenuated response to blue light, but residual activation of σB-dependent genes suggested that alternative routes for activation of σB by light are likely to exist. Overall, the study highlights the central role of σB in the response of this pathogen to visible light and further shows that light sensing is absent at temperatures that exist within the mammalian host.
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Affiliation(s)
- Amber L Dorey
- Microbiology, School of Natural Sciences, Bacterial Stress Response Group, National University of Ireland Galway, Galway, Ireland
| | | | | | - Conor P O'Byrne
- Microbiology, School of Natural Sciences, Bacterial Stress Response Group, National University of Ireland Galway, Galway, Ireland
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Violet-Blue Light Arrays at 405 Nanometers Exert Enhanced Antimicrobial Activity for Photodisinfection of Monomicrobial Nosocomial Biofilms. Appl Environ Microbiol 2019; 85:AEM.01346-19. [PMID: 31444205 PMCID: PMC6803304 DOI: 10.1128/aem.01346-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/16/2019] [Indexed: 12/13/2022] Open
Abstract
This study reports the efficacy of VBL and blue light (BL) and their antimicrobial activity against mature biofilms of a range of important nosocomial pathogens. While this study investigated the antibacterial activity of a range of wavelengths of between 375 and 450 nm and identified a specific wavelength region (∼405 nm) with increased antibacterial activity, decontamination was dependent on the bacterial species, strain, irradiation parameters, and experimental conditions. Further research with controlled experiments that ameliorate the heating effects and improve the optical properties are required to optimize the dosing parameters to advance the successful clinical translation of this technology. Light-emitting diodes (LEDs) demonstrate therapeutic effects for a range of biomedical applications, including photodisinfection. Bands of specific wavelengths (centered at 405 nm) are reported to be the most antimicrobial; however, there remains no consensus on the most effective irradiation parameters for optimal photodisinfection. The aim of this study was to assess decontamination efficiency by direct photodisinfection of monomicrobial biofilms using a violet-blue light (VBL) single-wavelength array (SWA) and multiwavelength array (MWA). Mature biofilms of nosocomial bacteria (Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus) were grown on 96-well polypropylene PCR plates. The biofilms were then exposed to VBL for 2,700 s (SWA) and 1,170 s (MWA) to deliver 0 to 670 J/cm2, and the antibacterial activity of VBL was assessed by comparing the seeding of the irradiated and the nonirradiated biofilms. Nonirradiated groups were used as controls. The VBL arrays were characterized optically (spectral irradiance and beam profile) and thermally. The SWA delivered 401-nm VBL and the MWA delivered between 379-nm and 452-nm VBL, albeit at different irradiances and with different beam profiles. In both arrays, the irradiated groups were exposed to increased temperatures compared to the nonirradiated controls. All bacterial isolates were susceptible to VBL and demonstrated reductions in the seeding of exposed biofilms compared with the nonirradiated controls. VBL at 405 nm exerted the most antimicrobial activity, exhibiting reductions in seeding of up to 94%. Decontamination efficiency is dependent on the irradiation parameters, bacterial species and strain, and experimental conditions. Controlled experiments that ameliorate the heating effects and improve the optical properties are required to optimize the dosing parameters to advance the successful clinical translation of this technology. IMPORTANCE This study reports the efficacy of VBL and blue light (BL) and their antimicrobial activity against mature biofilms of a range of important nosocomial pathogens. While this study investigated the antibacterial activity of a range of wavelengths of between 375 and 450 nm and identified a specific wavelength region (∼405 nm) with increased antibacterial activity, decontamination was dependent on the bacterial species, strain, irradiation parameters, and experimental conditions. Further research with controlled experiments that ameliorate the heating effects and improve the optical properties are required to optimize the dosing parameters to advance the successful clinical translation of this technology.
