Displaying publications 1 - 20 of 35 in total

Abstract:
Sort:
  1. A fluorescence quenching based gene assay for Escherichia coli O157:H7 using graphene quantum dots and gold nanoparticles
    Saad SM, Abdullah J, Rashid SA, Fen YW, Salam F, Yih LH
    Mikrochim Acta, 2019 11 19;186(12):804.
    PMID: 31745737 DOI: 10.1007/s00604-019-3913-8
    A fluorometric assay is described for highly sensitive quantification of Escherichia coli O157:H7. Reporter oligos were immobilized on graphene quantum dots (GQDs), and quencher oligos were immobilized on gold nanoparticles (AuNPs). Target DNA was co-hybridized with reporter oligos on the GQDs and quencher oligos on AuNPs. This triggers quenching of fluorescence (with excitation/emission peaks at 400 nm/530 nm). On introducing target into the system, fluorescence is quenched by up to 95% by 100 nM concentrations of target oligos having 20 bp. The response to the fliC gene of E. coli O157:H7 increases with the logarithm of the concentration in the range from 0.1 nM to 150 nM. The limit of detection is 1.1 ± 0.6 nM for n = 3. The selectivity and specificity of the assay was confirmed by evaluating the various oligos sequences and PCR product (fliC gene) amplified from genomic DNA of the food samples spiked with E. coli O157:H7. Graphical abstractSchematic representation of fluorometric assay for highly sensitive quantification of Escherichia coli O157:H7 based on fluorescence quenching gene assay for fliC gene of E. coli O157:H7.
    Matched MeSH terms: Escherichia coli O157/genetics; Escherichia coli O157/isolation & purification*
  2. Fulltext Antibacterial Activity of the Epidermal Mucus of Barbodes everetti
    JIAZHEN LIM, YANG LEE, BADIOZAMAN SULAIMAN, LESLEY MAURICE BILUNG, YEE LING CHONG
    Trends in Undergraduate Research, 2018;1(1):0-0.
    MyJurnal
    The epidermal mucus of fish contains antimicrobial agents that act as biological defence against disease. This study aims to identify antibacterial activity and protein concentration of epidermal mucus of Barbodes everetti, a Bornean endemic freshwater fish. The epidermal mucus was extracted with 3% acetic acid, 0.85% sodium chloride and crude solvents. The mucus activity against eight strains of human pathogenic bacteria, including Bacillus cereus ATCC 33019, Escherichia coli O157:H7, Listeria monocytogenes ATCC 7644, Pseudomonas aeruginosa ATCC 27853, Salmonella braenderup ATCC BAA 664, Salmonella typhimurium, Staphylococcus aureus ATCC 25933, and Vibrio cholerae, were tested. The acetic acid mucus extract of B. everetti was able to inhibit five strains of bacteria and show no activity toward E. coli O157:H7, B. cereus ATCC 33019 and L. monocytogenes ATCC 7644. Moreover, the highest protein concentration was quantified in crude extract, followed by aqueous and acetic acid extracts. This study provides a preliminary knowledge on the activity of epidermal mucus of B. everetti towards five out of the eight human pathogens tested, therefore it may contain potential sources of novel antibacterial components which could be further extracted for the production of natural antibiotics towards human-related pathogenic bacteria.
    Matched MeSH terms: Escherichia coli O157
  3. Antibacterial activity and mechanical properties of partially hydrolyzed sago starch-alginate edible film containing lemongrass oil
    Maizura M, Fazilah A, Norziah MH, Karim AA
    J Food Sci, 2007 Aug;72(6):C324-30.
    PMID: 17995673
    Edible films were prepared from a mixture of partially hydrolyzed sago starch and alginate (SA). Lemongrass oil (0.1% to 0.4%, v/w) and glycerol (0% and 20%, w/w) were incorporated in the films to act as natural antimicrobial agent and plasticizer, respectively. The films were characterized for antimicrobial activity, water vapor permeability (WVP), tensile strength (TS), percent elongation at break (%E), and water solubility (WS). Fourier transform infrared (FTIR) spectroscopy was conducted to determine functional group interactions between the matrix and lemongrass oil. The zone of inhibition was increased significantly (P < 0.05) by addition of lemongrass oil at all levels in the presence and the absence of glycerol. This indicates that the film containing lemongrass oil was effective against Escherichia coli O157:H7 at all levels. In the absence of glycerol, the tensile strength of film decreased as the oil content increased, but there was no significant (P > 0.05) difference in percent elongation. The percent elongation at break and WVP values for film with 20% glycerol was found to be increased significantly (P < 0.05) with an increase in lemongrass oil content. Addition of lemongrass oil did not have any interaction with the functional groups of films as measured by FTIR.
