1
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Chiang J, Robertson J, McGoverin CM, Swift S, Vanholsbeeck F. Rapid detection of viable microbes with 5-cyano-2,3-di-(p-tolyl)tetrazolium chloride and 5(6)-carboxyfluorescein diacetate using a fibre fluorescence spectroscopy system. J Appl Microbiol 2024; 135:lxae047. [PMID: 38383865 DOI: 10.1093/jambio/lxae047] [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: 11/26/2023] [Revised: 02/03/2024] [Accepted: 02/20/2024] [Indexed: 02/23/2024]
Abstract
AIMS To assess the efficacy of two commercially available viability dyes, 5-cyano-2,3-di-(p-tolyl)tetrazolium chloride (CTC) and 5(6)-carboxyfluorescein diacetate (CFDA), in reporting on viable cell concentration and species using an all-fibre fluorometer. METHODS AND RESULTS Four bacterial species (two Gram-positive and two Gram-negative) commonly associated with food poisoning or food spoilage (Escherichia coli, Salmonella enterica, Staphylococcus aureus, and Bacillus cereus) were stained with CTC or CFDA and the fibre fluorometer was used to collect full fluorescence emission spectra. A good correlation between concentration and fluorescence intensity was found for Gram-negative bacteria between 107 and 108 colony-forming units (CFU) ml-1. There was no correlation with concentration for Gram-positive bacteria; however, the information in the CTC and CFDA spectra shows the potential to distinguish Gram-negative cells from Gram-positive cells, although it may simply reflect the overall bacterial metabolic activity under staining conditions from this study. CONCLUSIONS The limit of detection (LoD) is too high in the dip-probe approach for analysis; however, the development of an approach measuring the fluorescence of single cells may improve this limitation. The development of new bacteria-specific fluorogenic dyes may also address this limitation. The ability to differentiate bacteria using these dyes may add value to measurements made to enumerate bacteria using CTC and CFDA.
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Affiliation(s)
- Jessica Chiang
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland 1023, New Zealand
| | - Julia Robertson
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland 1023, New Zealand
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Auckland 1010, New Zealand
| | - Cushla M McGoverin
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Auckland 1010, New Zealand
- Department of Physics, The University of Auckland, Auckland 1010, New Zealand
| | - Simon Swift
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland 1023, New Zealand
| | - Frédérique Vanholsbeeck
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Auckland 1010, New Zealand
- Department of Physics, The University of Auckland, Auckland 1010, New Zealand
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2
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Marcos-Fernández R, Sánchez B, Ruiz L, Margolles A. Convergence of flow cytometry and bacteriology. Current and future applications: a focus on food and clinical microbiology. Crit Rev Microbiol 2023; 49:556-577. [PMID: 35749433 DOI: 10.1080/1040841x.2022.2086035] [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: 07/19/2021] [Revised: 05/12/2022] [Accepted: 05/31/2022] [Indexed: 11/03/2022]
Abstract
Since its development in the 1960s, flow cytometry (FCM) was quickly revealed a powerful tool to analyse cell populations in medical studies, yet, for many years, was almost exclusively used to analyse eukaryotic cells. Instrument and methodological limitations to distinguish genuine bacterial signals from the background, among other limitations, have hampered FCM applications in bacteriology. In recent years, thanks to the continuous development of FCM instruments and methods with a higher discriminatory capacity to detect low-size particles, FCM has emerged as an appealing technique to advance the study of microbes, with important applications in research, clinical and industrial settings. The capacity to rapidly enumerate and classify individual bacterial cells based on viability facilitates the monitoring of bacterial presence in foodstuffs or clinical samples, reducing the time needed to detect contamination or infectious processes. Besides, FCM has stood out as a valuable tool to advance the study of complex microbial communities, or microbiomes, that are very relevant in the context of human health, as well as to understand the interaction of bacterial and host cells. This review highlights current developments in, and future applications of, FCM in bacteriology, with a focus on those related to food and clinical microbiology.
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Affiliation(s)
- Raquel Marcos-Fernández
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
| | - Borja Sánchez
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
| | - Lorena Ruiz
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
| | - Abelardo Margolles
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
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3
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Zhou M, Cai Q, Zhang C, Ouyang P, Yu L, Xu Y. Antibiotic resistance bacteria and antibiotic resistance genes survived from the extremely acidity posing a risk on intestinal bacteria in an in vitro digestion model by horizontal gene transfer. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 247:114247. [PMID: 36332408 DOI: 10.1016/j.ecoenv.2022.114247] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 10/24/2022] [Accepted: 10/26/2022] [Indexed: 06/16/2023]
Abstract
Antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) are emerging contaminants posing risk to human health. To investigate the pathogenic ARBs and the horizontal gene transfer (HGT) via both extracellular ARGs (eARGs) and intracellular ARGs (iARGs), an in vitro digestion simulation system was established to monitoring the ARB and ARGs passing through the artificial digestive tract. The results showed that ARB was mostly affected by the acidity of the gastric fluid with about 99% ARB (total population of 2.45 × 109-2.54 × 109) killed at pH 2.0 and severe damage of bacterial cell membrane. However, more than 80% ARB (total population of 2.71 × 109-3.90 × 109) survived the challenge when the pH of the gastric fluid was 3.0 and above. Most ARB died from the high acidity, but its ARGs, intI1 and 16 S rRNA could be detected. The eARGs (accounting for 0.03-24.56% of total genes) were less than iARGs obviously. The eARGs showed greater HGT potential than that of iARGs, suggesting that transformation occurred more easily than conjugation. The transferring potential followed: tet (100%) > sul (75%) > bla (58%), related to the high correlation of intI1 with tetA and sul2 (p < 0.01). Moreover, gastric juice of pH 1.0 could decrease the transfer frequency of ARGs by 2-3 order of magnitude compared to the control, but still posing potential risks to human health. Under the treatment of digestive fluid, ARGs showed high gene horizontal transfer potential, suggesting that food-borne ARBs pose a great risk of horizontal transfer of ARGs to intestinal bacteria.
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Affiliation(s)
- Min Zhou
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China; School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China
| | - Qiujie Cai
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Chaonan Zhang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Pengqian Ouyang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Ling Yu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China; Center of Analysis and Test, Guangdong University of Technology, Guangzhou 510006, China
| | - Yanbin Xu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China; Center of Analysis and Test, Guangdong University of Technology, Guangzhou 510006, China.
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4
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Li Z, Xu L, Yuan H, Zhang P. Fluorescent sensor array based on aggregation-induced emission luminogens for pathogen discrimination. Analyst 2022; 147:2930-2935. [PMID: 35611940 DOI: 10.1039/d2an00643j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A high-throughput tetraphenylethylene (TPE)-based fluorescent sensor array was constructed for the identification and detection of microorganisms, which utilizes three TPE derivatives with different numbers of cationic side chains to detect and discriminate various microorganisms at concentrations down to 1 × 103 CFU mL-1.
