154 results on '"microbiological methods"'
Search Results
2. Methods for studying microbial acid stress responses: from molecules to populations.
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Atasoy, Merve, Bartkova, Simona, Çetecioğlu-Gürol, Zeynep, P Mira, Nuno, O'Byrne, Conor, Pérez-Rodríguez, Fernando, Possas, Aricia, Scheler, Ott, Sedláková-Kaduková, Jana, Sinčák, Mirka, Steiger, Matthias, Ziv, Carmit, and Lund, Peter A
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BIOREMEDIATION , *JOB stress , *FOOD industry , *SCIENTIFIC community , *MICROORGANISMS - Abstract
The study of how micro-organisms detect and respond to different stresses has a long history of producing fundamental biological insights while being simultaneously of significance in many applied microbiological fields including infection, food and drink manufacture, and industrial and environmental biotechnology. This is well-illustrated by the large body of work on acid stress. Numerous different methods have been used to understand the impacts of low pH on growth and survival of micro-organisms, ranging from studies of single cells to large and heterogeneous populations, from the molecular or biophysical to the computational, and from well-understood model organisms to poorly defined and complex microbial consortia. Much is to be gained from an increased general awareness of these methods, and so the present review looks at examples of the different methods that have been used to study acid resistance, acid tolerance, and acid stress responses, and the insights they can lead to, as well as some of the problems involved in using them. We hope this will be of interest both within and well beyond the acid stress research community. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Optimized methods for the targeted surveillance of extended-spectrum beta-lactamase-producing Escherichia coli in human stool
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Sarah Gallichan, Sally Forrest, Esther Picton-Barlow, Claudia McKeown, Maria Moore, Eva Heinz, Nicholas A. Feasey, Joseph M. Lewis, and Fabrice E. Graf
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molecular epidemiology ,antimicrobial resistance ,transmission ,surveillance ,microbiological methods ,DNA extraction ,Microbiology ,QR1-502 - Abstract
ABSTRACT Understanding transmission pathways of important opportunistic, drug-resistant pathogens, such as extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, is essential to implementing targeted prevention strategies to interrupt transmission and reduce the number of infections. To link transmission of ESBL-producing E. coli (ESBL-EC) between two sources, single-nucleotide resolution of E. coli strains, as well as E. coli diversity within and between samples, is required. However, the microbiological methods to best track these pathogens are unclear. Here, we compared different steps in the microbiological workflow to determine the impact different pre-enrichment broths, pre-enrichment incubation times, selection in pre-enrichment, selective plating, and DNA extraction methods had on recovering ESBL-EC from human stool samples, with the aim to acquire high-quality DNA for sequencing and genomic epidemiology. We demonstrate that using a 4-h pre-enrichment in Buffered Peptone Water, plating on cefotaxime-supplemented MacConkey agar and extracting DNA using Lucigen MasterPure DNA Purification kit improves the recovery of ESBL-EC from human stool and produced high-quality DNA for whole-genome sequencing. We conclude that our optimized workflow can be applied for single-nucleotide variant analysis of an ESBL-EC from stool.IMPORTANCEDrug-resistant infections are increasingly difficult to treat with antibiotics. Preventing infections is thus highly beneficial. To do this, we need to understand how drug-resistant bacteria spread to take action to stop infection and transmission. This requires us to accurately trace these bacteria between different sources. In this study, we compared different laboratory methods to see which worked best for detecting extended-spectrum beta-lactamase (ESBL)-producing E. coli, a common cause of urinary tract or bloodstream infections, from human stool samples. We found that enriching stool in a nutrient broth for 4 h, then plating the bacterial suspension on antibiotic-selective MacConkey agar, and finally extracting DNA from the bacteria using a specific DNA purification kit resulted in improved recovery of ESBL E. coli and high-quality DNA. Sequencing multiple isolates from stool allowed us to distinguish unambiguously and at high resolution between different variants of ESBL E. coli present in stool.
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- 2025
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4. Peculiarities of natural honey classification in the course of forensic commodity examination
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P. P. Kanivets
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classification of natural honey ,forensic commodity examination ,quality ,instrumental methods ,microbiological methods ,defects of natural honey. ,Law in general. Comparative and uniform law. Jurisprudence ,K1-7720 - Abstract
The main identification tasks of the commodity expertise of natural honey are to establish its authenticity, quality and assessment of compliance with the requirements of standards. To achieve these objectives, experts conduct a number of analyses and determinations, including determining the authenticity of honey, determining the botanical and geographical origin of honey, determining the composition and quality, determining compliance with quality standards, and determining the content of impurities and antioxidants. By carrying out these identification tasks, the examination helps ensure quality and safety of honey on the market and protects consumer rights. Defects in honey can occur for a variety of reasons and are usually the result of deficiencies in honey production, storage or transportation. The scientific article describes the peculiarities of classification of natural honey during forensic commodity examination, reveals the methodological aspects of forensic commodity examination of honey, identifies theoretical and practical problems of commodity research of honey, reveals the commodity characteristics of honey and its defects, instrumental methods of honey examination, in particular gas and liquid chromatography, spectroscopy, solid-phase microextraction, describes the main microbiological methods that can be used in the study of honey, offers a systematisation of information data on the peculiarities of forensic examination of honey with regard to its characteristic defects. The stages of conducting a forensic commodity examination of honey are presented. Recommendations regarding honey quality assessment for expert organizations and consumers are given.
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- 2023
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5. Inactivating and damaging properties of the disinfectant 'MultiDez' when exposed to bacteria and spores
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Vladimir Nikolaevich Gerasimov, Lyudmila Aleksandrovna Kraeva, Dmitrij Anatol'evich Svetlov, Ajgul’ Ravilovna Gajtrafimova, Elena Vladimirovna Bystrova, Sergej Anatol'evich Kotov, and Daniil Dmitrievich Svetlov
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Disinfectant ,Microbiological methods ,Electron microscopic research methods ,Ultrastructure of cells ,Bacterial spores ,Ultrastructure of spores ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Disinfectants play a crucial role in controlling the spread of infectious diseases caused by bacteria and spore-forming organisms. Bacteria and spores can persist on surfaces and in the environment for extended periods, posing a significant risk to public health. Disinfectants are designed to inactivate or kill these microorganisms by disrupting their cellular structures and functions. Effective disinfectants are essential for preventing the spread of infectious diseases in hospitals, laboratories, food processing facilities, and other settings where the risk of contamination is high.This study evaluated the effectiveness of a disinfectant called “MultiDez” on Y.pestis bacteria and Bacillus anthracis spores using microbiological and electron microscopic methods. Results showed that after exposure to a 0.5 % solution of the disinfectant, the death of all Y.pestis bacteria was achieved after 90 min, while the death of Bacillus anthracis spores was achieved after 240 min. Electron microscopy revealed that the disinfectant caused complete destruction of both bacterial cells and spores by enveloping their outer surfaces with polymer molecules, disrupting the structure and function of their membranes, and destroying their cytoplasm and nucleode. The mechanism of action of the disinfectant on bacteria and spores involved different processes, with the disinfectant causing rapid hydration of dehydrated spores and blocking the functions of spore membranes in the case of bacterial spores.
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- 2023
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6. Design and Initial Evaluation of a Novel Oral Hygiene Technology for a Special Needs Population: A New Way to Clean.
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Strickland, Maxine, Mills, Steven, Dasari, Bhargavi, Markowitz, Kenneth, and Cugini, Carla
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ORAL hygiene ,TOOTHBRUSHES ,FLUOROSIS - Abstract
9.4 million People have swallowing problems in the US. In special needs populations, routine oral hygiene procedures such as tooth brushing can result in aspiration of microbial laden fluids leading to a significant systemic challenge. Aspiration may lead to pneumonia in susceptible populations. These circumstances indicate the need for innovative approaches to oral hygiene for special needs, convalescent, the elderly populations, and young children learning to brush who can ingest excess fluoride which causes mottled enamel. Methods include describing some of the design considerations of the new prototype fabrication and microbiological evaluation of this new device, as well a comparison study of the versions 2 and 3 of the oral care device. Results concluded that version 3.0 regarding patient ease of use was better in comparison to version 2, which was the major difference, and 90% in both groups said they would recommend the new toothbrush. In the microbiological evaluation no growth was seen on any plates containing samples from either the experimental or the control after 48 h of incubation. [ABSTRACT FROM AUTHOR]
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- 2023
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7. Design and Initial Evaluation of a Novel Oral Hygiene Technology for a Special Needs Population: A New Way to Clean
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Maxine Strickland, Steven Mills, Bhargavi Dasari, Kenneth Markowitz, and Carla Cugini
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powered toothbrush ,oral hygiene ,microbiological methods ,Dentistry ,RK1-715 - Abstract
9.4 million People have swallowing problems in the US. In special needs populations, routine oral hygiene procedures such as tooth brushing can result in aspiration of microbial laden fluids leading to a significant systemic challenge. Aspiration may lead to pneumonia in susceptible populations. These circumstances indicate the need for innovative approaches to oral hygiene for special needs, convalescent, the elderly populations, and young children learning to brush who can ingest excess fluoride which causes mottled enamel. Methods include describing some of the design considerations of the new prototype fabrication and microbiological evaluation of this new device, as well a comparison study of the versions 2 and 3 of the oral care device. Results concluded that version 3.0 regarding patient ease of use was better in comparison to version 2, which was the major difference, and 90% in both groups said they would recommend the new toothbrush. In the microbiological evaluation no growth was seen on any plates containing samples from either the experimental or the control after 48 h of incubation.
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- 2023
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8. Assessment Of Vaginal Infections In Pregnant Women.
