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Amoon H, Moghadam A, Hajkarim MC. Synthesis, characterization, and investigation of antibacterial activity of Novel CMC/CuO NPs/CQDs bionanocomposite coating. Int J Biol Macromol 2024; 268:131922. [PMID: 38688345 DOI: 10.1016/j.ijbiomac.2024.131922] [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: 12/17/2023] [Revised: 04/21/2024] [Accepted: 04/25/2024] [Indexed: 05/02/2024]
Abstract
In recent decades, healthcare-associated infections (HAIs) have become a common problem in healthcare facilities such as hospitals. As a result, researchers are currently developing nanocomposite coatings that are strengthened with antibacterial nanoparticles. In this research, a novel antibacterial bionanocomposite coating based on carboxymethyl cellulose polymer/copper oxide nanoparticles/carbon quantum dots was coated on medical grade 316 stainless steel by sol-gel dip-coating method. The effect of the concentration of nanocomposite components was investigated at four different levels to determine the best ratio with the most antibacterial activity. Structural characteristics of nanocomposite and coating were investigated using different analysis methods. The coating analysis showed that reinforcements are uniformly distributed in the polymer matrix. Antibacterial test of disc diffusion was performed by the Kirby-Bauer method and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) antibacterial test. The results showed that bionanocomposite was effective in the MIC assays against Staphylococcus aureus and Escherichia coli with MIC values of 25 mg/ml and >50 mg/ml, respectively. The inhibition zones for E. coli and S. aureus were 17 and 32 mm, respectively, at 10 μg/disc of gentamicin. SEM images displayed significant and evident alterations in the structure of bacterial morphology, indicating cellular damage.
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Affiliation(s)
- Hamidreza Amoon
- Department of Materials Science and Engineering, Razi University, Kermanshah, Iran
| | - Ayoub Moghadam
- Department of Materials Science and Engineering, Razi University, Kermanshah, Iran.
| | - Maryam Chalabi Hajkarim
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Zhang X, Zhu Z, Liu W, Gao F, Guo J, Song B, Lee LP, Zhang F. The Selective Function of Quantum Biological Electron Transfer between DNA Bases and Metal Ions in DNA Replication. J Phys Chem Lett 2022; 13:7779-7787. [PMID: 35969805 DOI: 10.1021/acs.jpclett.2c01877] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Metal ions play vital roles in the electron transfer between biological molecules in humans, animals, and plants. However, the electron transfer between metal ions and nucleic acids and its impact on DNA-ion binding during DNA replication has been ignored. Here, we present a long-range quantum biological electron transfer (QBET) between DNA bases and metal ions and its selective function of DNA-ion binding in DNA replication. We discover biophysical DNA-ion binding and create biological filters that allow selective DNA replication by dual modulators of the valence and concentration of metal ions. QBET-based DNA replication filters provide powerful tools for ultrasensitive polymerase chain reaction (PCR) to selectively amplify target sequences with a discrete concentration window of metal ions; for example, Au3+ exhibits a concentration window that is approximately 3 orders of magnitude lower than that of Na+. DNA-ion filters provide new perspectives into metal ion-mediated QBET in DNA replication and hold great potential in life sciences and medical applications.
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Affiliation(s)
- Xianjing Zhang
- Key Laboratory of Optical Technology and Instrument for Medicine, Ministry of Education, School of Optical-Electrical Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Zhi Zhu
- Key Laboratory of Optical Technology and Instrument for Medicine, Ministry of Education, School of Optical-Electrical Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Wenpeng Liu
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Feng Gao
- Key Laboratory of Optical Technology and Instrument for Medicine, Ministry of Education, School of Optical-Electrical Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Jun Guo
- Key Laboratory of Optical Technology and Instrument for Medicine, Ministry of Education, School of Optical-Electrical Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Bo Song
- Key Laboratory of Optical Technology and Instrument for Medicine, Ministry of Education, School of Optical-Electrical Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Luke P Lee
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
- Department of Bioengineering, Department of Electrical Engineering and Computer Science, University of California, Berkeley, California 94720, United States
- Institute of Quantum Biophysics, Department of Biophysics, Sungkyunkwan University, Suwon 16419, Korea
| | - Feng Zhang
- Key Laboratory of Optical Technology and Instrument for Medicine, Ministry of Education, School of Optical-Electrical Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325001, China
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Oral Disease, Stomatology Hospital, School of Biomedical Engineering, Guangzhou Medical University, Guangzhou 511436, China
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Ma X, Zhou S, Xu X, Du Q. Copper-containing nanoparticles: Mechanism of antimicrobial effect and application in dentistry-a narrative review. Front Surg 2022; 9:905892. [PMID: 35990090 PMCID: PMC9388913 DOI: 10.3389/fsurg.2022.905892] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 07/19/2022] [Indexed: 11/18/2022] Open
Abstract
Copper has been used as an antimicrobial agent long time ago. Nowadays, copper-containing nanoparticles (NPs) with antimicrobial properties have been widely used in all aspects of our daily life. Copper-containing NPs may also be incorporated or coated on the surface of dental materials to inhibit oral pathogenic microorganisms. This review aims to detail copper-containing NPs' antimicrobial mechanism, cytotoxic effect and their application in dentistry.