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35
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Hyun JE, Lee SY. Antibacterial effect and mechanisms of action of 460-470 nm light-emitting diode against Listeria monocytogenes and Pseudomonas fluorescens on the surface of packaged sliced cheese. Food Microbiol 2019; 86:103314. [PMID: 31703869 DOI: 10.1016/j.fm.2019.103314] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 07/10/2019] [Accepted: 08/24/2019] [Indexed: 01/01/2023]
Abstract
The aim of this study was to investigate the antibacterial effect of 460-470 nm light-emitting diode (LED460-470nm) illumination against pathogens and spoilage bacteria on the surface of agar media and packaged sliced cheese. LED460-470nm illumination highly inhibited the growth of Listeria monocytogenes and Pseudomonas fluorescens on agar media covered with oriented polypropylene (OPP) film (thickness, 0.03 mm). When sliced cheeses inoculated with L. monocytogenes or P. fluorescens and packaged with OPP film were illuminated by an LED460-470 nm at 4 or 25 °C, reduction levels of L. monocytogenes and P. fluorescens on packaged slice cheese were higher at 4 °C than at 25 °C. There were no significant differences in color between non-illuminated and illuminated sliced cheese after storage for 7 d at 4 °C. LED460-470 nm illumination at 4 °C for 4 d caused cellular injury of L. monocytogenes and P. fluorescens related to RNA, protein, and peptidoglycan metabolism, and a disruption of the cell membrane and loss of cytoplasmic components were observed from TEM results. These results suggest that LED460-470 nm illumination, in combination with refrigeration temperatures, may be applied to extend the shelf-life of packaged slice cheese and minimize the risk of foodborne disease, without causing color deterioration.
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Affiliation(s)
- Jeong-Eun Hyun
- Department of Food and Nutrition, Chung-Ang University, 4726, Seodong-daero, Anseong-si, Gyeonggi-do, Republic of Korea
| | - Sun-Young Lee
- Department of Food and Nutrition, Chung-Ang University, 4726, Seodong-daero, Anseong-si, Gyeonggi-do, Republic of Korea.
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36
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Kang S, Meng Y, Cheng X, Tu J, Guo D, Xu Y, Liang S, Xia X, Shi C. Effects of 405-nm LED Treatment on the Resistance of Listeria monocytogenes to Subsequent Environmental Stresses. Front Microbiol 2019; 10:1907. [PMID: 31474971 PMCID: PMC6706791 DOI: 10.3389/fmicb.2019.01907] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 08/05/2019] [Indexed: 11/13/2022] Open
Abstract
Listeria monocytogenes can persist under a wide range of stress conditions, contributing to its ubiquitous distribution and unique pathogenic traits. Light from light-emitting diodes (LEDs) has recently been shown to inactivate various pathogens. Thus, the aim of the present study was to evaluate the effects of light treatment using a 405-nm LED on the subsequent resistance of L. monocytogenes to environmental stresses, including oxidative stress, ultraviolet (UV) irradiation, low temperature, osmotic pressure, simulated gastric fluid (SGF), and bile salts. Following 405-nm LED illumination at 4°C for 150 min, the survival of L. monocytogenes was examined after exposure to oxidative stress (0.04% H2O2), UV irradiation (253.7 nm), low temperature (4°C), osmotic pressure (10, 15, or 20% NaCl), SGF (pH 2.5), or bile salts (2%). The mechanisms responsible for changes in stress tolerance were identified by assessing the transcriptional responses and membrane integrity of L. monocytogenes. The 405-nm LED treatment reduced the resistance of L. monocytogenes to all the stresses tested. Reverse transcription quantitative real-time polymerase chain reaction analysis indicated that the transcription of multiple genes associated with stress resistance, including betL, gbuA, oppA, fri, bsh, and arcA, was reduced by 405-nm LED. Confocal laser scanning microscopy revealed that 405-nm LED treatment disrupted the integrity of the L. monocytogenes cell membrane compared with untreated bacteria. Therefore, 405-nm LED illumination appears to reduce the resistance of L. monocytogenes to various stress conditions. These findings suggest that 405-nm LED treatment could be used to effectively prevent and/or control with L. monocytogenes contamination along the entire food-processing chain, from production to consumption.
