Kun-Ho Seo

Konkuk University, Sŏul, Seoul, South Korea

Are you Kun-Ho Seo?

Claim your profile

Publications (58)76.67 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Lactobacillus kefiranofaciens is an indicator microorganism for kefir and a key factor in kefir grain formation and kefiran production. We designed a novel real-time PCR primer and probe set, LKF_KU504, for the rapid detection of L. kefiranofaciens. In inclusivity and exclusivity tests, only 14 L. kefiranofaciens strains were positive among 61 microorganisms, indicating 100 % sensitivity and specificity. The LKF_KU504 set also differentiated kefir milk from 30 commercial nonkefir yogurts. The levels of L. kefiranofaciens in kefir grain and kefir milk were significantly different, indicating L. kefiranofaciens was more concentrated in kefir grain than in kefir milk.
    Journal of food protection 04/2015; 78(4):855-8. DOI:10.4315/0362-028X.JFP-14-329 · 1.80 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Bacillus cereus can cause emetic and diarrheal food poisoning. It is widespread in nature and therefore, considered a major foodborne pathogen. To develop a sensitive and reliable assay for detecting enterotoxin genes (nheA, entFM, hblD, cytK) and emetic toxin (ces), specific primers each targeting one individual gene were designed. Propidium monoazide (PMA) was coupled with the developed multiplex PCR (mPCR) for the detection of viable B. cereus. The inclusivity and exclusivity of the PMA-mPCR was confirmed using a panel of 44 strains including 17 emetic and 9 enterotoxic B. cereus reference strains and 18 non-target strains. The limit of detection (LOD) without PMA treatment in pure DNA was 2 pg/ reaction tube. The LOD of mPCR assay in pure heat-killed dead bacteria was 4.0 � 102 CFU/mL. Also, the LOD on the viable bacteria with or without PMA treatment was similar (3.8 � 102 CFU/mL) showing that the PMA treatment did not significantly decrease sensitivity. Finally, the newly developed PMA-mPCR successfully detected 4.8 � 103 and 3.6 � 103 CFU/g of viable B. cereus F4810/72 (emetic) and B. cereus ATCC 12480 (enterotoxic) reference strains, respectively, in food samples. Hence, this study combines PMA and mPCR to detect viable B. cereus with a wide range of toxin detection (5 toxins). Thus, the novel PMA-mPCR assay developed in this study is a rapid and efficient diagnostic tool for the monitoring of viable B. cereus in food samples and potentially other samples via appropriate DNA extraction.
    Food Control 03/2015; 55:151-157. DOI:10.1016/j.foodcont.2015.02.049 · 2.82 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The emergence of antibiotic-resistant foodborne Salmonella has become a major public health problem. Consumption of undercooked poultry contaminated with Salmonella can induce food poisoning in humans. In this study, we investigated the occurrence and antibiotic resistance patterns of Salmonella spp. isolated from 120 chicken carcasses produced in 6 poultry slaughterhouses in South Korea. A total of 11 samples (9.2%) were found contaminated with Salmonella: 5 isolates were serotyped as Salmonella Bellevue strain (slaughterhouse C) and 6 isolates were serotyped as Salmonella Enteritidis strain (slaughterhouse E). Salmonella Bellevue isolates were resistant to five antibiotics (ampicillin, chloramphenicol, nalidixic acid, tetracycline, and trimethoprim/sulfamethoxazole), while Salmonella Enteritidis isolates were resistant to nine antibiotics (ampicillin, cefotaxime, ceftazidime, cefazolin, cephalothin, amikacin, nalidixic acid, streptomycin, and tetracycline). All cephalosporin-resistant Salmonella Enteritidis isolates exhibited the extended-spectrum β-lactamase (ESBL) phenotype and carried the gene encoding CTX-M-15, the most prevalent ESBL enzyme worldwide. Based on molecular subtyping performed using the automated rep-polymerase chain reaction (PCR) system (DiversiLab), the isolates showing ≥95 similarity in their rep-PCR banding patterns were classified into 5 pulsotypes. Given that cephalosporins are the drugs of choice for invasive Salmonella infections, the high incidence of ESBL-producing strains in chicken should emphasize the necessity of regular monitoring of the occurrence of antibiotic-resistant ESBL-positive Salmonella strains in poultry meat.