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Affiliation(s)
- Zelin Li
- Department of Chemistry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, P. R. China.
| | - Li Xu
- Department of Pharmacy, Hubei University of Chinese Medicine, Wuhan 430065, P. R. China
| | - Huanxiang Yuan
- Department of Chemistry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, P. R. China.
| | - Pengbo Zhang
- School of Chemistry and Biological Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing, 100083, China.
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5
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Wang Z, Wang M, Xu Q, Liu S, Gao Y, Chang H, Sui Z. Rapid and Multiplexed Detection of Single Cells of Salmonella, Escherichia coli O157, and Shigella flexneri in Ground Beef by Flow Cytometry. Foodborne Pathog Dis 2022; 19:272-280. [PMID: 35263171 DOI: 10.1089/fpd.2021.0088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Salmonella, Escherichia coli O157, and Shigella flexneri are typical foodborne pathogens in ground beef, which can cause severe infection even when present as a single cell. Flow cytometry (FCM) methods are widely applied in the rapid detection of pathogens in food products. In this study, we report an FCM-based method for detecting single cells of Salmonella, E. coli O157, and S. flexneri in 25 g ground beef samples. We fluorescently labeled specific antibodies that could effectively identify bacterial cells, prepared single-cell samples by serial dilution, and optimized the pre-enrichment time. The results showed that 7 h of pre-enrichment is appropriate for sensitive single-cell detection by FCM. Finally, we evaluated this method in artificially contaminated and retail beef samples. This study outlines a novel highly sensitive FCM-based method to detect Salmonella, E. coli O157, and S. flexneri in beef samples within 8 h that can be applied to the rapid and multiplexed detection of foodborne pathogens.
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Affiliation(s)
- Ziquan Wang
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, China
| | - Meng Wang
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, China
| | - Qian Xu
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, China.,College of Life Sciences, Hunan Normal University, Changsha, China
| | - Siyuan Liu
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, China
| | - Ying Gao
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, China
| | - Haiyan Chang
- College of Life Sciences, Hunan Normal University, Changsha, China
| | - Zhiwei Sui
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, China
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6
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Conjugated polymer materials for detection and discrimination of pathogenic microorganisms: Guarantee of biosafety. BIOSAFETY AND HEALTH 2022. [DOI: 10.1016/j.bsheal.2022.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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7
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Wang Z, Xu Q, Liu S, Liu Y, Gao Y, Wang M, Zhang L, Chang H, Wei Q, Sui Z. Rapid and multiplexed quantification of Salmonella, Escherichia coli O157:H7, and Shigella flexneri in ground beef using flow cytometry. Talanta 2022; 238:123005. [PMID: 34857336 DOI: 10.1016/j.talanta.2021.123005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 10/14/2021] [Accepted: 10/26/2021] [Indexed: 12/14/2022]
Abstract
Salmonella, Escherichia coli O157:H7 (E. coli O157:H7) and Shigella flexneri (S. flexneri) might contaminate similar types of meat products and cause deadly diseases in humans. In reality, ground beef samples may carry more than one pathogen and a rapid and accurate detection method for the simultaneous identification of multiple specific pathogenic strains in ground beef is crucial. In this study, a sample pretreatment protocol and a flow cytometry method were developed for rapid and multiplexed quantification of the three pathogens without cultural enrichment in ground beef. The whole process of sample pretreatment, staining, and instrument analysis can be accomplished within 1 h. The three bacteria upon sample pretreatment were demonstrated good recoveries (93.8%-101.2%). The quantitative detection range of the mothed was 103 to 108 cells/g for all three pathogens, and the detection limit for Salmonella, E. coli O157:H7 and S. flexneri in ground beef were 3.1 × 103 cells/g, 2.1 × 103 cells/g and 2.3 × 103 cells/g, respectively. Therefore, the as-developed approach is a rapid and quantitative method for multiplexed detection of Salmonella, E. coli O157:H7, and S. flexneri in ground beef.
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Affiliation(s)
- Ziquan Wang
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China
| | - Qian Xu
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China; College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Siyuan Liu
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China
| | - Yingying Liu
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China
| | - Ying Gao
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China
| | - Meng Wang
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China
| | - Ling Zhang
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China
| | - Haiyan Chang
- College of Life Sciences, Hunan Normal University, Changsha, 410081, China
| | - Qiang Wei
- National Pathogen Resource Center, Chinese Center for Disease Control and Prevention, Beijing, 102206, China.
| | - Zhiwei Sui
- Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China.
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8
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Kawai M. [Environmental Monitoring in a Pharmaceutical Manufacturing Facility Using a Culture Independent Approach]. YAKUGAKU ZASSHI 2022; 142:33-37. [PMID: 34980749 DOI: 10.1248/yakushi.21-00161-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Strict microbial control is required in manufacturing facilities to ensure the quality of pharmaceuticals and foods. Environmental microbial monitoring plays a fundamental role in reducing the risk of microbial contamination. Appropriate microbial control requires an understanding of abundance and community structures of microbes in the target environment. However, most of these microbes are not culturable using conventional methods. In this study, we determined the number of microbial particles and assessed the environmental microbiome in a pharmaceutical manufacturing facility, using high-throughput sequencing of rRNA gene fragments. Our results provide fundamental data for the evaluation and control of microbes in the pharmaceutical and food industries.
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Affiliation(s)
- Mako Kawai
- Faculty of Pharmaceutical Sciences, Himeji Dokkyo University
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9
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Campelo TA, Cardoso de Sousa PR, Nogueira LDL, Frota CC, Zuquim Antas PR. Revisiting the methods for detecting Mycobacterium tuberculosis: what has the new millennium brought thus far? Access Microbiol 2021; 3:000245. [PMID: 34595396 PMCID: PMC8479963 DOI: 10.1099/acmi.0.000245] [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: 02/23/2021] [Accepted: 06/17/2021] [Indexed: 01/07/2023] Open
Abstract
Tuberculosis (TB) affects around 10 million people worldwide in 2019. Approximately 3.4 % of new TB cases are multidrug-resistant. The gold standard method for detecting Mycobacterium tuberculosis, which is the aetiological agent of TB, is still based on microbiological culture procedures, followed by species identification and drug sensitivity testing. Sputum is the most commonly obtained clinical specimen from patients with pulmonary TB. Although smear microscopy is a low-cost and widely used method, its sensitivity is 50-60 %. Thus, owing to the need to improve the performance of current microbiological tests to provide prompt treatment, different methods with varied sensitivity and specificity for TB diagnosis have been developed. Here we discuss the existing methods developed over the past 20 years, including their strengths and weaknesses. In-house and commercial methods have been shown to be promising to achieve rapid diagnosis. Combining methods for mycobacterial detection systems demonstrates a correlation of 100 %. Other assays are useful for the simultaneous detection of M. tuberculosis species and drug-related mutations. Novel approaches have also been employed to rapidly identify and quantify total mycobacteria RNA, including assessments of global gene expression measured in whole blood to identify the risk of TB. Spoligotyping, mass spectrometry and next-generation sequencing are also promising technologies; however, their cost needs to be reduced so that low- and middle-income countries can access them. Because of the large impact of M. tuberculosis infection on public health, the development of new methods in the context of well-designed and -controlled clinical trials might contribute to the improvement of TB infection control.
