• Journal of Microbiology
• /
• v.42 no.1
• /
• pp.14-19
• /
• 2004

Salmonella enterica serovar Typhimurium DT104 (Salmonella Typhimurium DT104 or DT104) has been emerging as a common pathogen for human in Korea since 1997. In order to compare the genomic relationship and to search for the dominant strains in Korea, we conducted pulsed-field gel electrophoresis (PFGE) and IS200 fingerprinting of 25 epidemiological unrelated isolates from human and animals from Korea and cattle from America. Two Salmonella Typhimurium DT104 isolates from human in Korea and all 8 isolates from American cattle had indistinguishable patterns from the PFGE and IS200 fingerprinting but multidrug-resistant Salmonella Typhimurium isolates, including DT104, from Korean animals had diverse genetic patterns. The data suggest that a dominant DT104 strain might have circulated between Korean and American cattle and that it had a high level of clonality.

• Journal of Microbiology
• /
• v.44 no.3
• /
• pp.327-335
• /
• 2006

An epidemiological survey of human enterobacterial infections was conducted to determine the prevalence of enteropathogens in the Republic of Korea during one year, 2003. We tested for infectious diseases in 26,992 stool samples obtained from people who visited clinics located in six big cities and six rural provinces. From these samples, we isolated 1,291 cases of enteritis bacterial infection (4.8%). In the urban areas, 821 cases of bacterial infection (6.4%) were identified and, in the rural areas, 479 bacterial strains (3.3%) were isolated. Seasonal patterns were seen for diarrhea associated with S. aureus, S. coli and V. parahaemolyticus, while Salmonella and Shigella infections showed slight seasonal variation. We found that S. aureus and Salmonella were more frequently isolated from children and the elderly; however, the prevalence of E. coli, V. parahaemolyticus, and Shigella were similar in different age groups. Routine monitoring of these infections is considered a worthwhile means by which to elucidate their epidemiology and modes of transmission and ultimately to control them more effectively. Continuous laboratory-based surveillance for findings of enteritis bacterial infection should be emphasized in the prevention of these infections.

• Journal of Microbiology and Biotechnology
• /
• v.13 no.1
• /
• pp.155-158
• /
• 2003

In early 2002, over 200 people in the city of Pusan. Korea suffered from paratyphoid fever resulting from Salmonella Paratyphi A Infection. Antimicrobial susceptibility tests and Xbal pulsed-field gel electrophoresis (PFCE) were conducted to 54 Salmonella Paratyphi A isolated from humans during the period of 1998 to 2002. Most of the isolates ($83\%$) were only nalidixic acid-resistant and $78\%$ were X 1 PFGE patterns. Also, we measured the MIC of ciprofloxacin and screened gyrA mutation(5) using allele- specific PCR and restriction fragment length polymorphism (AS-PCR-RFLP). The representative 5 isolates in 2002 and 1 isolate in 2000 were $1{\mu}g/ml$ of MIC and had mutation at the 83rd codon in gyrA. These data suggest that the outbreak in the early 2002 might have been due to dissemination of the strain present In 2000. Also, decreased susceptibility to ciprofloxacin was partly due to the mutation at the 83rd codon in gyrA.

• Journal of Microbiology
• /
• v.34 no.1
• /
• pp.95-100
• /
• 1996

The effect of the extracellular protease of Salmonella schottmulleri on human serum constituents such as immunoglobulins, hemoglobin and lysozyme and tissue constituents such as fibronectin and collagens was investigated. This protease degraded collagens (type I and III), fibronectin and serum proteins such as human hemoglobin and lysozyme. Bovine serum albumin was degraded slightly. Thus, the present study suggested the possibility that this protease is not only played an important role in invasion of S. schottmulleri by degrading the constituent proteins such as collagens and fibronectin but also induced complications observed in septicemia and chronic infections by degrading the serum proteins. This protease is also capable of degrading defence-oriented humoral proteins, immunoglobulins (IgG and IgM). Furthermore, it is toxic to HEp-2 cells. These findings clarified the possible role of Salmonella protease as a virulence factor in the pathogenesis of Salmonella infections.

