The objectives of the current study were to evaluate the therapeutic effect of dioctahedral smectite (smectite) against calf diarrhea caused by pathogenic E. coli and/or Salmonella typhimurium. In this study, 20 calves (aged 2~3 months) with diarrhea were used for evaluation of the efficacy of smectite on calf diarrhea with 20% smectite suspension in PBS. Calves received 10 ml smectite suspension three times per day after feeding, and fecal samples were collected at the gate of treatment and on the first, second, third, fourth, and fifth day after administration. On the fifth day after treatment with smectite suspension, the diarrhea index showed a significant decrease in the treated group, compared to the control group (P<0.001). The number of pathogenic E. coli in feces of the treated group was significantly decreased, compared to each control group from the second day after treatment (P<0.001), and that of Salmonella typhimurium was significantly decreased from the first day after treatment (P<0.05). According to the results of the current study, 20% smectite suspension had a therapeutic effect on diarrhea caused by E. coli and/or Salmonella in calves.

Egg yolk immunoglobulin (IgY) is the antibody in egg yolk and can be produced in egg yolk by immunizing hens with antigens. IgY is functionally equivalent to mammalian IgG. It is found in the serum of the chicken and is passed from the mother chicken to the embryo via the egg yolk, a process that results in a high concentration of IgY in the egg yolk. The objective of this study was to evaluate the efficacy of specific IgY against enterotoxigenic Escherichia coli (ETEC) K99, Salmonella Typhimurium and Salmonella Choleraesuis that cause porcine bacterial diseases. To prepare specific IgY, Hy-Line Brown chickens were vaccinated with killed vaccine complex including E. coli K99, S. Typhimurium and S. Choleraesuis. The chicken egg yolk antibodies were purified from egg yolk by ammonium sulfate precipitation and the quality of the final preparation was confirmed by sodium dodecyl sulfate polyacrylamide gel electro-phoresis (SDS-PAGE). Titres of specific IgY in final preparations were measured by an enzyme-linked immunosorbent assay (ELISA). Antibody titers peaked at 3 weeks regardless the bacterial types and the similar patterns of immune response were observed for respective pathogens. In growth inhibitor test, specific IgY showed inhibitory effect on bacterial growth. After 0, 3, 6 and 12 hour of incubation with specific IgY (100 ㎍/㎖, 250 ㎍/㎖, 500 ㎍/㎖), there was a significant decrease in the growth (A 600nm ) of E. coli K99, S. Typhimurium and S. Choleraesuis compared to nonspecific IgY and controls. In BALB/c mice, the effect of specific IgY (100 ㎎/㎏, 250 ㎎/㎏) on bacterial challenges was investigated by intramuscular injection and oral administration of bacteria. Mice treated with specific IgY showed high survival rate though there was no significant differences on blood biochemichal examinations between treated and untreated groups. These results indicate the potential of specific IgY for the treatment of porcine bacterial diseases caused by E. coli K99, S. Typhimurium and S. Choleraesuis.

The acid value of the oil extracted from the three kinds of 15 fried foods ranged from 0.89 to 3.92, the peroxide value ranged 10.0～57.14 meg/㎏. Among the samples, popcorn chicken contained the highest crude fat content, showing 6.64± 0.26(%), while the french-fries showed 2.87±0.31(%), which was the lowest. The content of the trans fatty acid per 100 g of the foods were; the fried foods: 0.02～0.06 g. The french-fries contained the lowest saturated fatty acid per 100 g of the foods, showing 0.41～1.55 g, while the popcorn chicken showed the highest content, 1.16～3.43 g. The fried foods contained the highest linoleic acid content. Further, fried foods exhibited safe levels of trans fat content. The “School Zone”, which sells snacks, candies, chocolates flow, was not detected in the saccharin. Cookies, candies, chocolate was not detected in the tar colors. Aerobic plate count were ranged from 0∼4, 700 cfu/g in cookies, Salmonella test came out negative.