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Affiliation(s)
- Xinru Ma
- Department of Stomatology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Department of Stomatology, Hospital of Chengdu Office of People's Government of Tibetan Autonomous Region (West China Hospital Sichuan University Tibet Chengdu Branch Hospital), Chengdu, China
| | - Shiyu Zhou
- Department of Stomatology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiaoling Xu
- School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, China
| | - Qin Du
- Department of Stomatology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China
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Hyre A, Casanova-Hampton K, Subashchandrabose S. Copper Homeostatic Mechanisms and Their Role in the Virulence of Escherichia coli and Salmonella enterica. EcoSal Plus 2021; 9:eESP00142020. [PMID: 34125582 PMCID: PMC8669021 DOI: 10.1128/ecosalplus.esp-0014-2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Copper is an essential micronutrient that also exerts toxic effects at high concentrations. This review summarizes the current state of knowledge on copper handling and homeostasis systems in Escherichia coli and Salmonella enterica. We describe the mechanisms by which transcriptional regulators, efflux pumps, detoxification enzymes, metallochaperones, and ancillary copper response systems orchestrate cellular response to copper stress. E. coli and S. enterica are important pathogens of humans and animals. We discuss the critical role of copper during killing of these pathogens by macrophages and in nutritional immunity at the bacterial-pathogen-host interface. In closing, we identify opportunities to advance our understanding of the biological roles of copper in these model enteric bacterial pathogens.
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Affiliation(s)
- Amanda Hyre
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, NC
| | - Kaitlin Casanova-Hampton
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
| | - Sargurunathan Subashchandrabose
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX
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Soliman MY, Medema G, Bonilla BE, Brouns SJ, van Halem D. Inactivation of RNA and DNA viruses in water by copper and silver ions and their synergistic effect. WATER RESEARCH X 2020; 9:100077. [PMID: 33225254 PMCID: PMC7663217 DOI: 10.1016/j.wroa.2020.100077] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 10/19/2020] [Accepted: 11/01/2020] [Indexed: 05/19/2023]
Abstract
Cu and Ag have been used as bactericidal agents since ancient times, yet their antiviral capacity in water remains poorly understood. This study tested the effect of copper (Cu) and silver (Ag) on model RNA and DNA viruses MS2 and PhiX 174 in solution at pH 6-8. Cu caused MS2 inactivation with similar rates at pH 6 and 7 but was inert towards PhiX 174 regardless of pH. Ag inactivated both viruses, causing denaturation of MS2 and loss of capsid spikes in PhiX 174. Ag inactivation rates were pH dependent and increased with increasing pH. At pH 8, 6.5 logs of PhiX were inactivated after 3 h and 3 logs of MS2 after only 10 min. The combined use of Cu and Ag revealed synergy in disinfecting MS2 at pH ≥ 7. Although metal concentrations used were higher than the desired values for drinking water treatment, the results prove a promising potential of Cu and Ag combinations as efficient viricidal agents.