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Patange, R. P., Kshirsagar, N. S., patil, Shital, and vhawal, Shilpa
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PREGNANT women , *GRAM'S stain , *VAGINITIS , *BACTERIAL vaginitis , *INFECTION - Abstract
Background: Vaginitis is inflammation of the vagina. Vulvovaginitis, is an inflammation of the vagina and vulva. Infection can result in discharge, itching and pain. The present study was conducted to assess vaginal infections in pregnant women. Materials & Methods: 76 pregnant women reporting to Obstetric & Gynaecology department for vaginal infection. A detailed obstetric examination was carried out as well. Per speculum examination was carried out and the vaginal mucosa was inspected for the presence of erythema, lesions, and discharge. Vaginal and cervical swabs samples were obtained and sent to microbiology laboratory. Results: There were 10 in first trimester, 26 in second and 40 in third trimester. The difference was significant (P< 0.05). Clue cells in wet mount was positive in 8 and negative in 68, Nugent's score >7 was positive in 12 and negative in 64. Amsel's criteria was positive in 14 and negative in 62. The difference was significant (P< 0.05). Gram's stain was positive in 5 and negative in 71 and culture was positive in 11 and negative in 65. The difference was significant (P< 0.05). Conclusion: Bacterial vaginosis was seen in 14 and candidiasis in 11 cases. Diagnosis of vaginal infections was done using both clinical and microbiological methods. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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9. Methods for Intensifying Biogas Production from Waste: A Scientometric Review of Cavitation and Electrolysis Treatments.
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Chubur, Viktoriia, Danylov, Dmytro, Chernysh, Yelizaveta, Plyatsuk, Leonid, Shtepa, Vladimir, Haneklaus, Nils, and Roubik, Hynek
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BIOGAS production ,ELECTROLYSIS ,CAVITATION ,SEWAGE sludge digestion ,ANAEROBIC digestion ,BIOMATERIALS ,ANAEROBIC bacteria - Abstract
This article presents future trends in research using microbiological methods to intensify bioprocesses for biogas production. The pretreatment by combinations of physical and chemical methods, such as cavitation and electrolysis, is considered. The approach of the article involved reviewing the residual area on the intensification technologies of anaerobic digestion with current methods to improve the quality and quantity of biogas. The most valuable reported positive results of the pretreatment of biological raw materials in the cavitation process were reviewed and are presented here. A model of the effect of electrolysis on the species diversity of bacteria in anaerobic digestion was developed, and changes in the dominance of the ecological and trophic systems were revealed on the basis of previous studies. The stimulating effect on biogas yield, reduction in the stabilization period of the reactor, and inactivation of microorganisms at lower temperatures is associated with different pretreatment methods that intensify anaerobic digestion. More research is recommended to focus on the electrolysis treatment of different types of waste and their ratios with optimization of regime parameters, as well as in combination with other pretreatments to produce biomethane and biohydrogen in larger quantities and in better qualities. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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10. Modern trends in identification of causative agents in infective endocarditis
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E. O. Kotova, E. A. Domonova, Zh. D. Kobalava, J. L. Karaulova, A. S. Pisaryuk, A. V. Balatskiy, and V. G. Akimkin
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culture negative infective endocarditis ,microbiological methods ,maldi-tof ms ,real-time pcr ,microbiologistic ,Therapeutics. Pharmacology ,RM1-950 ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Advances in the diagnosis and treatment of patients with infectious endocarditis are limited by the high frequency of cases with an unknown etiology and imperfection of microbiological (cultural) methods. To overcome these problems new approaches to the identification of infectious endocarditis pathogens were introduced, which allowed achieving certain positive results. However, it should be noted that despite the wide variety of diagnostic tools currently used, there is no ideal method for etiological laboratory diagnosis of infectious endocarditis. The article discusses the features and place of immunochemical, molecular biological (MALDI-TOF MS, real-time PCR, sequencing, in situ fluorescence hybridization, metagenomic methods, etc.), immunohistochemical methods, and their advantages and limitations.
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- 2021
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11. RESEARCH ON APPLICATION OF GEOLOGICAL MICROBIOLOGY TECHNOLOGY IN WUMAYING AREA CHINA.
- Author
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Sheng Yang
- Abstract
The Wumaying Fault Zone is located in the northeast of the Dengmingsi Fault Tectonic Zone in China. A large number of faults are developed in this area, most of them are distributed in nearly east-west and north-east directions, and a few are distributed along the northwest or north-south direction. In this study, the oil and gas microbial exploration technology combined with seismic data was used to deploy the MPOG survey network. On this basis, the natural gas distribution range and its reserves in the study area were analyzed. The results show that the microbial natural gas anomaly in this study area is relatively weak, and it is a background value. This reflects that the natural gas distribution area in this study area is small and the reserves are limited. In this study area, a total of 8 microbial abnormalities were displayed, and the abnormal areas were graded. Through the research results of microbial anomalies in this study area, it is recommended that the structural interpretation of Wumaying area should focus on the study of secondary faults, especially the secondary faults along the direction of W19-W21, so as to identify lithologic-fault block traps. Along the direction of W19-W21, multiple oil-bearing fault blocks are on the same oil and gas migration channel and have strong correlation. It is recommended to design an overall evaluation and development plan. The only abnormally high value of microbial gas in the study area is in the W31 block, and the remaining oil potential of the W28 block needs to be further determined. The lithology-fault block traps and hydrocarbon-bearing conditions of the two blocks in the south, the two blocks in the north, and the two blocks in the west of the study area need to be further confirmed to increase the reserves in the area. [ABSTRACT FROM AUTHOR]
- Published
- 2022
12. Assessing Viability and Stress Tolerance of Probiotics—A Review.
- Author
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Wendel, Ulrika
- Subjects
PROBIOTICS ,BACTERIAL cells ,GASTROINTESTINAL system ,QUALITY control - Abstract
The interest in probiotics has increased rapidly the latest years together with the global market for probiotic products. Consequently, establishing reliable microbiological methods for assuring the presence of a certain number of viable microorganisms in probiotic products has become increasingly important. To assure adequate numbers of viable cells, authorities are enquiring for information on viability rates within a certain shelf-life in colony forming units (CFU). This information is obtained from plate count enumeration, a method that enables detection of bacterial cells based on their ability to replicate. Although performing plate count enumeration is one manner of assessing viability, cells can still be viable without possessing the ability to replicate. Thus, to properly assess probiotic viability, further analysis of a broader group of characteristics using several types of methods is proposed. In addition to viability, it is crucial to identify how well the cells in a probiotic product can survive in the gastrointestinal tract (GIT) and thus be able to mediate the desired health benefit while passing through the human body. A broad spectrum of different assay designs for assessing probiotic gastric tolerance have been used in research and quality control. However, the absence of any consensus on how to assess these qualities makes it difficult to compare between laboratories and to translate the results into in vivo tolerance. This review presents and discusses the complexity of assuring that a probiotic is suitable for beneficial consumption. It summarizes the information that can be subtracted from the currently available methods for assessment of viability and stress tolerance of a probiotic, hereby altogether defined as "activity." Strengths and limitations of the different methods are presented together with favorable method combinations. Finally, the importance of choosing a set of analyses that reveals the necessary aspects of probiotic activity for a certain product or application is emphasized. [ABSTRACT FROM AUTHOR]
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- 2022
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13. Methods for Intensifying Biogas Production from Waste: A Scientometric Review of Cavitation and Electrolysis Treatments
- Author
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Viktoriia Chubur, Dmytro Danylov, Yelizaveta Chernysh, Leonid Plyatsuk, Vladimir Shtepa, Nils Haneklaus, and Hynek Roubik
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bioprocesses ,biogas production ,cavitation ,electrolysis ,microbiological methods ,Fermentation industries. Beverages. Alcohol ,TP500-660 - Abstract
This article presents future trends in research using microbiological methods to intensify bioprocesses for biogas production. The pretreatment by combinations of physical and chemical methods, such as cavitation and electrolysis, is considered. The approach of the article involved reviewing the residual area on the intensification technologies of anaerobic digestion with current methods to improve the quality and quantity of biogas. The most valuable reported positive results of the pretreatment of biological raw materials in the cavitation process were reviewed and are presented here. A model of the effect of electrolysis on the species diversity of bacteria in anaerobic digestion was developed, and changes in the dominance of the ecological and trophic systems were revealed on the basis of previous studies. The stimulating effect on biogas yield, reduction in the stabilization period of the reactor, and inactivation of microorganisms at lower temperatures is associated with different pretreatment methods that intensify anaerobic digestion. More research is recommended to focus on the electrolysis treatment of different types of waste and their ratios with optimization of regime parameters, as well as in combination with other pretreatments to produce biomethane and biohydrogen in larger quantities and in better qualities.
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- 2022
- Full Text
- View/download PDF
14. 在场拭子法检测猪组织中抗生素残留.
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黄林丽, 欧阳子程, 魏煮, 王梓莹, 黄思营, 张悦彤, 蔡文静, and 何庆华
- Abstract
Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
15. Aptamer-based approaches for the detection of waterborne pathogens
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Vishwakarma, Archana, Lal, Roshni, and Ramya, Mohandass
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- 2021
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16. Validation of standard method EN ISO 11290 - Part 1 - Detection of Listeria monocytogenes in food.
- Author
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Gnanou Besse, Nathalie, Lombard, Bertrand, Guillier, Laurent, François, Danièle, Romero, Karol, Pierru, Sylvie, Bouhier, Laurence, and Rollier, Patricia
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LISTERIA monocytogenes , *SALMON , *DRIED milk , *FOOD , *VEGETABLES - Abstract
Abstract The reference method for the detection and enumeration of L. monocytogenes in food (Standards EN ISO 11290-1&2) has been validated by inter-laboratory studies in the frame of the Mandate M381 from European Commission to CEN. In this paper, the collaborative studies led in 2013 on 5 matrices (cold-smoked salmon, milk powdered infant food formula, vegetables, environment, and cheese) to validate the recently revised Standard EN ISO 11290-Part 1 are reported. According to the results obtained, the revised Standard EN ISO 11290-1 can be considered as a good method for the detection of L. monocytogenes in foods and food processing environments, in particular for the matrices included in the study. According to the matrices, the sensitivity rate varied from 91.1% to 100%, and the specificity rate varied from 97.6% to 100%. Positive samples were most often detected after 24 h half-Fraser enrichment. [ABSTRACT FROM AUTHOR]
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- 2019
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17. Validation of standard method EN ISO 11290 - Part 2 for the enumeration of Listeria monocytogenes in food.