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Affiliation(s)
- Shenmin Kang
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yujie Meng
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xiaomeng Cheng
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Junhong Tu
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Du Guo
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yunfeng Xu
- College of Food and Bioengineering, Henan University of Science and Technology, Luoyang, China
| | - Sen Liang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, Beijing, China
| | - Xiaodong Xia
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Chao Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
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37
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Thurman CE, Muthuswamy A, Klinger MM, Roble GS. Safety Evaluation of a 405-nm LED Device for Direct Antimicrobial Treatment of the Murine Brain. Comp Med 2019; 69:283-290. [PMID: 31387666 PMCID: PMC6733165 DOI: 10.30802/aalas-cm-18-000126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/23/2018] [Accepted: 04/04/2019] [Indexed: 11/05/2022]
Abstract
Antimicrobial resistance is a growing problem in human medicine that extends to biomedical research. Compared with chemical-based therapies, light-based therapies present an alternative to traditional pharmaceuticals and are less vulnerable to acquired bacterial resistance. Due to immunologic privilege and relative tissue sensitivity to topical antibiotics, the brain poses a unique set of difficulties with regard to antimicrobial therapy. This study focused on 405-nm 'true violet' light-which has been shown to kill multiple clinically relevant bacterial species in vitro yet leave mammalian cells unscathed-and its effect on the murine brain. We built a 405-nm LED array, validated its power and efficacy against a clinical bacterial isolate in vitro, and then, at the time of craniotomy, treated mice with various doses of 405-nm light (36, 45, and 54 J/cm²). The selected doses caused no behavioral derangements postoperatively or any observable brain pathology as determined postmortem by histologic evaluation and immunofluorescence staining for caspase 3 and glial fibrillary acidic protein, markers of apoptosis and necrosis. True-violet light devices may present an inexpensive refinement to current practices for maintaining open craniotomy sites or reducing bacterial loads in contaminated surgical sites.
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Affiliation(s)
- Colleen E Thurman
- NYU–Regeneron Postdoctoral Training Program in Laboratory Animal Medicine, New York, New York
- Office of Veterinary Resources, New York University, New York, New York
- Regeneron Pharmaceuticals, Tarrytown, New York; and
| | - Anantharaman Muthuswamy
- NYU–Regeneron Postdoctoral Training Program in Laboratory Animal Medicine, New York, New York
- Regeneron Pharmaceuticals, Tarrytown, New York; and
| | - Mark M Klinger
- NYU–Regeneron Postdoctoral Training Program in Laboratory Animal Medicine, New York, New York
- Office of Veterinary Resources, New York University, New York, New York
| | - Gordon S Roble
- NYU–Regeneron Postdoctoral Training Program in Laboratory Animal Medicine, New York, New York
- Office of Veterinary Resources, New York University, New York, New York
- Department of Comparative Medicine, Fred Hutchinson Cancer Research Center, Seattle, Washington
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38
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Mycobacterium tuberculosis. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2019; 61:100-115. [PMID: 29356839 DOI: 10.1007/s00103-017-2660-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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39
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Cabral J, Ag R. Blue Light Disinfection in Hospital Infection Control: Advantages, Drawbacks, and Pitfalls. Antibiotics (Basel) 2019; 8:antibiotics8020058. [PMID: 31067733 PMCID: PMC6627448 DOI: 10.3390/antibiotics8020058] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/27/2019] [Accepted: 05/02/2019] [Indexed: 01/09/2023] Open
Abstract
Hospital acquired infections (HAIs) are a serious problem that potentially affects millions of patients whenever in contact with hospital settings. Worsening the panorama is the emergence of antimicrobial resistance by most microorganisms implicated in HAIs. Therefore, the improvement of the actual surveillance methods and the discovery of alternative approaches with novel modes of action is vital to overcome the threats created by the emergence of such resistances. Light therapy modalities represent a viable and effective alternative to the conventional antimicrobial treatment and can be preponderant in the control of HAIs, even against multidrug resistant organisms (MDROs). This review will initially focus on the actual state of HAIs and MDROs and which methods are currently available to fight them, which is followed by the exploration of antimicrobial photodynamic therapy (aPDT) and antimicrobial blue light therapy (aBLT) as alternative approaches to control microorganisms involved in HAIs. The advantages and drawbacks of BLT relatively to aPDT and conventional antimicrobial drugs as well as its potential applications to destroy microorganisms in the healthcare setting will also be discussed.
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Affiliation(s)
- João Cabral
- Division of Microbiology, Department of Pathology, Porto Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal.
| | - Rodrigues Ag
- Division of Microbiology, Department of Pathology, Porto Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal.