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Affiliation(s)
- Mona Y.M. Soliman
- Department of Water Management, Delft University of Technology, Stevinweg 1, 2628, CN Delft, the Netherlands
- Corresponding author.
| | - Gertjan Medema
- Department of Water Management, Delft University of Technology, Stevinweg 1, 2628, CN Delft, the Netherlands
- KWR Watercycle Research Institute, P.O. Box 1072, 3430 BB, Nieuwegein, the Netherlands
| | - Boris Estrada Bonilla
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
- Fagenbank, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
| | - Stan J.J. Brouns
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
- Fagenbank, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
| | - Doris van Halem
- Department of Water Management, Delft University of Technology, Stevinweg 1, 2628, CN Delft, the Netherlands
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Bugata LSP, Pitta Venkata P, Gundu AR, Mohammed Fazlur R, Reddy UA, Kumar JM, Mekala VR, Bojja S, Mahboob M. Acute and subacute oral toxicity of copper oxide nanoparticles in female albino Wistar rats. J Appl Toxicol 2019; 39:702-716. [PMID: 30618104 DOI: 10.1002/jat.3760] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 11/02/2018] [Accepted: 11/02/2018] [Indexed: 12/18/2022]
Abstract
The extensive use of copper oxide nanoparticles (CuO-NPs) in various industries and their wide range of applications have led to their accumulation in different ecological niches of the environment. This excess exposure raises the concern about its potential toxic effects on various organisms including humans. However, the hazardous potential of CuO-NPs in the literature is elusive, and it is essential to study its toxicity in different biological models. Hence, we have conducted single acute dose (2000 mg/kg) and multiple dose subacute (30, 300 and 1000 mg/kg daily for 28 days) oral toxicity studies of CuO-NPs in female albino Wistar rats following OECD guidelines 420 and 407 respectively. Blood analysis, tissue aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and acetylcholinesterase, superoxide dismutase, catalase, lipid malondialdehyde and reduced glutathione assays, and histopathology of the tissues were carried out. The higher dose treatments of the acute and subacute study caused significant alterations in biochemical and antioxidant parameters of the liver, kidney and brain tissues of the rat. In addition, histopathological evaluation of these three organs of treated rats showed significantly high abnormalities in their histoarchitecture when compared to control rats. We infer from the results that the toxicity observed in the liver, kidney and brain of treated rats could be due to the increased generation of reactive oxygen species by CuO-NPs.
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Affiliation(s)
- Lakshmi Sai Pratyusha Bugata
- Toxicology Unit, Applied Biology Division, CSIR-Indian Institute of Chemical, Technology, Hyderabad, Telangana, 500007, India
| | - Prabhakar Pitta Venkata
- Toxicology Unit, Applied Biology Division, CSIR-Indian Institute of Chemical, Technology, Hyderabad, Telangana, 500007, India
| | - Ananth Reddy Gundu
- Toxicology Unit, Applied Biology Division, CSIR-Indian Institute of Chemical, Technology, Hyderabad, Telangana, 500007, India
| | - Rahman Mohammed Fazlur
- Toxicology Unit, Applied Biology Division, CSIR-Indian Institute of Chemical, Technology, Hyderabad, Telangana, 500007, India
| | - Utkarsh A Reddy
- Toxicology Unit, Applied Biology Division, CSIR-Indian Institute of Chemical, Technology, Hyderabad, Telangana, 500007, India
| | - Jerald Mahesh Kumar
- CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad,, Telangana, 500007, India
| | | | - Sreedhar Bojja
- Analytical Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500007, India
| | - Mohammed Mahboob
- Toxicology Unit, Applied Biology Division, CSIR-Indian Institute of Chemical, Technology, Hyderabad, Telangana, 500007, India
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7
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Armstrong AM, Sobsey MD, Casanova LM. Disinfection of bacteriophage MS2 by copper in water. Appl Microbiol Biotechnol 2017; 101:6891-6897. [DOI: 10.1007/s00253-017-8419-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 11/28/2022]
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Armstrong AM, Sobsey MD, Casanova LM. Disinfection of Escherichia coli and Pseudomonas aeruginosa by copper in water. JOURNAL OF WATER AND HEALTH 2016; 14:424-432. [PMID: 27280608 DOI: 10.2166/wh.2016.059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
When households lack access to continuous piped water, water storage in the home creates opportunities for contamination. Storage in copper vessels has been shown to reduce microbes, but inactivation kinetics of enteric bacteria in water by copper alone needs to be understood. This work characterized inactivation kinetics of Escherichia coli and Pseudomonas aeruginosa by dissolved ionic copper in water. Reductions of E. coli and P. aeruginosa increase with increasing dose. At 0.3 mg/L, there was a 2.5 log10 reduction of E. coli within 6 hours. At 1 and 3 mg/L, the detection limit was reached between 3 and 6 hours; maximum reduction measured was 8.5 log10. For P. aeruginosa, at 6 hours there was 1 log10 reduction at 0.3 mg/L, 3.0 log10 at 1 mg/L, and 3.6 log10 at 3 mg/L. There was no significant decline in copper concentration. Copper inactivates bacteria under controlled conditions at doses between 0.3 and 1 mg/L. E. coli was inactivated more rapidly than P. aeruginosa. Copper at 1 mg/L can achieve 99.9% inactivation of P. aeruginosa and 99.9999997% inactivation of E. coli over 6 hours, making it a candidate treatment for stored household water.