- Author
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Rollier, Patricia, Lombard, Bertrand, Guillier, Laurent, François, Danièle, Romero, Karol, Pierru, Sylvie, Bouhier, Laurence, and Gnanou Besse, Nathalie
- Subjects
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LISTERIA monocytogenes , *VEGETABLES , *FOOD industry , *SALMON - Abstract
Abstract The reference method for the detection and enumeration of L. monocytogenes in food (Standards EN ISO 11290-1&2) have been validated by inter-laboratory studies in the frame of the Mandate M381 from European Commission to CEN. In this paper, the inter-laboratory studies led in 2013 on 5 matrices (cold-smoked salmon, milk powdered infant food formula, vegetables, environment, and cheese) to validate Standard EN ISO 11290-2 are reported. According to the results obtained, the method of the revised Standard EN ISO 11290-2 can be considered as a good method for the enumeration of L. monocytogenes in foods and food processing environment, in particular for the matrices included in the study. Values of repeatability and reproducibility standard deviations can be considered satisfactory for this type of method with a confirmation stage, since most of them were below 0.3 log 10 , also at low levels, close to the regulatory limit of 100 CFU/g. [ABSTRACT FROM AUTHOR]
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- 2019
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18. Improved Recovery of Stressed Listeria monocytogenes from Frozen Foods.
- Author
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McLennon, Julie, Borza, Antonela, Eisebraun, Mikaela, and Garduño, Rafael
- Abstract
The Canadian reference method for the enumeration of Listeria monocytogenes (Health Canada method MFLP-74) was modified by the addition of a layer of non-selective tryptone soy agar (TSA) to the Oxford, Palcam, and (or) Rapid'L.mono selective agars, to improve the recovery of stressed L. monocytogenes from frozen foods. The performance of the standard selective agars versus the selective agars with an additional TSA agar layer (TAL agars) showed that for each of the frozen food items tested (vegetables, shrimp and meatballs), as well as for all data combined, L. monocytogenes counts were significantly higher (up to 20% higher) in TAL agars in relation to the standard agars ( p < 0.0001, α = 0.05). A selectivity assessment showed that the 50 inclusivity L. monocytogenes strains tested produced true positive reactions on the TAL agars, and the 30 exclusivity bacterial strains tested produced true negative results on the TAL agars, indicating that the specificity of the selective agars was not altered by the additional non-selective TSA layer. In light of the 2016 Listeria outbreak linked to frozen fruits and vegetables in the USA, the results of this method investigation seem to be timely and particularly important for the regulatory testing of frozen foods. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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19. Ecological Approach to Evaluate Effects of Chemical Pollutants in Soil and Groundwater
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Filip, Zdenek, Demnerova, Katerina, Simeonov, Lubomir I., editor, and Hassanien, Mahmoud A., editor
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- 2009
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20. Detection and Identification of Bacillus anthracis: From Conventional to Molecular Microbiology Methods
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Aleksandra A. Zasada
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bacillus anthracis ,detection ,identification ,rapid tests ,microbiological methods ,molecular microbiology methods ,biosensors ,molecular markers ,Biology (General) ,QH301-705.5 - Abstract
Rapid and reliable identification of Bacillus anthracis is of great importance, especially in the event of suspected deliberate release of anthrax spores. However, the identification of B. anthracis is challenging due to its high similarity to closely related species. Since Amerithrax in 2001, a lot of effort has been made to develop rapid methods for detection and identification of this microorganism with special focus on easy-to-perform rapid tests for first-line responders. This article presents an overview of the evolution of B. anthracis identification methods from the time of the first description of the microorganism until the present day.
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- 2020
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21. Bronchoscopic biopsies with radial endobronchial ultrasonographic navigation in the diagnosis of tuberculosis and mycobacteriosis in patients with peripheral lung masses
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I. Yu. Shabalina, A. S. Zaytseva, A. I. Popova, E. E. Larionova, O. V. Lovacheva, and A. E. Ergeshov
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Tuberculosis ,bronchoscopy ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Diseases of the respiratory system ,0302 clinical medicine ,Bronchoscopy ,Pulmonary tuberculosis ,Biopsy ,medicine ,navigation ,rebus ,Lung ,medicine.diagnostic_test ,RC705-779 ,business.industry ,mycobacteriosis ,Transbronchial lung biopsy ,microbiological methods ,General Medicine ,medicine.disease ,Bronchoalveolar lavage ,medicine.anatomical_structure ,030228 respiratory system ,tuberculosis ,bronchobiopsy ,Etiology ,business ,Nuclear medicine - Abstract
The objective of the study: to evaluate the effectiveness of diagnosis of tuberculosis and mycobacteriosis in bronchobiopsy specimens obtained during navigation by radial endobronchial ultrasonography (rEBUS) in patients with peripheral lung lesions without bacterial excretion.Subjects and methods. A retrospective analysis of the diagnostic effectiveness of bronchoscopic examination with biopsies was carried out in 179 patients (75 men and 104 women) suffering from pulmonary tuberculosis or mycobacteriosis without bacterial excretion; peripheral lung lesions had been visualized by computed tomography (CT). The patients were divided into two groups: 93 underwent bronchoscopy with biopsies with rEBUS navigation, 86 underwent bronchoscopy with classical biopsies and preliminary CT navigation. Each patient underwent multiple biopsies, at least one fluid biopsy (bronchoalveolar lavage or bronchial lavage), and one tissue biopsy (transbronchial lung biopsy or brush biopsy). Specimens collected by all types of bronchobiopsy were sent for microbiological and cytological tests, specimens of pulmonary transbronchial biopsy were additionally sent for histological examination.Results. The diagnosis of tuberculosis was verified by bronchobiopsy in 106 (67.5%) of 158 patients with tuberculosis, but statistically significantly more often in the group with rEBUS navigation versus the group without it – 81.9% (68/83) versus 50.7% (38/75), respectively (pχ2 < 0.01). The diagnosis of non-tuberculous mycobacteriosis was verified by bronchobiopsy in 13 (61.9%) of 21 patients, in the group with rEBUS navigation – in 80.0% (8/10) patients, in the group without it – in 45.5% (5/11) (pφ > 0.05). The use of rEBUS navigation while collecting bronchobiopsy specimens made it possible to increase the etiological verification of tuberculosis using the following microbiological methods: microscopy – from 14.7 to 49.4% (pχ2 < 0.01), molecular genetic – from 41.3 to 72.3% ( pχ2 < 0.01), culture (Bactec MGIT960) – from 44.0 to 67.5% (pχ2 < 0.01) The greatest enhancement of diagnostic effectiveness was achieved in the specimens of bronchoalveolar lavage and bronchial lavage – from 33.3 to 71.1% (pχ2 < 0.01) and in brush biopsy specimens – from 25.6 to 57.6% (pχ2 < 0.01).
- Published
- 2021
22. Validation of PhageDx™ Cronobacter Assay for the Identification of Cronobacter Spp. in Powdered Infant Formula: AOAC Performance Tested MethodSM 051803
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Jessica Stach, Wendy Hahn, Stephen Erickson, Minh Mindy Bao Nguyen, and José J. Gil
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AcademicSubjects/SCI01140 ,AcademicSubjects/SCI01060 ,Stability test ,AcademicSubjects/SCI00030 ,Food Contamination ,AcademicSubjects/SCI01180 ,Analytical Chemistry ,Humans ,Environmental Chemistry ,Food science ,Cronobacter ,Luciferase reporter gene ,Pharmacology ,Microbiological Methods ,biology ,Significant difference ,Infant ,biology.organism_classification ,Infant Formula ,Infant formula ,Food Microbiology ,Standard protocol ,AcademicSubjects/SCI00980 ,Powders ,Agronomy and Crop Science ,Food Science - Abstract
Background The PhageDx™Cronobacter Assay is based on the infection of Cronobacter spp. by specific bacteriophages and expression of a luciferase reporter gene. Results are generated in as little as 18.5 h for powdered infant formula (PIF). Objective An AOAC Performance Tested MethodsSM (PTM) study was conducted to validate the PhageDx Cronobacter Assay for the detection of Cronobacter in 10, 100, and 300 g milk- and soy-based PIF test portions. Method The performance of the PhageDx method was compared to the ISO 22964:2006/2017 Microbiology of the Food Chain—Horizontal Method for the Detection of Cronobacter spp. and the U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM) Chapter 29 Cronobacter: 2012. Inclusivity/exclusivity, product consistency and stability, and robustness testing also were conducted. Results There was no significant difference between the 10, 100, or 300 g test portions for the milk and soy PIF matrixes between the PhageDx Cronobacter Assay, the ISO 22964:2006/2017, and the FDA BAM Chapter 29 Cronobacter: 2012 methods. The reporter bacteriophages were specific for Cronobacter and infected 75 strains in inclusivity testing. They did not infect 35 non-Cronobacter bacteria in exclusivity testing. Robustness testing showed that the method performed well with specific deviations from the standard protocol. Consistency and stability testing demonstrated that the recombinant phage gave consistent results across three production lots and was stable when stored under appropriate conditions for at least 3 months. Conclusions Work in the submitting and independent laboratories demonstrated that the PhageDx Cronobacter Assay meets the qualifications for PTM status. Highlights The PhageDx Cronobacter Assay is a rapid, simple, and specific test that has shown equivalence to both the FDA BAM and ISO reference methods for detecting Cronobacter spp. in PIF.
