scholarly journals Effect of sequential presoaking and chlorine dioxide treatment on the inactivation of pathogenic Escherichia coli and Salmonella spp. on sprout seeds

2020 ◽  
Vol 63 (1) ◽  
Author(s):  
Nguyen Bao Hung ◽  
Woon-Ra Park ◽  
Bohyun Yun ◽  
Dong Cheol Seo ◽  
Won-Il Kim ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Chlorine Dioxide ◽  
Treatment Time ◽  
Germination Rate ◽  
Foodborne Diseases ◽  
Salmonella Spp ◽  
E Coli ◽  
Pathogenic Escherichia Coli ◽  
Seed Disinfection ◽  
Alfalfa Seeds

Abstract This study was conducted to evaluate the effect of sequential presoaking and chlorine dioxide (ClO2) on the reduction of pathogenic Escherichia coli and Salmonella spp. in alfalfa. When unsoaked and presoaked alfalfa were exposed to 200 ppm ClO2 for 15 min, the population of E. coli and Salmonella spp. on presoaked seeds reduced more than those on unsoaked seeds by 2.07 and 1.43 log CFU g−1 (p < 0.05), respectively. To determine the optimal concentration and treatment time to reduce pathogenic E. coli and Salmonella spp. in alfalfa seeds immersed in water for 5 h, presoaked seeds were exposed to four different concentrations of ClO2 (50, 100, 150, and 200 ppm) for 15, 30, 45, and 60 min. The most effective condition to eliminate E. coli and Salmonella spp. from alfalfa seeds was sequential immersion in water for 5 h and 200 ppm ClO2 treatment for 1 h. After the optimal condition was applied to eight kinds of sprout seeds, the pathogens were completely inactivated in all seeds, except radish seeds. Growth of pathogenic E. coli and Salmonella spp. during sprouting after ClO2 treatment of alfalfa seeds was also completely inactivated. However, the germination rate of seeds did not significantly decrease after ClO2 treatment. In addition, ClO2 residues were not present in any sprout during 3 days of cultivation. These results demonstrated that sequential presoaking and 200 ppm ClO2 treatment is the optimal seed disinfection treatment to prevent foodborne diseases associated with sprout consumption.

Response Surface Modeling for the Inactivation of Escherichia coli O157:H7 on Green Peppers (Capsicum annuum L.) by Chlorine Dioxide Gas Treatments†

2001 ◽  
Vol 64 (8) ◽  
pp. 1128-1133 ◽  
Author(s):  
Y. HAN ◽  
J. D. FLOROS ◽  
R. H. LINTON ◽  
S. S. NIELSEN ◽  
P. E. NELSON
Keyword(s):  
Escherichia Coli ◽  
Predictive Model ◽  
Response Surface ◽  
Chlorine Dioxide ◽  
Treatment Time ◽  
Membrane Surface ◽  
Escherichia Coli O157 ◽  
Gas Concentration ◽  
E Coli ◽  
Log Reduction

The effects of chlorine dioxide (ClO2) gas concentration (0.1 to 0.5 mg/liter), relative humidity (RH) (55 to 95%), treatment time (7 to 135 min), and temperature (5 to 25°C) on inactivation of Escherichia coli O157:H7 on green peppers were studied using response surface methods. A four-factor, central, composite, rotatable design was used. The microbial log reduction was measured as a response. A direct membrane-surface-plating method with tryptic soy agar and sorbitol Mac-Conkey agar was used to resuscitate and enumerate ClO2-treated E. coli O157:H7 cells. The statistical analysis and the predictive model developed in this study suggest that ClO2 gas concentration, treatment time, RH, and temperature all significantly (P &lt; 0.01) increased the inactivation of E. coli O157:H7. ClO2 gas concentration was the most important factor, whereas temperature was the least significant. The interaction between ClO2 gas concentration and RH indicated a synergistic effect. The predictive model was validated, and it could be used to determine effective ClO2 gas treatments to achieve a 5-log reduction of E. coli O157:H7 on green peppers.

