E. coli O157:H7 + S. Typhimurium

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Survival characteristics of E  coli O157:H7, S  typhimurium and S  aureus during kefir fermentation

Survival characteristics of E coli O157:H7, S typhimurium and S aureus during kefir fermentation

in meat, with pH adjusted with 50% lactic acid and fermented at 22°C. The growth and survival of E. coli O157:H7 during fermentation of kefir is shown in Table 1. Both EC-1 and EC-2 samples show similar growth patterns during fermentation. EC-1 grew from 2.29 ± 0.02 log CFU/ml to 4.13 ± 0.18 log CFU/ml whereas EC-2 grew from 3.22 ± 0.04 log CFU/ml to 6.78 ± 0.99 log CFU/ ml. Similarly, the populations of E. coli O157:H7 strains in both samples were doubled in log units during the same period. During fermenta- tion, pH of kefir decreased from 6.7 to 4.6 (Figure 1). In spite of this decrease in pH, viable populations of E. coli O157:H7 strains were increased. As seen in Table 1, the populations of the E. coli O157:H7 strains in both EC-1 and EC-2 significantly in- creased during the fermentation period (P < 0.05). This shows that stationary-phase strains of E. coli O157:H7 are acid tolerant and can survive dur- ing acid fermantation. Stationary-phase cells of E. coli O157:H7 are more resistant to acid than log-phase cells. Similiar findings of E. coli O157:H7 survival during fermentation of yoghurt were reported by Ogwaro et al. (2002). Tsegaye et al. (2004) found that E. coli O157:H7 strains can
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Aptasensors for rapid detection of Escherichia coli O157:H7 and Salmonella typhimurium

Aptasensors for rapid detection of Escherichia coli O157:H7 and Salmonella typhimurium

Diarrheal diseases caused by a range of enteropathogenic bacteria represent a major health threat in developing countries. According to the data from the World Health Organization, there are almost two million deaths per year (1.7-2.5 million deaths) caused by diarrhea. Emer- ging and known enteropathogenic bacteria are, among others, Escherichia coli (E. coli) O157:H7 and Salmonella typhimurium (S. typhimurium). E. coli O157:H7 has been recognized as a major intestinal flora for a long time since it was detected as the pathogen that causes foodborne disease outbreaks in the USA [1,2]. In the past decades, E. coli O157:H7 has received tremendous attention, because it becomes an important pathogenic cause for several severe illnesses in human beings such as gastrointestinal disease and bloody diarrhea which is a root cause of hemolytic uremic syndrome [3]. In addition, the incidence of S. typhimurium outbreaks is on the rise. In 2010, the outbreak of S. typhimurium
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Antimicrobial effects of curcumin against L. monocytogenes S. aureus S. Typhimurium and E. coli O157:H7 pathogens in minced meat

Antimicrobial effects of curcumin against L. monocytogenes S. aureus S. Typhimurium and E. coli O157:H7 pathogens in minced meat

ABSTRACT: The aim of this study was to determine the antimicrobial efficacy of curcumin, one of the active components of the Curcuma longa (turmeric) plant, against food pathogens in a minced meat medium. Salmo- nella Typhimurium ATCC 14028, Listeria monocytogenes ATCC 7644, Escherichia coli O157:H7 ATCC 33150 and S. aureus ATCC 25923 strains were used as food pathogens. Minimum inhibitory concentrations (MICs) were determined using the macrodilution method. MIC values for curcumin were found to be 125 µg/ml for L. mono- cytogenes and S. aureus, and 250 µg/ml for S. Typhimurium and E. coli O157:H7. Food pathogens were added to the minced meat at 10 4 CFU/g (including the control group) and curcumin at doses of 0.5%, 1% and 2% (except
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Serotype O157:H7 Escherichia coli from bovine and meat sources

Serotype O157:H7 Escherichia coli from bovine and meat sources

coli serotype 0157:H7 possessed a large-molecular-size plasmid 53 to 64 MDa but only 5 of them possessed the ability to adhere to HEp-2 and Intestine 407 cells indicates that in vitro ex[r]

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Disinfection Treatment of Heated Scallop Shell Powder on Biofilm of Escherichia coli ATCC 25922 Surrogated for  E  coli O157:H7