    Matched MeSH terms: Escherichia coli O157/drug effects*; Escherichia coli O157/growth & development
  4. Bacterial membrane disruption in food pathogens by Psidium guajava leaf extracts
    Henie, E.F.P., Zaiton, H., Suhaila, M.
    International Food Research Journal, 2009;16(3):297-311.
    MyJurnal
    The mode of action and activities of guava leaf extracts against various food pathogens were studied. The killing kinetics, viability and cell leakage of Kocuria rhizophila, Salmonella typhimurium, Listeria monocytogenes and Escherichia coli O157:H7, measured after exposure to guava methanolic extracts (GME) revealed a significantly higher (p≤0.05) release of bacterial nucleic acids, K+ ions and protein than that of untreated microbes, indicating disruption of the bacterial membrane. GME caused a significantly higher (p≤0.05) release of RNA in gramnegatives compared to gram-positives. GME caused a relatively small but significant release of pyrines and pyrimidines in all organisms investigated. GME probably disrupted the integrity of the Gram-negative microorganism lipopolysaccharide (LPS) layer. Unlike all the other microorganisms tested, E. coli O157:H7, demonstrated the lowest protein leakage, the highest K+ leakage, the highest pyrines and pyrimidines leakage within the first 10 min of extract exposure, but the lowest after 30 minutes, which may indicate their good homeostasis ability or adaptability. Understanding the mode of action of this flavonoid rich guava leaf extract, would help develop it as an alternative biodegradable and safe, antimicrobial for food and medicine, and as a by-product of the guava industry.
    Matched MeSH terms: Escherichia coli O157
  5. Fulltext Characteristics of childhood diarrhea associated with enterotoxigenic Escherichia coli in Malaysia
    Samuel S, Vadivelu J, Parasakthi N
    Southeast Asian J. Trop. Med. Public Health, 1997 Mar;28(1):114-9.
    PMID: 9322293
    Amongst 107 diarrheal cases studied a bacterial agent was isolated from 71 (66%) cases of which 60 (85%) were due to a single agent and the remaining 11 (15%) were of mixed infections. Enterotoxigenic Escherichia coli (ETEC) was isolated from 65 cases. Other pathogens isolated included Salmonella spp, Shigella spp and rotavirus. There was a higher isolation rate of ETEC from females and rotavirus from males. The infection rate was found to higher for the 0-2 year age group as compared to the 3-5 year age group. Amongst the ETEC isolated the STa 2 toxotype was the predominant type.
    Matched MeSH terms: Escherichia coli O157*
  6. Detection of Escherichia coli O157:H7 by multiplex PCR and their characterization by plasmid profiling, antimicrobial resistance, RAPD and PFGE analyses
    Radu S, Ling OW, Rusul G, Karim MI, Nishibuchi M
    J Microbiol Methods, 2001 Aug;46(2):131-9.
    PMID: 11412923
    Twenty-five and three strains of Escherichia coli O157:H7 were identified from 25 tenderloin beef and three chicken meat burger samples, respectively. The bacteria were recovered using the immunomagnetic separation procedure followed by selective plating on sorbitol MacConkey agar and were identified as E. coli serotype O157:H7 with three primer pairs that amplified fragments of the SLT-I, SLT-II and H7 genes in PCR assays. Susceptibility testing to 14 antibiotics showed that all were resistant to two or more antibiotics tested. Although all 28 strains contained plasmid, there was very little variation in the plasmid sizes observed. The most common plasmid of 60 MDa was detected in all strains. We used DNA fingerprinting by randomly amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) to compare the 28 E. coli O157:H7 strains. At a similarity level of 90%, the results of PFGE after restriction with XbaI separated the E. coli O157:H7 strains into 28 single isolates, whereas RAPD using a single 10-mer oligonucleotides separated the E. coli O157:H7 strains into two clusters and 22 single isolates. These typing methods should aid in the epidemiological clarification of the E. coli O157:H7 in the study area.