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Affiliation(s)
- Thales Alves Campelo
- Faculdade de Medicina, Departamento de Patologia e Medicina Legal, Federal University of Ceará, Fortaleza, Brazil
| | | | - Lucas de Lima Nogueira
- Faculdade de Medicina, Departamento de Patologia e Medicina Legal, Federal University of Ceará, Fortaleza, Brazil
| | - Cristiane Cunha Frota
- Faculdade de Medicina, Departamento de Patologia e Medicina Legal, Federal University of Ceará, Fortaleza, Brazil
| | - Paulo Renato Zuquim Antas
- Laboratório de Imunologia Clínica, Instituto Oswaldo Cruz, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
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10
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Li Z, Lu W, Jia S, Yuan H, Gao LH. Design and Application of Conjugated Polymer Nanomaterials for Detection and Inactivation of Pathogenic Microbes. ACS APPLIED BIO MATERIALS 2020; 4:370-386. [DOI: 10.1021/acsabm.0c01395] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Zelin Li
- Department of Chemistry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, P. R. China
| | - Wen Lu
- Department of Chemistry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, P. R. China
| | - Shaochuan Jia
- Department of Chemistry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, P. R. China
| | - Huanxiang Yuan
- Department of Chemistry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, P. R. China
| | - Li-Hua Gao
- Department of Chemistry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, P. R. China
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11
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Bartle L, Mitchell JG, Paterson JS. Evaluating the Cytometric Detection and Enumeration of the Wine Bacterium, Oenococcus oeni. Cytometry A 2020; 99:399-406. [PMID: 33140503 DOI: 10.1002/cyto.a.24258] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 12/29/2022]
Abstract
Flow cytometry is a high-throughput tool for determining microbial abundance in a range of medical, environmental, and food-related samples. For wine, determining the abundance of Saccharomyces cerevisiae is well-defined and reliable. However, for the most common wine bacterium, Oenococcus oeni, using flow cytometry to determine cell concentration poses some challenges. O. oeni most often occurs in doublets or chains of varying lengths that can be greater than seven cells. This wine bacterium is also small, at 0.2-0.6 μm and may exhibit a range of morphologies including binary fission and aggregated complexes. This work demonstrates a straightforward approach to determining the suitability of flow cytometry for the chain-forming bacteria, O. oeni, and considerations when using flow cytometry for the enumeration of small microorganisms (<0.5 μm). © 2020 International Society for Advancement of Cytometry.
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Affiliation(s)
- Louise Bartle
- Department of Wine and Food Science, The University of Adelaide, Urrbrae, Australia.,Department of Microbiology and Infectious Diseases, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - James G Mitchell
- Flinders University, College of Science and Engineering, Adelaide, Australia
| | - James S Paterson
- Flinders University, College of Science and Engineering, Adelaide, Australia
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12
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Preparation of natural indicator incorporated media and its logical use as a colorimetric biosensor for rapid and sensitive detection of Methicillin-resistant Staphylococcus aureus. Anal Chim Acta 2020; 1128:80-89. [DOI: 10.1016/j.aca.2020.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/28/2020] [Accepted: 06/01/2020] [Indexed: 12/29/2022]
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13
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Tokunaga Y, Yamaguchi N. Rapid quantification of
Escherichia coli
O157
:
H7
in lettuce and beef using an on‐chip staining microfluidic device. J Food Saf 2020. [DOI: 10.1111/jfs.12851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Yusuke Tokunaga
- Division of Hygienic Chemistry Osaka Institute of Public Health Osaka Japan
| | - Nobuyasu Yamaguchi
- Division of Hygienic Chemistry Osaka Institute of Public Health Osaka Japan
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14
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Rapid On-Site Detection and Quantification of Foodborne Pathogens Using Microfluidic Devices. Methods Mol Biol 2019. [PMID: 30580399 DOI: 10.1007/978-1-4939-9000-9_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The potential for foodborne infectious disease outbreaks has increased not only on a local scale but also on a regional and international scale. Simple, rapid, and accurate methods to enumerate pathogenic bacteria in food and drink are required to prevent the spread of these bacteria. Here, I describe applications of a microfluidic device for on-chip fluorescent staining and semiautomated counting of target bacteria in food samples.
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15
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Liu S, Sui Z, Lin J, Huo N, Yang J, Wang B, Gu S. Rapid detection of single viableEscherichia coliO157:H7 cells in milk by flow cytometry. J Food Saf 2019. [DOI: 10.1111/jfs.12657] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Siyuan Liu
- Shanxi Key Laboratory of Environmental Veterinary Medicine, College of Animal Science and Veterinary MedicineShanxi Agricultural University Taigu Shanxi China
- Center for Advanced Measurement ScienceNational Institute of Metrology Beijing China
| | - Zhiwei Sui
- Center for Advanced Measurement ScienceNational Institute of Metrology Beijing China
| | - Jing Lin
- Department of BiometrologyInstitute of Measurement and Testing Technology Nanjing Jiangsu China
| | - Nairui Huo
- Shanxi Key Laboratory of Environmental Veterinary Medicine, College of Animal Science and Veterinary MedicineShanxi Agricultural University Taigu Shanxi China
| | - Jiayi Yang
- Center for Advanced Measurement ScienceNational Institute of Metrology Beijing China
| | - Bin Wang
- Center for Advanced Measurement ScienceNational Institute of Metrology Beijing China
- Research Center for Ginseng Genetic Resources Development and UtilizationJilin Agricultural University Jilin China
| | - Shaopeng Gu
- Shanxi Key Laboratory of Environmental Veterinary Medicine, College of Animal Science and Veterinary MedicineShanxi Agricultural University Taigu Shanxi China
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16
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17
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Tsakama M, Ma X, He Y, Chen W, Dai X. A Simple Mannose-Coated Poly (p-Phenylene Ethynylene) for Qualitative Bacterial Capturing. Molecules 2018; 23:molecules23082056. [PMID: 30115873 PMCID: PMC6222808 DOI: 10.3390/molecules23082056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 08/09/2018] [Accepted: 08/14/2018] [Indexed: 12/02/2022] Open
Abstract
A mannose-functionalized poly (p-phenylene ethynylene) was rationally designed to achieve selective detection of bacteria. The polymer was constructed as a signaling unit and was modified by attaching aminoethyl mannose using the carboxylic acid group at the end of the linker. Incubation of Escherichia coli with the polymer yielded fluorescent bacteria aggregates through polyvalent interactions. The utility of the mannose functionalized polymer to detect E. coli expressing functional FimH mannose-specific lectin on their surface was also demonstrated. The sugar units displayed on the surface of the polymer retained their functional ability to interact with mannose-binding lectin. To determine the optimum binding time, we measured the fluorescence intensity of the polymer-bacteria suspension at intervals. Our results showed that binding in this system will reach an optimum level within 30 min of incubation. The polymer’s affinity for bacteria has been demonstrated and bacteria with a concentration of 103 CFU mL−1 can be detected by this system.