• Korean Journal of Poultry Science
• /
• v.45 no.1
• /
• pp.1-15
• /
• 2018

Salmonella infections in livestock industry cause various problems such as worsening animal welfare and productivity, damaging consumer confidence in the food safety of animal products. Chicken meat and eggs are known as major source of pathogen causing human foodborne infections. Therefore food safety concerns have prompted the poultry producers and governments to introduce the strategy and regulation to control these pathogens. Salmonella can persist for long periods of time in a wide range of spaces including feed bin, feed processing facilities, poultry farm, slaughterhouse, processing plants, etc. For the effective and constant Salmonella control, combination of pre-harvest, harvest and post-harvest measures should be considered comprehensively. The control measures would be most effective at farm level where the contamination initiates. Transmission of pathogen from feed origin to the live poultry and finally to the products was proven already. To control bacteria in the feed ingredients and formula feed, thermal processing, irradiation or chemical treatment may be applied. Chemical treatments to inhibit Salmonella in the feed involve the use of products containing organic acids, formaldehyde, or a combination of such compounds. However, recontamination which might occur during storage and transport process and/or by other various factors should always be under control and eliminated. Feed additives used to control Salmonella in birds' gastrointestinal track can be of various types, including prebiotics, probiotics, organic acids and bacteriophages. Although their mode of action varies, they ultimately inhibit the colonization of Salmonella in the gut and improve the performance of birds. This review describes the strategies that could be adapted to the management of feedstuffs and the use of feed additives in pre-harvest stage to control Salmonella contamination in poultry farming.

• Korean Journal of Veterinary Research
• /
• v.62 no.2
• /
• pp.14.1-14.5
• /
• 2022

Salmonella enterica serotype Choleraesuis causes swine paratyphoid, with clinical findings of enterocolitis and septicemia. However, the clinicopathological features of S. Choleraesuis infections in pigs have not been reported in Korea. We describe the pathological findings of two weaned pigs with S. Choleraesuis infections, presenting with diarrhea, cough, and sudden death. Pathological examination indicated severe necrotic colitis in pig 1 and septicemic lesions in pig 2. Multidrug-resistant S. Choleraesuis was isolated from the pigs' lungs and intestinal contents. Further research is required for the surveillance of S. Choleraesuis infections in pigs and the virulence estimation in the S. Choleraesuis isolates.

• Korean Journal of Poultry Science
• /
• v.40 no.3
• /
• pp.277-281
• /
• 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 Veterinary Service
• /
• v.30 no.3
• /
• pp.339-351
• /
• 2007

Salmonella infections cause the diseases in poultry and some zoonotic Salmonella can be transmitted to human through poultry products, resulting in food-borne disease. This study was conducted to obtain some useful information for the control of salmonellosis in human. Twenty four Salmonella spp were isolated from poultry carcasses, and they were examined with several methods such as serotyping, antimicrobial resistance test and random amplified polymorphic DNA(RAPD) to identify their characteristics. In serotyping test of 24 strains S enteritidis was 17 (70.8%), followed by S schwarzengrund 3 (12.5%), untyped strain 4 (16.7%). In the results of antimicrobial resistance test, 23 (95.8%) isolates were resistant to at least one antimicrobial agent, generating eight different resistance patterns. In RAPD analysis using URP-6 primer to differentiate Salmonella isolates within a serotype, 4 serogroups were divided into 10 RAPD types: 5 types in S enteritidis, 2 types in S schwarzengrund and 3 types in the remainder.

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

• Natural Product Sciences
• /
• v.17 no.4
• /
• pp.296-302
• /
• 2011

We determined the inhibitory activity of the essential oil fraction obtained by steam distillation from the fresh and dried leaves of Perilla frutescens var. acuta against some pathogenic Salmonella and Vibrio spp. The activities of compounds isolated from the essential oils, apiol and myristicin, were also tested and the results were compared with those of the essential oil fraction. The Perilla essential oil fraction and its main components showed significant inhibition against antibiotic-susceptive and antibiotic-resistant strains of the tested Salmonella and Vibrio strains. Synergistic or additive effects were identified by combing the oils with ampicillin by checkerboard-titer tests. We conclude that essential oils from P. frutescens can be useful in the treatment of Salmonella and Vibrio infections and as safe additives to food materials for the prevention of contamination of food by these bacteria. This is especially important because of the rapid increase in antibiotic-resistant strains, which could cause severe symptoms in humans.