• 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.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.176-181
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• 2004

The specificity of sandwich enzyme-linked immunosorbent assay (ELISA) to detect Salmonella in milk was determined in this study. The antibodies used in sandwich ELISA were egg yolk immunoglobulin G (IgY) obtained after immunization of hen with outer membrane protein (OMP) fraction from Salmonella typhimurium and rabbit IgG obtained after immunization of rabbit with the purified OMP with the molecular weight of 40,000. The immunoblot assay showed that the IgY reacted strongly with OMP with the molecular weight of 6,000 and the rabbit IgG reacted strongly with OMP with the molecular weights of 40,000, 35,000, and 6,000 from the bacteria including Salmonella which belongs to Enterobacteriaceae. The IgY and rabbit IgG also reacted with other proteins from Salmonella typhimurium in immunoblot assay. Competitive ELISA showed that IgY showed specifity to react with two strains of Salmonella typhimurium and Salmonella cholerasuis but not with Escherichia coli and Yersinia enterocolitica. Two strains of Salmonella typhimurium added to UHT milk showed the highest absorbance of all the bacteria used in the sandwich ELISA. Some strains of Salmonella cholerasuis showed higher absorbances than non-Salmonella bacteria.

• IMMUNE NETWORK
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• v.15 no.1
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• pp.27-36
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• 2015

In the present study, we investigated the protection conferred by a live attenuated Salmonella enterica serovar Typhimurium (ST) strain against Salmonella Typhimurium, Salmonella Gallinarum (SG), and Salmonella Enteritidis (SE) infection in layer chickens. Birds were orally primed with the attenuated ST strain at 7 days of age and then boosted at 4 weeks post prime immunization (PPI). Sequential monitoring of plasma IgG and mucosal secretory IgA (sIgA) levels revealed that inoculation with ST induced a significant antibody response to antigens against ST, SE, and SG. Moreover, significant lymphoproliferative responses to the 3 Salmonella serovars were observed in the immunized group. We also investigated protection against virulent ST, SE, and SG strain challenge. Upon virulent SG challenge, the immunized group showed significantly reduced mortality compared to the non-immunized group. The reduced persistence of the virulent ST and SE challenge strains in the liver, spleen, and cecal tissues of the immunized group suggests that immunization with the attenuated ST strain may not only protect against ST infection but can also confer cross protection against SE and SG infection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1163-1166
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• 2002

Antimicrobial activity of silver ion was tested against 3 kinds of food-borne microorganisms-Salmonella typhimurium, Staphylococcus aureus and Vibrio parahaemolyticus-using paper disk and broth medium methods. In paper disk method, silver ion showed antimicrobial activity against S. typhimurium and V. parahaemolyticus at the concentration above 2 ppm and 10 ppm, respectively, where as it was not detected in S. aureus with 20 ppm of silver ion concentration. In broth medium, the growth of S. typhimurium and V. Porahaemolyticus could be retarded at 0.3 ppm and 0.5 ppm of silver ion concentration respectively. In the presence of 1.0 ppm of silver ion, the growth of S. typhimurium was inhibited completely. In S. aureus, the growth was retarded at 5 ppm and was inhibited at l5 ppm completely.

• Korean Journal of Veterinary Service
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• v.24 no.1
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• pp.69-82
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• 2001

The result of studying the pathogenicity of Salmonella typhimurium and S enteritidis isolated from domestic animals in Gyeongbuk province were summarized as follows. In Congo-red binding test, S typhimurium had much more rough types than S enteritidis. In colicin production test, 4 strains of S typhimurium were positive but all of S enteritidis were negative. In hemolysin production test, all of S typhimurium and S enteritidis were negative. In Guinea pig serum resistant test, all of S typhimurium and S enteritidis were positive. As a result of pathogenicity test to mice, 54.4% of mice were died. Therefore, S typhimurium and S enteritidis were considered as highly pathogenic. S typhimurium DT104 and S enteritidis PT4 were more pathogenic to mice than other phage types of same serovar. S typhimurium and S enteritidis were considered not so pathogenic for 6-day-old chickens. The recovery rates of Salmonella stains from mice and chickens inoculated were 96.8%, and 54%, respectively. In chickens, proportional to the time from 2 weeks after challenge inoculation, the recovery rates were noticeably decreased.