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Affiliation(s)
- Madalitso Tsakama
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| | - Xiaochi Ma
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| | - Yonghuan He
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| | - Weihua Chen
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
- Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture, Beijing 100193, China.
| | - Xiaofeng Dai
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
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18
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Zeinhom MMA, Wang Y, Song Y, Zhu MJ, Lin Y, Du D. A portable smart-phone device for rapid and sensitive detection of E. coli O157:H7 in Yoghurt and Egg. Biosens Bioelectron 2018; 99:479-485. [DOI: 10.1016/j.bios.2017.08.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/28/2017] [Accepted: 08/02/2017] [Indexed: 01/08/2023]
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19
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Castillo DS, Rey Serantes DA, Melli LJ, Ciocchini AE, Ugalde JE, Comerci DJ, Cassola A. A recombinant O-polysaccharide-protein conjugate approach to develop highly specific monoclonal antibodies to Shiga toxin-producing Escherichia coli O157 and O145 serogroups. PLoS One 2017; 12:e0182452. [PMID: 28981517 PMCID: PMC5628784 DOI: 10.1371/journal.pone.0182452] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 09/08/2017] [Indexed: 01/07/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) is the major etiologic agent of hemolytic-uremic syndrome (HUS). The high rate of HUS emphasizes the urgency for the implementation of primary prevention strategies to reduce its public health impact. Argentina shows the highest rate of HUS worldwide, being E. coli O157 the predominant STEC-associated HUS serogroup (>70%), followed by E. coli O145 (>9%). To specifically detect these serogroups we aimed at developing highly specific monoclonal antibodies (mAbs) against the O-polysaccharide (O-PS) section of the lipopolysaccharide (LPS) of the dominant STEC-associated HUS serogroups in Argentina. The development of hybridomas secreting mAbs against O157 or O145 was carried out through a combined immunization strategy, involving adjuvated-bacterial immunizations followed by immunizations with recombinant O-PS-protein conjugates. We selected hybridoma clones that specifically recognized the engineered O-PS-protein conjugates of O157 or O145 serogroups. Indirect ELISA of heat-killed bacteria showed specific binding to O157 or O145 serogroups, respectively, while no cross-reactivity with other epidemiological important STEC strains, Brucella abortus, Salmonella group N or Yersinia enterocolitica O9 was observed. Western blot analysis showed specific recognition of the sought O-PS section of the LPS by all mAbs. Finally, the ability of the developed mAbs to bind the surface of whole bacteria cells was confirmed by flow cytometry, confocal microscopy and agglutination assays, indicating that these mAbs present an exceptional degree of specificity and relative affinity in the detection and identification of E. coli O157 and O145 serogroups. These mAbs may be of significant value for clinical diagnosis and food quality control applications. Thus, engineered O-PS specific moieties contained in the recombinant glycoconjugates used for combined immunization and hybridoma selection are an invaluable resource for the development of highly specific mAbs.
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Affiliation(s)
- Daniela S. Castillo
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, Buenos Aires, Argentina
| | - Diego A. Rey Serantes
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, Buenos Aires, Argentina
| | - Luciano J. Melli
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, Buenos Aires, Argentina
| | - Andrés E. Ciocchini
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, Buenos Aires, Argentina
| | - Juan E. Ugalde
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, Buenos Aires, Argentina
| | - Diego J. Comerci
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, Buenos Aires, Argentina
| | - Alejandro Cassola
- Instituto de Investigaciones Biotecnológicas - Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Martín, Buenos Aires, Argentina
- * E-mail:
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Rapid on-site monitoring of Legionella pneumophila in cooling tower water using a portable microfluidic system. Sci Rep 2017; 7:3092. [PMID: 28596545 PMCID: PMC5465085 DOI: 10.1038/s41598-017-03293-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 04/26/2017] [Indexed: 11/09/2022] Open
Abstract
Legionnaires' disease, predominantly caused by the bacterium Legionella pneumophila, has increased in prevalence worldwide. The most common mode of transmission of Legionella is inhalation of contaminated aerosols, such as those generated by cooling towers. Simple, rapid and accurate methods to enumerate L. pneumophila are required to prevent the spread of this organism. Here, we applied a microfluidic device for on-chip fluorescent staining and semi-automated counting of L. pneumophila in cooling tower water. We also constructed a portable system for rapid on-site monitoring and used it to enumerate target bacterial cells rapidly flowing in the microchannel. A fluorescently-labelled polyclonal antibody was used for the selective detection of L. pneumophila serogroup 1 in the samples. The counts of L. pneumophila in cooling tower water obtained using the system and fluorescence microscopy were similar. The detection limit of the system was 104 cells/ml, but lower numbers of L. pneumophila cells (101 to 103 cells/ml) could be detected following concentration of 0.5-3 L of the water sample by filtration. Our technique is rapid to perform (1.5 h), semi-automated (on-chip staining and counting), and portable for on-site measurement, and it may therefore be effective in the initial screening of Legionella contamination in freshwater.
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21
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Xiang K, Li Y, Ford W, Land W, Schaffer JD, Congdon R, Zhang J, Sadik O. Automated analysis of food-borne pathogens using a novel microbial cell culture, sensing and classification system. Analyst 2017; 141:1472-82. [PMID: 26818563 DOI: 10.1039/c5an02614h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We hereby report the design and implementation of an Autonomous Microbial Cell Culture and Classification (AMC(3)) system for rapid detection of food pathogens. Traditional food testing methods require multistep procedures and long incubation period, and are thus prone to human error. AMC(3) introduces a "one click approach" to the detection and classification of pathogenic bacteria. Once the cultured materials are prepared, all operations are automatic. AMC(3) is an integrated sensor array platform in a microbial fuel cell system composed of a multi-potentiostat, an automated data collection system (Python program, Yocto Maxi-coupler electromechanical relay module) and a powerful classification program. The classification scheme consists of Probabilistic Neural Network (PNN), Support Vector Machines (SVM) and General Regression Neural Network (GRNN) oracle-based system. Differential Pulse Voltammetry (DPV) is performed on standard samples or unknown samples. Then, using preset feature extractions and quality control, accepted data are analyzed by the intelligent classification system. In a typical use, thirty-two extracted features were analyzed to correctly classify the following pathogens: Escherichia coli ATCC#25922, Escherichia coli ATCC#11775, and Staphylococcus epidermidis ATCC#12228. 85.4% accuracy range was recorded for unknown samples, and within a shorter time period than the industry standard of 24 hours.
