• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1731-1739
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• 2012

In this study, seven strains isolated from mustard leaf kimchi were screened for their tolerance to simulated gastric and bile juices, the adhesive properties to Caco-2 cells, and the inhibition ability of Salmonella Typhimurium ATCC 29631 adhesion. Lactobacillus acidophilus GK20, Lactobacillus paracasei GK74, and Lactobacillus plantarum GK81, which were resistant to bile as well as gastric juices, possessed high bile-salt hydrolase (BSH) activity towards both sodium glycocholate and sodium taurocholate. The strongest in vitro adherence of $53.96{\pm}4.49%$ was exhibited by L. plantarum GK81 followed by L. acidophilus GK20 with adhesion levels of $40.72{\pm}9.46%$. The adhesion of these strains was significantly (p < 0.05) reduced after exposure to pepsin and heating for 30 min at $80^{\circ}C$. Addition of $Ca^{2+}$ led to a significant (p < 0.05) increase of the adhesion of L. acidophilus GK20, but the adhesion ability of L. plantarum GK81 was not different from the control by the addition of calcium. In the competition and exclusion experiment, the adhesion inhibition of S. Typhimurium by L. plantarum GK81 strain was much higher than the other strains. Moreover, the exclusion inhibition of S. Typhimurium by L. acidophilus GK20 was considerably high, although the inhibition activity of this strain was lower than L. plantarum GK81.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.189-194
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• 2020

In this study, we investigated the efficacy of Salmonella phage P22 combined with antibiotics to inhibit antibiotic-resistant S. Typhimurium CCARM 8009. The synergistic effect of phage P22 and antibiotics was evaluated by using disk diffusion and broth dilution assays. The development of Antimicrobial resistance was determined after time-kill assay. The antibiotic susceptibility assay showed the inhibition zone sizes around the antibiotic disks were increased up to 78.8% in the presence of phage (cefotaxime; 13.6%, chloramphenicol; 19.3%, ciprofloxacin; 12.7% and erythromycin; 78.8%). The minimum inhibitory concentration values of the combination treatment significantly decreased from 256 to 64 mg/mL for tetracycline, 8 to 4 mg/mL for chloramphenicol, 0.0156 to 0.0078 mg/mL for ciprofloxacin, 128 to 64 mg/mL for erythromycin and 512 to 256 mg/mL for streptomycin. The number of S. Typhimurium CCARM 8009 was approximately 4-log lower than that of the control throughout the combination treatment with phage P22 and ciprofloxacin delete at 37℃ for 20 h. The results indicate that the development of antimicrobial resistance in S. Typhimurium could be reduced in the presence of phage treatment. This study provides promising evidence for the phage-antibiotic combination as an effective treatment to control antibiotic-resistant bacteria.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.2
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• pp.207-213
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• 1999

This study was carried out to get a industrial information about a possibility of IgY antibody production, antimicrobial activity and properties of IgY antibody in egg yolk. The residual antibody activities of IgY were 91.5% after heating for 30min at 6$0^{\circ}C$. At the same time. these activities, were 73.2% after heating 15min at $65^{\circ}C$ and decreased vapidly at 7$0^{\circ}C$ and little antibody activity was left after heating for 15min at 8$0^{\circ}C$. When the prepared IgY was incubated at various pH ranges from 7 to 2 for 5hr at 37$^{\circ}C$., the antibody activity was stable from pH 7 to 4 and remained to 69.8% at pH 3.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.234-240
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• 2013

This test was performed to evaluate the bactericidal efficacy of Fumagari OPP$^{(R)}$, fumigation disinfectant, containing 20% ortho-phenylphenol against Escherichia coli (E. coli) and Salmonella typhimurium (S. typhimurium). In preliminary tests, both E. coli and S. typhimurium working culture suspension number (N value) was $4.0{\times}10^8$ CFU/mL. And all of the colony numbers on the carriers exposed the fumigant (n1, n2, n3) were higher than 0.5N1 (the number of bacterial test suspentions by pour plate method), 0.5N2 (the number of bacterial test suspentions by filter membrane method) and 0.5N1, respectively. In addition, the mean number of bacteria recovered on the control-carriers (T value) was $3.4{\times}10^6$ CFU/mL. In the bactericidal effect of the fumigant, the reduction number of S. typhimurium and E. coli (d value) was 5.26 and 5.64 logCFU/mL, respectively. According to the French standard for the fumigant, the d value for the effective bactericidal fumigant should be over than 5 logCFU/mL. With the results of this study, Fumagari OPP$^{(R)}$ has an effective bactericidal activity, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with pathogenic bacteria.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.419-425
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• 1999

