A New Protocol to Detect Multiple Foodborne Pathogens with PCR Dipstick DNA Chromatography after a Six-Hour Enrichment Culture in a Broad-Range Food Pathogen Enrichment Broth

A quick foodborne pathogen screening method after six-hour enrichment culture with a broad-range food pathogen enrichment broth is described. Pathogenic factors ofSalmonella enterica,Shigellaspp., enteroinvasiveEscherichia coli, and enterohemorrhagicE. coliare amplified with a cocktail primer and rapid polymerase chain reaction (PCR), which finishes amplification in 30 min. The PCR amplicon was differentiated with a dipstick DNA chromatography assay in 5–10 min. Starting from a four- to six-hour enrichment culture, this assay was finished within 45 min. Detection sensitivity of this protocol was less than 2.5 CFU/25 g forS. entericaand 3.3 CFU/25 g for enterohemorrhagicE. coliin spiked ground meat experiments.

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An Aggregation-Induced Emission Material Labeling Antigen-Based Lateral Flow Immunoassay Strip for Rapid Detection of Escherichia coli O157:H7

SLAS TECHNOLOGY Translating Life Sciences Innovation ◽

10.1177/2472630320981935 ◽

2021 ◽

pp. 247263032098193

Author(s):

Cheng Liu ◽

Shuiqin Fang ◽

Yachen Tian ◽

Youxue Wu ◽

Meijiao Wu ◽

...

Keyword(s):

Escherichia Coli ◽

Rapid Detection ◽

Foodborne Pathogen ◽

Test Strip ◽

Lateral Flow ◽

Detection Sensitivity ◽

Lateral Flow Immunoassay ◽

Escherichia Coli O157 ◽

Aggregation Induced Emission ◽

E Coli

Escherichia coli O157:H7 ( E. coli O157:H7) is a dangerous foodborne pathogen, mainly found in beef, milk, fruits, and their products, causing harm to human health or even death. Therefore, the detection of E. coli O157:H7 in food is particularly important. In this paper, we report a lateral flow immunoassay strip (LFIS) based on aggregation-induced emission (AIE) material labeling antigen as a fluorescent probe for the rapid detection of E. coli O157:H7. The detection sensitivity of the strip is 105 CFU/mL, which is 10 times higher than that of the colloidal gold test strip. This method has good specificity and stability and can be used to detect about 250 CFU of E. coli O157:H7 successfully in 25 g or 25 mL of beef, jelly, and milk. AIE-LFIS might be valuable in monitoring food pathogens for rapid detection.

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An Improved Screening Method for the Detection and Isolation of Escherichia coli 0157:H7 From Meat, Incorporating the 3M Petrifilm™ Test Kit - HEC - for Hemorrhagic Escherichia coli 0157:H7

Journal of Food Protection ◽

10.4315/0362-028x-53.11.936 ◽

1990 ◽

Vol 53 (11) ◽

pp. 936-940 ◽

Cited By ~ 41

Author(s):

ANITA J. G. OKREND ◽

BONNIE E. ROSE ◽

RICHARD MATNER

Keyword(s):

Escherichia Coli ◽

Screening Program ◽

Enrichment Culture ◽

Screening Method ◽

Meat Sample ◽

E Coli ◽

Enrichment Cultures ◽

Poultry Products ◽

Test Kit ◽

Cooked Meat

A screening method was devised incorporating a commercially available reactive disc blot ELISA for Escherichia coli 0157 antigen, into a cultural screening program for the isolation of E. coli 0157:H7 from meat and poultry products. The method includes the inoculation of a raw or cooked meat sample into an enrichment broth, incubation with shaking at 37°C for 6 to 8 h, followed by inoculation of 3M Petrifilm™ E. coli Count plates with dilutions of the enrichment culture. The Petrifilm plates were incubated at 42°C for 18 h and tested for the presence of the 0157 antigen. The enrichment cultures were reincubated static at 35°C after the initial shaken incubation. Isolation was attempted from the positive Petrifilm plates by both a direct picking and streaking method and by the 3M Prompt™ isolation method. Isolation also was attempted from the 24-h enrichment cultures by spread plating serial dilutions on 150 × 15 mm MacConkey sorbitol agar (MSA) and MSA with 5-bromo-4-chloro-3-indoxyl-β-D-glucuronic acid cyclohexylammonium salt (BCIG). This fast and efficient screening procedure identifies negative and presumptive positive samples in 26–28 h. Isolation and confirmation of the presumptive positive isolates require an additional 3 to 4 d.