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Affiliation(s)
- Kun Xiang
- Center for Advanced Sensors & Environmental Systems (CASE), Department of Chemistry, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA.
| | - Yinglei Li
- Department of Biomedical Engineering, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA
| | - William Ford
- Department of Biomedical Engineering, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA
| | - Walker Land
- Department of Biomedical Engineering, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA
| | - J David Schaffer
- Department of Biomedical Engineering, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA
| | - Robert Congdon
- Center for Advanced Sensors & Environmental Systems (CASE), Department of Chemistry, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA.
| | - Jing Zhang
- Center for Advanced Sensors & Environmental Systems (CASE), Department of Chemistry, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA.
| | - Omowunmi Sadik
- Center for Advanced Sensors & Environmental Systems (CASE), Department of Chemistry, State University of New York at Binghamton, P.O Box 6000, Binghamton, NY 13902, USA.
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22
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Ozawa S, Okabe S, Ishii S. Specific Single-Cell Isolation of Escherichia coli O157 from Environmental Water Samples by Using Flow Cytometry and Fluorescence-Activated Cell Sorting. Foodborne Pathog Dis 2016; 13:456-61. [PMID: 27182755 DOI: 10.1089/fpd.2016.2125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Contamination of food and water with pathogenic bacteria is of concern. Although culture-independent detection and quantification of pathogens is useful, isolation of pathogenic bacteria is still important when identifying the sources of pathogens. Here, we report the use of flow cytometry (FCM) and fluorescence-activated cell sorting (FACS) to specifically detect and isolate individual Escherichia coli O157:H7 cells from water samples. When present at >10 cells/mL water, target pathogen was specifically detected and isolated. The FACS-sorted E. coli O157:H7 population reflected the original population diversity, in contrast to the populations obtained by immunomagnetic separation. Relative abundance of multiple pathogenic strains is important when performing source-tracking studies; therefore, single-cell isolation with FCM-FACS can be a useful tool to obtain pathogenic bacteria for source tracking purpose.
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Affiliation(s)
- Shuji Ozawa
- 1 Division of Environmental Engineering, Hokkaido University , Sapporo, Japan
| | - Satoshi Okabe
- 1 Division of Environmental Engineering, Hokkaido University , Sapporo, Japan
| | - Satoshi Ishii
- 1 Division of Environmental Engineering, Hokkaido University , Sapporo, Japan .,2 Department of Soil, Water, and Climate, BioTechnology Institute, University of Minnesota , St. Paul, Minnesota
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23
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Ravan H, Amandadi M, Sanadgol N. A highly specific and sensitive loop-mediated isothermal amplification method for the detection of Escherichia coli O157:H7. Microb Pathog 2015; 91:161-5. [PMID: 26724736 DOI: 10.1016/j.micpath.2015.12.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 12/19/2015] [Accepted: 12/22/2015] [Indexed: 01/25/2023]
Abstract
E. coli O157:H7 is one of the most important foodborne pathogen that causes some human illnesses such as bloody diarrhea, hemolytic-uremic syndrome, and kidney failure. We developed a loop-mediated isothermal amplification (LAMP) assay with six special primers that target a highly specific 299-bp region of the Z3276 gene for the detection of E. coli O157:H7. Among 117 bacterial strains tested in this study, positive results were only obtained from E. coli O157:H7 strains. The sensitivity level of the Z3276-LAMP assay was determined to be 5 CFU/reaction tube in pure bacterial culture. Moreover, the LAMP assay was successfully applied to artificially contaminated ground beef with a sensitivity level of 10(3) CFU/mL without pre-enrichment and 10 CFU/mL after a 4-h pre-enrichment. In conclusion, the present LAMP assay would be a useful and powerful tool for the rapid, sensitive, and specific diagnosis of E. coli O157:H7 strains in resource limited laboratories.
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Affiliation(s)
- Hadi Ravan
- Department of Biology, Faculty of Science, Shahid Bahonar University of Kerman, Kerman, Iran.
| | - Mojdeh Amandadi
- Department of Biology, Faculty of Science, Shahid Bahonar University of Kerman, Kerman, Iran
| | - Nima Sanadgol
- Department of Biology, Faculty of Science, Zabol University, Zabol, Iran; Pharmaceutical Science Research Center (PSRC), Tehran University of Medical Sciences (TUMS), Tehran, Iran
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24
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Anvarian AHP, Smith MP, Overton TW. The effects of orange juice clarification on the physiology of Escherichia coli; growth-based and flow cytometric analysis. Int J Food Microbiol 2015; 219:38-43. [PMID: 26705746 DOI: 10.1016/j.ijfoodmicro.2015.11.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 10/17/2015] [Accepted: 11/28/2015] [Indexed: 11/27/2022]
Abstract
Orange juice (OJ) is a food product available in various forms which can be processed to a greater or lesser extent. Minimally-processed OJ has a high consumer perception but presents a potential microbiological risk due to acid-tolerant bacteria. Clarification of OJ (such as removal of cloud) is a common processing step in many OJ products. However, many of the antimicrobial components of OJ such as essential oils are present in the cloud fraction. Here, the effect of clarification by filtration on the viability and physiology of Escherichia coli K-12 was tested using total viable count (TVC) and flow cytometric (FCM) analysis. The latter technique was also used to monitor intracellular pH during incubation in OJ. Removal of the OJ cloud fraction was shown to have dramatic effects on bacterial viability and physiology during storage at a range of incubation temperatures. For instance, at 4 °C, a significantly lower number of healthy cells and a significantly higher number of injured cells were observed in 0.22 μm-filtered OJ at 24h post-inoculation, compared to filtered OJ samples containing particles between 0.22 μm and 11 μm in size. Similarly, there was a significant difference between the number of healthy bacteria in the 0.7 μm-filtered OJ and both 0.22 μm-filtered and 1.2 μm-filtered OJ after 24 hour incubation at 22.5 °C. This indicated that OJ cloud between 0.7 μm and 0.22 μm in size might have an adverse effect on the viability of E. coli K-12. Furthermore, FCM allowed the rapid analysis of bacterial physiology without the requirement for growth on agar plates, and revealed the extent of the viable but non-culturable (VBNC) population. For example, at 4 °C, while the FCM viable count did not substantially decrease until 48 h, decreases in TVC were observed between 0 and 48 hour incubation, due to a subset of injured bacteria entering the VBNC state, hence being unable to grow on agar plates. This study highlights the application of FCM in monitoring bacterial physiology in foods, and potential effects of OJ clarification on bacterial physiology.
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Affiliation(s)
- Amir H P Anvarian
- Bioengineering, School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Madeleine P Smith
- Bioengineering, School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Tim W Overton
- Bioengineering, School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, United Kingdom; Institute of Microbiology & Infection, University of Birmingham, Birmingham B15 2TT, United Kingdom.