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Affiliation(s)
- Andrew M Armstrong
- Water Missions International, 1150 Kinzer Street, Building 1605, N. Charleston, SC 29405-1484, USA
| | - Mark D Sobsey
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Lisa M Casanova
- Division of Environmental Health, School of Public Health, Georgia State University, 140 Decatur St, Atlanta, GA 30302, USA E-mail:
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MacDonald MC, Juran L, Jose J, Srinivasan S, Ali SI, Aronson KJ, Hall K. The impact of rainfall and seasonal variability on the removal of bacteria by a point-of-use drinking water treatment intervention in Chennai, India. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2015; 26:208-221. [PMID: 26405847 DOI: 10.1080/09603123.2015.1089532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Point-of-use water treatment has received widespread application in the developing world to help mitigate waterborne infectious disease. This study examines the efficacy of a combined filter and chemical disinfection technology in removing bacterial contaminants, and more specifically changes in its performance resulting from seasonal weather variability. During a 12-month field trial in Chennai, India, mean log-reductions were 1.51 for E. coli and 1.67 for total coliforms, and the highest concentration of indicator bacteria in treated water samples were found during the monsoon season. Analysis of variance revealed significant differences in the microbial load of indicator organisms (coliforms and E. coli) between seasons, storage time since treatment (TST), and samples with and without chlorine residuals. Findings indicate that the bacteriological quality of drinking water treated in the home is determined by a complex interaction of environmental and sociological conditions. Moreover, while the effect of disinfection was independent of season, the impact of storage TST on water quality was found to be seasonally dependent.
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Affiliation(s)
| | - Luke Juran
- b Department of Geography and Virginia Water Resources Research Center , Virginia Tech , Blacksburg , VA , USA
| | - Jincy Jose
- c Department of Civil Engineering , Indian Institute of Technology Madras , Chennai , India
| | - Sekar Srinivasan
- c Department of Civil Engineering , Indian Institute of Technology Madras , Chennai , India
| | - Syed I Ali
- a School of Engineering , University of Guelph , Guelph , Canada
| | - Kristan J Aronson
- d Department of Public Health Sciences , Queen's University , Kingston , ON , Canada
| | - Kevin Hall
- a School of Engineering , University of Guelph , Guelph , Canada
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Khan SJ, Reed RH, Rasul MG. Thin-film fixed-bed reactor for solar photocatalytic inactivation of Aeromonas hydrophila: influence of water quality. BMC Microbiol 2012. [PMID: 23194331 PMCID: PMC3556150 DOI: 10.1186/1471-2180-12-285] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Controlling fish disease is one of the major concerns in contemporary aquaculture. The use of antibiotics or chemical disinfection cannot provide a healthy aquaculture system without residual effects. Water quality is also important in determining the success or failure of fish production. Several solar photocatalytic reactors have been used to treat drinking water or waste water without leaving chemical residues. This study has investigated the impact of several key aspects of water quality on the inactivation of the pathogenic bacterium Aeromonas hydrophila using a pilot-scale thin-film fixed-bed reactor (TFFBR) system. RESULTS The level of inactivation of Aeromonas hydrophila ATCC 35654 was determined using a TFFBR with a photocatalytic area of 0.47 m(2) under the influence of various water quality variables (pH, conductivity, turbidity and colour) under high solar irradiance conditions (980-1100 W m(-2)), at a flow rate of 4.8 L h(-1) through the reactor. Bacterial enumeration were obtained through conventional plate count using trypticase soy agar media, cultured in conventional aerobic conditions to detect healthy cells and under ROS-neutralised conditions to detect both healthy and sub-lethally injured (oxygen-sensitive) cells. The results showed that turbidity has a major influence on solar photocatalytic inactivation of A. hydrophila. Humic acids appear to decrease TiO(2) effectiveness under full sunlight and reduce microbial inactivation. pH in the range 7-9 and salinity both have no major effect on the extent of photoinactivation or sub-lethal injury. CONCLUSIONS This study demonstrates the effectiveness of the TFFBR in the inactivation of Aeromonas hydrophila under the influence of several water quality variables at high solar irradiance, providing an opportunity for the application of solar photocatalysis in aquaculture systems, as long as turbidity remains low.