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- 2021
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23. Validation of the PhageDx™ Listeria Assay for Detection of Listeria Spp. on Stainless Steel and Ceramic Environmental Surfaces AOAC Performance Tested MethodSM 102005
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Brinna Zimmer, Stephen Erickson, Wendy Hahn, Minh Mindy Bao Nguyen, Dustin Stevens, Henriett Zahn, John Paulson, José J. Gil, and Thai Dong
- Subjects
AcademicSubjects/SCI01140 ,Ceramics ,Stability test ,AcademicSubjects/SCI01060 ,Listeria ,AcademicSubjects/SCI00030 ,medicine.disease_cause ,AcademicSubjects/SCI01180 ,Analytical Chemistry ,Bacteriophage ,Matrix (chemical analysis) ,Listeria monocytogenes ,medicine ,Environmental Chemistry ,Ceramic ,Pharmacology ,Bacteriological Techniques ,Chromatography ,Microbiological Methods ,biology ,Chemistry ,Significant difference ,biology.organism_classification ,Stainless Steel ,visual_art ,visual_art.visual_art_medium ,Standard protocol ,Food Microbiology ,AcademicSubjects/SCI00980 ,Agronomy and Crop Science ,Food Science - Abstract
Background The PhageDx™ Listeria Assay is a simple, specific, and sensitive assay based on the infection of Listeria spp. by selected bacteriophages and the resultant expression of a luciferase reporter gene. Results are generated in as little as 24.5 h for stainless steel and ceramic environmental surfaces. Objective An AOAC Performance Tested MethodsSM (PTM) study was conducted to validate the PhageDx Listeria Assay for the detection of Listeria on stainless steel and ceramic surfaces. Method The performance of the PhageDx method was compared to that of the U.S. Food and Drug Administration (FDA) Bacterial Analytical Manual (BAM) Ch. 10. Inclusivity/exclusivity, product consistency and stability, and robustness testing also were conducted. Results Inclusivity testing demonstrated that the reporter bacteriophages were specific for Listeria ssp. and detected 58/61 Listeria strains tested, including all 34 L. monocytogenes strains. The reporter bacteriophage also was shown to not detect 46/47 non-Listeria bacteria in exclusivity testing. Robustness testing showed that the method performed well with specific deviations from the standard protocol. Consistency and stability testing demonstrated that the recombinant phage gave consistent results across three production lots and was stable when stored under appropriate conditions for at least 6 months. Matrix studies on stainless steel and ceramic surfaces showed that there was no significant difference between the PhageDx Listeria Assay and the FDA/BAM Chapter 10 reference method. Conclusions and Highlights The validation study demonstrates that the PhageDx Listeria Assay is an effective method for the detection of Listeria spp. on stainless steel and ceramic environmental surfaces and meets the qualifications for AOAC PTM status.
- Published
- 2021
24. Promising Areas of Chemical and Microbiological Treatment of Nonferrous and Precious Metal Mineral Resources.
- Author
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Arens, V., Shumilova, L., Fazlullin, M., and Khcheyan, G.
- Subjects
- *
NONFERROUS metal metallurgy , *MICROBIOLOGICAL synthesis , *GEOTECHNICAL engineering , *METALLURGY estimates , *LEACHING - Abstract
The contemporary state and main problems of chemical and microbiological technology for processing mineral resources are analyzed. The main problems are given for the use of technogenic raw material. Results are analyzed for pilot plant work using physicochemical geotechnology for opening up deposits of hard economic minerals. Promising areas are considered for development of technology using achievements of chemistry and microbiology for innovative development of the mining and metallurgical complex in the 21st century. [ABSTRACT FROM AUTHOR]
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- 2018
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25. Confirming the Presence of Legionella pneumophila in Your Water System: A Review of Current Legionella Testing Methods
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Paul J McDermott and James T Walker
- Subjects
AcademicSubjects/SCI01140 ,AcademicSubjects/SCI01060 ,Legionella ,AcademicSubjects/SCI00030 ,010501 environmental sciences ,AcademicSubjects/SCI01180 ,Immunomagnetic separation ,01 natural sciences ,Legionella pneumophila ,System a ,Analytical Chemistry ,Microbiology ,law.invention ,03 medical and health sciences ,law ,medicine ,Humans ,Environmental Chemistry ,Polymerase chain reaction ,0105 earth and related environmental sciences ,Pharmacology ,Colony-forming unit ,0303 health sciences ,Microbiological Methods ,biology ,030306 microbiology ,Drinking Water ,bacterial infections and mycoses ,Multiple species ,biology.organism_classification ,medicine.disease ,respiratory tract diseases ,Legionnaires' disease ,AcademicSubjects/SCI00980 ,Legionnaires' Disease ,Water Microbiology ,Agronomy and Crop Science ,Food Science - Abstract
Legionnaires’ disease has been recognized since 1976 and Legionella pneumophila still accounts for more than 95% of cases. Approaches in countries, including France, suggest that focusing risk reduction specifically on L. pneumophila is an effective strategy, as detecting L. pneumophila has advantages over targeting multiple species of Legionella. In terms of assays, the historically accepted plate culture method takes 10 days for confirmed Legionella spp. results, has variabilities which affect trending and comparisons, requires highly trained personnel to identify colonies on a plate in specialist laboratories, and does not recover viable-but-non-culturable bacteria. PCR is sensitive, specific, provides results in less than 24 h, and determines the presence/absence of Legionella spp. and/or L. pneumophila DNA. Whilst specialist personnel and laboratories are generally required, there are now on-site PCR options, but there is no agreement on comparing genome units to colony forming units and action limits. Immunomagnetic separation assays are culture-independent, detect multiple Legionella species, and results are available in 24 h, with automated processing options. Field-use lateral flow devices provide presence/absence determination of L. pneumophila serogroup 1 where sufficient cells are present, but testing potable waters is problematic. Liquid culture most probable number (MPN) assays provide confirmed L. pneumophila results in 7 days that are equivalent to or exceed plate culture, are robust and reproducible, and can be performed in a variety of laboratory settings. MPN isolates can be obtained for epidemiological investigations. This accessible, non-technical review will be of particular interest to building owners, operators, risk managers, and water safety groups and will enable them to make informed decisions to reduce the risk of L. pneumophila.
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- 2021
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26. Evaluation of sensitivity of modified star protocol microbiological method for beta-lactame antibiotics detection in raw cow milk
- Author
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Borović Branka, Spirić Danka, Velebit Branko, Đorđević Vesna, Lakićević Brankica, Baltić Tatjana, and Spirić Aurelija
- Subjects
milk ,antibiotics ,residue ,microbiological methods ,STAR protocol ,Veterinary medicine ,SF600-1100 - Abstract
Antibiotic residues when present in animal tissues, through food chain, can enter human body, causing allergic reactions or facilitating the development of resistant bacterial strains. In order to determine the presence of antibiotics in animal tissues, it is appropriate to use convenient, reliable and sensitive methods. Microbiological methods applied for the detection of antibiotic residues in primary products of animal origin are based on the sensitivity of specific bacterial strains to a particular group of antibiotics. Regulatives on the amount of pesticides, metals and metalloids and other toxic substances, chemotherapeutics, anabolics and other substances which can be found in food ("Off. Gazette", No. 5/92, 11/92 - corr. and 32/02), state that milk and milk products can be used in commercial purposes only if not contain antibiotics in quantities that can be detected by reference methods. The applied method is modified STAR (Screening test for detection of antibiotics) protocol, regulated by the CRL (Community Reference Laboratory) Fougeres, France, in which the initial validation of the method had been carried out. In accordance with the demands of Regulative Commission EC No657/2002, the sensitivity of modified STAR protocol for beta lactam antibiotics group was examined , that is, there was carried out a contracted validation of the method, which initial validation had been performed at CRL. In a couple of series of experiments, 20 blank samples of raw cow milk originating from animals not treated by antibiotics, had been examined. By the beginning of the experiment samples were stored in a freezer at -20ºC. Samples of raw cow milk enriched by working solutions of seven beta-lactam antibiotics, in order to obtain concentrations at the level of 0.5, 1 and 1.5 MRL (Maximmum Residue Limit) for each given antibiotic (Commission Regulation EC No. 37/2010). For detection of beta-lactam antibiotics, there was used Kundrat agar test with previously inoculated G.stearothermophilus ATCC 10149 strain. Aliquots of 30 _l of working solution at 0.5, 1 and 1.5 MRL concentration level, for each antibiotic, were inflicted on two paper disks placed on inoculated Kundrat agar surface. Petri plates with Kundrat agar previously inoculated with G.stearothermophilus , on which the samples were deposited, were incubated for 12-15h at 55oC. The obtained width of microorganisms growth inhibition zone, that is supposed to be at least 2.0 mm, measured from the disc edge, demonstrated the capability to detect all the tested 7 antibiotics from the beta lactam group at a level below the MRLs. Consequently, this proves that use of this method it is possible to meet the demands of Regulative Commission EC No. 37/2010. [Projekat Ministarstva nauke Republike Srbije, br. III-46009]
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- 2013
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27. Validation of the Reveal® 3-D for Peanut Lateral Flow Test: AOAC Performance Tested MethodSM 111901
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Alexis Vance, Quynh-Nhi Le, Robert Donofrio, Dave Almy, Emily Slenk, Nawal Bakir, Nicole Klass, Benjamin Bastin, and Brooke Roman
- Subjects
Pharmacology ,Residue (complex analysis) ,Microbiological Methods ,Food industry ,Arachis ,010405 organic chemistry ,Chemistry ,business.industry ,010401 analytical chemistry ,Flow method ,food and beverages ,Allergens ,Cross Reactions ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Lateral flow test ,Assay interference ,Environmental Chemistry ,Nuts ,Food preparation ,Food science ,business ,Agronomy and Crop Science ,Food Science - Abstract
Background Reveal® 3-D for Peanut is an immunochromatographic, lateral flow test for qualitative detection of peanut residue in food manufacturing and food preparation settings. The test can detect low ppm levels of peanut in clean-in-place (CIP) rinses and in swabs from environmental surfaces and can serve as a tool in managing allergen risk. Objective The objective of the study was to validate the lateral flow method for detection of peanut in CIP rinses, specifically water, peroxyacetic acid/hydrogen peroxide, and quaternary ammonium compound rinses, and in swabs taken from stainless steel and plastic surfaces. Methods CIP rinses spiked with low levels of peanut were tested, as were surfaces inoculated with peanut. Specificity and assay interference were assessed in testing of food commodities with and without added peanut. Assay robustness and test kit stability and consistency testing were also performed. Results Results demonstrated that the lateral flow test can detect peanut in CIP rinses in the range of 2–4 ppm and in environmental surface swabs in the range of 3–4 µg/100 cm2. Results of specificity testing with 29 common food items showed lack of cross-reactivity, and potential assay interference only from walnut. Data from stability trials supports expiration dating for the kit of up to 23 months post-manufacture. Conclusions and Highlights The lateral flow test is a sensitive, specific, and rapid method for detection of low levels of peanut residue in CIP rinses and environmental samples and can be an important component in a comprehensive allergen risk management program.