    Matched MeSH terms: Escherichia coli O157/classification*; Escherichia coli O157/isolation & purification*
  7. Detection of Escherichia coli O157:H7 in the beef marketed in Malaysia
    Radu S, Abdul Mutalib S, Rusul G, Ahmad Z, Morigaki T, Asai N, et al.
    Appl Environ Microbiol, 1998 Mar;64(3):1153-6.
    PMID: 9501454
    Twelve strains of Escherichia coli O157:H7 were isolated from 9 of 25 beef samples purchased from retail stores in Malaysia. These strains produced Shiga toxin 2 with or without Shiga toxin 1 and had the eae gene and a 60-MDa plasmid. The antibiograms and the profiles of the arbitrarily primed PCR of the strains were diverse, suggesting that the strains may have originated from diverse sources.
    Matched MeSH terms: Escherichia coli O157/isolation & purification*; Escherichia coli O157/pathogenicity
  8. Fulltext Effect of lipase hydrolysis on the antibacterial activity of coconut oil, palm mesocarp oil and selected seed oils against several pathogenic bacteria
    Lee, S.T., Ariffin, A., Son R., Ghazali, H.M.
    International Food Research Journal, 2015;22(1):46-54.
    MyJurnal
    The antibacterial activity of solvent-extracted oil of noni (Morinda citrifolia L.), spinach (Spinacia oleracea L.), lady’s finger (Abelmoschus esculentus (L.) Moench), bitter gourd (Momordica charantia Linn.), and mustard (Brassica nigra L.) seed oils, and coconut (Cocos nucifera L.) oil, palm (Elaeis guineensis L.) mesocarp in hydrolyzed and unhydrolyzed form were determined in order to explore their potential usage as antibacterial agent. The hydrolysis process that was catalyzed by immobilized lipase of Rhizomucor miehei (RMIM) showed highest hydrolytic activity with 1.0 ml of added water volume except bitter gourd seed oil and palm mesocarp oil which has maximum hydrolytic activity with added water volume of 5 ml and 2.5 ml respectively. Before hydrolysis, all oil samples did not show inhibition ring zones (IRZ) on any of the tested bacteria strains (Salmonella typhimurium, Listeria monocytogenes and Escherichia coli O157:H7). Hydrolyzed lady’s finger and bitter gourd seed oil showed IRZ on all tested bacteria strains; hydrolyzed mustard seed oil on S. typhimurium and L. monocytogenes; hydrolyzed spinach seed oil and coconut oil on L. monocytogenes; hydrolyzed noni seed oil and palm mesocarp oil did not exhibit IRZ on any of the tested bacteria strains. Most of the hydrolyzed oil exhibit an inhibition activity that was different from their respective dominant fatty acids except noni seed oil and palm mesocarp oil.
    Matched MeSH terms: Escherichia coli O157
  9. Effect of pore size and morphology of activated charcoal prepared from midribs of Elaeis guineensis on adsorption of poisons using metronidazole and Escherichia coli O157:H7 as a case study
    Ilomuanya MO, Nashiru B, Ifudu ND, Igwilo CI
    J Microsc Ultrastruct, 2016 05 12;5(1):32-38.