Disinfection Treatment of Heated Scallop Shell Powder on Biofilm of Escherichia coli ATCC 25922 Surrogated for E coli O157:H7

cells shifts to the right and has a gentler slope than that of the planktonic cells. In this case, the conductivity changes are contributed by the bacterial metabolism of both biofilm and planktonic cells. The planktonic cells in the RABIT tubes were derived from attached cells. As the cells proliferated on the glass plate, some of them likely detached from the biofilm structure, becoming planktonic. These dynamics are reflected in the calibra- tion curves, which linearly correlate with the initial number of cells inoculated on the glass plate. As men- tioned in Section 3, for a given TTD, the calibration curve derived from the planktonic cells underestimates the population of E. coli cells in the biofilm by two or three orders of magnitude. For this reason, the viable cell counts in biofilms exposed to HSSP were estimated from the attached-cell calibration curve.
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Chitosan-Based Intranasal Vaccine against Escherichia coli O157:H7

Chitosan-Based Intranasal Vaccine against Escherichia coli O157:H7

Background: Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is an infectious zoonotic pathogen causing human infections. These infections, in some cases, can lead to hemolytic uremic syndrome and its life-threatening complications and even death worldwide. The first intimate bacterial adhesion, intimin (I), with its own receptor translocated intimin receptor (Tir) and E. coli secreted protein A, acting as Tir conduit, are highly immunogenic proteins for vaccine development against E. coli O157:H7. Methods: A chimeric trivalent recombinant protein was previously found to be a suitable strategy for developing vaccines against E. coli O157:H7. In this study, the recombinant EIT (rEIT) was used to design a protective EHEC nasal nanovaccine. Chitosan and its water-soluble derivative, trimethylated chitosan (TMC), as muco-adhesive biopolymers, are good candidates for preparation of nanovaccines. Using the electrospraying technique, as a novel method, we could obtain particles of rEIT loaded with chitosan and TMC on a nanometer scale. Mice were immunized with intranasal administration or intrapretoneal injection of rEIT. Results: The rEIT-specific immune responses (IgG and IgA) were measured by indirect ELISA. Only nasal administration of chitosan electrospray and TMC formulation produced significant secretion IgA. Intranasal administration of nanovaccine reduced the duration of bacterial fecal shedding on mice challenged with E. coli O157:H7. Conclusion: Since development of mucosal vaccines for the prevention of infectious diseases requires efficient antigen delivery; therefore, this research could be a new strategy for developing vaccine against E. coli O157:H7. DOI: 10.7508/ibj.2016.02.005
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Characterization of a ViI like Phage Specific to Escherichia coli O157:H7

Characterization of a ViI like Phage Specific to Escherichia coli O157:H7

AG3 lie in the genes encoding their host-recognition elements – CBA120 orfs 210-213 (Table 2) – though there are clear relationships. Orfs 210, 212 and 213 encode spike proteins, as has been discussed for ViI [20]. The N-terminal 163 amino acids of the tail spikes encoded by CBA120 orfs 210 and 212 are very similar to each other and, from amino acid 23 on, to amino acids 248-490 of the orf 213 tail spike. From that point on, they diverge markedly. Much of the rest of orfs 210 and 212 show relationships to phage K1F, including its endosialidase region, and to podovirus EcoDS1 as well as to AG3 orf 207, while CBA120 orf 213 is more like AG3 orf 213 over most of its length. The conserved N- terminal segment of the three CBA120 tail spikes is also closely related (> 80%) to the N-terminal region of the published tail-spike protein of Salmonella enterica sero- var Typhimurium phage Det7, the first myovirus demonstrated to use a podovirus-like tail spike [36]; the authors determined that this region is what binds to the tail, and determined the crystal structure of the rest of the spike, which looks much like that of phage P22. (The still-unpublished full sequence of Det7 indicates that it is also a member of this family (Sherwood Cas- jens, personal communication)). It is also > 60% related to the same regions of the ViI 846 aa and 596 aa tail spikes. The region from aa 103 to 211 of CBA120 orf 210 shows 45% identity with aa 156 to 264 of the tail- spike gene of coliphage K1F, and similar strong identi- ties are seen between this region of K1F and the comparable regions of the gp 212 and 213 tailspikes. The N-terminal 225-amino acid extension on the spike encoded by orf 213 appears to be unique to the ViI group of phages; one possibility is that it is involved in transferring the signal to contract from that spike to the myovirus tail structure after the spikes bind. CBA120 orf 211 encodes a putative tail fiber, with its primary
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Bovine Immune Response to Shiga-Toxigenic Escherichia coli O157:H7

