• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.878-884
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• 2013

Salmonella is a major foodborne pathogen that causes a variety of human diseases. Development of ligands directly and specifically binding to the Salmonella will be crucial for the rapid detection of, and thus for efficient protection from, the virulent bacteria. In this study, we identified a RNA aptamer-based ligand that can specifically recognize Salmonella Typhimurium through SELEX technology. To this end, we isolated and characterized an RNase-resistant RNA aptamer that bound to the OmpC protein of Salmonella Typhimurium with high specificity and affinity ($K_d$ ~ 20 nM). Of note, the selected aptamer was found to specifically bind to Salmonella Typhimurium, but neither to Gram-positive bacteria (Staphylococcus aureus) nor to other Gram-negative bacteria (Escherichia coli O157:H7). This was evinced by aptamer-immobilized ELISA and aptamer-linked precipitation experiments. This Salmonella species-specific aptamer could be useful as a diagnostic ligand against pathogen-caused foodborne sickness.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.97-103
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• 1999

This study was carried out to isolate and identify Salmonella species from poultry slaughterhouses and pork meat processing plants during the period from January 1997 to August 1998, and analyze resistance of antimicrobial agents and plasmid profiles of isolated Salmonella strains. A total of 15 Salmonella strains was isolated from poultry carcasses, swine carcasses, pork meats and cutting boards. Identified Salmonella strains were S. typhimurium, S. heidelberg, S. hilingdon, S. mbandaka, and S. virginia. Ten (66.7%) of 15 Salmonella strains showed resistance to antimicrobial agents and five strains (33.3%) of them were resistant to two or more antimirobial agents. Plasmids were isolated from three Salmonella isolates which had two or more plasmids.

• Korean Journal of Poultry Science
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• v.40 no.3
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• pp.277-281
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• 2013

The experiment was undertaken to see the effects of Bacillus sp. on the growth performance and disease resistance to Salmonella sp. infections. The use of probiotic microbes in poultry is commonly practiced. In this study, Bacillus subtilis was tested using a total of 120 chicks of age of 1 day after hatching. The growth traits examined were body weight gain and feed conversion rate. And also, the Salmonella resistance of Bacillus subtilis was tested after the chicks were orally administered with Salmonella pullorum by gavage force injections. The result showed that Bacillus subtilis yielded a high feed efficiency, consequently increased growth rate. For the effect of Bacillus subtilis on Salmonella infection, Bacillus subtilis significantly improved the resistance to Salmonella pullorum infection. Various clinical symptoms of Salmonella infection were highly decreased by addition of Bacillus sp.

• Korean Journal of Poultry Science
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• v.49 no.4
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• pp.281-286
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• 2022

This study was conducted to investigate the detection rate and serotypes of Salmonella spp. in conventional and welfare poultry farms. Ten welfare (five layer and five broiler) and 15 conventional farms (five layer and ten broiler farms) were visited to collect environmental samples for identification and serotyping of Salmonella spp. The detection rate of Salmonella spp. was higher in the welfare farms than in conventional farms in both layer and broiler farms. In layer farms, Salmonella spp. was detected in 0.76% (1 out of 130) of samples from one of five welfare layer farms, but was not detected in the five in conventional layer farms. No significan ifference (P>0.05) was observed between the welfare and conventional layer farms. In broiler farms, Salmonella spp. was detected in 10.5% (21 out of 200) of samples from four of five welfare broiler farms and 3.5% (7 out of 200) of samples from five of ten conventional broiler farms, and a significant difference (p <0.05) was observed between the welfare and conventional broiler farms. Among 29 Salmonella spp. isolates, five isolates were serotyped to Salmonella enterica subsp. Enteritidis (n=2), Salmonella enterica subsp. Grampian (n=1), Salmonella enterica subsp. Virchow (n=1), and Salmonella enterica subsp. Senftenberg (n=1). These results suggest that microbial risks could be higher in welfare farms than in conventional farms due to easy access to open-air areas, environmental enrichment, and reduced use of antibiotics. Therefore, continuous monitoring and surveillance for Salmonella spp. is necessary to improve the microbiological safety of poultry meat.