    PMID: 30023235 DOI: 10.1016/j.jmau.2016.05.001
    Agricultural waste obtained from Elaeis guineensis mid ribs can provide a veritable source of materials which can be used as precursor materials for the production of pharmaceutical grade activated charcoal. The pore size and surface morphology of activated charcoal defines the types of molecules that could be adsorbed unto it, as surface morphology plays a significant role in determining the surface availability and areas of adsorption. The activated charcoal samples prepared from Elaeis guineensis via either physical or chemical activation was characterized via surface area using the BET method and subsequently pore structure and size analyzed by scanning electron microscopy (SEM). Physically activated Elaeis guineensis fronds activated with nitrogen gas had wide spread microporosity with micropore volume of 0.232 cc/g compared to the chemically activated with 1M and 3M phosphoric acid respectively. The commercial activated charcoal/metronidazole combination in the in vitro-pharmacodynamic model reflected no re-growth after 4 hours, however for charcoal formulated from Elaeis guineensis via chemical activation with 3M phosphoric acid and metronidazole no regrowth was seen at the second hour and this was maintained throughout the duration of the experiment. Increased macroporosity enhanced bacterial adsorption and this was further facilitated by the presence of antibacterial metronidazole in the in vitro pharmacodynamic model. Activated charcoal produced from agricultural waste obtained from Elaeis guineensis dried mid ribs consisting of increased macroporosity with mixed meso/micro porosity and antibacterial metronidazole form the best model for bacterial adsorption and will be useful in the treatment of diarrhea caused by E. coli O157:H7.
    Matched MeSH terms: Escherichia coli O157
  10. Fulltext Effects of thermosonication on the fate of Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice
    Kiang WS, Bhat R, Rosma A, Cheng LH
    Lett Appl Microbiol, 2013 Apr;56(4):251-7.
    PMID: 23278854 DOI: 10.1111/lam.12042
    In this study, the effects of thermosonication and thermal treatment on Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice were investigated at 50 and 60°C. Besides, nonlethal injury of Salm. Enteritidis after both treatments was also examined. The highest inactivation was attained with thermosonication at 60°C. The inactivation rate was different for both pathogens, and Salm. Enteritidis was found to be more sensitive to thermosonication than E. coli O157:H7. Salmonella Enteritidis was recovered in all treated samples, except those subjected to more than 5-min thermosonication at 60°C. It was found that the introduction of high-intensity ultrasound enhanced the inactivation of pathogens compared to thermal treatment alone. On the other hand, Salm. Enteritidis was detected in a number of samples following incubation in universal pre-enrichment broth, but no growth was detected after incubation in mango juice.
    Matched MeSH terms: Escherichia coli O157/physiology*
  11. Escherichia coli strains expressing H12 antigens demonstrate an increased ability to attach to abiotic surfaces as compared with E. coli strains expressing H7 antigens
    Goulter RM, Taran E, Gentle IR, Gobius KS, Dykes GA
    Colloids Surf B Biointerfaces, 2014 Jul 1;119:90-8.
    PMID: 24880987 DOI: 10.1016/j.colsurfb.2014.04.003
    The role of Escherichia coli H antigens in hydrophobicity and attachment to glass, Teflon and stainless steel (SS) surfaces was investigated through construction of fliC knockout mutants in E. coli O157:H7, O1:H7 and O157:H12. Loss of FliC(H12) in E. coli O157:H12 decreased attachment to glass, Teflon and stainless steel surfaces (p<0.05). Complementing E. coli O157:H12 ΔfliC(H12) with cloned wildtype (wt) fliC(H12) restored attachment to wt levels. The loss of FliCH7 in E. coli O157:H7 and O1:H7 did not always alter attachment (p>0.05), but complementation with cloned fliC(H12), as opposed to cloned fliCH7, significantly increased attachment for both strains compared with wt counterparts (p<0.05). Hydrophobicity determined using bacterial adherence to hydrocarbons and contact angle measurements differed with fliC expression but was not correlated to the attachment to materials included in this study. Purified FliC was used to functionalise silicone nitride atomic force microscopy probes, which were used to measure adhesion forces between FliC and substrates. Although no significant difference in adhesion force was observed between FliC(H12) and FliCH7 probes, differences in force curves suggest different mechanism of attachment for FliC(H12) compared with FliCH7. These results indicate that E. coli strains expressing flagellar H12 antigens have an increased ability to attach to certain abiotic surfaces compared with E. coli strains expressing H7 antigens.
    Matched MeSH terms: Escherichia coli O157/genetics; Escherichia coli O157/metabolism; Escherichia coli O157/chemistry*
  12. Fingerprints of resistant Escherichia coli O157:H7 from vegetables and environmental samples
    Abakpa GO, Umoh VJ, Kamaruzaman S, Ibekwe M
    J Sci Food Agric, 2018 Jan;98(1):80-86.