    Foodborne Pathogens and Disease 02/2015; 12(3). DOI:10.1089/fpd.2014.1847 · 2.09 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The relationship between the intestinal microbiota and the hypocholesterolemic and anti-obesity effects of whole grape seed flour from white and red winemaking was evaluated. Male Golden Syrian hamsters were fed a high-fat (HF) control diet, or HF diet supplemented with 10% partially defatted grape seed flours from either Chardonnay (ChrSd) or Cabernet Sauvignon (CabSd) grapes for three weeks. The numbers of total bacteria and relative abundances of Bifidobacterium spp., Lactobacillus spp., and Firmicutes in feces were significantly lower while the relative abundance of Bacteroides fragilis was greater than the control from feeding the ChrSd diet. The ratio of Firmicutes/Bacteroidetes (F/B) was lower in ChrSd diet. There were significantly positive correlations between Lactobacillus spp., ratio of F/B and plasma total- and LDL-cholesterol and liver weight. The reduction of Lactobacillus spp. by the ChrSd diet was accompanied by inhibition of Farnesoid X receptor (FXR) signaling in the intestine as expression of intestinal fibrablast growth factor (FGF)15, positively regulated by FXR, was decreased. Expression of CYP7A1, negatively regulated by FGF15, was up-regulated in the liver, indicating that alteration of the intestinal microbiota may regulate bile acid and lipid metabolism. These findings suggest that beneficial health effects of Chardonnay grape seed flour on HF-induced metabolic disease relate in part to modulation of intestinal microbiota and their metabolic processes.
    Journal of Agricultural and Food Chemistry 01/2015; 63(5). DOI:10.1021/jf5026373 · 3.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The identity of 45 Hanwo and 47 imported beef (non-Hanwoo) samples from USA and Australia were verified using the microsatellite (MS) marker and single nucleotide polymorphism (SNP) methods. Samples were collected from 19 supermarkets located in the city of Seoul and Gyeonggi province, South Korea, from 2009 to 2011. As a result, we obtained a 100% concordance rate between the MS and SNP methods for identifying Hanwoo and non-Hanwoo beef. The MS method presented a 95% higher individual discriminating value for Hanwoo (97.8%) than for non-Hanwoo (61.7%) beef. For further comparison of the MS and SNP methods, blood samples were collected and tested from 54 Hanwoo x Holstein crossbred cattle (first, second, and third generations). By using the SNP and MS methods, we correctly identified all of the first-generation crossbred cattle as non-Hanwoo; in addition, among the second and third generation crossbreds, the ratio identified as Hanwoo was 20% and 10%, respectively. The MS method used in our study provides more information, but requires sophisticated techniques during each experimental process. By contrast, the SNP method is simple and has a lower error rate. Our results suggest that the MS and SNP methods are useful for discriminating Hanwoo from non-Hanwoo breeds.
    Hangug chugsan sigpum haghoeji = Korean journal for food science of animal resources 12/2014; 34(6):763-768. DOI:10.5851/kosfa.2014.34.6.763 · 0.25 Impact Factor
  • 12/2014; 38(4):79-83. DOI:10.13041/jpvm.2014.38.4.79
  • [Show abstract] [Hide abstract]
    ABSTRACT: Virus-like particles (VLPs) composed of the truncated capsid protein of swine hepatitis E virus (HEV) were developed and immune responses of mice immunized with the VLPs were evaluated. IgG titers specific for the capsid protein of swine HEV were significantly higher for all groups of mice immunized with the VLPs than those of the negative control mice. Splenocytes from mice immunized with the VLPs also produced significantly greater quantities of interferon (IFN)-γ than interleukin (IL)-4 and IL-10. These newly developed swine HEV VLPs have the capacity to induce antigen-specific antibody and IFN-γ production in immunized mice.
    Journal of Veterinary Science 12/2014; 15(4):575. DOI:10.4142/jvs.2014.15.4.575 · 1.14 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Chlorine bactericidal effects on Cronobacter vegetative cells and biofilms on conveyor belt chips were evaluated. Cronobacter vegetative cell isolates were inactivated after 10 min chlorine exposure (10 ppm). No efficacy difference was observed between pH-adjusted and pHunadjusted sodium hypochlorite solutions. The pH-adjusted solution was more effective at reducing the bacterial population in a biofilm. The number of cells in the biofilm on a Buna-N chip decreased by 3 log after exposure to 100 ppm of pH-adjusted chlorine and for PVC by 2.21 log after exposure to 400 ppm of pH-adjusted solution. The rate of biofilm reduction is dependent on the composition of the conveyor belt, concentration of chlorine, and pH of the chlorine solution.