- CINTESIS-Center for Health Technology and Services Research, 4200-450 Porto, Portugal.
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40
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Stratford JP, Edwards CLA, Ghanshyam MJ, Malyshev D, Delise MA, Hayashi Y, Asally M. Electrically induced bacterial membrane-potential dynamics correspond to cellular proliferation capacity. Proc Natl Acad Sci U S A 2019; 116:9552-9557. [PMID: 31000597 PMCID: PMC6511025 DOI: 10.1073/pnas.1901788116] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Membrane-potential dynamics mediate bacterial electrical signaling at both intra- and intercellular levels. Membrane potential is also central to cellular proliferation. It is unclear whether the cellular response to external electrical stimuli is influenced by the cellular proliferative capacity. A new strategy enabling electrical stimulation of bacteria with simultaneous monitoring of single-cell membrane-potential dynamics would allow bridging this knowledge gap and further extend electrophysiological studies into the field of microbiology. Here we report that an identical electrical stimulus can cause opposite polarization dynamics depending on cellular proliferation capacity. This was demonstrated using two model organisms, namely Bacillus subtilis and Escherichia coli, and by developing an apparatus enabling exogenous electrical stimulation and single-cell time-lapse microscopy. Using this bespoke apparatus, we show that a 2.5-second electrical stimulation causes hyperpolarization in unperturbed cells. Measurements of intracellular K+ and the deletion of the K+ channel suggested that the hyperpolarization response is caused by the K+ efflux through the channel. When cells are preexposed to 400 ± 8 nm wavelength light, the same electrical stimulation depolarizes cells instead of causing hyperpolarization. A mathematical model extended from the FitzHugh-Nagumo neuron model suggested that the opposite response dynamics are due to the shift in resting membrane potential. As predicted by the model, electrical stimulation only induced depolarization when cells are treated with antibiotics, protonophore, or alcohol. Therefore, electrically induced membrane-potential dynamics offer a reliable approach for rapid detection of proliferative bacteria and determination of their sensitivity to antimicrobial agents at the single-cell level.
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Affiliation(s)
- James P Stratford
- School of Life Sciences, University of Warwick, Coventry, West Midlands, CV4 7AL, United Kingdom
- Warwick Integrative Synthetic Biology Centre, University of Warwick, Coventry, West Midlands, CV4 7AL,United Kingdom
| | - Conor L A Edwards
- School of Life Sciences, University of Warwick, Coventry, West Midlands, CV4 7AL, United Kingdom
| | - Manjari J Ghanshyam
- School of Life Sciences, University of Warwick, Coventry, West Midlands, CV4 7AL, United Kingdom
| | - Dmitry Malyshev
- School of Life Sciences, University of Warwick, Coventry, West Midlands, CV4 7AL, United Kingdom
| | - Marco A Delise
- School of Life Sciences, University of Warwick, Coventry, West Midlands, CV4 7AL, United Kingdom
| | - Yoshikatsu Hayashi
- Department of Biomedical Engineering, School of Biological Sciences, University of Reading, Reading, Berkshire, RG6 6AH, United Kingdom
| | - Munehiro Asally
- School of Life Sciences, University of Warwick, Coventry, West Midlands, CV4 7AL, United Kingdom;
- Warwick Integrative Synthetic Biology Centre, University of Warwick, Coventry, West Midlands, CV4 7AL,United Kingdom
- Bio-Electrical Engineering Innovation Hub, University of Warwick, Coventry, West Midlands, CV4 7AL, United Kingdom
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Hamblin MR, Abrahamse H. Can light-based approaches overcome antimicrobial resistance? Drug Dev Res 2019; 80:48-67. [PMID: 30070718 PMCID: PMC6359990 DOI: 10.1002/ddr.21453] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/06/2018] [Accepted: 07/07/2018] [Indexed: 01/10/2023]
Abstract
The relentless rise of antibiotic resistance is considered one of the most serious problems facing mankind. This mini-review will cover three cutting-edge approaches that use light-based techniques to kill antibiotic-resistant microbial species, and treat localized infections. First, we will discuss antimicrobial photodynamic inactivation using rationally designed photosensitizes combined with visible light, with the added possibility of strong potentiation by inorganic salts such as potassium iodide. Second, the use of blue and violet light alone that activates endogenous photoactive porphyrins within the microbial cells. Third, it is used for "safe UVC" at wavelengths between 200 nm and 230 nm that can kill microbial cells without damaging host mammalian cells. We have gained evidence that all these approaches can kill multidrug resistant bacteria in vitro, and they do not induce themselves any resistance, and moreover can treat animal models of localized infections caused by resistant species that can be monitored by noninvasive bioluminescence imaging. Light-based antimicrobial approaches are becoming a growing translational part of anti-infective treatments in the current age of resistance.