    PMID: 28543177 DOI: 10.1002/jsfa.8441
    BACKGROUND: Some routes of transmission of Escherichia coli O157:H7 to fresh produce include contaminated irrigation water and manure polluted soils. The aim of the present study was to determine the genetic relationships of E. coli O157:H7 isolated from some produce growing region in Nigeria using enterobacterial repetitive intergenic consensus (ERIC) DNA fingerprinting analysis. A total of 440 samples comprising leafy greens, irrigation water, manure and soil were obtained from vegetable producing regions in Kano and Plateau States, Nigeria. Genes coding for the quinolone resistance-determinant (gyrA) and plasmid (pCT) coding for multidrug resistance (MDR) were determined using polymerase chain reaction (PCR) in 16 isolates that showed MDR.

    RESULTS: Cluster analysis of the ERIC-PCR profiles based on band sizes revealed six main clusters from the sixteen isolates analysed. The largest cluster (cluster 3) grouped isolates from vegetables and manure at a similarity coefficient of 0.72.

    CONCLUSION: The present study provides data that support the potential transmission of resistant strains of E. coli O157:H7 from vegetables and environmental sources to humans with potential public health implications, especially in developing countries. © 2017 Society of Chemical Industry.

    Matched MeSH terms: Escherichia coli O157/classification; Escherichia coli O157/drug effects; Escherichia coli O157/genetics; Escherichia coli O157/isolation & purification*
  13. Genetic characterization of Escherichia coli O157: H7/- strains carrying the stx2 gene but not producing Shiga toxin 2
    Koitabashi T, Vuddhakul V, Radu S, Morigaki T, Asai N, Nakaguchi Y, et al.
    Microbiol. Immunol., 2006;50(2):135-48.
    PMID: 16490932
    Nine Escherichia coli O157: H7/- strains isolated primarily from non-clinical sources in Thailand and Japan carried the stx(2) gene but did not produce Stx2 toxin in a reversed passive latex agglutination (RPLA) assay. A strain (EDL933) bearing a stx(2) phage (933W) was compared to a strain (Thai-12) that was Stx2-negative but contained the stx(2) gene. To study the lack of Stx2 production, the Thai-12 stx(2) gene and its upstream nucleotide sequence were analyzed. The Thai-12 stx(2) coding region was intact and Stx2 was expressed from a cloned stx(2) gene using a plasmid vector and detected using RPLA. A lacZ fusion analysis found the Thai-12 stx(2) promoter non-functional. Because the stx(2) gene is downstream of the late promoter in the stx(2) phage genome, the antitermination activity of Q protein is essential for strong stx(2) transcription. Thai-12 had the q gene highly homologous to that of Phi21 phage but not to the 933W phage. High-level expression of exogenous q genes demonstrated Q antitermination activity was weak in Thai-12. Replication of stx(2) phage was not observed in Stx2-negative strains. The q-stx(2) gene sequence of Thai-12 was well conserved in all Stx2-negative strains. A PCR assay to detect the Thai-12 q-stx(2) sequence demonstrated that 30% of O157 strains from marketed Malaysian beef carried this sequence and they produced little or no Stx2. These results suggest that stx(2)-positive O157 strains that produce little or no Stx2 may be widely distributed in the Asian environment.
    Matched MeSH terms: Escherichia coli O157/genetics*; Escherichia coli O157/metabolism*
  14. Highly sensitive Escherichia coli shear horizontal surface acoustic wave biosensor with silicon dioxide nanostructures
    Ten ST, Hashim U, Gopinath SC, Liu WW, Foo KL, Sam ST, et al.
    Biosens Bioelectron, 2017 Jul 15;93:146-154.