    Food science and biotechnology 12/2014; 23(6). DOI:10.1007/s10068-014-0258-2 · 0.66 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A multiplex PCR assay for the rapid detection of B. cereus group, enterotoxic and emetic strains was developed. A panel of emetic and enterotoxic reference strains, B. cereus group members and non-target strains were used for the evaluation of the assay. Verification of PCR results on pure culture and inoculated foods successfully confirmed the specificity of approach for detection of target genes for B. cereus group (groEL), diarrheal (cytK, nheA, hblC, entFM) and emetic strains (CER). The sensitivity of approach was satisfying in pure culture as 20 pg of DNA per reaction tube. Artificial contamination of seven different food matrices with distinct bacterial counts revealed a minimum detection limit of 103 cfu/g in food samples. The detection limits were improved to approximately 101 cfu/g after 7 h enrichment. Natural contamination in rice and kimbab as well as environmental samples (soil, cow feces) was studied. The incidence of B. cereus was 63.88 and 38.88% in rice and kimbab, and 84.61 and 69.23% in soil and feces, respectively. To the best of our knowledge, this is the first time that an assay for simultaneous detection of B. cereus group, emetic and enterotoxic strains with such a wide range of detection target genes in food and environmental samples has been described.
    African journal of microbiology research 11/2014; 8(47):3821-3829. DOI:10.5897/AJMR2014.7416 · 0.54 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The detection ability and selectivity of Karmali agar was improved by supplementation of an extended-spectrum β-lactamase inhibitor, potassium clavulanate. The optimum concentration of potassium clavulanate (0.5 μg/ml) in Karmali agar was determined by inoculation of 50 Campylobacter and 30 extended-spectrum β-lactamase-producing E. coli strains onto normal and modified Karmali agar containing various concentrations of the agent. Eighty retail carcasses were rinsed with 400 ml of buffered peptone water. The rinse samples were enriched in 2 × blood-free Bolton enrichment broth at 42°C for 48 h and then were streaked onto normal and modified Karmali agar containing 0.5 μg/ml potassium clavulanate. The suspicious colonies were subcultured on Columbia blood agar and confirmed by colony PCR. In chicken carcass samples, the modified Karmali agar showed a significantly greater isolation rate than normal Karmali agar (42.5 versus 21.3%; P < 0.05). Furthermore, the selectivity of the modified Karmali agar was also significantly higher (P < 0.05) than that of the normal Karmali agar, as seen by comparison of the number of contaminated agar plates (83.8 versus 97.5%) and the growth index (1.67 versus 2.91) of the non-Campylobacter colonies.
    Journal of food protection 07/2014; 77(7):1207-11. DOI:10.4315/0362-028X.JFP-13-405 · 1.80 Impact Factor
  • 06/2014; 29(2):158-163. DOI:10.13103/JFHS.2014.29.2.158
  • [Show abstract] [Hide abstract]
    ABSTRACT: We compared Bolton enrichment broth supplemented with antimicrobial triclosan (T-Bolton broth) and normal Bolton broth for the isolation of Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) from chicken carcass rinse. Whole chickens were rinsed with buffered peptone water prior to enrichment in normal Bolton broth or T-Bolton broth, followed by inoculation onto modified charcoal-cefoperazone-deoxycholate agar (mCCDA). Suspect colonies were confirmed by PCR. We observed a significantly higher number of C. jejuni or C. coli-positive samples in the T-Bolton broth (71.3%) than in the normal Bolton broth (27.5%) (p<0.05). Furthermore, the number of contaminated mCCDA plates was lower after enrichment in T-Bolton broth (3.8%) than in the normal Bolton broth (75%) (p<0.05), indicating that T-Bolton broth has higher selectivity. Finally, we identified extended-spectrum β-lactamase-producing Escherichia coli as the predominant competing flora in normal Bolton broth. In conclusion, the use of T-Bolton broth results in significant elimination of competing bacteria.