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.501-510
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• 1994

This paper deals with the distribution, reservoir and mode of spread of infection on 6 hatcheries in Taegu, Kyungpook and 5 broiler farms in Kyungpook during the period from June 1991 to June 1992. Isolated Salmonella were examined for serotypes, biotyping of Salmonella(S) typhimurtum, antibiotic susceptibility and some biochemical characteristics. Forty two Salmonella strains were isolated from 42(2.7% of 1,577 caecal samples of chicks, and their serotypes were S typhimurium 10, S typhimurium var Copenhagen 5, S infantis 4, S thompson 3, and untypable 20. The isolation rate of Salmonella varied from 0 to 5.1% in 6 hatcheries and that of Salmonella from 5 broiler farms was 10. 5%. Biotypes of 10 S typhimurium and 5 S typhimurium var Copenhagen strains isolated from chicks of hatcheries and broiler farms were biotype 2(86.6%), 8(6.7%), and 10a(6.7%), and 26i(6.7%) according to Duguid's scheme. Antibiotic susceptibility test of Salmonella isolated were performed by agar dilution method, using 9 antibiotics as follows: ampicillin(Am), chloramphenicol(Cm), gentamicin(Gm), kanamycin(Km), nalidixic acid(Na), rifampicin(Rf), streptomycin(Sm), sulfadimethoxine(Su), and tetracycline(Tc), All the strains were sensitive to RF. But 8 strans(23.8%) were resistant to one or more drugs and the most common resistance patterns of transferred R plasmids were SmSuGm and SmSu. Among 42 isolates, one had transferable citrate utilizing plasmid. S typhimurium and S typhimurium var copenhagen strains were resistant to killing by 90% normal guinea pig serum.

• Korean journal of food and cookery science
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• v.20 no.4
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• pp.352-357
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• 2004

This study was performed to predict the multiplication growth patterns of Salmonella typhimurium according to the holding methods and times in cooked foods served at foodservice institutions. When simmered pork in soy sauce and ham and cucumber salad were inoculated with S. typhimurium (7.00 logCFU/g) and tested according to holding methods and times, room temperature holding showed a continuous increase in S. typhimurium count as time passed, whereas 80$^{\circ}C$ heating table sharply reduced the count to 4.00 (logCFU/g) after 2hrs of holding and to zero after 6hrs, which suggested that all S. typhimurium were destroyed. However, 5$^{\circ}C$ refrigerator holding showed a count increase, although it wasis still lower than that at room temperature and at 10$^{\circ}C$ cold table holding, which suggested that S. typhimurium is comparatively resistive to low temperature.

• Journal of Nutrition and Health
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• v.35 no.9
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• pp.926-931
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• 2002

The antimicrobial properties of extracts of Prunus mume were tested on Salmonella paratyphimurium and S. typhimurium. First, the Prumus mume was extracted with methanol at several temperatures, and then fractionation of the methanol extracts from Prunus mume was carried out by using petroleum ether, chloroform, ethyl acetate or butanol. Secondly, absorption column chromatoraphy (using a Diaion HP 20) was conducted to eliminate some water soluble materials that might inhibit the antimicrobial activity of some extracts. The antimicrobial activitry of each of the Prunus mume extracts was determined using a paper disc method against several food-borne pathogens, The growth inhibition curve was determine using butanol extracts of Prunus mume against Salmonella typhimurium. The extraction temperature did not have any significant effect on the yield of the extract or on the level of antimicrobial activity. The butanol extract of Prunus mume showed strong antimicrobial activity against Salmonella paratyphimurium and S. typhimurium; a 1,000 ppm of butanol extract of Prunus mume retared the growth of S. typhimurium up to 36 hours. (Korean J Nutrition 35(9) : 926~931, 2002)

• 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.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.76-77
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• 2005

Effects of dietary killed salmonella and vancomycin on the performance and immune response was investigated in broiler chicks inoculated with Salmonella typhimurium. During 3 week(27 d) of age, experimental diet did not affect daily gain, feed intake and feed efficiency. Dietary killed salmonella and vancomycin decreased MnSOD activity. At 7day after Salmonella typhimurium inoculation, dietary killed salmonella and vancomycin increased, daily gain and feed efficiency of broiler chicks. At 7 and 15 day after salmonella inoculation, dietary killed salmonella and vancomycin decreased erythrocyte peroxidase activity, but elevated proliferation of PBMC stimulated with LPS and supernatant IL-1 level secreted by the PBMC. The results suggested that dietary killed salmonella and vancomycin improved the performance of broiler chicks due to modulate antioxidant system and innate immune response of broiler chicks innoculated with Salmonella typhimurium.