Prophylactic effects of Bifidobacterium longum HY8001, Korean isolate, against Escherichia coli O157:H7 and Salmonella typhimurium DT104 enteric infection were examined at four groups of specific pathogen free(SPF)-ICR mouse for each pathogen. B. longum HY8001+B. typhimurium DT104+B. longum HY8001(BL+ST+BL) group and B. longum HY8001+E. coli O157:H7+B. longum HY8001(BL+E+BL) group were fed with B. longum HY8001 before and after E. coli O157:H7 or s. typhimurium DT104 challenge, while B. longum HY8001+S. typhimurium DT104(BL+ST) and B. longum HY8001+e. coli O157:H7(BL+E) groups were fed with B. longum HY8001 only before E. coli O157:H7 or S. typhimurium DT104 challenge. E. coli O157:H7(E) and S. typhimurium DT104(ST) groups were challenged with each pathogen without B. longum HY8001 administration and control groups were administered with phosphate buffered solution(PBS). After the oral administration with B. longum HY8001(109cfu), th emice were challenged with E. coli O157:H7(2$\times$1010cfu) or S. typhimurium DT104(108cfu) and the mortality rate and the fecal shedding of challenged pathogen were also examined define the reactivity of the B. longum HY8001. Production of toxin neutralizing substance(s) of B. longum HY8001 was determined by cell cytotoxicity assay using Vero cells. Fecal shedding of th eS. typhimurium DT104 was significantly decreased in BL+ST+BL group fed with B. longum HY8--1 before and after challenge(p<0.05), while the fecal shedding s of S. typhimurium DT104 in BL+ST and St groups remained more than 106cfu. the protective effect of the B. longum HY8001 against E. coli O157:H7 was significantly high only in BL+E+BL group fed with b. longum Hy8001 before and after E. coli O157:H7 challenge from the result of fecal E. coli O157:H7 isolation rate, mortality rate, and intestinal contents culture to detect E. coli O157:H7. the mortality rate of the BL+e and E groups. The cytopathic effect (CPE) of the Vero cytotoxin (Shiga like toxin I & II) in Vero cell was neutralized in B. longum HY8001 culture supernatant added wells which indicate the presence of soluble Vero cytotxin neutralizing substance(s) in B. longum HY8001 culture suprnatant.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.495-499
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• 2018

The reduction effect of UV-C irradiation and mild heat treatment was examined against Escherichia coli O157:H7 and Salmonella Typhimurium on black pepper powder. E. coli O157:H7 (ATCC 35150) and S. Typhimurium (ATCC 19585) were inoculated onto black pepper powder at approximately $10^7$ and $10^6CFU/g$, respectively. E. coli O157:H7 and S. Typhimurium were treated with UV-C and mild heat at $60^{\circ}C$. A UV-C intensity ($2.32W/cm^2$ ) was used for 10 min to 70 min at $60^{\circ}C$. After UV-C and heat treatment at $60^{\circ}C$, microbial analysis and color change of black pepper powder was conducted. E. coli O157:H7 and S. Typhimurium were reduced by a level of 1.89 and 2.24 log CFU/g, respectively, when treated with UV-C alone for 70 min. And E. coli O157:H7 and S. Typhimurium were reduced by 2.22 and 5.10 log CFU/g, respectively, when treated with mild heat treatment at $60^{\circ}C$ alone for 70 min. But when combined with UV-C and mild heat, it showed higher levels of reduction by 2.46 and 5.70 log CFU/g. S. Typhimurium was more easily reduced than E. coli O157:H7. Color values were not significantly (p > 0.05) different in all treated samples. Therefore, these results suggest that the combined treatment with UV-C and mild heat was effective to inactivate the food pathogens in black pepper powder and can be used as a food industrial microbial intervention method.