    International journal of food microbiology 04/2014; 181C:37-39. DOI:10.1016/j.ijfoodmicro.2014.04.006 · 3.16 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The mechanisms for the hypocholesterolemic and anti-obesity effects of grape seed flours derived from white and red winemaking processing were investigated using male Golden Syrian hamsters fed high-fat (HF) diets supplemented with 10% partially defatted grape seed flours from Chardonnay (ChrSd), Cabernet Sauvignon (CabSd), or Syrah (SyrSd) pomace as compared to a HF control diet for three weeks. Hamsters fed the ChrSd diet had significantly lowered plasma total-, VLDL-, and LDL-cholesterol concentrations compared to the CabSd, SyrSd, and control. The improved plasma cholesterol after ChrSd was correlated with the up-regulation of hepatic genes related to cholesterol (CYP51) and bile acid (CYP7A1) synthesis as well as LDL-cholesterol uptake (LDLR). A reduction of hepatic lipid content was associated with altered expression of the genes related to lipid metabolism. However, fecal total lipid content was not changed. Expression of ileal apical sodium bile acid transporter (ASBT) was not affected by ChrSd, indicating unchanged ileal bile acid reabsorption. The anti-obesity effect of the ChrSd diet appears to be related to expression of adipogenesis- and inflammation-related genes in adipose tissue. These findings suggest that flavonoid-rich Chardonnay grape seed flour induced cholesterol-lowering, anti-obesity, and anti-inflammatory health benefits and attenuation of hepatic steatosis via regulation of gene expression related to cholesterol, bile acid, and lipid metabolism in liver and adipose tissue.
    Journal of Agricultural and Food Chemistry 02/2014; 62(8). DOI:10.1021/jf404832s · 3.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hepatitis E has traditionally been considered an endemic disease of developing countries. It generally spreads through contaminated water. However, seroprevalence studies have shown that hepatitis E virus (HEV) infections are not uncommon in industrialized countries. In addition, the number of autochthonous hepatitis E cases in these countries is increasing. Most HEV infections in developed countries can be traced to the ingestion of contaminated raw or undercooked pork meat or sausages. Several animal species, including pigs, are known reservoirs of HEV that transmit the virus to humans. HEVs are now recognized as an emerging zoonotic agent. In this review, we describe the general characteristics of HEVs isolated from humans and animals, the risk factors for human HEV infection, and the current status of human vaccine development.
    01/2014; 3(1):29-36. DOI:10.7774/cevr.2014.3.1.29
  • [Show abstract] [Hide abstract]
    ABSTRACT: We compared Bolton enrichment broth supplemented with antimicrobial triclosan (T-Bolton broth) and normal Bolton broth for the isolation of Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) from chicken carcass rinse. Whole chickens were rinsed with buffered peptone water prior to enrichment in normal Bolton broth or T-Bolton broth, followed by inoculation onto modified charcoal-cefoperazone-deoxycholate agar (mCCDA). Suspect colonies were confirmed by PCR. We observed a significantly higher number of C. jejuni or C. coli-positive samples in the T-Bolton broth (71.3%) than in the normal Bolton broth (27.5%) (p < 0.05). Furthermore, the number of contaminated mCCDA plates was lower after enrichment in T-Bolton broth (3.8%) than in the normal Bolton broth (75%) (p < 0.05), indicating that T-Bolton broth has higher selectivity. Finally, we identified extended-spectrum β-lactamase-producing Escherichia coli as the predominant competing flora in normal Bolton broth. In conclusion, the use of T-Bolton broth results in significant elimination of competing bacteria.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to compare the performance of a standard culture method and polymerase chain reaction (PCR) for the detection of Staphylococcus aureus (S. aureus) in milk and meat products. Milk, dried infant formula, sausage and ground beef that had been artificially inoculated with S. aureus were enriched in tryptic soy broth. After the enrichment, a loopful was inoculated onto Baird-Parker agar with egg-yolk-tellurite. In parallel, 23S rRNA was amplified by PCR from samples of the enriched broth. Suspected S. aureus colonies grown on selective agars were finally confirmed by a coagulase test and colony PCR. No significant statistical differences were observed between the incidence of S. aureus detected by the culture method and the incidence detected by PCR, in milk or dried infant formula. However, in sausage and ground beef, the number of positives detected by PCR was significantly higher than by the culture method (p
    12/2013; 45(6). DOI:10.9721/KJFST.2013.45.6.791
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine the prevalence of Salmonella serotype Enteritidis in eggs in South Korea, we conducted a microbiological survey of commercially available eggs produced in conventional or organic farms during the period from 2010 to 2012. The contents of 7,000 raw shell eggs (6,000 of conventional and 1,000 of organic origin) were examined to evaluate the extent and type of Salmonella Enteritidis contamination. A total of 26 salmonellae (7.4% of all pooled samples) were isolated from 350 homogenized pools, each containing the contents from 20 eggs. An unexpected and particularly surprising finding was that all the Salmonella isolates were serotyped as Salmonella Gallinarum. Salmonella Gallinarum was more common in eggs from organic farms: 10 of 50 egg pools (20.0%) from organic and 16 of 300 egg pools (5.3%) from conventional farms tested positive for Salmonella Gallinarum. However, organic and conventional isolates showed similar antimicrobial susceptibilities. All the isolates and a vaccine strain, SG 9R, which has been widely used in South Korea, were further characterized using the automated repetitive sequence-based PCR (rep-PCR) system, DiversiLab, to ascertain the molecular subtypes and to identify differences from the vaccine strain. The rep-PCR identified 2 distinct clusters among the 26 Salmonella Gallinarum isolates with a greater than 96% similarity index. These were clearly differentiated from the vaccine strain, SG 9R, with which there was a less than 86% similarity index. We found there was low genetic heterogeneity among isolates within each cluster and were able to distinguish wild type strains from the live vaccine strain (SG 9R) using the DiversiLab system.