- Published
- 2020
28. TRIO Method for Detection of Beta-Lactams, Sulfonamides, and Tetracyclines in Raw Commingled Cows' Milk
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Emily Kalinowski, David Conaway, Lindsey W McRobbie, Robert J. Markovsky, David R. Legg, Janine A Schwartz, Alan C Tran, Mary Bulthaus, Robert S. Salter, Steven J. Saul, and David W. Douglas
- Subjects
Chlortetracycline ,Canada ,medicine.drug_class ,Tetracycline ,Tetracycline antibiotics ,Sulfadimethoxine ,Food Contamination ,Oxytetracycline ,beta-Lactams ,Analytical Chemistry ,Cloxacillin ,medicine ,Environmental Chemistry ,Bulk tank ,Animals ,Food science ,Pharmacology ,Sulfonamides ,Microbiological Methods ,Chemistry ,Drug Residues ,Anti-Bacterial Agents ,Milk ,Tetracyclines ,Cattle ,Female ,Agronomy and Crop Science ,Ceftiofur ,Food Science ,medicine.drug - Abstract
A qualitative 3 min one-step assay for detecting beta-lactam, sulfonamide, and tetracycline antibiotics was validated following milk screening test guidelines developed by FDA-CVM, AOAC-RI, and IDF. The validated 90% detection levels with 95% confidence were: penicillin G 2 part per billion (ppb); amoxicillin 4 ppb; ampicillin 9 ppb; ceftiofur plus metabolites 50 ppb; cloxacillin 9 ppb; cephapirin 15 ppb; sulfadimethoxine 8 ppb; sulfamethazine 9 ppb; chlortetracycline 34 ppb; oxytetracycline 53 ppb; and tetracycline 42 ppb. Detection levels were lower than U.S. and Canadian allowable limits for milk and were consistent with most European Maximum Residue Limits. Tests of raw commingled cows’ milk indicated a low positive error rate of
- Published
- 2020
29. Soleris®Enterobacteriaceae for the Detection of Enterobacteriaceae in Select Foods: AOAC Performance Tested MethodSM 121901
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Robert Donofrio, Carolyn Montei, Preetha Biswas, Suzanne Jordan, Mark Mozola, Brooke Roman, Susan Alles, Gail Betts, and Linda Everis
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Pasteurization ,Laboratory testing ,Analytical Chemistry ,law.invention ,Dogs ,Enterobacteriaceae ,law ,Environmental Chemistry ,Animals ,Food science ,Mathematics ,Pharmacology ,Microbiological Methods ,biology ,Bacteria ,biology.organism_classification ,Yogurt ,Food ,Direct plating ,Ice cream ,Food Microbiology ,Agronomy and Crop Science ,Mozzarella cheese ,Food Science ,Automated method - Abstract
Background Soleris®Enterobacteriaceae is a growth-based, automated method for detection of Enterobacteriaceae in food. Objective A study was conducted to validate the Soleris method for detection of Enterobacteriaceae in select foods (pasteurized milk, yogurt, mozzarella cheese, ice cream, dried milk, pasteurized liquid egg, frozen cooked chicken, deli ham, lettuce, and dry dog food) at a threshold of ≥ 10 CFU/g of product. Methods Inclusivity and exclusivity of the Soleris method were assessed by testing 55 and 38 target and non-target bacterial strains, respectively. Matrix testing was performed with one naturally contaminated and nine inoculated foods. Efficacy of the Soleris method was compared to that of the ISO 21528-2:2017 direct plating reference method using probability of detection analysis. Independent laboratory testing was conducted to verify method performance in two matrixes (yogurt and deli ham). Method robustness, stability, and lot-to-lot consistency of the Soleris reagents were also assessed. Results Inclusivity of the Soleris test was 91% and exclusivity was 100%. In matrix testing, there were no significant differences in the number of positive results obtained with the Soleris and reference methods for any of the matrixes examined. Overall, of 370 test portions, there were 176 positive results by the Soleris method and 177 positive results by the reference procedure. Conclusions Soleris Enterobacteriaceae is an effective method for detection of Enterobacteriaceae in the foods evaluated, with performance equivalent to that of the ISO 21528-2:2017 reference method. Highlights The Soleris method offers the advantages of labor savings and results within 18 h.
- Published
- 2020
30. Aislamiento e identificación de microorganismos en biopelículas provenientes del Castillo de Chapultepec, Ciudad de México.
- Author
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E de la Cruz, J. Narváez Zapata, and Leandro Páramo Aguilera
- Subjects
Microbiology ,pure cultures ,biofilms ,isolation of microorganism ,microbiological methods ,biodeterioration processes. ,Technology ,Technology (General) ,T1-995 - Abstract
Today microbiology is based on pure cultures and separate microorganisms, pure cultures really do not exist in nature, because that microorganism are combined into large colonies slimy (biofilms) in which the various individuals establish relationships and dependencies. Only in the United State of America is estimated that biofilms cause billions of dollars in energy losses, equipment damage, product contamination and medical infections. This paper presents the results of the isolation of microorganisms by microbiological and molecular methods, from biofilms located in the Castle of Chapultepec in Mexico City. In the biofilm coexist different genres of filamentous fungi such as Cladosporium, Mucor, Alternaria, Aspergillus, Aureobasidium, Rhodotorula and others in those biofilms; besides bacterial genera as Bacillus, Pantoea, Kokuria, etc. Many of these microbial genera have been widely reported as a participating in biodeterioration processes to monuments and others are reported as contributing to its restoration, so this work opens the door to future researches that allow biological restoration of monuments, conservation and development of new biotechnological processes. Keywords: Microbiology; pure cultures; biofilms; isolation of microorganism; microbiological methods; biodeterioration processes.
- Published
- 2011
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31. Applicability of the EN ISO 11290-1 standard method for Listeria monocytogenes detection in presence of new Listeria species.
- Author
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Barre, Léna, Angelidis, Apostolos S., Boussaid, Djouher, Brasseur, Emilie Decourseulles, Manso, Eléonore, and Gnanou Besse, Nathalie
- Subjects
- *
FOOD microbiology , *LISTERIA monocytogenes , *PHENOTYPES , *BACTERIAL growth , *CO-cultures - Abstract
During the past six years, new species of the genus Listeria have been isolated from foods and other environmental niches worldwide. The Standard method EN ISO 11290-1 that is currently under revision will include in its scope all Listeria species in addition to L. monocytogenes . The objective of this project was to evaluate the ability of the Standard EN ISO 11290-1 method to detect and identify the newly discovered Listeria spp., and to assess potential over-growth effects of the new species in mixed cultures with L. monocytogenes during each step of the enrichment process. This objective was addressed by the generation of necessary data on the behavior of the new species during the pre-enrichment and the enrichment steps of the reference method as well as data on their phenotypic characteristics on rich and selective media used for isolation and identification. Most of the new Listeria species developed well on selective agar media for Listeria , however the recovery of some species was difficult due to poor growth in Half Fraser and Fraser broth. Good results (consistently positive) were obtained for confirmation at the genus level via the catalase test, the Gram test and the blueish appearance test on non-selective medium, but not with the VP test, as most of the new species yielded a negative result. In the light of results obtained in co-culture experiments and inhibition tests, and considering the growth rates in Half Fraser and Fraser broths, the new species do not seem to interfere with the detection of L. monocytogenes . [ABSTRACT FROM AUTHOR]
- Published
- 2016
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32. The challenge of enumerating Listeria monocytogenes in food.
- Author
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Auvolat, Anais and Besse, Nathalie Gnanou
- Subjects
- *
LISTERIA monocytogenes , *FOOD microbiology , *FOOD pathogens , *FOOD testing , *BACTERIAL cells , *POLYMERASE chain reaction - Abstract
Listeria monocytogenes is recognised as a serious foodborne pathogen in humans. However, food products are usually contaminated at low levels (i.e. <100 CFU/g) and there is still no adequate enumeration method for testing food. Much research has been carried out to improve Listeria enumeration methods, leading to several proposed alternative methods such as the most probable number technique, molecular-based methods and bacterial cell concentration techniques. Here, we catalogue the current knowledge concerning L. monocytogenes enumeration, with a particular focus on the problem of enumerating low level contamination. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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33. Clostridium botulinum spores in European honey bees from Serbia
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Dušan Mišić, G. Jevtic, Kazimir Matović, Jelena Ciric, Marko Dmitrić, Nebojša Nedić, and Neđeljko Karabasil
- Subjects
0106 biological sciences ,fungi ,food and beverages ,microbiological methods ,04 agricultural and veterinary sciences ,Biology ,medicine.disease_cause ,040401 food science ,01 natural sciences ,Microbiology ,Spore ,law.invention ,010602 entomology ,Honey Bees ,PCR ,0404 agricultural biotechnology ,law ,Insect Science ,Clostridium botulinum ,behavior and behavior mechanisms ,medicine ,Multiplex ,Apis mellifera ,Polymerase chain reaction - Abstract
A total of 61 honey bees from different regions of the Republic of Serbia were analyzed for Clostridium botulinum (C. botulinum) spores. The microbiological methods and molecular methods (multiplex PCR/mPCR and PCR method) were utilized to examine multiple subunits of each honey bees samples. The C. botulinum spores in PCR-positive samples were estimated by the most probable number method (MPN). The presence of C. botulinum spores, by applying mPCR and PCR methods, was detected in 1 of the 61 honey bees (1.64%). Using MPN method, the number of spores in positive sample was 110/kg. Detection of C. botulinum spores directly from untreated honey bees, without prior enrichment, is impossible by applying PCR. Using conventional microbiological methods, detection of C. botulinum spores in dead honey bees is not possible without preenrichment. Therefore, conventional, microbiological methods are not suitable for the detection of C. botulinum spores in honey bees. In order to detect C. botulinum spores in honey bees using PCR methods, due to the small and/or unequal distribution of spores in the samples, it is desirable to use multiple subunits/replicates for each sample examined.