Combination Treatments for Killing Escherichia coli O157:H7 on Alfalfa, Radish, Broccoli, and Mung Bean Seeds

2009 ◽  
Vol 72 (3) ◽  
pp. 631-636 ◽  
Author(s):  
M. L. BARI ◽  
D. NEI ◽  
K. ENOMOTO ◽  
S. TODORIKI ◽  
S. KAWAMOTO
Keyword(s):  
Escherichia Coli ◽  
Heat Treatment ◽  
Mung Bean ◽  
Germination Rate ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Dry Heat ◽  
Pathogen Populations ◽  
Dry Heat Treatment ◽  
Alfalfa Seeds

In this study, the effectiveness of prolonged dry-heat treatment (50°C) alone or in combination with chemical treatments (1% oxalic acid, 0.03% phytic acid, 50% ethanol, electrolyzed acidic water, and electrolyzed alkaline water) in eliminating Escherichia coli O157:H7 on laboratory-inoculated alfalfa, radish, broccoli, and mung bean seeds was compared with that of dry-heat treatment in combination with irradiation treatment. Dry-heat treatment for 17 or 24 h alone could reduce E. coli O157:H7 numbers to below detectable levels in radish, broccoli, and alfalfa seeds, but was unable to reduce the pathogen numbers to below the detectable level in mung bean seeds. In addition, dry-heat treatment for 17 h plus sanitizer treatments were effective in greatly reducing pathogen populations on radish, broccoli, and alfalfa seeds, without compromising the quality of the sprouts, but these treatments did not eliminate the pathogen from radish and alfalfa seeds. Seventeen hours of dry heat followed by a 1.0-kGy dose of irradiation completely eliminated E. coli O157:H7 from radish and mung bean seeds, whereas only a minimum radiation dose of 0.25 kGy was required to completely eliminate the pathogen from broccoli and alfalfa seeds. Dry heat in combination with radiation doses of up to 1.0 kGy did not negatively impact the seed germination rate or length of alfalfa, broccoli, and radish seeds or the length of alfalfa, broccoli, and radish sprouts, but did decrease the length of mung bean sprouts.

Effect of Escherichia Coli Infection on Metabolism of Dietary Protein in Intestine

2020 ◽  
Vol 21 (8) ◽  
pp. 772-776
Author(s):  
Xiao-Pei Peng ◽  
Wei Ding ◽  
Jian-Min Ma ◽  
Jie Zhang ◽  
Jian Sun ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Intestinal Tract ◽  
Effector Proteins ◽  
Physical Injury ◽  
Dietary Proteins ◽  
Pathogenic Role ◽  
E Coli ◽  
Low Protein ◽  
Pathogenic Escherichia Coli ◽  
Escherichia Coli Infection

Dietary proteins are linked to the pathogenic Escherichia coli (E. coli) through the intestinal tract, which is the site where both dietary proteins are metabolized and pathogenic E. coli strains play a pathogenic role. Dietary proteins are degraded by enzymes in the intestine lumen and their metabolites are transferred into enterocytes to be further metabolized. Seven diarrheagenic E. coli pathotypes have been identified, and they damage the intestinal epithelium through physical injury and effector proteins, which lead to inhibit the digestibility and absorption of dietary proteins in the intestine tract. But the increased tryptophan (Trp) content in the feed, low-protein diet or milk fractions supplementation is effective in preventing and controlling infections by pathogenic E. coli in the intestine.

scholarly journals Avian Pathogenic Escherichia coli (APEC): An Overview of Virulence and Pathogenesis Factors, Zoonotic Potential, and Control Strategies

Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 467
Author(s):  
Dipak Kathayat ◽  
Dhanashree Lokesh ◽  
Sochina Ranjit ◽  
Gireesh Rajashekara
Keyword(s):  
Escherichia Coli ◽  
Current Status ◽  
Neonatal Meningitis ◽  
Clear Understanding ◽  
Zoonotic Potential ◽  
Secretion Systems ◽  
Avian Pathogenic Escherichia Coli ◽  
E Coli ◽  
Pathogenic Escherichia Coli ◽  
Tract Infections

Avian pathogenic Escherichia coli (APEC) causes colibacillosis in avian species, and recent reports have suggested APEC as a potential foodborne zoonotic pathogen. Herein, we discuss the virulence and pathogenesis factors of APEC, review the zoonotic potential, provide the current status of antibiotic resistance and progress in vaccine development, and summarize the alternative control measures being investigated. In addition to the known virulence factors, several other factors including quorum sensing system, secretion systems, two-component systems, transcriptional regulators, and genes associated with metabolism also contribute to APEC pathogenesis. The clear understanding of these factors will help in developing new effective treatments. The APEC isolates (particularly belonging to ST95 and ST131 or O1, O2, and O18) have genetic similarities and commonalities in virulence genes with human uropathogenic E. coli (UPEC) and neonatal meningitis E. coli (NMEC) and abilities to cause urinary tract infections and meningitis in humans. Therefore, the zoonotic potential of APEC cannot be undervalued. APEC resistance to almost all classes of antibiotics, including carbapenems, has been already reported. There is a need for an effective APEC vaccine that can provide protection against diverse APEC serotypes. Alternative therapies, especially the virulence inhibitors, can provide a novel solution with less likelihood of developing resistance.