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Affiliation(s)
- Sadia J Khan
- Centre for Plant and Water Sciences, Central Queensland University, Rockhampton, QLD 4701, Australia
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Khan SJ, Reed RH, Rasul MG. Thin-film fixed-bed reactor (TFFBR) for solar photocatalytic inactivation of aquaculture pathogen Aeromonas hydrophila. BMC Microbiol 2012; 12:5. [PMID: 22243515 PMCID: PMC3274425 DOI: 10.1186/1471-2180-12-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 01/13/2012] [Indexed: 11/29/2022] Open
Abstract
Background Outbreaks of infectious diseases by microbial pathogens can cause substantial losses of stock in aquaculture systems. There are several ways to eliminate these pathogens including the use of antibiotics, biocides and conventional disinfectants, but these leave undesirable chemical residues. Conversely, using sunlight for disinfection has the advantage of leaving no chemical residue and is particularly suited to countries with sunny climates. Titanium dioxide (TiO2) is a photocatalyst that increases the effectiveness of solar disinfection. In recent years, several different types of solar photocatalytic reactors coated with TiO2 have been developed for waste water and drinking water treatment. In this study a thin-film fixed-bed reactor (TFFBR), designed as a sloping flat plate reactor coated with P25 DEGUSSA TiO2, was used. Results The level of inactivation of the aquaculture pathogen Aeromonas hydrophila ATCC 35654 was determined after travelling across the TFFBR under various natural sunlight conditions (300-1200 W m-2), at 3 different flow rates (4.8, 8.4 and 16.8 L h-1). Bacterial numbers were determined by conventional plate counting using selective agar media, cultured (i) under conventional aerobic conditions to detect healthy cells and (ii) under conditions designed to neutralise reactive oxygen species (agar medium supplemented with the peroxide scavenger sodium pyruvate at 0.05% w/v, incubated under anaerobic conditions), to detect both healthy and sub-lethally injured (oxygen-sensitive) cells. The results clearly demonstrate that high sunlight intensities (≥ 600 W m-2) and low flow rates (4.8 L h-1) provided optimum conditions for inactivation of A. hydrophila ATCC 3564, with greater overall inactivation and fewer sub-lethally injured cells than at low sunlight intensities or high flow rates. Low sunlight intensities resulted in reduced overall inactivation and greater sub-lethal injury at all flow rates. Conclusions This is the first demonstration of the effectiveness of the TFFBR in the inactivation of Aeromonas hydrophila at high sunlight intensities, providing proof-of-concept for the application of solar photocatalysis in aquaculture systems.
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Affiliation(s)
- Sadia J Khan
- Centre for Plant and Water Sciences, Faculty of Sciences, Engineering and Health, CQUniversity, Rockhampton, QLD 4702, Australia
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Sharan R, Chhibber S, Reed RH. Inactivation and sub-lethal injury of salmonella typhi, salmonella typhimurium and vibrio cholerae in copper water storage vessels. BMC Infect Dis 2011; 11:204. [PMID: 21794163 PMCID: PMC3160999 DOI: 10.1186/1471-2334-11-204] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Accepted: 07/27/2011] [Indexed: 01/11/2023] Open
Abstract
Background This study provides information on the antibacterial effect of copper against the water-borne pathogens Salmonella Typhi, Salmonella Typhimurium and Vibrio cholerae. Methods Suspensions of each pathogen were kept in water within a traditional copper vessel at 30°C for 24 h. Samples were withdrawn, diluted and plated onto suitable growth media. Conventional enumeration of healthy (uninjured) bacteria was carried out using standard aerobic incubation conditions. Additionally, reactive oxygen species-neutralised (ROS-n) conditions were achieved by adding the peroxide scavenger sodium pyruvate to the medium with anaerobic incubation, to enumerate uninjured (ROS-insensitive) and injured (ROS-sensitive) bacteria. Differences between log-transformed means of conventional (aerobic) and ROS-n counts were statistically evaluated using t tests. Results Overall, all three pathogens were inactivated by storage in copper vessels for 24 h. However, for shorter-term incubation (4-12 h), higher counts were observed under ROS-n conditions than under aerobic conditions, which demonstrate the presence of substantial numbers of sub-lethally injured cells prior to their complete inactivation. Conclusions The present study has for the first time confirmed that these bacterial pathogens are inactivated by storage in a copper vessel within 24 h. However, it has also demonstrated that it is necessary to account for short-term sub-lethal injury, manifest as ROS-sensitivity, in order to more fully understand the process. This has important practical implications in terms of the time required to store water within a copper vessel to completely inactivate these bacteria and thereby remove the risk of water-borne disease transmission by this route.