• Molecules and Cells
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• v.39 no.7
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• pp.566-572
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• 2016

Lysosomes are cellular organelles containing diverse classes of catabolic enzymes that are implicated in diverse cellular processes including phagocytosis, autophagy, lipid transport, and aging. Lysosome-associated membrane proteins (LAMP-1 and LAMP-2) are major glycoproteins important for maintaining lysosomal integrity, pH, and catabolism. LAMP-1 and LAMP-2 are constitutively expressed in Salmonella-infected cells and are recruited to Salmonella-containing vacuoles (SCVs) as well as Salmonella- induced filaments (Sifs) that promote the survival and proliferation of the Salmonella. LAMP-3, also known as DC-LAMP/CD208, is a member of the LAMP family of proteins, but its role during Salmonella infection remains unclear. DNA microarray analysis identified LAMP-3 as one of the genes responding to LPS stimulation in THP-1 macrophage cells. Subsequent analyses reveal that LPS and Salmonella induced the expression of LAMP-3 at both the transcriptional and translational levels. Confocal Super resolution N-SIM imaging revealed that LAMP-3, like LAMP-2, shifts its localization from the cell surface to alongside Salmonella. Knockdown of LAMP-3 by specific siRNAs decreased the number of Salmonella recovered from the infected cells. Therefore, we conclude that LAMP-3 is induced by Salmonella infection and recruited to the Salmonella pathogen for intracellular proliferation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.927-932
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• 1994

A total of 34 Salmonella sp. an d25 Shigella sp. were isolated from 311 patients with diarrhea. The isolation rates of Salmonella sp. ad Shigella sp. were 10.9% and 8%, respectively. The serogroups of 34 Salmonella sp. were in order of group D(50%), group B(38.25), group E(8.8%) and group C 92, 9%0. the serogroups of 25 Shigella sp. were group D(96%) and group B(4%). Seasonal distribution of isolated Salmonella sp. and Shigella sp. were shown the most high at July, 17.65% and 64%, respectively. Age group distribution of isolated Salmonella sp. and Shigella sp. were shown the most high at twenties and thirties (23.5%), and teens(76%), respectively. The Salmonella isolates were resistant in order of prevalence use of streptomycin(SM) (100%), erythromycin (EM) and movobiocin (NB)(90.6%), penicillin G(PG) (65.6%) and cephalexin (CPX)(46.9%). the isolates of Shigella sp. were resistant in order of prevalence use of EM (95.8%), NB(91.7%), SM(87.5%). Eighteen kinds of resistant patterns of Salmonella ioslates were detected. The multiple resistance patterns of Shigella isolates were mostly SM, EM, NB type (79.2%). The minimum inhibitory concentration of Salmonella sp. and Shigella sp. and Shigella sp. isolated from patients with diarrhea were tabulated.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.290-295
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• 2019

Salmonella spp. are frequently associated with food and are among the most important foodborne pathogens. The recent Salmonella out breaks in Korea was associated with chocolate mousse cakes served with school meals during September 2018. The objective of this research was to compare the 3M Molecular Detection Assay 2 - Salmonella and the Korean Standard Method of Salmonella in artificially inoculated mousse (chocolate and cheese) and tiramisu cakes. Mousse (chocolate and cheese) and tiramisu cakes were artificially inoculated with S. Typhimurium. Twenty five gram of sample was enriched with 225 mL buffered peptone water for incubation at $37^{\circ}C$ for 24 h. After enrichment, the cultures were analyzed by using the 3M Molecular Detection Assay 2 - Salmonella and the Korean Standard Method. Most of the inoculated samples showed similar results except the chocolate mousse cakes, in which real-time PCR was unable to detect S. Typhimurium even after $10^4CFU/25g$ of inoculation. However, S. Typhimurium inoculated at a concentration of $10^0CFU/25g$ was detected by using 3M Molecular Detection Assay 2 - Salmonella. In chocolate mousse, detection of S. Typhimurium using real-time PCR was partially successful when dark chocolate was added at less than 15%. Negative results in real-time PCR and 3M Molecular Detection Assay 2 - Salmonella were confirmed by gel electrophoresis. The data indicated that dark chocolate could inhibit amplification of the target gene in the PCR reactions. In conclusion, the 3M Molecular Detection Assay 2 - Salmonella was better than the Korean Standard Method (real-time PCR) for the detection of S. Typhimurium in chocolate mousse cakes and chocolate mousse.