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Evaluation of Treatments for Elimination of Foodborne Pathogens on the Surface of Leaves and Roots of Lettuce (Lactuca sativa L.)

Journal of Food Protection ◽

10.4315/0362-028x-72.2.228 ◽

2009 ◽

Vol 72 (2) ◽

pp. 228-234 ◽

Cited By ~ 29

Author(s):

GUODONG ZHANG ◽

LI MA ◽

LARRY R. BEUCHAT ◽

MARILYN C. ERICKSON ◽

VANESSA H. PHELAN ◽

...

Keyword(s):

Lactuca Sativa ◽

Foodborne Pathogens ◽

Fluorescent Protein ◽

Enrichment Culture ◽

Factors Affecting ◽

Surface Disinfection ◽

E Coli ◽

Leaf Piece ◽

Lactuca Sativa L ◽

Leaves And Roots

Several outbreaks of Salmonella and Escherichia coli O157:H7 infections have been associated with consumption of leafy greens. Questions remain concerning the ability of these pathogens to become internalized within lettuce and spinach tissues. An effective validated surface disinfection method for lettuce is needed before factors affecting internalization of pathogens can be studied. The objective of this study was to develop a surface disinfection method for lettuce leaves and roots. Iceberg lettuce (Lactuca sativa L.) leaves cut into pieces (3 by 3 cm) and lettuce roots were inoculated by immersing in suspensions of five-strain mixtures of green fluorescent protein–labeled E. coli O157:H7, Salmonella, or Listeria monocytogenes at populations of 7 to 8 log CFU/ml for 10 min at 20 ± 1°C. Inoculated samples were placed in a laminar flow biosafety cabinet for 30 min before treating with disinfectants. Thirteen surface disinfection methods were compared for their efficacy in killing E. coli O157:H7 on lettuce leaf and root surfaces. E. coli O157:H7 initially at 5.8 or 6.8 log CFU/leaf piece or root was not detected by enumeration (<0.6 log CFU per leaf piece) on samples treated for 20 min with 10,000 μg/ml sodium hypochlorite (NaHClO) or in solutions containing ethanol and mercuric chloride (HgCl2). With all other methods, E. coli O157:H7 populations ranged from 2.8 to 4.4 CFU per leaf piece or root after treatment. Trends in leaf and root print and enrichment culture results were consistent with enumeration results. Dipping in 80% ethanol for 10 s followed by immersion in 0.1% HgCl2 for 10 min was determined to be the most effective surface disinfection method for inactivating E. coli O157:H7 on lettuce leaves and roots and was also validated for inactivating Salmonella and L. monocytogenes.

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Efficacy of Bacteriophage Cocktail to Control E. coli O157:H7 Contamination on Baby Spinach Leaves in the Presence or Absence of Organic Load

Microorganisms ◽

10.3390/microorganisms9030544 ◽

2021 ◽

Vol 9 (3) ◽

pp. 544

Author(s):

Badrinath Vengarai Jagannathan ◽

Steven Kitchens ◽

Paul Priyesh Vijayakumar ◽

Stuart Price ◽

Melissa Morgan

Keyword(s):