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25
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Bridier A, Hammes F, Canette A, Bouchez T, Briandet R. Fluorescence-based tools for single-cell approaches in food microbiology. Int J Food Microbiol 2015; 213:2-16. [PMID: 26163933 DOI: 10.1016/j.ijfoodmicro.2015.07.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 06/26/2015] [Accepted: 07/03/2015] [Indexed: 12/31/2022]
Abstract
The better understanding of the functioning of microbial communities is a challenging and crucial issue in the field of food microbiology, as it constitutes a prerequisite to the optimization of positive and technological microbial population functioning, as well as for the better control of pathogen contamination of food. Heterogeneity appears now as an intrinsic and multi-origin feature of microbial populations and is a major determinant of their beneficial or detrimental functional properties. The understanding of the molecular and cellular mechanisms behind the behavior of bacteria in microbial communities requires therefore observations at the single-cell level in order to overcome "averaging" effects inherent to traditional global approaches. Recent advances in the development of fluorescence-based approaches dedicated to single-cell analysis provide the opportunity to study microbial communities with an unprecedented level of resolution and to obtain detailed insights on the cell structure, metabolism activity, multicellular behavior and bacterial interactions in complex communities. These methods are now increasingly applied in the field of food microbiology in different areas ranging from research laboratories to industry. In this perspective, we reviewed the main fluorescence-based tools used for single-cell approaches and their concrete applications with specific focus on food microbiology.
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Affiliation(s)
| | - F Hammes
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - A Canette
- INRA, UMR1319 Micalis, Jouy-en-Josas, France; AgroParisTech, UMR Micalis, Jouy-en-Josas, France
| | | | - R Briandet
- INRA, UMR1319 Micalis, Jouy-en-Josas, France; AgroParisTech, UMR Micalis, Jouy-en-Josas, France.
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26
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Lin HC, Lin JJ, Sheng YJ. Interaction of novel fluorescent nanoscale ionic silicate platelets with biomaterials for biosensors. ACS APPLIED MATERIALS & INTERFACES 2015; 7:10771-10778. [PMID: 25938175 DOI: 10.1021/acsami.5b00796] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The nano silicate platelets (NSPs) of 100 × 100 × 1 nm(3) in dimension were previously derived from the exfoliation of naturally occurring sodium montmorillonite clay, and their affinity to the surface of bacteria was revealed. The unique characteristics of ionic charges (≡Si-O-Na(+)) and the presence of siloxanol functionalities (≡Si-OH) allowed the organic modification of NSP to form NSP-tethering poly(hydroxyethyl methacrylate) (PHEMA) pendants through a sol-gel and living polymerization. By attaching nathphalimide-type fluorescence onto NSP-PHEMA, a new class of fluorescent organic-inorganic hybrid (NSP-PHEMA-HA), was prepared and its photoluminescence (PL) and bacterial trapping properties were characterized. The investigation of PL emission revealed that the fluorescent NSP hybrids could be used to detect bacteria and possess the potential for the biosensor applications.
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Affiliation(s)
- Hsiao-Chu Lin
- †Institute of Polymer Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - Jiang-Jen Lin
- †Institute of Polymer Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - Yu-Jane Sheng
- †Institute of Polymer Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan
- ‡Department of Chemical Engineering, National Taiwan University, Taipei, 10617, Taiwan
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27
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Baker CA, Rubinelli PM, Park SH, Ricke SC. Immuno-based detection of Shiga toxin-producing pathogenic Escherichia coli in food – A review on current approaches and potential strategies for optimization. Crit Rev Microbiol 2015; 42:656-75. [DOI: 10.3109/1040841x.2015.1009824] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Christopher A. Baker
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
| | - Peter M. Rubinelli
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
| | - Si Hong Park
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
| | - Steven C. Ricke
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
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28
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Guo T, Wei Y, Xu C, Watts BR, Zhang Z, Fang Q, Zhang H, Selvaganapathy PR, Deen MJ. Counting ofEscherichia coliby a microflow cytometer based on a photonic-microfluidic integrated device. Electrophoresis 2014; 36:298-304. [DOI: 10.1002/elps.201400211] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 10/06/2014] [Accepted: 10/09/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Tianyi Guo
- School of Biomedical Engineering; McMaster University; Hamilton Canada
- Institute of Microelectronics; Chinese Academy of Science; Beijing China
| | - Yin Wei
- Department of Engineering Physics; McMaster University; Hamilton Canada
| | - Changqing Xu
- Department of Engineering Physics; McMaster University; Hamilton Canada
| | - Benjamin R. Watts
- Department of Engineering Physics; McMaster University; Hamilton Canada
| | - Zhiyi Zhang
- Information and Communication Technologies; National Research Council of Canada; Ottawa Canada
| | - Qiyin Fang
- School of Biomedical Engineering; McMaster University; Hamilton Canada
- Department of Engineering Physics; McMaster University; Hamilton Canada
| | - Haiying Zhang
- Institute of Microelectronics; Chinese Academy of Science; Beijing China
| | | | - M. Jamal Deen
- School of Biomedical Engineering; McMaster University; Hamilton Canada
- Department of Electrical and Computer Engineering; McMaster University; Hamilton Canada
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29
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Mortari A, Lorenzelli L. Recent sensing technologies for pathogen detection in milk: A review. Biosens Bioelectron 2014; 60:8-21. [DOI: 10.1016/j.bios.2014.03.063] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 03/07/2014] [Accepted: 03/26/2014] [Indexed: 01/30/2023]
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30
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Application of a Fluorescence Microscopy Technique for Detecting Viable Mycobacterium avium ssp. paratuberculosis Cells in Milk. FOOD ANAL METHOD 2014. [DOI: 10.1007/s12161-014-9918-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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31
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Yazgan I, Noah NM, Toure O, Zhang S, Sadik OA. Biosensor for selective detection of E. coli in spinach using the strong affinity of derivatized mannose with fimbrial lectin. Biosens Bioelectron 2014; 61:266-73. [PMID: 24906084 DOI: 10.1016/j.bios.2014.05.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 04/29/2014] [Accepted: 05/04/2014] [Indexed: 11/18/2022]
Abstract
Escherichia coli (E. coli) contamination in foods and water resources represents a major threat for human health and the environment. This work exploits the strong affinity of mannose-containing oligosaccharides with the fimbrial lectin of E. coli to design novel biosensors. Modified carbohydrate ligands were synthesized by introducing phenyl residues and aliphatic chains to mannose via reductive amination in order to increase both the affinity and selectivity to E. coli compared to other pathogenic bacteria. The synthesized ligands include p-thiolphenyl aminomannose (PTAM), p-carboxyphenyl aminomannose (PCAM), 1-deoxy-1-aminomannopyranoside (DAMP), glucosamine and low molecular weight chitosan bonded to mercapto undecanoic acid. The structures of the ligands were confirmed using (1)H NMR and 1H, (13)C, COZY NMR, and ESI/MS. The ligands were immobilized onto gold electrodes and SPR surfaces using-mercaptoundecanoic acid with glycine as deactivating agent. Two detection mechanisms were tested: (i) metal-enhanced electrochemical detection (MED) and (ii) label-free surface plasmon resonance (SPR) detection. The introduction of phenyl residues and aliphatic side groups to the mannose-containing oligosaccharides produced extremely high affinity for E. coli with detection limit of 1 cfu/mL. The relative selectivity of these ligands for E. coli, Citrobacter freundii, Staphylococcus epidermidis were 100%, 2.6% and 8.6% respectively. The biosensors were validated using spinach leaves at 3.0 cfu/mL. The work provides a generic biosensor for other pathogenic bacteria by enabling multivalent binding, immediate recognition for pathogens as well as inhibition of bacterial growth.