Salmonella spp. and Brucella spp. have caused a considerable disease of farmed animals and economic loss in animal farming and food industry. In this study, the disinfection efficacy of Vital-Oxidel®, a commercial disinfectant, composed to chlorine dioxide, betaine hydrochloride, and propylene glycol was evaluated against S. typhimurium and Brucella ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at 4oC. Vital-Oixdel® and test bacteria were diluted with distilled water (DW), hard water (HW) or organic matter suspension (OM) according to treatment condition. On OM condition, the bactericidal activity of Vital-Oixdel® against S. typhimurium and Brucella ovis was lowered compared to that on HW condition. As Vital-Oxidel® possesses bactericidal efficacy against animal pathogenic bacteria such as S. typhimurium and Brucella ovis, this disinfectant solution can be used to control the spread of bacterial diseases.

Salmonellosis constitutes an important public health problem in both developing and developed countries, including Korea. The aims of present study were to investigate the serovar and antimicrobial resistance of Salmonella isolated from food animals and animal products in slaughterhouses and farms. A total of 323 Salmonella were isolated from food animals (n=277) and meats (n=46) during 2010. Of the isolates, 21 different serovars were identified. The predominant serovars were S. Rissen (35%) and S. Montevideo (24.3) in healthy pigs, while S. Enteritidis (25.5%) in healthy chicken. S. Typhimurium (88.8%) was predominant in disease pigs, while S. Gallinarum (29.2%) and S. Montevideo (26.9%) were in diseased chickens. Among meat samples, S. Typhimurium (57.1%) was the most common serovar in pork but S. Enteritidis (38.7%) and S. Montevideo(32.3%) were in chikcen meats. Analysis of antimicrobial resistance patterns revealed that 20.7% of the isolates were sensitive to all the 15 drugs tested. The isolates were frequently resistant to nalidixic acid (47.7%), tetracycline (38.4%), streptomycin (33.7%), and ampicillin (32.8%). The resistance to quinolone and 3rd generation cephalosporins was higher in chicken and chicken meat isolates. Of the 323 isolates, 174 (53.9%) were resistant to one or more CLSI subclass, and 117 (36.2%) showed multiple-resistance. Our findings showed that multiple resistant Salmonella organism are widespread in animals and animal products in Korea. To prevent the transmission or exposure for consumers of antimicrobial resistant Salmonella, policies and guidelines aiming at prudential use of critical antimicrobials for humans are needed.

Random amplified polymorphic DNA (RAPD) and fluorescent amplified fragment length polymorphism (FAFLP) analyses were executed on a total of 28 Salmonella spp., including 6 ATCC reference strains, 2 isolates from outbreaks of food poisoning in Gwangju, and 20 isolates from carcasses. For RAPD analysis, four primers, named P1254, 23L, OPA-4, OPB-17 were used producing amplification fragments ranged from 0.18kb to 2.6kb. As a result, 5 types using P1254, 5 types using 23L, 3 types using OPA-4, and 6 types using OPB-17 and a total of 18 RAPD types were achieved. For FAFLP analysis, bacterial genomic DNA was digested with endonucleases EcoRⅠ and MseⅠ, site-specific adaptors were ligated, and PCR amplification was carried out with an EcoR1 adaptor-specific primer labelled with fluorescent dye. Amplified fragments, which were separated on a polyacrylamide sequencing gel ranged from 35bp to 300bp were analysed. Results were displayed as a dendrogram with genetic distance. Twenty two Salmonella isolates and 6 reference strains were divided into 14 groups in a level of 0.136 genetic distance. In conclusion, Salmonella isolates of chicken carcasses have different genetic properties when compared to reference strains and isolates from outbreak of food poisoning.