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Affiliation(s)
- Riti Sharan
- Centre for Plant and Water Science, Faculty of Sciences, Engineering and Health, CQUniversity, Rockhampton, Queensland 4702, Australia
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A murine model to study the antibacterial effect of copper on infectivity of Salmonella enterica serovar Typhimurium. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2010; 8:21-36. [PMID: 21318012 PMCID: PMC3037058 DOI: 10.3390/ijerph8010021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2010] [Revised: 12/16/2010] [Accepted: 12/22/2010] [Indexed: 12/20/2022]
Abstract
This study investigated the effect of copper as an antibacterial agent on the infectivity of Salmonella enterica serovar Typhimurium. Mice were infected orally with a standardized dose of unstressed Salmonella Typhimurium and copper-stressed cells of Salmonella Typhimurium. Bacterial counts in ileum, blood, liver and spleen were observed up to 168 h under normal aerobic conditions. Serum sensitivity, phagocytosis, malondialdehyde levels and histopathology were studied for both set of animals. A decreased bacterial count in the organs with mild symptoms of infection and a complete recovery by 48 h was observed in mice infected with copper-stressed bacteria. Histopathological examination of ileum tissue demonstrated regeneration of damaged tissue post-infection with copper-stressed bacteria and no malondialdehyde levels were detected after 24 h in ileum, spleen and liver. Exposure to copper sensitized Salmonella Typhimurium to the lytic action of serum and intracellular killing by peritoneal macrophages. It can be concluded that copper stress confers a decrease in the infectivity of healthy Salmonella Typhimurium in normal mice. This study highlights the significance of use of copper as an antibacterial agent against Salmonella Typhimurium in reducing the risk of incidence of Salmonella infections from contaminated water.
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Sharan R, Chhibber S, Attri S, Reed RH. Inactivation and sub-lethal injury of Escherichia coli in a copper water storage vessel: effect of inorganic and organic constituents. Antonie van Leeuwenhoek 2010; 98:103-15. [PMID: 20358286 DOI: 10.1007/s10482-010-9435-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 03/22/2010] [Indexed: 01/11/2023]
Abstract
This study provides information on the effects of inorganic and organic constituents on inactivation and sub-lethal injury of Escherichia coli in water stored in a copper vessel. E. coli suspensions were stored for up to 24 h in copper vessels containing one of the following dissolved constituents at 1 g/l: salts of inorganic ions, carbohydrates, proteins and complex natural organic mixtures. Samples were surface plated onto (i) nutrient agar, incubated under standard aerobic conditions to provide conventional counts for uninjured bacteria count and onto (ii) nutrient agar plates with 0.5 g/l sodium pyruvate incubated under anaerobic conditions to enumerate sub-lethally injured (oxygen-sensitive) bacteria alongside their healthy counterparts. The concentration of dissolved copper in the stored water was determined using atomic absorption spectrophotometry. The addition of chloride salts resulted in a faster inactivation of E. coli compared to pure water with no dissolved additives, irrespective of the counterion. In contrast, a slower inactivation was observed in the presence of Na(2)SO(4), NaNO(3) and NaNO(2) when compared to NaCl. Addition of the carbohydrates glucose, lactose and starch gave broadly similar results to those obtained using unsupplemented water. However, the addition of amino acids, proteins, humic acid or complex organic mixtures caused a dramatic decrease in inactivation of E. coli, with evidence of a greater number of sub-lethally injured bacteria than was seen with other added constituents. The amount of copper was highest in stored water containing amino acids and complex organic constituents, with the slow inactivation most likely to be due to complex formation between leached copper and these organic constituents. The present study clearly demonstrates that water composition, particularly natural organic constituents, has a substantial impact on the antibacterial effectiveness and dissolved copper concentration of water stored in copper vessels and that both aspects will need to be considered in terms of their impact on the practical use of copper-based systems for small-scale water treatment.
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Affiliation(s)
- Riti Sharan
- Centre for Plant & Water Science, CQUniversity, Brisbane, Australia
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