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Affiliation(s)
- Idris Yazgan
- Department of Chemistry, Center for Advanced Sensors & Environmental Systems (CASE), State University of New York at Binghamton, P.O. Box 6000, Binghamton, NY 13902-6000, United States
| | - Naumih M Noah
- Department of Chemistry, Center for Advanced Sensors & Environmental Systems (CASE), State University of New York at Binghamton, P.O. Box 6000, Binghamton, NY 13902-6000, United States
| | - Ousmane Toure
- Department of Chemistry, Center for Advanced Sensors & Environmental Systems (CASE), State University of New York at Binghamton, P.O. Box 6000, Binghamton, NY 13902-6000, United States
| | - Siyi Zhang
- Department of Chemistry, Center for Advanced Sensors & Environmental Systems (CASE), State University of New York at Binghamton, P.O. Box 6000, Binghamton, NY 13902-6000, United States
| | - Omowunmi A Sadik
- Department of Chemistry, Center for Advanced Sensors & Environmental Systems (CASE), State University of New York at Binghamton, P.O. Box 6000, Binghamton, NY 13902-6000, United States.
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32
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Flow cytometry immunodetection and membrane integrity assessment of Escherichia coli O157:H7 in ready-to-eat pasta salad during refrigerated storage. Int J Food Microbiol 2014; 168-169:47-56. [DOI: 10.1016/j.ijfoodmicro.2013.10.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 09/25/2013] [Accepted: 10/21/2013] [Indexed: 11/24/2022]
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33
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Duan N, Wu S, Yu Y, Ma X, Xia Y, Chen X, Huang Y, Wang Z. A dual-color flow cytometry protocol for the simultaneous detection of Vibrio parahaemolyticus and Salmonella typhimurium using aptamer conjugated quantum dots as labels. Anal Chim Acta 2013; 804:151-8. [PMID: 24267076 DOI: 10.1016/j.aca.2013.09.047] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 09/20/2013] [Accepted: 09/22/2013] [Indexed: 11/30/2022]
Abstract
A sensitive, specific method for the collection and detection of pathogenic bacteria was demonstrated using quantum dots (QDs) as a fluorescence marker coupled with aptamers as the molecular recognition element by flow cytometry. The aptamer sequences were selected using a bacterium-based SELEX strategy in our laboratory for Vibrio parahaemolyticus and Salmonella typhimurium that, when applied in this method, allows for the specific recognition of the bacteria from complex mixtures including shrimp samples. Aptamer-modified QDs (QD-apt) were employed to selectively capture and simultaneously detect the target bacteria with high sensitivity using the fluorescence of the labeled QDs. The signal intensity is amplified due to the high photostability of QDs nanoparticles, resulting in improved sensitivity over methods using individual dye-labeled probes. This proposed method is promising for the sensitive detection of other pathogenic bacteria in food stuff if suitable aptamers are chosen. The method may also provide another potential platform for the application of aptamer-conjugated QDs in flow cytometry.
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Affiliation(s)
- Nuo Duan
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
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34
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Rapid enumeration of viable bacterial cells in processed soy products using an automated cell counting system. Food Control 2013. [DOI: 10.1016/j.foodcont.2013.01.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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de Sousa Marques A, Nicácio JTN, Cidral TA, de Melo MCN, de Lima KMG. The use of near infrared spectroscopy and multivariate techniques to differentiate Escherichia coli and Salmonella Enteritidis inoculated into pulp juice. J Microbiol Methods 2013; 93:90-4. [DOI: 10.1016/j.mimet.2013.02.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 02/11/2013] [Accepted: 02/11/2013] [Indexed: 10/27/2022]
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36
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Tokonami S, Nakadoi Y, Takahashi M, Ikemizu M, Kadoma T, Saimatsu K, Dung LQ, Shiigi H, Nagaoka T. Label-Free and Selective Bacteria Detection Using a Film with Transferred Bacterial Configuration. Anal Chem 2013; 85:4925-9. [DOI: 10.1021/ac3034618] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shiho Tokonami
- Nanoscience and Nanotechnology Research Center, Research Organization
for the 21st Century, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai 599-8570, Japan
| | - Yu Nakadoi
- Nanoscience and Nanotechnology Research Center, Research Organization
for the 21st Century, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai 599-8570, Japan
| | - Mari Takahashi
- Sharp Corporation, 3-1-72, Kitakamei-cho, Yao 581-8585, Japan
| | - Mugihei Ikemizu
- Sharp Corporation, 3-1-72, Kitakamei-cho, Yao 581-8585, Japan
| | - Tetsuya Kadoma
- Sharp Corporation, 3-1-72, Kitakamei-cho, Yao 581-8585, Japan
| | - Kenta Saimatsu
- Department of Applied Chemistry, Graduate School
of Engineering, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai 599-8570, Japan
| | - Le Quynh Dung
- Department of Applied Chemistry, Graduate School
of Engineering, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai 599-8570, Japan
| | - Hiroshi Shiigi
- Department of Applied Chemistry, Graduate School
of Engineering, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai 599-8570, Japan
| | - Tsutomu Nagaoka
- Department of Applied Chemistry, Graduate School
of Engineering, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai 599-8570, Japan
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37
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Yamaguchi N, Kitaguchi A, Nasu M. Selective enumeration of viable Enterobacteriaceae and Pseudomonas spp. in milk within 7h by multicolor fluorescence in situ hybridization following microcolony formation. J Biosci Bioeng 2012; 113:746-50. [DOI: 10.1016/j.jbiosc.2012.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 01/11/2012] [Accepted: 01/12/2012] [Indexed: 11/16/2022]
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38
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Wang J, Gao J, Liu D, Han D, Wang Z. Phenylboronic acid functionalized gold nanoparticles for highly sensitive detection of Staphylococcus aureus. NANOSCALE 2012; 4:451-4. [PMID: 22159893 DOI: 10.1039/c2nr11657j] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Herein, we report a phenylboronic acid functionalized gold nanoparticle (GNP)-based colorimetric assay for rapid detection of Staphylococcus aureus (S. aureus) with high sensitivity. In this approach, GNPs can bind to S. aureus by the reaction of phenylboronic acid with the cis-diol configuration in glycans on the bacterial surface, providing a colorimetric readout of the binding event. Using this strategy, we have been able to quantify S. aureus at a concentration of 50 cells per mL (three times the standard deviation divided by the slope of the working curve) in aqueous solution.