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- 2019
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34. Izraba odpadne kisle sirotke za gojenje laktobacilov s probiotičnim potencialom
- Author
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Žohar, Tjaša and Bogovič Matijašić, Bojana
- Subjects
lactobacilli ,probiotic bacteria ,whey utilization ,kisla sirotka ,mikrobiološke metode ,bioprocess ,microbiological methods ,uporaba sirotke ,bioproces ,yeast extract ,bioreaktor ,bioreactor ,udc:637.344:602.4:579.864 ,kvasni ekstrakt ,laktobacili ,probiotične bakterije ,by-product ,stranski produkt ,acid whey - Abstract
Kisla sirotka je tekoč stranski produkt, ki nastane pri fermentaciji ali kisli koagulaciji mleka z dodatkom organske ali anorganske kisline. V primerjavi z obdelavo sladke sirotke je predelava kisle sirotke veliko zahtevnejša, predvsem zaradi večje vsebnosti mlečne kisline, ki otežuje proces sušenja. Kisla sirotka je zato pogosteje obravnavana kot odpadek in predstavlja ekološko obremenitev oziroma strošek za proizvajalca. Namen magistrskega dela je bil raziskati uporabnost kisle sirotke, ki nastane pri industrijski izdelavi skute, za gojenje bakterij s probiotičnim potencialom. V manjšem merilu smo najprej pokazali, da so bili vsi izbrani sevi sposobni rasti v gojišču iz kisle sirotke. Obogatitev kisle sirotke s kvasnim ekstraktom in/ali mešanico mineralov je izboljšala rast sevov Lactiplantibacillus plantarum in seva Lacticaseibacillus rhamnosus IM239, ni pa vplivala na rast seva Lactobacillus paragasseri IM105. V večjem merilu smo nato z gojenjem v bioreaktorju pokazali, da je bil izplen živih bakterij boljši, če tekom fermentacije vrednosti pH nismo uravnavali. Ugotovili smo tudi, da so testirane bakterije, odvzete na začetku stacionarne faze rasti, bolje preživele liofiliziranje, če smo jim tekom gojenja uravnavali vrednost pH na 6,5, medtem ko pri kulturah, odvzetih po 24-ih urah, vpliv vrednosti pH ni bil tako izrazit. Z raziskavo smo tako potrdili potencial kisle sirotke za industrijsko gojenje mlečnokislinskih bakterij. Acid whey is a liquid fraction that remains after the fermentation of milk or the addition of organic or mineral acids to milk. The processing of acid whey is much more challenging than the processing of sweet whey, mainly because of the higher lactic acid content, which obstructs the drying process. Acid whey is, therefore, more often considered as waste, and as such as an ecological burden for the environment and an unwanted cost for the manufacturer. The purpose of this study was to investigate the possibility of using acid whey as a culture medium for probiotic bacteria. The acid whey used was the by-product of an industrial-sized production of cottage cheese. We first showed on a smaller scale that the chosen bacterial strains were able to grow in an acid whey medium. The addition of yeast extract and/or a mixture of minerals improved the growth of the Lactiplantibacillus plantarum strains and the Lacticaseibacillus rhamnosus IM239 strain, but it did not affect the growth of the Lactobacillus paragasseri IM105 strain. Then we showed on a larger scale that the yield of live bacteria was higher if the pH value was not regulated during the fermentation in a bioreactor. We also showed that the bacteria samples collected at the beginning of the stationary growth phase had a higher survival rate during freeze-drying if their pH value was adjusted to 6,5 during the fermentation. However, in the samples collected after 24 hours the pH value had a smaller effect on the survival rate during freeze-drying. With the study we thus confirmed that acid whey can be used as a growth medium for the cultivation of lactic acid bacteria.
- Published
- 2021
35. Performance Evaluation of an Italian Reference Method, the ISO Reference Method and a Chromogenic Rapid Method for the Detection of E. coli and Coliforms in Bottled Water.
- Author
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Pasquale, Simona and Medici, Dario
- Abstract
Bottled water can be contaminated by coliforms and/or Escherichia coli ( E. coli). These bacteria are considered as indicators of faecal pollution, and their detection in bottled water indicates the potential contamination by pathogenic enteric microorganisms. In recent decades, different methods were developed for the detection of coliforms and E. coli in drinking water and in bottled water including mineral water. Since 1976, the Italian regulation has defined microbiological methods to evaluate microbiological characteristics of mineral waters. Three different methods for the detection of coliforms and E. coli in bottled water were compared in this study: the Italian reference method, according to the 'Italian Ministerial Rule,' the ISO 9308-1:2002 method, and a new rapid method. The results have demonstrated that the ISO method 9308-1:2002 and the new rapid method are as sensitive and specific as Italian reference method, and that both could be used to evaluate the contamination level of coliform and E. coli in drinking water and in bottled water including mineral water. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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36. The Investigation of the Presence of Clostridium Botulinum Spores in Honey in Serbia.
- Author
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Matovic, Kazimir, Baltic, Milan, Nedic, Nebojsa, Dmitric, Marko, Nenadic, Dragan, Vaskovic, Nikola, Jevtic, Goran, and Misic, Dusan
- Abstract
The presence of Clostridium botulinum spores in 59 honey samples originating from different regions of the Republic of Serbia was studied. In addition to microbiological methods, after enrichment, centrifugation and membrane filtration, molecular methods (PCR methods) were utilized. The number of spores in PCR positive samples was estimated by the most probable number (MPN) method. PCR confirmed C. botulinum spores in 5 (8.47%) honey samples. MPN of spores varied from 20/kg to 204/kg honey. PCR was more sensitive than cultural methods. Natural honey contamination with C. botulinum spores is low-level and not homogeneous, and therefore, PCR methods require multiple sub-sampling. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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37. Sensitive enumeration of Listeria monocytogenes and other Listeria species in various naturally contaminated matrices using a membrane filtration method.
- Author
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Barre, Léna, Brasseur, Emilie, Doux, Camille, Lombard, Bertrand, and Besse, Nathalie Gnanou
- Subjects
- *
LISTERIA monocytogenes , *FOOD pathogens , *MEMBRANE separation , *EVALUATION research , *FOOD research - Abstract
For the enumeration of Listeria monocytogenes ( L. monocytogenes ) in food, a sensitive enumeration method has been recently developed. This method is based on a membrane filtration of the food suspension followed by transfer of the filter on a selective medium to enumerate L. monocytogenes . An evaluation of this method was performed with several categories of foods naturally contaminated with L. monocytogenes . The results obtained with this technique were compared with those obtained from the modified reference EN ISO 11290-2 method for the enumeration of L. monocytogenes in food, and are found to provide more precise results. In most cases, the filtration method enabled to examine a greater quantity of food thus greatly improving the sensitivity of the enumeration. However, it was hardly applicable to some food categories because of filtration problems and background microbiota interference. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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38. PhageDx™ E. coli O157:H7 Assay in Ground Beef Level 3 Modification to Add 375 g Beef Trim and New Method Procedure for 25 g Ground Beef: AOAC Performance Tested MethodSM 081601
- Author
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José J. Gil, Minh Mindy Bao Nguyen, and Stephen Erickson
- Subjects
AcademicSubjects/SCI01140 ,AcademicSubjects/SCI01060 ,AcademicSubjects/SCI00030 ,Colony Count, Microbial ,Food Contamination ,Escherichia coli O157 ,AcademicSubjects/SCI01180 ,01 natural sciences ,Rapid detection ,Trim ,Analytical Chemistry ,Lysis buffer ,Environmental Chemistry ,Animals ,Test sample ,Pharmacology ,Chromatography ,Microbiological Methods ,010405 organic chemistry ,Chemistry ,010401 analytical chemistry ,0104 chemical sciences ,Culture Media ,Meat Products ,Food Microbiology ,Cattle ,AcademicSubjects/SCI00980 ,Agronomy and Crop Science ,Food Science - Abstract
Background ThePhageDx™ E. coli O157:H7 Assay originally required a 5 h enrichment period and a 10 mL test sample for 25 g ground beef. The proposed method modifications seek to include beef trim (375 g) matrix and a new method procedure for 25 g ground beef comprised of 6–7 h enrichment and 1 mL test sample. Objective To validate the method modifications for PhageDx E. coli O157:H7 Assay to include beef trim (375 g) matrix and modify enrichment time and test sample size for 25 g ground beef. Method For both matrixes, pre-warmed tryptic soya broth (TSB; 42 ± 1°C) was added in a 3:1 (media:sample size) ratio, blended, and enriched for 9–10 h (beef trim, 375 g) or 6 h (ground beef, 25 g) at 42 ± 1°C. One milliliter samples were transferred to a microfuge tube, centrifuged, and the supernatant removed. The pellet was resuspended in 0.2 mL of TSB and phage reagent was added. Samples were incubated for 2 h at 37 ± 1°C. After infection, the sample was centrifuged, and 150 µl of the supernatant was transferred to a 96-well plate. Then, lysis buffer and luciferase substrate were added and the sample read on a luminometer to determine the presence or absence of E. coli O157:H7. Results No significant differences were found between the PhageDx E. coli O157:H7 Assay method modifications and the U.S. Department of Agriculture Food Safety and Inspection Service (FSIS) Microbiology Laboratory Guidebook (MLG) reference method. Conclusions The independent study demonstrated that the PhageDx E. coli O157:H7 Assay method modifications meet the qualifications for Performance Tested Method SM status. Highlights The PhageDx E. coli O157:H7 Assay is a rapid detection method capable of detecting E. coli O157:H7 in 25 g ground beef and 375 g beef trim samples in as little as 8.5 h and 11.5 h total turn around time, respectively.
- Published
- 2021
39. Mikrobiologische und biologische Methoden des Europäischen Arzneibuchs.
- Author
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Norwig, J.