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Affiliation(s)
- Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts
| | - Heidi Abrahamse
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, South Africa
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Ghate VS, Zhou W, Yuk HG. Perspectives and Trends in the Application of Photodynamic Inactivation for Microbiological Food Safety. Compr Rev Food Sci Food Saf 2019; 18:402-424. [DOI: 10.1111/1541-4337.12418] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 12/20/2022]
Affiliation(s)
- Vinayak S. Ghate
- Food Science & Technology Programme, Dept. of Chemistry; Natl. Univ. of Singapore; Science Drive 2 117543 Singapore
| | - Weibiao Zhou
- Food Science & Technology Programme, Dept. of Chemistry; Natl. Univ. of Singapore; Science Drive 2 117543 Singapore
| | - Hyun-Gyun Yuk
- Dept. of Food Science and Technology; Korea National Univ. of Transportation; 61 Daehak-ro Jeungpyeong-gun Chungbuk 27909 Republic of Korea
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43
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Aurum FS, Nguyen LT. Efficacy of photoactivated curcumin to decontaminate food surfaces under blue light emitting diode. J FOOD PROCESS ENG 2019. [DOI: 10.1111/jfpe.12988] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Fawzan Sigma Aurum
- Assessment Institute for Agricultural Technology of Bali, Indonesian Agency for Agricultural Research and Development (IAARD), Ministry of Agriculture Jakarta Indonesia
- Department of Food, Agriculture and Bioresources, Asian Institute of Technology (AIT) Pathum Thani Thailand
| | - Loc Thai Nguyen
- Department of Food, Agriculture and Bioresources, Asian Institute of Technology (AIT) Pathum Thani Thailand
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Grangeteau C, Lepinois F, Winckler P, Perrier-Cornet JM, Dupont S, Beney L. Cell Death Mechanisms Induced by Photo-Oxidation Studied at the Cell Scale in the Yeast Saccharomyces cerevisiae. Front Microbiol 2018; 9:2640. [PMID: 30455675 PMCID: PMC6230929 DOI: 10.3389/fmicb.2018.02640] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 10/16/2018] [Indexed: 12/22/2022] Open
Abstract
Blue light (400–430 nm) is known to induce lethal effects in some species of fungi by photo-oxidation caused by the excitation of porphyrins but the mechanisms involved remain poorly understood. In this work, we exposed the yeast Saccharomyces cerevisiae to a high density light flux with two-photon excitation (830 nm equivalent to a one-photon excitation around 415 nm) and used quasi real-time visualization with confocal microscopy to study the initiation and dynamics of photo-oxidation in subcellular structures. Our results show that the oxidation generated by light treatments led to the permeabilization of the plasma membrane accompanied by the sudden expulsion of the cellular content, corresponding to cell death by necrosis. Moreover, excitation in the plasma membrane led to very fast oxidation and membrane permeabilization (<60 s) while excitation at the center of the cell did not induce permeabilization even after a period exceeding 600 s. Finally, our study shows that the relationship between the laser power used for two-photon excitation and the time required to permeabilize the plasma membrane was not linear. Thus, the higher the power used, the lower the energy required to permeabilize the plasma membrane. We conclude that fungal destruction can be generated very quickly using a high density light flux. Better knowledge of the intracellular processes and the conditions necessary to induce necrosis should make it possible in the future to improve the efficiency of antimicrobial strategies photo-oxidation-based.