A greening phenomenon has been observed in some plant foods such as chestnut, sweet potato,burdock, and others during processing. The formation of the pigments was postulated as reactions of primary amino compounds with chlorogenic acid or caffeic acid ester, yielding acridine derivatives. Acridine derivatives have been regarded as mutagenetic agents. For the reason, the bacterial reverse mutation test was carried out to evaluate the genotoxicity of green pigment using Salmonella typhimurium TA98 and TA100. Alanine, arginine, aspartic acid, glycine,lysine, and phenylalanine were reacted repectively with chlorogenic acid to synthesize model compound. Green pigment was extracted from sweet potato. Maximum concentration of 2 and 50 mg/plate was tested for the synthetic green pigments and extracted green pigment respectively, taking bacterial survival, solubility, and color intensity into consideration. There was no signigicant increase in the reverse mutation either with or without S9 activation system by any test material. Though further studies with other genotoxicity test system are necessary, both synthetic and sweet potato green pigments seemed not to cause mutation despite the acridine moiety in their structures.

The present study was investigated the antibacterial effect of several sodium salts and the sodium salt mixture composed with sodium chlorate, sodium azide and sodium cyanide on Salmonella gallinarum (S. gallinarum) infection in murine derived macrophage RAW 264.7 cells. In the infection assay of S. gallinarum in macrophage cells pretreated with 15 mM sodium chlorate, 0.3 mM sodium cyanide, 0.3 mM sodium azide and the sodium salt mixture (15 mM sodium chlorate, 0.3 mM sodium cyanide, 0.3 mM sodium azide), respectively, the numbers of S. gallinarum in all treated-groups tended to decrease in the process of time after treatment, but the group treated with sodium cyanide was no significant difference compared with control. After 24 hours of treatment, the number of S. gallinarum in sodium azide (p<0.05), sodium chlorate (p<0.001) and the sodium salt mixture (p<0.001) treated-group was significantly decreased compared with control, and that in the sodium salt mixture treated-group was decreased the higher than all groups. The results of this study demonstrated that the sodium salt mixture composed with sodium chlorate, sodium azide and sodium cyanide, has the antimicrobial activity for S. gallinarum and may be beneficial on the control of intracellular pathogens.

Salmonellosis is a major bacterial zoonosis that causes self-limited enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans. Multidrug-resistant strains of Salmonella spp. has increased over the last several decades and recently causes more serious problems in public health. The present study was investigated bacteriocidal effects of sodium chlorate, sodium azide, sodium cyanide, and sodium salts mixture containing sodium chlorate, sodium azide, and sodium cyanide on infection with S. typhimurium in macrophage RAW 264.7 cells, and antibacterial effects of sodium salts mixture for murine salmonellosis. In infection assay of S. typhimurium in RAW 264.7 cells, bacterial survival rates within macrophage in all treated groups was significantly reduced comparing to that of the control group with the passage of incubation time. Administration of sodium salts mixture showed a therapeutic effect for S. typhimurium infected ICR mice. The mortality of mice treated with sodium salts mixture was 70% until 12 days, while that of control mice was 100% until 9 days after S. typhimurium infection. The results of this study strongly indicate that sodium salts mixture has a potency treatment for murine salmonellosis.

In this study, two duplex real-time PCR approach with melting curve analysis is presented for the detection of Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus, which are important food-borne bacterial pathogens usually present in fresh and/or minimally processed vegetables. Reaction conditions were adjusted for the simultaneous amplification and detection of specific fragments in the β-glucuronidase (uidA, E. coli), thermonuclease (nuc, S. aureus), hemolycin (hly, L. monocytogenes) and tetrathionate reductase (ttr, Salmonella spp.) genes. Melting curve analysis using a SYBR Green I real-time PCR approach showed characteristic Tm values demonstrating the specific and efficient amplification of the four pathogens; 80.6 ± 0.9 ℃,86.9 ± 0.5 ℃, 80.4 ± 0.6 ℃ and 88.1 ± 0.11 ℃ for S. aureus, E. coli O157:H7, L. monocytogenes and Salmonella spp.,respectively. For all the pathogens, the two duplex, real-time PCR was equally sensitive to uniplex real-time PCR,using same amounts of purified DNA, and allowed detection of 10 genome equivalents. When our established duplex real-time PCR assay was applied to artificially inoculated fresh lettuce, the detection limit was 10³ CFU/g for each of these pathogens without enrichment. The results from this study showed that the developed duplex real-time PCR with melting curve analysis is promising as a rapid and cost-effective test method for improving food safety.