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Affiliation(s)
- Jine Wang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China
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39
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TSUMURA K, TSUBOI S. Rapid Enumeration of Microbial Cells in Solubilized Soymilk Using an Automatic Cell Counting System with LED Illumination. FOOD SCIENCE AND TECHNOLOGY RESEARCH 2012. [DOI: 10.3136/fstr.18.183] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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40
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Rapid detection of Staphylococcus aureus via a sensitive DNA hybridization assay based on a long-lifetime luminescent europium marker. Mikrochim Acta 2011. [DOI: 10.1007/s00604-011-0654-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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41
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Wang A, Lin B, Sleep BE, Liss SN. The impact of biofilm growth on transport of Escherichia coli O157:H7 in sand. GROUND WATER 2011; 49:20-31. [PMID: 20236334 DOI: 10.1111/j.1745-6584.2010.00690.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Understanding the transport behavior, survival, and persistence of pathogens such as Escherichia coli O157:H7 in the subsurface is essential to protection of public health. In this study, the transport of E. coli O157:H7 in a two-dimensional bench-scale sand aquifer system, hereafter referred to as the sandbox, was investigated, with a focus on the impact of biofilm development on E. coli retention and survival. Biofilm growth was initiated through flushing with unsterilized groundwater and addition of glucose, nitrate, and phosphate. Retention of E. coli from an injection test in clean sand, prior to promotion of biofilm growth, was approximately 9%. Subsequent to biofilm growth, 47% of injected E. coli cells were retained under similar flow conditions. After 10 d of no flow, sterile water was flushed through the biofouled sandbox and substantial concentrations (up to 1.5 × 10(5) cells/mL) of E. coli were measured in the effluent indicating that E. coli had survived the starvation period. Confocal laser scanning microscopy revealed that E. coli were located not only on the surface but also within the biofilm. Imposition of starvation conditions resulted in biofilm sloughing and possible mobilization of biofilm-associated E. coli.
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Affiliation(s)
- Aimin Wang
- Department of Civil Engineering, University of Toronto, 35 St. George St., Toronto, Ontario, Canada
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42
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Rapid, semiautomated quantification of bacterial cells in freshwater by using a microfluidic device for on-chip staining and counting. Appl Environ Microbiol 2010; 77:1536-9. [PMID: 21169431 DOI: 10.1128/aem.01765-10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A microfluidic device-based system for the rapid and semiautomated counting of bacteria in freshwater was fabricated and examined. Bacteria in groundwater and in potable water, as well as starved Escherichia coli O157:H7 spiked in pond water, were able to be on-chip stained and enumerated within 1 h using this system.
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43
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Response to Questions Posed by the Food Safety and Inspection Service Regarding Determination of the Most Appropriate Technologies for the Food Safety and Inspection Service To Adopt in Performing Routine and Baseline Microbiological Analyses†,‡. J Food Prot 2010; 73:1160-200. [DOI: 10.4315/0362-028x-73.6.1160] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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44
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Donofrio RS, Bestervelt LL, Saha R, Bagley ST. Quantitative real-time PCR and fluorescence in situ hybridization approaches for enumerating Brevundimonas diminuta in drinking water. J Ind Microbiol Biotechnol 2010; 37:909-18. [DOI: 10.1007/s10295-010-0738-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Accepted: 04/28/2010] [Indexed: 11/30/2022]
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45
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Temur E, Boyacı İH, Tamer U, Unsal H, Aydogan N. A highly sensitive detection platform based on surface-enhanced Raman scattering for Escherichia coli enumeration. Anal Bioanal Chem 2010; 397:1595-604. [DOI: 10.1007/s00216-010-3676-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 03/22/2010] [Accepted: 03/22/2010] [Indexed: 11/29/2022]
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46
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Yim PB, Clarke ML, McKinstry M, De Paoli Lacerda SH, Pease LF, Dobrovolskaia MA, Kang H, Read TD, Sozhamannan S, Hwang J. Quantitative characterization of quantum dot-labeled lambda phage forEscherichia colidetection. Biotechnol Bioeng 2009; 104:1059-67. [DOI: 10.1002/bit.22488] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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47
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Ikeda M, Yamaguchi N, Nasu M. Rapid On-chip flow Cytometric Detection of Listeria monocytogenes in Milk. ACTA ACUST UNITED AC 2009. [DOI: 10.1248/jhs.55.851] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Masafumi Ikeda
- Environmental Science and Microbiology, Graduate School of Pharmaceutical Sciences, Osaka University
| | - Nobuyasu Yamaguchi
- Environmental Science and Microbiology, Graduate School of Pharmaceutical Sciences, Osaka University
| | - Masao Nasu
- Environmental Science and Microbiology, Graduate School of Pharmaceutical Sciences, Osaka University
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48
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Determination of viable Escherichia coli using antibody-coated paramagnetic beads with fluorescence detection. Anal Bioanal Chem 2008; 393:949-56. [DOI: 10.1007/s00216-008-2531-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 11/12/2008] [Accepted: 11/18/2008] [Indexed: 11/26/2022]
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49
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Qin D, He X, Wang K, Tan W. Using fluorescent nanoparticles and SYBR Green I based two-color flow cytometry to determine Mycobacterium tuberculosis avoiding false positives. Biosens Bioelectron 2008; 24:626-31. [DOI: 10.1016/j.bios.2008.06.023] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 05/06/2008] [Accepted: 06/04/2008] [Indexed: 11/15/2022]
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50
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Cronin UP, Wilkinson MG. Physiological response of Bacillus cereus vegetative cells to simulated food processing treatments. J Food Prot 2008; 71:2168-76. [PMID: 19044257 DOI: 10.4315/0362-028x-71.11.2168] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Vegetative cells of the spore-former Bacillus cereus were exposed to a number of treatments commonly used in commercial food preparation or during equipment cleaning and decontamination. Treated suspensions were then analyzed for reductions (CFU per milliliter) by plate counting and changes in levels of ATP and ADP released from cells with a bioluminescence-based assay. With the use of flow cytometry (FCM), the physiological status of individual cells before and after exposure to treatments was determined by staining of control and treated cells with three pairs of physiological dyes (SYTO 9/propidium iodide, carboxyfluorescein diacetate/Hoechst 33342, and C12-resazurin/SYTOX Green). Good agreement was found between plate counting and FCM. In general, treatments giving rise to the highest count reductions also had the greatest effects on cell membrane permeability (measured with the use of propidium iodide or SYTOX Green), esterase activity (measured with carboxyfluorescein diacetate), or redox activity (C12-resazurin). FCM data demonstrated the extent of heterogeneity of vegetative cell responses to treatments in, for example, the treatment with 5% H2O2, which caused a 6-log reduction in which approximately 95% of the population was composed of membrane-damaged cells (as reflected by their permeability to SYTOX Green), whereas in treatment with 0.09% (wt/vol) potassium sorbate, which caused only a 1-log reduction, not more than 40% of cells were membrane damaged. The approaches described in this work can be applied to gain a greater understanding of bacterial responses to food control measures, generate more accurate inactivation models, or screen novel prospective food control measures.
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Affiliation(s)
- Ultan P Cronin
- Department of Life Sciences, University of Limerick, Castletroy, County Limerick, Ireland
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