    PMID: 27660016 DOI: 10.1016/j.bios.2016.09.035
    Surface acoustic wave mediated transductions have been widely used in the sensors and actuators applications. In this study, a shear horizontal surface acoustic wave (SHSAW) was used for the detection of food pathogenic Escherichia coli O157:H7 (E.coli O157:H7), a dangerous strain among 225 E. coli unique serotypes. A few cells of this bacterium are able to cause young children to be most vulnerable to serious complications. Presence of higher than 1cfu E.coli O157:H7 in 25g of food has been considered as a dangerous level. The SHSAW biosensor was fabricated on 64° YX LiNbO3 substrate. Its sensitivity was enhanced by depositing 130.5nm thin layer of SiO2 nanostructures with particle size lesser than 70nm. The nanostructures act both as a waveguide as well as a physical surface modification of the sensor prior to biomolecular immobilization. A specific DNA sequence from E. coli O157:H7 having 22 mers as an amine-terminated probe ssDNA was immobilized on the thin film sensing area through chemical functionalization [(CHO-(CH2)3-CHO) and APTES; NH2-(CH2)3-Si(OC2H5)3]. The high-performance of sensor was shown with the specific oligonucleotide target and attained the sensitivity of 0.6439nM/0.1kHz and detection limit was down to 1.8femto-molar (1.8×10(-15)M). Further evidence was provided by specificity analysis using single mismatched and complementary oligonucleotide sequences.
    Matched MeSH terms: Escherichia coli O157/isolation & purification*; Escherichia coli O157/pathogenicity
  15. Immune-stimulating properties of 80% methanolic extract of Ludwigia octovalvis against Shiga toxin-producing E. coli O157:H7 in Balb/c mice following experimental infection
    Kadum Yakob H, Manaf Uyub A, Fariza Sulaiman S
    J Ethnopharmacol, 2015 Aug 22;172:30-7.
    PMID: 26091966 DOI: 10.1016/j.jep.2015.06.006
    Ludwigia octovalvis is an aquatic plant widely distributed throughout the tropical and sub-tropical regions. It is commonly consumed as a health drink and traditionally used for treating various ailments such as dysentery, diarrhea, diabetes, nephritisn and headache. No information is available on its in vivo antibacterial activity against an important foodborne pathogen, Shiga toxin producing Escherichia coli O157:H7.
    Matched MeSH terms: Escherichia coli O157/drug effects*; Escherichia coli O157/immunology; Escherichia coli O157/metabolism
  16. Incidence of escherichia coli O157:H7 in Thailand
    Pharanai Sukhumungoon
    Sains Malaysiana, 2015;44:261-267.
    Enterohemorrhagic Escherichia coli (EHEC) especially serotype O157:H7 is one of the important food-borne pathogens because it is able to produce crucial toxins Shiga. However, the outbreak of this organism in Thailand has not been reported. Antibody to O157 antigen was detected in some Thai populations and Shiga toxin-producing E. coli were detected in low numbers of clinical specimens. Interestingly, some E. coli that showed positive to O157 fimbriae probe and lack of virulence gene were isolated from certain patients and one isolate of E. coli O157:H7 which possessed stx1, stx2v was detected in a normal child. In addition, the incidence of E. coli O157:H7 strains were monitored by the samples from cattle and retail beef in Thailand although their inability to produce toxins or produce in a low concentration was demonstrated. This review discusses the incidences of E. coli O157 in clinical and environmental samples of Thailand including the transmission possibility of this bacterium across the Thai border through food trade.
    Matched MeSH terms: Escherichia coli O157
  17. Investigating to some microbial pollution parameters of seawater and mussels (mytilus galloprovincialis, Lamarck 1819) of Sіnop Black Sea Coastal Zone, Turkey
    Ismet Berber, Cumhur Avsar
    Sains Malaysiana, 2014;43:1835-1842.
    The presence of coliforms bacteria is one of the most prevalent problems in terms of public health in marine ecosystems over the world. In this study were investigated the physico-chemical properties of seawater and the numbers of total aerobic, total coliform, fecal coliform, E. coli O157:H7 and fecal streptococci in seawater and mussel samples collected from Sinop environs between May and October 2011. The microbiological analysis of seawater samples showed that the difference between total coliform, fecal coliform and fecal streptococci numbers (p<0.05) was significant for each station. However, the difference among total aerobic bacteria numbers for each stations (p>0.05) were not found significant. The difference between whole counting results for mussel samples taken from different sampling sites was not significant (p>0.05), too. Furthermore, the results of the screening assay for the presence of E. coli O157:H7 showed that the strain was not detected in neither seawater nor mussel samples. In conclusion, it was determined that fecal coliform and fecal streptococci counts in the seawater and mussel samples were higher than legal (Turkish Bathing Water and Quality of Fishery Products Regulation) limit values for some stations in Sinop coastal areas.