Salmonellosis is the commonest zoonosis worldwide that generally causes enterocolitis and foodborne poisoning which represents a considerable public health burden. Salmonella spp. are potential enteric pathogens and intracellularly replicates in host cells resulting in chronic infections. The medical treatments for salmonellosis have been difficult yet and had a serious problem including the increasing emergence of antibiotic resistance. The present report was designated to investigate the antibacterial effects of Saururus chinensis Baill ethanol extract (SCEE) on pure culture and infection with Salmonella enterica serovar Typhimurium (S. typhimurium) in murine derived macrophage RAW 264.7 cells. In determination of antibacterial activity of SCEE against S. typhimurium, bacterial viability was markedly decreased compared to the control. Also, SCEE significantly induced morphological change (p<0.05) of RAW 264.7 cells. In infection assay of S. typhimurium in RAW 264.7 cells pretreated with 100㎍/㎖ of SCEE, which is a non-cytotoxic concentration, bacterial uptake ability of macrophage was increased corresponding with morphological change, whereas bacterial survival rates within macrophage were markedly reduced compared with untreated control. Furthermore, nitric oxide (NO) production in SCEE-treated cells was slightly increased until 2 h but showed a tendency of decrease after 4 h until 24 h post infection compared with untreated control with S. typhimurium infection. Taken together, these findings demonstrated that SCEE has the antibacterial activity for S. typhimurium and the protective effects against S. typhimurium infection through activating murine macrophage independent on NO, suggesting that SCEE may be beneficial on the disease caused by intracellularly replicating pathogens as a safe alternatives of conventional chemotherapies.

살모넬라증은 대표적인 인수공통전염병의 하나로서 세포내 기생하며 질병을 유발하며 장염과 식중독 등을 유발하여 공중보건학적으로 심각한 문제를 야기하고 있다. 본 연구는 삼백초의 수용성 추출물을 (SCWE) 이용하여 숙주세포에 대한 안전성, S. typhimurium 균에 대한 항균효과 및 대식세포 내 균 증 식억제 기능을 규명하였다. 본 실험을 통하여 SCWE 1, 10 및 100 μg/ml 농도로 첨가한 배지에서 RAW 264.7 체포와 24 시간 반응 후 평가해본 결과 세포독성이 인정되지 않았으며, S. typhimurium 균에 대하여 시간 경과에 따라 항균효과가 증가되는 것을 확인하였고, SCWE 처리에 의해 대식세포의 형태적 변화가 증가되는 것으로 나타났으며 (p<0.05), 살모넬라균의 탐식능력 및 대식세포 내 균 증식 억제 능 력이 비 처리군에 비해 현저히 증가되는 것이 확인되었다. 또한 SCWE 처리 한 대식세포에 살모넬라균 감염을 수행하였을 때 대식세포의 nitric oxide (NO) 산생능력이 비 처리 군에 비해 저하되는 것으로 나타나, 살모넬라균에 의한 대식세포의 세포독성을 억제하는 것으로 나타났다. 종합적으로 SCWE의 숙 주세포에 대한 안전성, 살모넬라균에 대한 항균효과 및 대식세포 내 균 증식 억제 효과가 있는 것으로 나타나 SCWE를 이용한 세포내 기생세균의 치료제 개발이 가능할 것으로 판단된다.