Bovine Immune Response to Shiga-Toxigenic Escherichia coli O157:H7

As previously postulated (31), the immunosuppressive ef- fects of STEC infections appeared to result from a prevention of the onset of an immune response rather than the downregu- lation of an established one. The development of an in vitro PBMC response was prevented when Stx2 was present at the time that the naı¨ve O157:H7 E. coli-specific immune cells were first stimulated by the initial inoculations (i.e., in calves initially inoculated with Stx2 ⫹ O157). In contrast, the Stx2 ⫹ O157 strain did not exert an immunosuppressive effect after the immune response was efficiently induced by two inoculations with Stx ⫺ O157. Calves initially inoculated with Stx ⫺ O157 showed a continued proliferative response that, similar to an anamnestic FIG. 4. Comparison over time of the lymphoproliferative responses to heat-killed Stx2 ⫹ E. coli O157:H7 bacteria (HK-O157) in calves inoculated with different E. coli strains. Calves were inoculated twice (on days 0 and 21) with Stx2 ⫹ E. coli O157:H7 strain 86-24 (Stx2 ⫹ ), non-Shiga-toxigenic E. coli O157:H7 strain 87-23 (Stx ⫺ ), or control E. coli O43:H28 strain 123 (Control) prior to a final challenge (at 7 weeks postinoculation) with Stx2 ⫹ E. coli O157:H7 strain 86-24. Results are shown as the means ( ⫾ standard errors of the means) of the SIs obtained with PBMCs from five calves per group. The index for an individual animal was determined by dividing the mean counts per minute for three wells stimulated with HK-O157 by the mean counts per minute for three wells of nonstimulated cells. Lymphoproliferative responses to ConA stimulation are shown in the insert. Data obtained with blood samples during weeks 1, 2, and 3, during weeks 4 and 6, and postchallenge (during weeks 7, 8 and 10) were combined within those respective groups.
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Detection of E. coli O157:H7 in Meat Using Polymerase Chain Reaction Method and Culture Method

Detection of E. coli O157:H7 in Meat Using Polymerase Chain Reaction Method and Culture Method

The present study is the first report on the E. coli O157:H7 contamination rate in meat in Kerman, Iran and suggests that the consumption of semi-cooked meat (especially beef and lamb) may contribute to the transmission of this pathogen to humans. Therefore, the precise monitoring and observance of health principles during slaughtering, transportation, and maintenance processes can reduce the transmission rate. More studies are recommended in other regions of Iran.

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Ethanolamine Influences Human Commensal Escherichia coli Growth, Gene Expression, and Competition with Enterohemorrhagic E  coli O157:H7

Ethanolamine Influences Human Commensal Escherichia coli Growth, Gene Expression, and Competition with Enterohemorrhagic E coli O157:H7

modified Eagle’s medium) (Fig. 1E; see also Fig. S1 in the supplemental material). To confirm that EA utilization by a human E. coli isolate was not unique to the HS isolate, we next examined EA utilization in E. coli Nissle, which was isolated from the stool of a German soldier during World War I (22, 23). Consistent with the HS data, Nissle grew and responded to EA (Fig. S2A to D). Altogether, these data indicate that human commensal E. coli strains have maintained the ability to sense and utilize EA as a metabolite and that EA enhances growth in the presence of alternative nitrogen sources (as would be found in the gut).
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Two putative MmpL homologs contribute to antimicrobial resistance and nephropathy of enterohemorrhagic E. coli O157:H7

Two putative MmpL homologs contribute to antimicrobial resistance and nephropathy of enterohemorrhagic E. coli O157:H7

Antibiotic resistance in E. coli, like in other bacte- ria, is promoted by various mechanisms, such as inac- tivation or degradation of antibiotic molecules, target alteration or overexpression, and decreased intra- cellular concentration of the antibiotic by reduced uptake or active efflux. Antibiotic efflux is one of the most common resistance mechanisms in bacteria, and is promoted by efflux pumps, among which are the resistance, nodulation, and cell division (RND) trans- porters. A correlation between the overexpression of a prototype of RND efflux pumps and induction of spontaneous mutations within crucial genes that con- fer permanent antibiotic resistance has been described [11]. The RND protein family is well defined in several organisms, most notably in Gram-negative bacteria, e.g., E. coli and Pseudomonas aeruginosa [12]. RND pumps are large proteins that may reach up to 1100 amino acids. The inner membrane pump is formed of 12 transmembrane domains (TMD), and two extra- cytoplasmic loops emerging from the first and second TMD as well as the seventh and the eighth TMD. The extra-cytoplasmic loops were proposed to determine the substrate specificity for the pump. The driving energy for RND mediated efflux is obtained from pro- ton motive force [13, 14].
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Isolation of Escherichia coli serotype O157:H7 and other Shiga like toxin producing E  coli from dairy cattle