Foodborne Pathogens ◽

Fruits And Vegetables ◽

Healthy Lifestyle ◽

Foodborne Pathogen ◽

Organic Load ◽

Lytic Bacteriophage ◽

Foodborne Illnesses ◽

E Coli ◽

Pathogen Reduction ◽

Spinach Leaves

Fruits and vegetables are high in nutrients that are essential for a healthy lifestyle. However, they also harbor an extensive array of microorganisms such as bacteria, which can be beneficial, neutral, or pathogenic. Foodborne pathogens can contaminate produce at any stage from the farm to the consumer’s table. Appropriate washing techniques using sanitizers can reduce the risk of pathogen contamination. Issues related to maintaining concentration, efficacy, and other problems have been a challenge for the food industry and, when left unresolved, have led to different outbreaks of foodborne illnesses. In this study, the efficacy of a lytic bacteriophage cocktail was examined for its ability to infect and reduce the contamination of Escherichia coli O157:H7 (E. coli O157:H7), in media with a high organic load, using a microplate technique. The study was conducted for 3 h to determine if the bacteriophage cocktail could reduce the pathogen in the presence of a high organic load. A significant (p < 0.05) reduction in the population of E. coli O157:H7 was observed, representing a 99.99% pathogen reduction at the end of 3 h. Fresh spinach leaves were washed in sterile potable or organic water (~9000 ppm organic load) containing E. coli O157:H7 and a bacteriophage cocktail to study the effectiveness of bacteriophages against the foodborne pathogen. Results indicated that the bacteriophage significantly (p < 0.05) reduced the contamination of E. coli O157:H7 in both situations. The study also demonstrated the bacteriophages’ ability to infect and reduce the pathogen in an organic-rich environment. This characteristic differs from commercially available sanitizers that have demonstrated a tendency to bind with the available organic load. Thus, these studies highlight the advantage of employing bacteriophages during produce wash to eliminate foodborne pathogen contamination on fruits and vegetables.

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Antimicrobial Effect of Guava Products against Foodborne Pathogens

HortScience ◽

10.21273/hortsci.39.4.778a ◽

2004 ◽

Vol 39 (4) ◽

pp. 778A-778

Author(s):

Guochen Yang* ◽

Salam A. Ibrahim ◽

Carl E. Niedziela

Keyword(s):

Foodborne Pathogens ◽

Block Design ◽

Foodborne Pathogen ◽

Water Extract ◽

Antimicrobial Effect ◽

Viable Cell ◽

Leaf Extracts ◽

E Coli ◽

Cell Counts ◽

Survival And Growth

This study investigated antimicrobial effects of guava products on the survival and growth of Escherichia coli O157:H7 in liquid medium. Seven strains of E. coli O157:H7 (944, 380, E0019, F4546, H1730, Cider, 9727) were tested. These strains were maintained in BHI broth. Guava fruits were sliced into small pieces and blended using a blender. Guava juice and leaves were then extracted using three solvents: water, methanol and hexane. Fruit extracts were dissolved in 10 ml BHI broth tubes to make a fruit solution of 5% (w/v). E. coli O157:H7 was inoculated into fruit solutions at 2 log cfu/mL. After incubation at 37 °C for 24 h, samples were serially diluted 10 folds. The proper diluent was spread-plated on TSA in duplicate. After incubation at 35 °C for 24 h, viable cell counts were obtained. The experiment was replicated three times in a randomized complete-block design. Results demonstrated that guava products (fruit, juice, and leaf extracts) significantly reduced survival and growth of the tested foodborne pathogen strains. Water extract showed the highest antimicrobial activity, followed by methanol and hexane. These results indicate guava extracts are a potential antimicrobial agent to ensure food safety.

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Prevalence, Phylogroups and Antimicrobial Susceptibility of Escherichia coli Isolates from Food Products

Antibiotics ◽

10.3390/antibiotics10111291 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1291

Author(s):

Babak Pakbin ◽

Samaneh Allahyari ◽

Zahra Amani ◽

Wolfram Manuel Brück ◽

Razzagh Mahmoudi ◽

...

Keyword(s):

Foodborne Pathogen ◽

Raw Milk ◽

Resistance Pattern ◽

Surveillance Systems ◽

Drug Resistant ◽

Global Public Health ◽

Ground Meat ◽

Phylogenetic Groups ◽

Safety Control ◽

E Coli

The emergence of multi-drug resistant E. coli is an important matter of increasing considerable concern to global public health. The aim of this study was to investigate the incidence, antibiotic resistance pattern and phylogroups of E. coli isolates obtained from raw milk, vegetable salad and ground meat samples collected from Qazvin Province (Iran). Culture-based techniques, Kirby-Bauer disk diffusion susceptibility testing and PCR assays were used to determine the incidence rate, antimicrobial resistance pattern and phylogenetic groups of the E. coli isolates. The E. coli isolates were highly resistant to amoxicillin (79.1%), trimethoprim-sulfamethoxazole (70.8%), amoxicillin-clavulanic acid (62.5%), tetracycline (54.1%), chloramphenicol (54.1%), nitrofurantoin (54.1%), ampicillin (45.8%), streptomycin (45.8%), and kanamycin (33.3%); and completely susceptible to norfloxacin and azithromycin and 70.8% of the isolates were multi-drug resistant. Most E. coli isolates (46%) belonged to phylogroup A. Novel, practical, efficient food safety control and surveillance systems of multi-drug resistant foodborne pathogens are required to control the foodborne pathogen contamination.