The present study was undertaken to estimate the antibacterial effect of a combination of C. rhizoma,L. Flos, and P. japonica (1:1:1) extracts (CLP1000) and a combination of the herbal extract mixture and dioctahedral smectite (CLPS1000) against murine salmonellosis. At the concentration of CLP1000 and CLPS10000.5 mg/ml, the antibacterial effect was not showed on Salmonella typhimurium (S. typhimurium). On the other hand,the antibacterial effect against S. typhimurium was observed at the concentration of CLP1000 and CLPS1000 1.0 mg/ml. Oral administration of Smectite, CLP1000, and CLPS1000 at the dose of 10 mg/ml showed a therapeutic effect for S. typhimurium infected BALB/c mice. The mortality of Smectite, CLP1000 and CLPS1000-treated mice was 90%,90%, and 70% at 12 days, respectively, while that of untreated mice was 100% at 9 days after a lethal dose of S. typhimurium infection. The results of our study strongly indicate that CLPS1000 has potential as an effective of salmonellosis.

In order to investigate phenotype and genotype of Salmonella enterica subsp. enterica serovar Enteritidis, Forty-eight S. Enteritidis isolates from diarrhea patients were analysed using antimicrobial resistance typing, Phage typing, and Pulsed field gel electrophoresis in Seoul from 2004 to 2005. All of S. Enteritidis were resistant to streptomycin(SM, 37.5%), ampicillin(AM, 43.8%), t icarcillin(TIC, 43.8%), chloramphenicol(CM, 29.2%), t etracycline(TE, 10 .4%) and nalidixic acid(NA, 18.8%) among 16 antimicrobial drugs. Of 48 S. Enteritidis, 8 isolates(16.7%) were resistant to 1 drug, 3 isolates( 6.3%) to 2 drugs, 1 isolate (2.1%) to 3 drugs and 17 isolates(35.7%) to 4 drugs. The basic pattern of 4 drugs resistance was SM, TIC, TE, and CM but 1 drug resistant isolates represent all nalidixic acid resistance. Among 30 antibiotic r esistant S . Enteritidis, 2 1 isolates(70 %) were phage type 2 1, 8 i solates(26.7%) were phage t ype 2 3 and 1 isolate( 3.3%) was RDNC, respectively. Of the phage types observed, all of phage type 23(8 isolates) were nalidixic acid resistant and phage type 21 were AM-TIC-SM-CM multi-resistance(13 isolates; 43.3%), AM-TIC-SM-TE(4 isolates; 13.3%), AM-TIC-SM(1 isolate; 3.3%), AM-TIC-CM(1 isolate; 3.3%), and AM-TIC(2 isolates; 6.7%) resistance and 1 isolate of RDNC was NA-TE resistance. PFGE divided the isolates into two major clusters, A(n=14) and B(n=14). There were four different resistance profiles with resistance to AM, TIC, SM, TE, NA within PFGE A. Also resistance to AM, TIC, SM, CM was common within PFGE B. The PFGE A strains typed as PT21(n=5), PT23(n=8), and RDNC(n=1), While all the PFGE B strains typed as PT21(n=14). In consequence, there was the highly significant concurrence between resistance typing, phage typing and PFGE.

In order to investigate the resistance patterns and molecular characteristics of resistance gene of 9 NA-resistant Salmonella enterica subsp. enterica serovar Enteritidis, Total of 101 isolates were isolated from stool sampes from 2005 to 2006. Among them, 48 isolates(47.5%) were identified S. Enteritidis, 24 isolates(23.8%) S. Typhi, 8 isolates(42.5%) S. Typhimurium, 7 isolates(6.9%) S. Paratyphi A and 14 isolates (13.9%) others Salmonellas. All of S. Enteritidis were resistant to ampicillin(43.8%), ticarcillin(43.8%), streptomycin(37.5%), chloramphenicol(29.2%), tetracycline(10.4%) and nalidixic acid(18.8%), respectively. All nalidixic acid-resistance isolates represented one point mutation in the quinolone resistance determining region(QRDR) of gyrA gene. Among them, 8(89%) isolates were substituted Tyr for Ser at position amino acid 83th or 1(11%) isolate was substituted Asn for Asp at position amino acid 87th. In consequence, Continued surveillance of NA-resistance among non-Typhi S. entetica isolates is needed to mitigate the increasing prevalence of nalidixic acid resistance.