    Poultry Science 10/2013; 92(10):2789-97. DOI:10.3382/ps.2013-03175 · 1.54 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The effect of hydroxypropyl methylcellulose (HPMC) on hepatic gene expression was analyzed by exon microarray and real-time PCR from livers of diet-induced obese (DIO) mice fed a HF diet supplemented either 6% HPMC or 6% microcrystalline cellulose (MCC). HPMC-fed mice exhibited significantly reduced body weight gain (55% lower compared to MCC), liver weight (13%), plasma LDL-cholesterol concentration (45%), and HF diet-increased intestinal permeability (48%). HPMC significantly reduced areas under the curve for 2-h insulin and glucose responses indicating enhanced insulin sensitivity and glucose metabolism. HPMC upregulated hepatic genes related to fatty acid oxidation, cholesterol and bile acid synthesis, cellular activation of glucocorticoid (bile acid recycling), and downregulated genes related to oxidative stress, triglyceride synthesis, and polyunsaturated fatty acid elongation. In conclusion, HPMC consumption ameliorates the effects of a HF diet on intestinal permeability, insulin resistance, hepatic lipid accumulation, glucocorticoid-related bile acid recycling, oxidative stress, and weight gain in DIO mice.
    Journal of Agricultural and Food Chemistry 06/2013; 61(26). DOI:10.1021/jf400545w · 3.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: [This corrects the article DOI: 10.1016/j.phrp.2012.12.005.].
    06/2013; 4(3):176. DOI:10.1016/j.phrp.2013.05.002
  • [Show abstract] [Hide abstract]
    ABSTRACT: Canine distemper virus (CDV) causes highly contagious respiratory, gastrointestinal, and neurological diseases in wild and domestic animal species. Despite a broad vaccination campaign, the disease is still a serious problem worldwide. In this study, six field CDV strains were isolated from three dogs, two raccoon dogs, and one badger in Korea. The full sequence of the genes encoding fusion (F) and hemagglutinin (H) proteins were compared with those of other CDVs including field and vaccine strains. The phylogenetic analysis for the F and H genes indicated that the two CDV strains isolated from dogs were most closely related to Chinese strains in the Asia-1 genotype. Another four strains were closely related to Japanese strains in the Asia-2 genotype. The six currently isolated strains shared 90.2-92.1 % and 88.2-91.8 % identities with eight commercial vaccine strains in their nucleotide and amino acid sequences of the F protein, respectively. They also showed 90.1-91.4 % and 87.8-90.7 % identities with the same vaccine strains in their nucleotide and deduced amino acid sequences of the H protein, respectively. Different N-linked glycosylation sites were identified in the F and H genes of the six isolates from the prototype vaccine strain Onderstepoort. Collectively, these results demonstrate that at least two different CDV genotypes currently exist in Korea. The considerable genetic differences between the vaccine strains and wild-type isolates would be a major factor of the incomplete protection of dogs from CDV infections.
    Virus Genes 04/2013; 47(1). DOI:10.1007/s11262-013-0916-0 · 1.84 Impact Factor

Publication Stats

193 Citations
76.67 Total Impact Points

Institutions

  • 2007–2014
    • Konkuk University
      • College of Veterinary Medicine
      Sŏul, Seoul, South Korea
  • 2008
    • University of Maryland, College Park
      Maryland, United States