- Abstract
Copyright of Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
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40. Določanje bakterij vrst Salmonella enterica in Listeria monocytogenes s PCR v realnem času
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Ledinek, Sebastjan and Jeršek, Barbara
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specifičnost PCR v realnem času ,udc:579.67.083:577.2.083 ,specificity of real-time PCR ,Salmonella enterica ,mikrobiološke metode ,microbiological methods ,pathogenic bacteria ,sensitivity of real-time PCR ,Listeria monocytogenes ,patogene bakterije ,občutljivost PCR v realnem času ,PCR v realnem času ,določanje bakterij ,real-time PCR - Published
- 2020
41. Optimizacija metod odkrivanja in shranjevanja termotolerantnih bakterij rodu Campylobacter v rutinskem laboratoriju
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Vek, Mojca and Smole Možina, Sonja
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limit of detection ,temperatura zamrzovanja ,polymerase chain reaction ,dolgotrajno shranjevanje ,microbiology ,detection ,Campylobacter ,mikrobiološke metode ,microbiological methods ,patogeni mikroorganizmi ,long-term preservation ,potrditev prisotnosti ,PCR ,verižna reakcija s polimerazo ,meja detekcije ,patogens ,udc:579.24+579.26+579.8 - Published
- 2020
42. Preverjanje trajnosti izbranih bakterioloških gojišč
- Author
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Plazar, Simona and Seme, Katja
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culture media ,MIO culture medium ,življenjska doba gojišč ,agar King B ,agar DNAA ,mikrobiološke metode ,microbiological methods ,agar CLED ,gojišče GOI ,kakovost gojišč ,gojišča ,agar MAC ,agar Campy ,agar XLD ,quality of culture media ,shelf-life of culture media ,agar MHR ,udc:579.083 ,agar ORSAB ,agar SS - Published
- 2020
43. Biological detoxification and removal mechanisms of ochratoxin A
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Vukšić, Lucija and Markov, Ksenija
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fizikalne metode ,detoksifikacija ,BIOTEHNIČKE ZNANOSTI. Biotehnologija ,physical methods ,kemijske metode ,mikrobiološke metode ,microbiological methods ,chemical methods ,Okratoksin A ,detoxification ,Ochratoxin A (OTA) ,BIOTECHNICAL SCIENCES. Biotechnology - Abstract
Okratoksin A (OTA) se smatra jednim od najopasnijih mikotoksina koji se nalaze u prehrambenim proizvodima, a kao glavni izvori OTA u ljudskoj prehrani navode se žitarice i vino. Istraživanja su pokazala da ima nefrotoksično, karcinogeno, imunotoksično, mutageno i neurotoksično djelovanje te je klasificiran kao mogući ljudski karcinogen. Osim preventivnih postupaka koji se primjenjuju kako bi se smanjio rizik od kontaminacije, potrebno je stalno kontrolirati razinu mikotoskina u hrani. Metode koje se koriste za smanjenje OTA dijele se na fizikalne, kemijske i mikrobiološke metode. Zbog ograničene primjene fizikalnih i kemijskih metoda, koriste se mikrobiološke metode koje su ekološki prihvatljive i učinkovite. Ochratoxin A (OTA) is considered as one of the most dangerous mycotoxins found in food products, and cereal and wine are reported as a main source of OTA in the human diet. Previous studies have shown that it has nephrotoxic, carcinogenic, immunotoxic, mutagenic and neurotoxic effects and it has been classified as a possible human carcinogenic. Besides preventive procedures that are applied to reduce the risk of contamination, what is necessary is a constant control of the levels of mycotoxins in food. The methods used to reduce OTA are physical, chemical or microbiological. Due to the limited application of physical and chemical methods, more environmentally friendly and efficient methods are more used.
- Published
- 2020
44. AOAC-OMA/MicroVal Harmonized Validation of Peel PlateTM EB (Enterobacteriaceae Bacteria), First Action 2018.05
- Author
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Benjamin Bastin, Gregory W. Durbin, Erin Crowley, Denisse Martinez, Robert S. Salter, and Patrick Bird
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Colony Count, Microbial ,Levonorgestrel ,Analytical Chemistry ,law.invention ,Probiotic ,Enterobacteriaceae ,law ,Environmental Chemistry ,Food microbiology ,Animals ,Humans ,Food science ,Incubation ,Gram ,Pharmacology ,Microbiological Methods ,biology ,Chemistry ,Infant ,biology.organism_classification ,Cronobacter sakazakii ,Culture Media ,Milk ,Infant formula ,Food Microbiology ,Edible Grain ,Agronomy and Crop Science ,Bacteria ,Food Science - Abstract
Background Peel PlateTM Enterobacteriaceae Bacteria (EB) is dried selective media on a 47 mm plastic plate that produces enzyme substrate colored colonies on rehydration and incubation for 24 h and up to 48 h at 37 ± 1°C. Purpose The method validation compared quantification of EB to reference methods ISO 21528:2017 Parts 1 and 2. Methods Matrixes compared were whole milk, skim powdered milk, vanilla ice cream, butter, infant formulas (soy- and dairy-based), infant cereals ± probiotic, environmental sponge swab of stainless steel surface, and poultry carcass rinse with two different peptone buffers. Results In inclusivity and exclusivity studies, the method detected 54 of 54 EB strains and did not detect 30 of 30 non-EB strains. In matrix studies, the claimed foods were tested at three contamination levels using paired analysis between the reference and Peel Plate EB methods. Colony-forming units per gram or mL [CFU/g (mL)] were log10 transformed for statistical analysis. The candidate method and reference method were shown to be equivalent by the performance requirement of all 95% confidence intervals on mean difference falling between −0.5 and +0.5 log10 CFU/g (mL). An international collaborative study with dried infant formula spiked with Cronobacter sakazakii at log10 CFU/g (mL) 1.05, 2.31, and 3.21 levels, produced method differences −0.16, 0.15, and 0.18 log10 CFU/g (mL) with repeatabilities (r) = 0.33, 0.20, and 0.12 log10 CFU/g (mL) and reproducibilities (R) = 0.45, 0.26, and 0.18 log10 CFU/g (mL). Conclusions Based on these evaluations, the candidate method is considered equivalent to the reference methods at both the 24 h and 48 h incubation periods at 37 ± 1°C. Highlights Ready to use Enterobacteriaceae method equivalent to ISO-21528:2017 Parts 1 and 2; EB test colored colonies at 37°C for 24 h are equivalent at 48 h incubation; Singlet determined CFU/mL are statistically the same as duplicate average results; EB test validated for infant formula and dairy products including with probiotics; EB test for environmental surfaces and poultry carcass rinses using peptone buffers.
- Published
- 2020
45. Comparison of the ISO method and three modifications of it for the enumeration of low concentrations of Listeria monocytogenes in naturally contaminated foods
- Author
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Barre, Lena, Skjerdal, Taran, Brasseur, Emilie, Papa-Georgiou, Georgios T., Odiatou, Elena M., Bulawova, Hana, Auvolat, Anais, Favret, Sarah, Lombard, Bertrand, and Gnanou Besse, Nathalie
- Subjects
Enumeration ,Food ,Listeria monocytogenes ,Microbiological methods ,Filtration - Abstract
Sensitive methods for enumeration of Listeria monocytogenes (L. monocytogenes) are needed to verify compliance with microbiological criteria in ready-to-eat foods. Here, we assessed the reference EN ISO 11290-2 method and three modifications of it with lower threshold levels for enumeration in terms of specificity, false results and practical limitations for use. Two of the methods, called the EURL and the Cyprus protocols, use membrane filtration to obtain a more concentrated test suspension, and the third, called the Norway protocol, uses less diluent. This study included 18 samples of foods naturally contaminated with L. monocytogenes at concentrations of 0.2-80 CFU/g. All four tested methods yielded valid results with good repeatability (Fisher’s test, p, FR; PDF; corresponding author: lena.barre@anses.fr, {"references":["AFNOR. 1998. Analyse des produits agricoles et alimentaires – Procédure de validation intra-laboratoire d'une méthode alternative par rapport à une méthode de référence – Cas de méthodes d'analyse quantitatives. AFNOR NF V03-110; Association française de normalisation, La Plaine Saint-Denis, France","AFNOR. 2009. Poissons transformés - Méthode pour le dénombrement de Listeria monocytogenes aux faibles niveaux de contamination dans le saumon fumé et la truite fumée.","NF V45-008. Association française de normalisation, La Plaine Saint-Denis, France","Anonymous. 2000. Rapport de la commission d'étude des risques liés à Listeria monocytogenes, juillet 2000, AFSSA. Maisons Alfort : Agence française de sécurité sanitaire des aliments, 143 p.","Barre L, Brasseur E, Doux C, Lombard B, Gnanou Besse N. 2015. Sensitive enumeration of Listeria monocytogenes and other Listeria species in various naturally contaminated matrices using a membrane filtration method. Food microbiology 48:171-177.","Baudouin N, Lombard B, Audinet N, Gnanou Besse N. 2010. Enumeration of Listeria monocytogenes at low contamination levels in several food matrices using a membrane filtration method. Food Analytical Methods 3:54-64.","Buchanan RL, Gorris LGM, Hayman MM, Jackson TC, Whiting RC. 2017. A review of Listeria monocytogenes: An update on outbreaks, virulence, dose-response, ecology, and risk assessments. Food Control, 75:1-13, 10.1016/j.foodcont.2016.12.016","EFSA. 2007. Scientific opinion of the panel on biological hazards on a request from the European Commission on Request for updating the former SCVPH opinion on Listeria monocytogenes risk related to ready-to-eat foods and scientific advice on different levels of Listeria monocytogenes in ready-to-eat foods and the related risk for human illness. EFSA Journal 59:1-42.","European Food Safety Authority (EFSA) and European Centre for Disease Prevention and Control (ECDC). 2012. The European Union Summary Report on Trends and Sources of Zoonoses, Zoonotic Agents and Food-borne Outbreaks in 2010. EFSA Journal 10(3):2597.","EFSA BIOHAZ Panel (EFSA Panel on Biological Hazards), Ricci A, Allende A, Bolton D, Chemaly M, Davies R, Fernández Escámez PS, Girones R, Herman L, Koutsoumanis K, Nørrung B, Robertson L, Ru G, Sanaa M, Simmons M, Skandamis P, Snary E, Speybroeck N, Ter Kuile B, Threlfall J, Wahlström H, Takkinen J, Wagner M, Arcella D, Da Silva Felicio MT, Georgiadis M, Messens W, Lindqvist R. 2018. Scientific Opinion on the Listeria monocytogenes contamination of ready-to-eat foods and the risk for human health in the EU. EFSA Journal 16(1):5134, 173 pp.","Gnanou Besse N, Beaufort A, Rudelle S, Denis C, Lombard B. 2008. Evaluation of an enumeration method for Listeria monocytogenes at low contamination levels in cold-smoked salmon. International Journal of Food Microbiology 124: 271-274.","Gnanou Besse N, Audinet N, Barre L, Cauquil A, Cornu M, Colin P. 2006. Effect of the inoculum size on Listeria monocytogenes growth in solid media. International Journal of Food Microbiology 110:43-51.","Gnanou Besse N, Colin P. 2004. Enumerating Listeria monocytogenes in food: a problem of low numbers. Journal of Rapid Methods and Automation in Microbiology 12: 83-105.","Hunt K, Vacelet M, Jordan K. 2017. Determination of Listeria monocytogenes numbers at less than 10 CFU/g. Irish Journal of Agricultural and Food Research 56(1):25-30","ISO. 1998. Microbiology of food and animal feeding stuffs - horizontal method for detection and enumeration of Listeria monocytogenes, part 2. Enumeration method. International standard ISO 11290-2. Geneva: International Organisation for Standardisation.","ISO. 2004. Microbiology of food and animal feeding stuffs - Horizontal method for detection and enumeration of Listeria monocytogenes, Part 2. Enumeration method, Amendment 1: 2004. Modification of the enumeration medium. International Standard ISO 11290-2. Geneva: International Organisation for Standardisation.","Jadhav S, Bhave M, Palombo EA. 2012. Methods used for the detection and subtyping of Listeria monocytogenes. Journal of microbiological methods 88(3):327-341.","Skjerdal T, Reitehaug E, Eckner K. 2014. Development of performance objectives for Listeria monocytogenes contaminated salmon (Salmo salar) intended used as sushi and sashimi based on analysis of naturally contaminated samples. International Journal of Food Microbiology 184:8-13","Välimaa AL, Tilsala-Timisjärvi A, Virtanen E. 2015. Rapid detection and identification methods for Listeria monocytogenes in the food chain–A review. Food Control 55:103-114."]}