Biological organisms require iron for optimal metabolism. Intracellular pathogens also must secure iron especially during infection of animal hosts expressing NRAMP(natural resistance-associated macrophage protein), a transporter protein sequestering metal ions from pathogens. This study shows that extracytoplasmic function sigma factor σE is required for Salmonella virulence in NRAMP1-expressing mice, and further shows that iron deprivation turns on σE expression of Salmonella. The virulence of σE -deficient Salmonella is completely attenuated in C3H/HeN mice while wild type Salmonella kills all mice. Addition of an iron-chelator DTPA(Diethylene triamine pentaacetic acid) to culture media induces σE expression of Salmonella, but iron supplementation abrogates this induction. These findings suggest that iron limitation in host macrophages can trigger σE -dependent virulence system of Salmonella that may include bacterial iron homeostasis.

국내산 과일 주스 4종을 준비하고 식중독 유발균인 Listeria monocytogenes와 Salmonella Typhimurium를 접종하여 14일 동안 4℃에서 보관하며 항균 효과를 살펴본 결과 다음과 같은 결론을 얻었다. L. monocytogenes 에서는 매실 주스가 가장 뛰어난 효과를 나타내어 보존 14일만에 생존하고 있는 균을 전혀 측정할 수 없었으며, 그 다음으로 키위가 3.0 log만큼 억제를 보이는 항균 효과를 나타내었다. 감귤의 경우 1.0 log만큼 억제하는데 그쳤다. 매실주스 10%를 다른 주스에 혼합하였을 때 L. monocytogenes는 키위 즙에서 더욱 향상된 항균 효과를 나타내어 14일 후 생존 균을 측정할 수 없었고, 감귤주스에서도 1.5 log 만큼의 향상된 항균 효과를 나타내었다. S. Typhimurium은 전반적으로 L. monocytogenes 보다 더 쉽게 억제되는 경향을 보였다. 키위 즙과 매실 주스에서 접종한 모든 균이 보존 14일 후 생존하지 않는 것으로 관찰되었으며, 감귤의 경우에는 1.4 log 만큼밖에 억제하지 못했다. 10%의 매실과 혼합된 주스에 S. Typhimurium을 접종한 결과 키위 즙에서는 접종한 전 균이, 감귤주스에서는 3.2 log 만큼의 증가된 억제효과를 나타내었다. 이상과 같은 결과로 볼 때, 매실은 식중독 유발균에 대한 강한 항균 활성을 가지고 있으며 다른 과실주스에서의 식중독을 예방하기 위한 식품 보존 첨가제로서 사용이 가능할 것으로 기대된다.

Intracellular pathogens must maintain redox homeostasis against the antimicrobial actions of reactive oxygen and nitrogen species produced by host cells. This study proves that glutathione is required to promote survival of an enteric pathogen Salmonella under the conditions producing reactive oxygen or nitrogen species. Glutathione is the non-protein thiol compound distributed in a variety of organisms and possesses strong electron-donating capability to reduce intracellular redox environment. To examine the role of glutathione on Salmonella redox homeostasis under oxidative and nitrosative stress conditions, gshB gene encoding glutathione synthetase was mutated by the one-step PCR inactivation method. The growth of gshB mutant Salmonella producing virtually no glutathione was greatly impaired in the culture media containing either hydrogen peroxide or nitric oxide donors. The results suggest that physiological levels of glutathione can provide a fundamental capability to maintain redox homeostasis for Salmonella in surviving oxidizing conditions of host cells.