• Biomolecules & Therapeutics
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• v.6 no.1
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• pp.63-72
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• 1998

-4-Quinolone antibiotics (pefloxacin, ciprofloxacin, norfoxacin, ofloxacin and enoxacin) were tested for mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, TA1537, TA1538 and TA102, for chromosomal aberrations in cultured Chinese hamster lung (CHL) cells, and for wing somatic mutations and recombinations (wing spot) in Drosophila. Five 4-quinolones did not show any mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, TA1537 and TA1538. However, they were mutagenic inSalmonella typhimurium TA102 with and without metabolic activation in both plate incorporation method and preincubation method. Ciprofloxacin induced structural chromosome aberrations in CHL cells both with and without metabolic activation, and the frequencies were 6% and up to 28%, respectively. Pefloxacin showed equivocal evidence, however, norfloxacin, ofloxacin and enoxacin did not induce the structural chromosome aberrations both in the presence and absence of metabolic activation. In the wing spot assay in Drosophila, ofloxacin increased the frequency of small single spots significantly in a dose-dependent manner but there was no dose-dependent increase of single or twin spots in the others.

• Korean Journal of Veterinary Research
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• v.53 no.3
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• pp.163-167
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• 2013

Avian pathogenic Escherichia coli (APEC) are known to cause extraintestinal disease in poultry, leading to substantial losses in the industry. IutA, iron-regulated aerobactin receptor is firmly associated with APEC. To assess the potential of IutA to induce protective immune responses, attenuated Salmonella Typhimurium strain expressing IutA was constructed and administered orally to BALB/c mice. The IutA-specific immune responses were measured with sera, vaginal and fecal samples by an enzyme-linked immunosorbent assay. We found that the Salmonella-IutA vaccine induced significantly higher immune responses as compared to the control inoculated with the attenuated S. Typhimurium containing the plasmid only. The IutA-specific immune responses were increased by second immunization at third week after initial immunization, whereas triple immunization induced lower immune responses than those induced by the double immunization. The Salmonella-IutA vaccine induced a nature of immunity biased to the Th1-type, as judged by the ratio of IutA-specific IgG isotypes (IgG2a/IgG1). Overall, these results suggest that the Salmonella-IutA vaccine appear to be suitable candidate for a vaccine against APEC.

• Journal of Life Science
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• v.8 no.2
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• pp.216-225
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• 1998

Metal ion-induced and it’s regulatory genes were screened in virulent salmonella typhimurium UK1 and tested cross-regulation with various stresses. Using the techniqud of P22-MudJ(Km, lacZ)-directed lacZ operon fusion, LF40 cuiA::MudJ and Lf153 cuiD::MudJ which were induced by copper were selected. cuia and cuiD were determined anaerobic coper inducible and copper tolerance response gene, respectively. Also cuiA and cuiD locus were determined at 81 and 8min, respectively, on salmonella Genetic Map. The two regulators were identified as cuaR, and cudR, which controls cuiA and cuiD, respectively. cuaR, and cudR appeared as negative regulators because the expression of cuiA-lac-Z and cuiD-lacZ were increased. Copper adapted UK1 showed high resistance to H$_{2}$O$_{2}$, but cuiD did not. The product of the cudR locus was responsible for decreasing the tolerance to copper and H$_{2}$O$_{2}$. Furthemore cuiA and cuiD locus were found to be part of a regulon under the control of a trans-acting regulators, rpoS, oxyR and relA. Therefore, the results suggest CTR participate with oxidative stress on Salmonella.

• KSBB Journal
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• v.11 no.4
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• pp.420-430
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• 1996

One-step immuno-chromatography assay system for heat-killed Salmonella typhimurium antigens was developed. Three major components used were a glass fiber membrane (placed at the bottom of the system) with an antibody (specific to the analyse, detection antibody)-gold conjugate deposited in a dry state on the surface, a nitrocellulose membrane (middle) with an antibody (also, specific to the analyse but recognized different epitome: capture antibody) and anti-detection antibody immobilized in spatially separated areas, and a cellulose membrane (top) as absorption pad. These membranes were partially superimposed such that a wicking of aqueous solution containing sample can continuously take place through membranes. Variables that affected the system performance were the concentration of capture antibody, the location on the membrane, inert protein used for blocking of the membrane and for carrying the sample, and the concentration of the gold conjugate. Under optimal conditions, within 15 minutes after absorption of a sample solution from the bottom of the system antigen-antibody complexes of sandwich type were formed on the membrane surface area with immobilized capture antibody and a color signal was generated in proportion to the analyse concentration. The minimum do tection limit of the analyse was $1{\times}106$ Salmonella cells/mL.