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Affiliation(s)
- Cédric Grangeteau
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, France
| | - Florine Lepinois
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, France
| | - Pascale Winckler
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, France
| | | | - Sebastien Dupont
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, France
| | - Laurent Beney
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, France
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Tran VN, Dasagrandhi C, Truong VG, Kim YM, Kang HW. Antibacterial activity of Staphylococcus aureus biofilm under combined exposure of glutaraldehyde, near-infrared light, and 405-nm laser. PLoS One 2018; 13:e0202821. [PMID: 30148865 PMCID: PMC6110465 DOI: 10.1371/journal.pone.0202821] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 08/09/2018] [Indexed: 01/31/2023] Open
Abstract
Healthcare-associated infections have increasingly become problematic in the endoscopic procedures resulting in several severe diseases such as carbapenem-resistant Enterobacteriaceae (CRE)-related infections, pneumonia, and bacteremia. Especially, some bacterial strains are resistant to traditional antimicrobials. Therefore, the necessity of developing new antibiotics or management to deal with bacterial infections has been increasing. The current study combined a low concentration of glutaraldehyde (GTA) with near-infrared (NIR) light and 405-nm laser to entail antibacterial activity on Staphylococcus aureus biofilm. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and colony forming unit (CFU) counting were used to quantify the viable cells while fluorescent and scanning electron microscopic images were used to qualitatively evaluate the cell membrane integrity and structural deformation, respectively. Practically, S. aureus biofilm was highly susceptible (7% cell viability and 6.8-log CFU/cm2 bacterial reduction for MTT assay and CFU analysis, respectively) to the combination of GTA (0.1%), NIR light (270 J/cm2), and 405-nm laser (288 J/cm2) exposure. GTA could form either DNA-protein or protein-protein crosslinks to inhibit DNA and protein synthesis. The NIR light induced the thermal damage on protein/enzymes while 405-nm laser could induce reactive oxygen species (ROS) to damage the bacterial membrane. Thus, the proposed technique may be a feasible modality for endoscope cleaning to prevent any secondary infection in the healthcare industry.
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Affiliation(s)
- Van Nam Tran
- Department of Biomedical Engineering, Pukyong National University, Busan, Korea
| | | | - Van Gia Truong
- Department of Biomedical Engineering, Pukyong National University, Busan, Korea
| | - Young-Mog Kim
- Department of Food Science and Technology, Pukyong National University, Busan, Korea
| | - Hyun Wook Kang
- Department of Biomedical Engineering, Pukyong National University, Busan, Korea
- Center for Marine-Integrated Biomedical Technology, Pukyong National University, Busan, Korea
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46
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Ma J, Hiratsuka T, Etoh T, Akada J, Fujishima H, Shiraishi N, Yamaoka Y, Inomata M. Anti-proliferation effect of blue light-emitting diodes against antibiotic-resistant Helicobacter pylori. J Gastroenterol Hepatol 2018; 33:1492-1499. [PMID: 29218793 DOI: 10.1111/jgh.14066] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 11/13/2017] [Accepted: 11/29/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIM Infection by Helicobacter pylori is implicated in a wide range of upper gastrointestinal diseases. Owing to the rapid emergence of antibiotic-resistant strains of H. pylori, the development of novel treatment modalities for antibiotic-resistant H. pylori infection is a key priority. Blue light-emitting diodes (LED) may represent a unique option owing to their antimicrobial effect. In this study, we aimed to evaluate the anti-proliferative effect of blue LED against antibiotic-resistant H. pylori. METHODS Ten antibiotic-resistant strains and one sensitive H. pylori strain were used in this study. After irradiation by blue LED along time course, the viability of H. pylori was evaluated by enumerating colony forming units. Morphological changes in H. pylori were observed using a scanning electron microscope. Reductase activity was measured as an indicator of bacterial cellular activity. Total reactive oxygen species was monitored using fluorescence intensity and fluorescence microscope imaging. RESULTS After irradiation by blue LED, the numbers of H. pylori in all the strains were significantly reduced compared with control group. The H. pylori exhibited a short rod-shaped morphology after irradiation; no such change was observed in H. pylori not exposed to blue LED. Re-irradiation of surviving strain after the initial irradiation also exhibited the same anti-proliferation effect. After blue LED irradiation, bacterial cellular activity was lower, and total reactive oxygen species production was significantly higher in blue LED group, compared with that in control. CONCLUSIONS Blue LED could be a new treatment to eradicate infection with antibiotic-resistant H. pylori.