scholarly journals Molecular characterization and antimicrobial resistance of potentially human‐pathogenic Escherichia coli strains isolated from riding horses

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Pouya Reshadi ◽  
Fatemeh Heydari ◽  
Reza Ghanbarpour ◽  
Mahboube Bagheri ◽  
Maziar Jajarmi ◽  
...  
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Health Concern ◽  
Zoonotic Potential ◽  
Drug Resistant ◽  
Public Health Concern ◽  
E Coli ◽  
Pathogenic Escherichia Coli ◽  
Amoxicillin Clavulanic Acid

Abstract Background Transmission of antimicrobial resistant and virulent Escherichia coli (E. coli) from animal to human has been considered as a public health concern. This study aimed to determine the phylogenetic background and prevalence of diarrheagenic E. coli and antimicrobial resistance in healthy riding-horses in Iran. In this research, the genes related to six main pathotypes of E. coli were screened. Also, genotypic and phenotypic antimicrobial resistance against commonly used antibiotics were studied, then phylo-grouping was performed on all the isolates. Results Out of 65 analyzed isolates, 29.23 % (n = 19) were determined as STEC and 6.15 % (n = 4) as potential EPEC. The most prevalent antimicrobial resistance phenotypes were against amoxicillin/clavulanic acid (46.2 %) and ceftriaxone (38.5 %). blaTEM was the most detected resistance gene (98.4 %) among the isolates and 26.15 % of the E. coli isolates were determined as multi-drug resistant (MDR). Three phylo-types including B1 (76.92 %), A (13.85 %) and D (3.08 %) were detected among the isolates. Conclusions Due to the close interaction of horses and humans, these findings would place emphasis on the pathogenic and zoonotic potential of the equine strains and may help to design antimicrobial resistance stewardship programs to control the dissemination of virulent and multi-drug resistant E. coli strains in the community.

scholarly journals Potentially Human-Pathogenic Escherichia coli O26 in Norwegian Sheep Flocks

2011 ◽  
Vol 77 (14) ◽  
pp. 4949-4958 ◽  
Author(s):  
C. Sekse ◽  
M. Sunde ◽  
B.-A. Lindstedt ◽  
P. Hopp ◽  
T. Bruheim ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Variable Number Tandem Repeat ◽  
Variable Number ◽  
Human Pathogens ◽  
Content Type ◽  
Representative Sampling ◽  
E Coli ◽  
Pathogenic Escherichia Coli ◽  
Close Relationship ◽  
Large Survey

ABSTRACTA national survey ofEscherichia coliO26 in Norwegian sheep flocks was conducted, using fecal samples to determine the prevalence. In total, 491 flocks were tested, andE. coliO26 was detected in 17.9% of the flocks. One hundred forty-twoE. coliO26 isolates were examined for flagellar antigens (H typing) and four virulence genes, includingstxandeae, to identify possible Shiga toxin-producingE. coli(STEC) and enteropathogenicE. coli(EPEC). Most isolates (129 out of 142) were identified asE. coliO26:H11. They possessedeaeand may have potential as human pathogens, although only a small fraction were identified as STEC O26:H11, giving a prevalence in sheep flocks of only 0.8%. Correspondingly, the sheep flock prevalence of atypical EPEC (aEPEC) O26:H11 was surprisingly high (15.9%). The genetic relationship between theE. coliO26:H11 isolates was investigated by pulsed-field gel electrophoresis (PFGE) and multilocus variable number tandem repeat analysis (MLVA), identifying 63 distinct PFGE profiles and 22 MLVA profiles. Although the MLVA protocol was less discriminatory than PFGE and a few cases of disagreement were observed, comparison by partition mapping showed an overall good accordance between the two methods. A close relationship between a few isolates of aEPEC O26:H11 and STEC O26:H11 was identified, but all theE. coliO26:H11 isolates should be considered potentially pathogenic to humans. The present study consisted of a representative sampling of sheep flocks from all parts of Norway. This is the first large survey of sheep flocks focusing onE. coliO26 in general, including results of STEC, aEPEC, and nonpathogenic isolates.