    Matched MeSH terms: Escherichia coli O157
  18. Fulltext Investigation of stx 2 + eae + Escherichia coli O157:H7 in beef imported from Malaysia to Thailand
    International Food Research Journal, 2011;18(1):381-386.
    MyJurnal
    To gain insight into the microbiological safety of food products routinely traded across international borders in Southeast Asian countries, beef imported from Malaysia to southern Thailand was examined for contamination with Escherichia coli O157 and its subsequent spread into the imported areas. We screened 31 samples exported from Malaysia and 36 domestic Thai samples. Isolation methods including an O157 antigen-targeted immunomagnetic separation technique, screening on CHROMagar O157 medium, and serotype confirmation of E. coli isolates by specific agglutination tests were employed. Fourteen strains of E. coli O157:H7 were isolated from eight Malaysian samples (25.8%) and six strains from four Thai samples (11.1%). These strains were of the stx1-stx2+eae+ genotype except one Malaysian strain which was of the stx1- stx2- eae+ genotype. All 19 O157:H7 strains possessing the stx2 gene produced little or no Stx2 (reversed passive latex agglutination titer ≤ 4). Of the 19 strains, five Malaysian (38.5%) and two Thai (33.3%) strains exhibited resistance to a set of antibiotics. Finally, the results of two DNA fingerprinting
    analyses (O157 IS-printing targeted to IS629 and pulsed-field gel electrophoresis, PFGE) of the O157:H7 strains possessing the stx2 gene, indicated that the Malaysian and Thai strains are closely related. Therefore, E. coli O157:H7 might be transferred from Malaysia to southern Thailand through beef trade.
    Matched MeSH terms: Escherichia coli O157
  19. Isolation of an Escherichia coli O157:H7 strain producing Shiga toxin 1 but not Shiga toxin 2 from a patient with hemolytic uremic syndrome in Korea
    Kim YB, Okuda J, Matsumoto C, Morigaki T, Asai N, Watanabe H, et al.
    FEMS Microbiol Lett, 1998 Sep 01;166(1):43-8.
    PMID: 9741083
    Escherichia coli strains isolated from patients with diarrhea or hemolytic uremic syndrome (HUS) at Pusan University Hospital, South Korea, between 1990 and 1996 were examined for traits of the O157:H7 serogroup. One strain isolated from a patient with HUS belonged to the O157:H7 serotype, possessed a 60-MDa plasmid, the eae gene, and ability to produce Shiga toxin 1 but not Shiga toxin 2. Arbitrarily primed PCR analysis suggested that this strain is genetically very close to a O157:H7 strain isolated in Japan.
    Matched MeSH terms: Escherichia coli O157/genetics; Escherichia coli O157/isolation & purification*; Escherichia coli O157/metabolism*
  20. Lactic acid as a potential decontaminant of selected foodborne pathogenic bacteria in shrimp (Penaeus merguiensis de Man)
    Shirazinejad A, Ismail N, Bhat R
    Foodborne Pathog Dis, 2010 Dec;7(12):1531-6.
    PMID: 21034165 DOI: 10.1089/fpd.2010.0616
    Fresh raw shrimps were dipped for 10, 20, and 30 min at room temperature (25°C ± 1°C) in lactic acid (LA; 1.5%, 3.0%, v/v) to evaluate their antipathogenic effects against Vibrio cholerae, Vibrio parahaemolyticus, Salmonella entreitidis, and Escherichia coli O157:H7 inoculated at a level of 10(5) CFU/g. Significant reductions in the population of all these pathogenic bacteria were recorded after dipping treatments, which were correlated to the corresponding LA concentrations and treatment time. With respect to the microbial quality, 3.0% LA treatment for 10 min was acceptable in reducing the pathogenic bacteria. Additionally, sensory evaluation results revealed a 10-min dip in 3.0% LA to be more acceptable organoleptically compared with 20 and 30 min of treatments. Results of the present study are envisaged to be useful for commercial applications for effective decontamination of shrimp.
    Matched MeSH terms: Escherichia coli O157/drug effects
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links