Isolation of Escherichia coli serotype O157:H7 and other Shiga like toxin producing E coli from dairy cattle

In the Wisconsin investigation, fecal specimens were collected from 438 adult cows and 262 heifers and calves from the 2 farms with which the two HUS cases were associated, a dairy farm [r]

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Use of Ramification Amplification Assay for Detection of Escherichia coli O157:H7 and Other E  coli Shiga Toxin Producing Strains

Use of Ramification Amplification Assay for Detection of Escherichia coli O157:H7 and Other E coli Shiga Toxin Producing Strains

FIG. 1. Schematic representation of RAM assay. Target DNA, capture probe, C-probe, and paramagnetic bead are added to hybridization buffer to allow the formation of a hybrid complex. The hybrid is captured on a paramagnetic bead, allowing extensive washing to remove unbound C-probe and cellular components. The C-probe aligned on the target is linked together by a DNA ligase. RAM amplification is then carried out by the addition of forward ( ‹ ) and reverse ( ) primers and DNA polymerase ( F ). The forward primer bound to the C-probe is extended by the polymerase and continues after one round of synthesis by displacing the bound forward primer and its extended product, generating a long single-stranded DNA (ssDNA) with repeated sequence. With the reactions taking place, multiple reverse primers can bind to the nascent ssDNA as their binding sites become available. Each bound reverse primer will be extended and displace the downstream primers and their extended products. The forward primer binding sites of the displaced ssDNA are then available for the forward primer to bind and extend in a similar fashion, thus forming a large ramifying DNA complex. Finally, the RAM products are examined by gel electrophoresis after EcoRI digestion. (Inset) The C-probe hybridizes to the target through their complementary regions (f and g), and the sequence at the noncomplementary region (e) is generic for the binding of primers. The C-probe–target hybrid is captured on a paramagnetic bead (a) through the binding of the biotin moiety (c) on the capture probe (d) to the streptavidin (b) that the beads were coated with.
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ISOLATION AND MOLECULAR CHARACTERIZATION OF SHIGA TOXIN PRODUCING E  COLI O157:H7 IN RAW MILK USING mPCR

ISOLATION AND MOLECULAR CHARACTERIZATION OF SHIGA TOXIN PRODUCING E COLI O157:H7 IN RAW MILK USING mPCR

As a result of escalate in investigation of E. coli O157:H7 cases, considerable notice has been stated to establish approaches for detection of this pathogenic bacterium, including cultural isolation, DNA probes, serological tests and polymerase chain reaction (PCR) assays. PCR based approach are rapid, sensitive, specific and automated method for identification of microbial pathogens 12-13 . The use of milk and their products is locally increasing routinely. In view of the developing public knowledge regarding food quality and safety, awareness on milk microbial and chemical composition is of serious importance for additional evolving of its hygienic organizing into excellence consumer products. Yet, information on such manner is limited and scattered. Hence, the objectives of present study are to:
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Comparison between E  coli O157:H7 and Bifidobacterium spp  Activity in Almond Pudding Infant Supplemental Food

Comparison between E coli O157:H7 and Bifidobacterium spp Activity in Almond Pudding Infant Supplemental Food

Intestinal micro flora contains complex ecosystem with at least 50 bacteria genera and several hundreds of species. Comprising several hundred species, the major- ity of these bacteria reside in the colon and some are be- lieved to bring health and therapeutic benefits to the host. Bifodobacterium spp. is the safest genera and act as an opportunistic bacterium [11]. There is strong evidence of the effect of intestinal flora including bifidobacteria on human health. Bifidobacteria appear to reduce the inci- dence of traveler’s diarrhea. They are also reportedly antagonistic towards pathogens in adults and especially in infants [27,28]. Carbohydrates can be used as growth elements for probiotics inside the intestinal tract and it could indirectly inhibit the growth of food borne patho- gens including Escherichia coli, Campylobacter jejuni and Salmonella enteritidis [10]. Almond is a rich source of 22% protein and 21% carbohydrates including oligo- saccharides [29,30] oligosaccharide are a desirable sour- ces as a prebiotic to promote the growth of gastrointesti- nal beneficial microorganisms such as Bifidobacterium spp. and Lactobacilli [31,32] oligosaccharides are a third
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Isolation of Recombinant Antibodies against EspA and Intimin of Escherichia coli O157:H7