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Affiliation(s)
- Jianwei Ma
- Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine, Oita, Japan.,Department of General Surgery, The First Hospital of Hebei Medical University, Hebei, China
| | - Takahiro Hiratsuka
- Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine, Oita, Japan
| | - Tsuyoshi Etoh
- Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine, Oita, Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Oita, Japan
| | - Hajime Fujishima
- Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine, Oita, Japan
| | - Norio Shiraishi
- Comprehensive Surgery for Community Medicine, Oita University Faculty of Medicine, Oita, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Oita, Japan
| | - Masafumi Inomata
- Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine, Oita, Japan
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47
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Li X, Kim MJ, Yuk HG. Influence of 405 nm light-emitting diode illumination on the inactivation of Listeria monocytogenes and Salmonella spp. on ready-to-eat fresh salmon surface at chilling storage for 8 h and their susceptibility to simulated gastric fluid. Food Control 2018. [DOI: 10.1016/j.foodcont.2018.01.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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48
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Josewin SW, Kim MJ, Yuk HG. Inactivation of Listeria monocytogenes and Salmonella spp. on cantaloupe rinds by blue light emitting diodes (LEDs). Food Microbiol 2018; 76:219-225. [PMID: 30166145 DOI: 10.1016/j.fm.2018.05.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 05/24/2018] [Accepted: 05/26/2018] [Indexed: 01/01/2023]
Abstract
This study evaluated the potential of blue light-emitting diodes (LED) of wavelength 405 and 460 nm in combination with sodium chlorophyllin to inactivate Listeria monocytogenes and Salmonella spp. on cantaloupe rind. A cocktail culture of L. monocytogenes or Salmonella spp. strains was surface inoculated onto cantaloupe rinds to reach a final concentration of 4 log CFU/cm2 and dip-treated in a 100 μM sodium copper chlorophyllin solution. The cantaloupe samples were then exposed to 405 or 460 nm LEDs at a total dose of 1210 J/cm2 and 5356 J/cm2, respectively, at 4 and 20 °C. Results showed that the antibacterial efficacy against both pathogens on cantaloupe rinds between LED alone and LED with the chlorophyllin were statistically similar with bacterial inactivation ranging from 1.1 to 3 log CFU/cm2 in most of the cases or the difference was only minimal. A similar inactivation of 3 log CFU/cm2 was obtained in the case of L. monocytogenes and Salmonella spp. when illuminated by 405 nm LEDs while the inactivation of L. monocytogenes was higher than Salmonella spp. when illuminated by 460 nm LED. The δ value, a modified Weibull model parameter defined as the time (h) taken to reduce the bacterial population by 90%, was computed to compare the inactivation rates of the conditions. It was inferred that illumination with 405 nm LED required a lower δ value than 460 nm LED illumination (P < 0.05) for the inactivation of L. monocytogenes at 20 °C and Salmonella spp. at 4 °C. Thus the findings of this study indicate a promising application of blue LEDs to inactivate these pathogens on the surface of cantaloupe, minimizing the risk of listeriosis and salmonellosis by consumption of cantaloupe.
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Affiliation(s)
- Sherrill Wesley Josewin
- Food Science & Technology Programme, Department of Chemistry, National University of Singapore, Science Drive 4, 117543, Singapore
| | - Min-Jeong Kim
- Research Group of Consumer Safety, Research Division of Strategic Food Technology, Korea Food Research Institute, 245, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, Jeollabuk-do, 55365, Republic of Korea
| | - Hyun-Gyun Yuk
- Department of Food Science and Technology, Korea National University of Transportation, 61 Daehak-ro, Jeungpyeong-gun, Chungbuk, 27909, Republic of Korea.