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Prevalence of Pathogens and Indicator Organisms in Home Kitchens and Correlation with Unsafe Food Handling Practices and Conditions

Journal of Food Protection ◽

10.4315/0362-028x.jfp-16-354 ◽

2017 ◽

Vol 80 (4) ◽

pp. 590-597 ◽

Cited By ~ 9

Author(s):

Patricia A. Borrusso ◽

Jennifer J. Quinlan

Keyword(s):

Foodborne Pathogens ◽

Foodborne Pathogen ◽

Fecal Coliforms ◽

Indicator Organisms ◽

Food Handling ◽

E Coli ◽

Handling Practices ◽

Food Handling Practices ◽

Multiple Pathogens

ABSTRACT Despite education efforts, consumers often practice unsafe food handling and storage behaviors. Little is known about how these unsafe practices contribute to contamination of the home kitchen with foodborne pathogens. In addition, only a limited number of studies have examined the role of the kitchen as a reservoir for pathogens. The purpose of this study was to characterize microbial contamination and foodborne pathogens found in home kitchens and determine whether contamination was significantly associated with unsafe or unsanitary conditions observed in the kitchen. Swab samples were collected from food contact and preparation surfaces in homes (n = 100) in Philadelphia, PA. The samples were tested for coliforms, fecal coliforms, Escherichia coli, Staphylococcus aureus, Salmonella, Campylobacter, and Listeria. Fecal coliforms were found in 44% of homes (most often in samples from kitchen sinks, sponges, and dishcloths), and E. coli was found in 15% of homes (mostly in samples from kitchen sinks). Nearly half (45%) of the homes tested positive for a foodborne pathogen, and 12% had multiple pathogens present in the kitchen. S. aureus was isolated from 39% of homes, most often from countertops and refrigerator door handles. Listeria spp., including L. monocytogenes and L. innocua, were present in 15% of homes, most often in samples from refrigerator meat drawers. C. jejuni was isolated from 3% of homes. Contamination with Listeria was significantly associated with higher refrigerator temperatures. The contamination of surfaces with fecal coliforms and S. aureus was significantly associated with a lack of cleaning materials: dish soap and paper or cloth towels in the kitchen, and any type of towel in the nearest bathroom. The contamination of a sponge or dishcloth with either fecal coliforms or S. aureus was predictive of other surfaces in the kitchen having the same contamination, indicating that sponges and dishcloths are both reservoirs and vectors for bacteria in the kitchen.

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Bacterial Quality and Prevalence of Foodborne Pathogens in Edible Offal from Slaughterhouses in Korea

Journal of Food Protection ◽

10.4315/0362-028x.jfp-15-251 ◽

2016 ◽

Vol 79 (1) ◽

pp. 163-168 ◽

Cited By ~ 4

Author(s):

MIN CHAN IM ◽

KWANG WON SEO ◽

DONG HWA BAE ◽

YOUNG JU LEE

Keyword(s):

Foodborne Pathogens ◽

Hazard Analysis ◽

Control Point ◽

Foodborne Pathogen ◽

Microbiological Quality ◽

Point System ◽

Microbial Quality ◽

E Coli ◽

Critical Control Point

ABSTRACT Edible offal meats have recently received significant attention worldwide. However, studies evaluating the microbial quality of diverse edible offal and specifically investigating contamination by pathogens that cause foodborne illnesses are rare. Our study was conducted to investigate the microbiological quality of six kinds of edible offal produced from 11 pigs and 8 cattle slaughterhouses in the Republic of Korea and the prevalence of pathogenic microorganisms such as Salmonella, Clostridium perfringens, Staphylococcus aureus, and Escherichia coli O157:H7 in these products. The values for aerobic plate counts, coliform counts, and E. coli counts in red offal were 1.00 to 6.70, 0 (below 10 CFU) to 4.78, and 0 to 4.00 log CFU/g, respectively. For green offal, the values were 3.00 to 7.00, 1.48 to 6.30, and 0 to 6.00 log CFU/g, respectively. The most frequently detected foodborne pathogen was Salmonella (23.8% prevalence in pig offal and 7.1% prevalence in cattle offal), followed by C. perfringens (11.1 and 7.1%, respectively) and S. aureus (12.7 and 2.4%, respectively). None of the offal samples tested positive for E. coli O157:H7. Considering the microbial quality of offal from Korean slaughterhouses and the prevalence of foodborne pathogens in this material, more refined hygienic standards such as a hazard analysis critical control point system for processing, packing, and transporting edible offal are necessary for preventing further contamination.