Impact of Interventions on the Survival of Salmonella enterica I 4,[5],12:I:- in Pork

2021 ◽  
Author(s):  
Braden Wiser ◽  
S.E. Niebuhr ◽  
James Dickson
Keyword(s):  
Escherichia Coli ◽  
Heat Resistance ◽  
Mixed Culture ◽  
Refrigerated Storage ◽  
Unique Challenge ◽  
E Coli ◽  
Pork Industry ◽  
Pathogenic Escherichia Coli ◽  
Ground Pork ◽  
Salmonella Serovars

A mixed culture of different isolates of Salmonella serovar I 4,[5], 12:i:- was compared to a mixed culture of reference Salmonella serovars as well as non-pathogenic Escherichia coli surrogates.. The two groups of Salmonella were compared for their resistance to commonly used pork carcass interventions, survival in ground pork and thermal resistance in ground pork. There were no observed differences between the response of the two different groups of Salmonella serovars and the non-pathogenic E. coli surrogates within intervention type.  There were no observed differences in the recovery and survival of the two different groups of Salmonella serovars in pork which had been treated with interventions, ground and stored at 5 o C for two weeks. Finally, there were no observed differences in heat resistance between the two different groups of Salmonella serovars in ground pork which had been treated with interventions, ground and stored at 5 o C for two weeks. However, there were observed differences in heat resistance in both groups of Salmonella serovars associated with refrigerated storage. The heat resistance of both groups of Salmonella serovars decreased after refrigerated storage. The results of these experiments demonstrate that there were no observed differences between the responses of Salmonella serovar I 4,[5], 12:i:- when compared to the reference Salmonella serovars to commonly used interventions in the pork industry, and therefore do not present a unique challenge to the pork industry.

Reduction of Escherichia coli O157:H7 Counts on Whole Fresh Apples by Treatment with Sanitizers

2000 ◽  
Vol 63 (6) ◽  
pp. 703-708 ◽  
Author(s):  
MARCY A. WISNIEWSKY ◽  
BONITA A. GLATZ ◽  
MARK L. GLEASON ◽  
CHERYLL A. REITMEIER
Keyword(s):  
Escherichia Coli ◽  
Chlorine Dioxide ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Escherichia Coli O157 ◽  
Peroxyacetic Acid ◽  
Water Control ◽  
Buffer Solution ◽  
E Coli ◽  
Log Reduction

The objectives of this study were to determine if washing of whole apples with solutions of three different sanitizers (peroxyacetic acid, chlorine dioxide, or a chlorine-phosphate buffer solution) could reduce a contaminating nonpathogenic Escherichia coli O157:H7 population by 5 logs and at what sanitizer concentration and wash time such a reduction could be achieved. Sanitizers were tested at 1, 2, 4, 8, and 16 times the manufacturer's recommended concentration at wash times of 5, 10, and 15 min. Whole, sound Braeburn apples were inoculated with approximately 1 × 108 or 7 × 106 CFU per apple, stored for 24 h, then washed with sterile water (control) or with sanitizers for the prescribed time. Recovered bacteria were enumerated on trypticase soy agar. Washing with water alone reduced the recoverable population by almost 2 logs from the starting population; this can be attributed to physical removal of organisms from the apple surface. No sanitizer, when used at the recommended concentration, reduced the recovered E. coli population by 5 logs under the test conditions. The most effective sanitizer, peroxyacetic acid, achieved a 5-log reduction when used at 2.1 to 14 times its recommended concentration, depending on the length of the wash time. The chlorine-phosphate buffer solution reduced the population by 5 logs when used at 3 to 15 times its recommended concentration, depending on wash time. At no concentration or wash time tested did chlorine dioxide achieve the 5-log reduction.

scholarly journals Prevalence and molecular characterisation of shiga-toxin-producing Escherichia coli in raw milk cheeses from Lazio region, Italy

2016 ◽  
Vol 5 (1) ◽  
Author(s):  
Selene Marozzi ◽  
Paola De Santis ◽  
Sarah Lovari ◽  
Roberto Condoleo ◽  
Stefano Bilei ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Raw Milk ◽  
Foodborne Diseases ◽  
Control Plan ◽  
Lazio Region ◽  
Standard Methods ◽  
E Coli ◽  
Regional Control ◽  
Unpasteurized Milk

In recent years, the incidence of foodborne diseases caused by shiga toxin-producing <em>Escherichia coli</em> (STEC) has increased globally. For this reason, within the specific regional control plan for the detection of STEC in food products in Italy, the presence of STEC in unpasteurized milk cheeses was investigated. In total 203 samples obtained from March 2011 to December 2013 were analysed, with two standard methods (ISO 16654:2001 and ISO 13136:2012). Two strains of <em>E. coli</em> O157 were isolated (2/161, 1.2%) but did not carry any virulence-associated genes and 22 <em>stx</em>-positive samples (22/146, 15.1%) were detected in enrichment cultures, mostly from ovine cheeses. Only two strains isolated from different ovine cheeses carried <em>stx</em> gene and none of these was <em>eae</em>-positive. This study confirms the presence of <em>stx</em>-positive <em>E. coli</em> and suggests that this type of food cannot be excluded as a potential vehicle of STEC.

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