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49
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Plavskii VY, Mikulich AV, Tretyakova AI, Leusenka IA, Plavskaya LG, Kazyuchits OA, Dobysh II, Krasnenkova TP. Porphyrins and flavins as endogenous acceptors of optical radiation of blue spectral region determining photoinactivation of microbial cells. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 183:172-183. [PMID: 29715591 DOI: 10.1016/j.jphotobiol.2018.04.021] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/19/2018] [Accepted: 04/14/2018] [Indexed: 12/23/2022]
Abstract
It is shown that exposure of suspensions of gram-positive Staphylococcus aureus, gram-negative Escherichia coli and yeast-like fungi Candida albicans to laser radiation of blue spectral region with 405 and 445 nm causes their growth inhibition without prior addition of exogenous photosensitizers. It is experimentally confirmed that compounds of flavin type capable of sensitizing the formation of reactive oxygen species can act as acceptors of optical radiation of blue spectral region determining its antimicrobial effect along with endogenous metal-free porphyrins (the role of endogenous porphyrins has been confirmed earlier by a number of researchers). The participation of these compounds in the antimicrobial effect of laser radiation is supported by the registration of porphyrin and flavin fluorescence in extracts of microbial cells upon excitation by radiation used to inactivate the pathogens. In addition, the intensity of the porphyrin fluorescence in extracts of microbial cells in the transition from radiation with λ = 405 nm to radiation with λ = 445 nm decreases by 15-30 times, whereas the photosensitivity of the cells under study in this transition decreases only 3.7-6.2 times. The contribution of porphyrin photosensitizers is most pronounced upon exposure to radiation with λ = 405 nm (absorption maximum of the Soret band of porphyrins), and flavins - upon exposure to radiation with λ = 445 nm (maximum in the flavin absorption spectrum and minimum in the absorption spectrum of porphyrins). The ratio between the intensity of the porphyrin and flavin components in the fluorescence spectrum of extracts depends on the type of microbial cells.
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Affiliation(s)
- V Yu Plavskii
- State Scientific Institution B.I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 220072 Minsk, 68-2 Nezavisimosti ave., Belarus.
| | - A V Mikulich
- State Scientific Institution B.I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 220072 Minsk, 68-2 Nezavisimosti ave., Belarus
| | - A I Tretyakova
- State Scientific Institution B.I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 220072 Minsk, 68-2 Nezavisimosti ave., Belarus
| | - I A Leusenka
- State Scientific Institution B.I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 220072 Minsk, 68-2 Nezavisimosti ave., Belarus
| | - L G Plavskaya
- State Scientific Institution B.I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 220072 Minsk, 68-2 Nezavisimosti ave., Belarus
| | - O A Kazyuchits
- Republican Manufacturing Unitary Enterprise Academpharm, 220141 Minsk, Kuprevich st. 5/3, Belarus
| | - I I Dobysh
- Republican Manufacturing Unitary Enterprise Academpharm, 220141 Minsk, Kuprevich st. 5/3, Belarus
| | - T P Krasnenkova
- Republican Manufacturing Unitary Enterprise Academpharm, 220141 Minsk, Kuprevich st. 5/3, Belarus
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50
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Tomb RM, White TA, Coia JE, Anderson JG, MacGregor SJ, Maclean M. Review of the Comparative Susceptibility of Microbial Species to Photoinactivation Using 380-480 nm Violet-Blue Light. Photochem Photobiol 2018; 94:445-458. [DOI: 10.1111/php.12883] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 12/08/2017] [Indexed: 12/24/2022]
Affiliation(s)
- Rachael M. Tomb
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST); Department of Electronic & Electrical Engineering; University of Strathclyde; Glasgow UK
| | - Tracy A. White
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST); Department of Electronic & Electrical Engineering; University of Strathclyde; Glasgow UK
| | - John E. Coia
- Department of Clinical Microbiology; Glasgow Royal Infirmary; Glasgow UK
| | - John G. Anderson
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST); Department of Electronic & Electrical Engineering; University of Strathclyde; Glasgow UK
| | - Scott J. MacGregor
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST); Department of Electronic & Electrical Engineering; University of Strathclyde; Glasgow UK
| | - Michelle Maclean
- The Robertson Trust Laboratory for Electronic Sterilisation Technologies (ROLEST); Department of Electronic & Electrical Engineering; University of Strathclyde; Glasgow UK
- Department of Biomedical Engineering; University of Strathclyde; Glasgow UK
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