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Comparison of the Difco EZ Coli™ Rapid Detection System and Petrifilm™ Test Kit-HEC for Detection of Escherichia coli O157:H7 in Fresh and Frozen Ground Beef

Journal of Food Protection ◽

10.4315/0362-028x-61.1.110 ◽

1998 ◽

Vol 61 (1) ◽

pp. 110-112 ◽

Cited By ~ 6

Author(s):

JON-MIKEL WOODY ◽

JOHN A. STEVENSON ◽

RICHARD A. WILSON ◽

STEPHEN J. KNABEL

Keyword(s):

Escherichia Coli ◽

Rapid Detection ◽

Detection System ◽

Screening Method ◽

Frozen Storage ◽

Ground Beef ◽

Escherichia Coli O157 ◽

Enrichment Broth ◽

E Coli ◽

Test Kit

The Difco EZ Coli™ Rapid Detection System was compared to the 3M Petrifilm™ method for detection of Escherichia coli O157:H7 in raw ground beef. Raw meatballs (25 g) were inoculated with 10 to 15 cells of Escherichia coli O157:H7, stored for various times and at different temperatures, and then stomached for 2 min in 225 ml of EZ Coli™ enrichment broth, which was then incubated at 42°C for 18 to 24 h. A 1-ml sample of the enrichment broth was loaded into the top of the detector tips and the remaining EZ Coli™ broth held at 35°C before streaking onto MacConkey sorbitol agar and tryptic soy agar with yeast extract. A duplicate set of meatballs were tested using the 3M Petrifilm™ Test Kit-HEC for hemorrhagic Escherichia coli O157:H7. In this method raw meatballs (25 g) were enriched for 6 h in modified EC broth containing novobiocin at 37°C prior to inoculation of the Petrifilm™ E. coli Count Plates, which were incubated at 42°C for 18 h. The immunoblot ELISA was performed following this incubation. Presumptive positive isolates from both methods were confirmed using Oxoid E. coli Latex Agglutination and Difco Pasco ID Tripanels. Both methods permitted detection of 10 to 15 cells of E. coli O157:H7 per ml (i) immediately following inoculation, (ii) after 3 days of refrigerated storage at 8°C, and (iii) after 30 days in frozen storage at −20°C. The Difco EZ Coli™ Detection System proved to be a simpler and faster screening method with identification of negative and presumptive positive samples within 15 to 18 h

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Foodborne Pathogen Assessment in Raw Milk Cheeses

International Journal of Food Science ◽

10.1155/2020/3616713 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5

Author(s):

Nicola Costanzo ◽

Carlotta Ceniti ◽

Adriano Santoro ◽

Maria Teresa Clausi ◽

Francesco Casalinuovo

Keyword(s):

Listeria Monocytogenes ◽

Foodborne Pathogens ◽

Foodborne Pathogen ◽

Bacterial Count ◽

Raw Milk ◽

Good Manufacturing Practice ◽

Staphylococcal Enterotoxin ◽

Total Bacterial Count ◽

E Coli ◽

Coagulase Positive Staphylococci

General hygienic parameters and selected foodborne pathogens in raw milk cheeses at the retail level were evaluated. A total of 245 raw milk cheese samples were analysed for total bacterial count, Enterobacteriaceae, E. coli, Salmonella spp., Listeria monocytogenes, coagulase-positive Staphylococci, and staphylococcal enterotoxin. Results showed only 3 samples that were not compliant with European rules on staphylococcal enterotoxin, but coagulase-positive Staphylococci were evidenced in all samples tested. Salmonella spp. and Listeria monocytogenes were never detected whereas E. coli was evidenced in 20 samples. Results suggest a need for improvement of good manufacturing practice and milking operation.

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