Isolation of Recombinant Antibodies against EspA and Intimin of Escherichia coli O157:H7

Both intimin and EspA polymorphisms have been reported. Using PCR-based analysis, intimin has been typed in A/E pro- ducing bacterial pathogens into ␣, ␤, ␥, and ␦ (1, 8). More recently, ␦ intimin was reclassified as ␤2 intimin and ε intimin described, as well as ␥ intimin being further divided into ␥1 and ␥2 intimins (27). There are at least 11 recognized intimin types (36). For EspA, antisera to this protein from EPEC O127:H6 were reported to cross-react with EspA filaments from O55:H6 but not filaments from other EPEC or EHEC strains, where- as antisera against EHEC O157:H7 cross-reacted against only O55:H7 (26). The monoclonal antibodies isolated against intimin in the present study were tested against outer mem- brane preparations from A/E lesion-producing bacterial patho- gens containing ␣ (O127:H6), ␤ (O111:NM), ␥1 (O157:H7), and ␤2 (O86:H34) intimins, as well as an O157:H7 intimin mutant (DM3) and a nonpathogenic K-12 E. coli strain. All of the anti-intimin antibodies tested (I1 to I6) were specific for ␥ intimin (E. coli O157:H7) and displayed no cross-reactivity to the other intimin types. The anti-EspA antibody E1 was simi- larly tested against whole-cell preparations of these E. coli strains. This scFv bound to EspA from EHEC O157:H7 (wild type and DM3) and EHEC O111:NM but not to EspA from EPEC O127:H6 or EPEC O86:H34. However, the presence of E1 epitopes in EspA from O127 and O86 cannot be ruled out since the protein appeared to be present in relatively low concentrations in whole-cell preparations, which may reflect the transient nature of the proteins’ expression. The polyclonal sera appeared to be much more sensitive than E1 in the West- ern blot analyses and could detect EspA in all of the patho- genic E. coli. The binding specificity of the polyclonal sera in the present study contrasts with the results for polyclonal sera against EHEC O157:H7 described by Neves et al. (26), which did not show cross-reactivity with EPEC O86:H34 or O127:H6 EspA filaments. Inconsistencies with the previous report may be due to the different presentation of epitopes within EspA filaments compared to denatured proteins on a Western blot or may highlight the occurrence of variations in EspA epitope recognition within different individual animals and/or immuni- zation regimes.
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Influence of Antibiotic, Acid, and Salt Stress on Resistance of Escherichia Coli O157:H7

Influence of Antibiotic, Acid, and Salt Stress on Resistance of Escherichia Coli O157:H7

Values are the means of triplicate replications. There was a 3-way interaction for strain*NaCl stress*acid stress (p<0.05), thus results are presented averaged across strain*acid stress (Table 5) and strain*NaCl stress (Table 6) and acid stress*NaCl stress (Table 7). Means followed by different letters are different (p<0.05). EHEC 1 and 2 refer to the 2 strains of E. coli O157:H7 evaluated in this study. NPEC –

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Escherichia coli O157:H7 restriction pattern recognition by artificial neural network

Escherichia coli O157:H7 restriction pattern recognition by artificial neural network

Samples. One hundred one isolates of E. coli O157:H7 and 99 isolates of non-O157:H7 E. coli were analyzed. Samples, collected over a period of several years, were provided by the Missouri, Texas, Kansas, Utah, and Pennsylvania Departments of Health and by Health Canada. The Canadian samples were specifically selected to include isolates from various parts of the country. All isolates were previously identified by standard biochemical means and serology and were reconfirmed by similar methods in our laboratory. All O157:H7 sam- ples were determined to be the same ribotype. Identified phage types included 1, 2, 8, 14, 23, and 32. Most isolates were derived from human diarrhea stool specimens, but some animal isolates were also included in the study (Table 1). Preparation of bacterial DNA. All isolates were cultured to log phase in brain heart infusion broth. An aliquot (1.3 ml of cell suspension) of each isolate was centrifuged at 12,000 3 g for 90 s, the supernatant was removed, and the pellet was washed twice in 1.0 ml of SE (75 mM NaCl, 25 mM EDTA, pH 8.0) buffer under the same centrifugation conditions. The optical density at 610 nm of the suspension was adjusted to 1.2 with SE diluent. The final suspension was mixed with an equal volume of warm 1% agarose prepared in modified TE buffer (10 mM Tris, 0.1 mM EDTA, pH 8.0), poured into molds (10 by 15 mm), and allowed to solidify. Agarose plugs were incubated overnight at 50 8 C in lysis buffer (50 mM Tris [pH 8.0], 50 mM EDTA [pH 8.0], 1% Sarcosine, 1 mg of proteinase K per ml). The plugs were rinsed briefly with deionized sterile water, TE buffer containing 15.0 m l of phenylmethylsulfonyl fluoride (17 mg/ml in isopropanol) per ml was added to tubes containing the plugs, and the samples were incubated at room temperature for 30 min. After a second wash with TE buffer containing phenylmethylsulfonyl fluoride, the blocks were again rinsed briefly with sterile deionized H 2 O, and the final four washes were in TE buffer for 30 min each. The
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Escherichia coli O157:H7 Biofilm Formation and Susceptibility to Disinfectants In Vitro and in Footbaths.