• Toxicological Research
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• v.29 no.2
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• pp.129-135
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• 2013

Salmonella is one of the major pathogenic bacteria that cause food poisoning. This study investigated whether heat-killed as well as live Lactobacillus protects host animal against Salmonella infection. Live and heat-killed Lactobacillusacidophilus was administered orally to Sprague-Dawley rats for 2 weeks before the rats were inoculated with Salmonella. Rise in body temperature was moderate in the group that was treated with heat-killed bacteria as compared to the Salmonella control group. The mean amount of feed intake and water consumption of each rat in the heat-killed bacteria group were nearly normal. The number of fecal Salmonellae was comparable between the live and the heat-killed L. acidophilus groups. This finding shows that L. acidophilus facilitates the excretion of Salmonella. Moreover, the levels of pro inflammatory cytokines, including tumor necrosis factor (TNF)-alpha and interleukin (IL)-1 beta, in the heat-killed L. acidophilus group were significantly lower when compared to the levels in the Salmonella control group. These results indicate that nonviable lactic acid bacteria also could play an important role in preventing infections by enteric pathogens such as Salmonella.

• Korean Journal of Agricultural Science
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• v.41 no.1
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• pp.35-40
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• 2014

This study was carried out to evaluate the Salmonella cross contamination at retail chicken meat outlets in Kandy, Sri Lanka and to identify the risk factors for Salmonella contamination at retail chicken meat outlets. Fifteen retail chicken meat outlets in Kandy area were randomly selected. Pre-tested questionnaires were used to collect data for identifying risk factors of Salmonella cross contamination at retail outlets and swab samples from meat contact surfaces/utensils were obtained. Out of 57 swab samples collected from meat contact surfaces/utensils, the overall prevalence of Salmonella cross contamination was 21%. Weighing scale (33%), meat containing trays/buckets (27%) and cutting board (25%) showed the highest percentage of Salmonella prevalence whereas knife and showcase showed relatively low percentages, 14% and 9%, respectively. Retail chicken outlets with slaughtering facilities had a significantly higher prevalence of Salmonella cross contamination than those without slaughtering facilities. This higher rate of Salmonella cross contamination at retail chicken meat outlets could be attributed to lack of proper cold chains and minimal facilities, and poor level of hygiene in those outlets.

• Korean Journal of Veterinary Research
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• v.55 no.4
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• pp.241-246
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• 2015

To develop a live vaccine strain against fowl typhoid and paratyphoid caused by Salmonella serovar Gallinarum biovar Gallinarum (Salmonella Gallinarum) and Salmonella serovar Enteritidis (Salmonella Enteritidis), respectively, several nalidixic acid resistant mutants were selected from lipopolysaccharide (LPS) rough strains of Salmonella Gallinarum that escaped from fatal infection of a LPS-binding lytic bacteriophage. A non-virulent and immunogenic vaccine strain of Salmonella Gallinarum, SR2-N6, was established through in vivo pathogenicity and protection efficacy tests. SR2-N6 was highly protective against Salmonella Gallinarum and Salmonella Enteritidis and safer than Salmonella Gallinarum vaccine strain SG 9R in the condition of protein-energy malnutrition. Thus, SR2-N6 may be a safe and efficacious vaccine strain to prevent both fowl typhoid and paratyphoid.