- Published
- 2020
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- View/download PDF
46. The human urinary microbiome; bacterial DNA in voided urine of asymptomatic adults.
- Author
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Lewis, Debbie A., Brown, Richard, Williams, Jon, White, Paul, Jacobson, Kim, Marchesi, Julian R., and Drake, Marcus J.
- Subjects
BACTERIAL DNA ,ESCHERICHIA coli DNA ,RIBOSOMAL RNA ,RNA ,URINE - Abstract
The urinary microbiome of healthy individuals and the way it alters with ageing have not been characterized and may influence disease processes. Conventional microbiological methods have limited scope to capture the full spectrum of urinary bacterial species. We studied the urinary microbiota from a population of healthy individuals, ranging from 26 to 90 years of age, by amplification of the 16S rRNA gene, with resulting amplicons analyzed by 454 pyrosequencing. Mid-stream urine (MSU) was collected by the "clean-catch" method. Quantitative PCR of 16S rRNA genes in urine samples, allowed relative enumeration of the bacterial loads. Analysis of the samples indicates that females had a more heterogeneous mix of bacterial genera compared to the male samples and generally had representative members of the phyla Actinobacteria and Bacteroidetes. Analysis of the data leads us to conclude that a "core" urinary microbiome could potentially exist, when samples are grouped by age with fluctuation in abundance between age groups. The study also revealed age-specific genera Jonquetella, Parvimonas, Proteiniphilum, and Saccharofermentans. In conclusion, conventional microbiological methods are inadequate to fully identify around two-thirds of the bacteria identified in this study. Whilst this proof-of-principle study has limitations due to the sample size, the discoveries evident in this sample data are strongly suggestive that a larger study on the urinary microbiome should be encouraged and that the identification of specific genera at particular ages may be relevant to pathogenesis of clinical conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
47. Potential applications of rapid microbiological methods for detection of antibiotic residues in wastewater, surface and well water.
- Author
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GODIČ TORKAR, Karmen and FINK, R.
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SEWAGE purification , *MICROBIOLOGY , *ANTIBIOTIC residues , *WELL water , *WATER testing , *WATER sampling - Abstract
The goal of the present study was to determine whether the commercial microbiological and tracer assays for the detection of antibiotics in the food were also useful and sensitive enough for testing water samples. Diffusion tests Delvotest® SP-NT and BRT-AiM showed the similar sensitivity to tested antibiotics in spiked water samples. Both tests showed the similar sensitivity to examined antibiotics in water as it was published in milk, while tracer assay BetaStar showed slightly higher minimum detection levels for penicillin and ampicillin but not for cloxacillin. The previous concentration of the samples by lyophilization took place to detect concentrations of antibiotics 100-fold lower than there were the minimum detection limits of the assays. The presence of inhibitory substances in surface and well samples was detected in 16 (16.3 %) cases out of 98 with both ampoule diffusion methods. The positive results were obtained at 15.0 % of surface water samples, while in well water the residues were found also in 16.9 % and 13.6 % samples, using Delvotest SP-NT and BRT-AiM, respectively. The β-lactams were detected with BetaStar in 7.5 % of surface water samples. The 12 wastewater samples from hospitals were contaminated with inhibitory substances in 45.5 % (Delvotest SP-NT) or in 36.4 % (BRT-AiM). [ABSTRACT FROM AUTHOR]
- Published
- 2013
48. Screening of Antibiotics Residues in Poultry Meat by Microbiological Methods.
- Author
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HAKEM (ex AKAM), A., TITOUCHE, Y., HOUALI, K., YABRIR, B., MALKI, O., CHENOUF, N., YAHIAOUI, S., LABIAD, M., GHENIM, H., KECHIH-BOUNAR, S., CHIRILĂ, F., LAPUSAN, A., and FIŢ, N.I.
- Subjects
ANTIBIOTICS ,MEAT industry ,PROTEINS ,POULTRY farming ,ANIMAL products ,FOOD contamination - Abstract
Antibiotics are efficiency substances for the treatment and improvement of animal production yields. However, their irrational and non-moderate using can cause serious problems for the consumer and the manufacturer. The aim of this study is to check their presence in the poultry meat by conventional microbiological methods (four boxes) recommended and approved by French Agency of Food Safety (AFSSA). For this purpose, 145 poultry meat samples were taken from various breeding farms and tested by Plates Agar diffusion at different pH (6, 7.2 and 8), seeded by two references strains: Bacillus subtilis (BGA spores) and Micrococcus luteus (ATCC 9341). The results revealed that 124 out of 145 poultry meat samples were positive to antibiotic residues with the percentage of 85.51%. However, most of them contained 75.81% of β-lactams and/or Tetracyclines against 44.35% for Macrolides and/or β-Lactams and 36.29% for Sulfonamides. Conversely, 13.71% of samples were positive to aminoglycosides. The study confirms the misuses and non compliance of the withdrawal period between the administration of antibiotic in animal and its slaughter. Therefore, control of antibiotic residues should be a future concern for both producers and processor in order to protect health's consumers. [ABSTRACT FROM AUTHOR]
- Published
- 2013
49. MICROBIOLOGICAL ANALYSIS OF FAST FOOD MEAT PRODUCTS IN TUZLA AREA.
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Perić, Milan, Lonić, Elvira, Hodžić, Snježana, Šabanović, Marizela, and Hajdarević, Edina
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FOOD microbiology , *FOOD chemistry , *MEAT , *FOOD of animal origin , *PATHOGENIC microorganisms - Abstract
Food used to be and is still one of the key factors of human adaptation to surroundings. Human need for food is tightly connected with soil fertility, climate and finally with sources of nourishment. However, besides man, other living creatures, like microorganisms, insects, as well as other animals, know about available sources of nourishment on Earth. Human beings are the only species from the animal world that tend to adapt the surroundings to their particular needs. Apart from milk, the most appreciated foodstuff in nutrition, meat is very significant as well, because it is a source of easily digestible and biologically and energetically valuable ingredients. Therefore, meat is one of the most frequent foodstuffs in human nutrition and it is necessary to control it especially in places where people often eat. The results of the microbiological analysis of meat samples taken in 10 different fast food restaurants are shown in this study. The selected samples were analyzed using the standard microbiological method, and the results of the analysis show that all samples were microbiologically sound since the total number of bacteria in 1g of the sample was within acceptable limits. In favor to this is the fact that the pathogenic microorganisms harmful to human health were not found. [ABSTRACT FROM AUTHOR]
- Published
- 2011
50. Enumeration of Listeria monocytogenes at Low Contamination Levels in Several Food Matrices Using a Membrane Filtration Method.
- Author
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Baudouin, Nicolas, Lombard, Bertrand, Audinet, Nelly, and Gnanou Besse, Nathalie
- Abstract
For the enumeration of Listeria monocytogenes in cold-smoked salmon, a sensitive enumeration method, based on membrane filtration followed by transfer of the filter on a selective medium, has been recently developed. An evaluation of this method was performed with several categories of foods likely to be contaminated with L. monocytogenes. The results obtained with the technique were compared with those from the reference EN ISO 11290-2 method and found to provide more precise results in the enumeration of L. monocytogenes from both artificially and naturally contaminated products. In most cases, the filtration method enabled a greater quantity of food to be examined (from around 0.5 to 14 g, instead of 0.01 to 0.1 g with the reference EN ISO 11290-2 method), thus greatly improving the sensitivity of the enumeration. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
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