Escherichia coli O157:H7 Biofilm Formation and Susceptibility to Disinfectants In Vitro and in Footbaths.

Phenol works as a disinfectant by disrupting the cell membrane through inactivation of intracytoplasm enzymes. In low concentrations of phenol, cellular contents are released into the external media, whereas in high concentrations, phenol can inhibit permeases and cause lysis of the cell membrane (Joswick et al., 1971; Russell, 1983). When acting against E. coli O157:H7, phenol had an MIC of 2500 ppm in MHB, with a two-fold reduction to 1250 in M9 (Table 3.2). Similar to DDAC, at 0.5 × MIC of phenol, the bacteria were still capable of increasing in concentration throughout the duration of the assay (Figure 3.1D). Interestingly, at 1.0 × MIC, the concentration did not change, but remained fairly stable throughout 24 hours of exposure, indicating static activity. At 2 × MIC, the bacteria steadily decreased in concentration until they were killed by 4 hours of exposure. Previous studies have also evaluated the efficacy of commonly-used phenolic disinfectants in footbaths. These disinfectants tend to be ineffective at reducing bacterial load on the bottom of soles. In each study in which phenolic-based disinfectants were used in footbaths, there was no significant decrease or no detectable reduction of bacterial concentration on the soles of boots after stepping through the footbath (Hartmann, Dusick, and Young, 2013; Hornig et al., 2013).
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Antagonistic Activity of Probiotic Bacteria Isolated from Traditional Dairy Products against E. coli O157:H7

Antagonistic Activity of Probiotic Bacteria Isolated from Traditional Dairy Products against E. coli O157:H7

Lactobacillus and Bifidobacterium spp., the main genera of lactic acid bacteria (LAB), are the most commonly used probiotics (1). It should be noted that all of the lactic acid bacteria are not necessarily probiotic. The microorganisms known as probiotic are added to food products, when these foods are eaten, the microorganisms enter the bowel and exert their effect there. The trend of consuming probiotic foods has gradually increased in Europe, Asia, and North America, and today these food products are offered in the majority of supermarkets around the world (1, 2). The mechanism of action of probiotic bacteria on improve of health can be attributed to the following points: settlement and intestinal proliferation, regulation and control of microbial flora of the intestine, prevention from adhesion of pathogenic bacteria to the intestine's mucus and deactivating them, prevention and treatment of digestive disorders, activity against pathogenic agents, regulation of the enzymatic activity of bacteria, prevention from side effects of treatment with antibiotics, alteration of the proteins in diet, primary digestion of proteins, synthesis of vitamins, improvement of calcium absorption, metabolism of lactose and reduction of lactose intolerance, improvement of digestibility, enhancement of the nutritional value of food products, prevention from allergies, reduction of blood cholesterol, enhancing the power of the body's immune system, anticancer effects, and reduction of the growth of non-useful bacteria (3, 4, 5). This group of bacteria and their produced metabolites can have a wide range of therapeutic uses. The studies confirm the positive role of these bacteria in inhibition of pathogenic agents. E. coli O157:H7 is one the most important agents in the development of intestinal infections in human. These bacteria create a severe bloody diarrhea and some high-risk diseases such as hemolytic uremic syndrome (HUS), hemorrhagic colitis, and thrombotic thrombocytopenic purpura (TTP). E. coli O157:H7 has also been known as one of the pathogens that transfer from food and is one of the
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