• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1016-1024
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• 2000

The study was conducted to develop a rapid method for the detection of Listeria monocytogenes in foods via polymerase chain reaction (PCR) technique using hemolysin gene (hlyA) primers. Specificity and sensitivity of PCR, optimal conditions for PCR and application of hlyA gene primers for the detection of L. monocytogenes from milk and beef were investigeted. Each of the 20 L. monocytogenes strains gave a single 713 bp band, but other Listeria sup. and other bacteria did not show any bands. As few as 1 pg of L. monocytogenes DNA or 2.4$\times$10$^4$L. monocytogenes cells could be detected with hlyA gene primers. PCR product was most improved at 20~30 cycle in terms of removal of tailing and sensitivity. Also, the sensitivity was significantly improved by the further 10~15 cycle after 20 cycle PCR amplication. Milk (10 mL) and beef (10 g) samples were inoculated with L. monocytogenes at the concentrations ranging from 0 to 10$^{7}$ CFU/mL or g to determine the best sensitivity of PCR for the rapid detection of L. monocytogenes. PCR assay could detect 2 cells in milk with repeating PCR amplication and 2.6$\times$10$^2$cells in beef sample after 24 hr enrichment growth at 35$^{\circ}C$ in LEB.

• Korean Journal of Microbiology
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• v.41 no.4
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• pp.269-274
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• 2005

We evaluated the PCR assay and two commercialized PCR kits for the detection of mycoplasma in veterinary via live vaccines. The PCR assay could specifically detect all the tested Mycoplasma spp. and Acholeplasma spp., whereas two commercialized PCR kits did not. Also, the specificity of the PCR assay showed that 4 reference strains and 7 field isolates belonging to avian mycoplasma species could be all detected. The sensitivity of the PCR assay was determined using pure cultured Mycoplasma spp. and Acholeplasma spp. with a range of 1 to 100 colony forming units/ml in 9 CFR Mycoplasma broth. To test the availability of the PCR assay for veterinary live viral vaccines, A. laidlawii was artificially inoculated into the swine transmissible gastroenteritis-rota virus combined vaccine and canine parvovirus vaccine, respectively and the sensitivity of the PCR assay was similar with the result of cultured samples. In this study, the PCR assays could be used as rapid and sensitive methods for the detection of mycoplasma in veterinary live viral vaccines.

• Journal of Food Hygiene and Safety
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• v.18 no.1
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• pp.6-13
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• 2003

Various kinds of genetically modified organisms (GMO) and processed foods have been developed during recent years. Genetically modified organisms can be classified into several groups as their development methods. Generally, GMO has three foreign DNA regions such as gene expression adjustment region(Promoter), termination region (terminator) and structure gene. Detection of these regions can be done particularly by polymerase chain reaction (PCR). PCR-based detection can virtually be performed for any GMO within short of time. The most important prerequisite for the application of PCR-based detection is to decide abstraction method of efficient nucleic acids. Specially, in the case of processed food, because nucleic acids of foodstuffs are damaged by heat treatment (sterilization), pressure and fermentation, DNA must be extracted ken the samples prior to PCR analysis. Although many DNA extraction protocols are available, they have rarely been compared in a comprehensive method. In this study low widely used commercial and non-commercial DNA extraction methods-DNeasy$^{TM}$, Wizard$^{TM}$, CTAB, phenol/chloroform system-were compared with respect to the quality and yield of nucleic acids and insertion genes.nes.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.4
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• pp.371-377
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• 2008

Our precedent study has reported glass-PDMS (polydimethylsiloxane) based biochip for the gene PCR (polymerase chain reaction). To prevent the contamination of bio sample, the once used biochip must not be used repeatedly. However, the fabrication cost of microheater and microsensor of the biochip was not cheap to use it as a disposable chip. This paper proposes new PCR-chip where the glass substrate integrated with the microheater and microsensor is detachable from the reaction chamber where the sample is injected. That makes it possible to reuse the glass substrate repeatedly. The performance of the proposed detachable PCR-chip was compared with that of the precedent monolithic PCR-chip. The results showed that the SRY (sex determining Y chromosome) gene PCR was successfully performed in the detachable chip compared with the monolithic chip. However, the more efforts to improve the efficiency of surface treatment of PDMS chip are needed to increase the possibility of applying the detachable chip to the detecting of male infertility.

• KSBB Journal
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• v.21 no.4
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• pp.302-305
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• 2006

In this work, we attempted the application of cell-free protein synthesis technology for the rapid generation of truncated enzymes. Truncated DNAs of a transaminase were PCR-amplified and directly expressed in cell-free protein synthesis reactions. Variants of the transaminase were rapidly prepared and analyzed for their enzymatic activity. Described method that combines the PCR and cell-free protein synthesis technologies will offer a versatile platform for the rapid generation of optimally modified protein species.

• Korean Journal of Veterinary Service
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• v.29 no.1
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• pp.1-8
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• 2006

Porcine circovirus (PCV) is a small, nonenveloped virus that contains a single-stranded circular DNA genome of about 1.76 kb and belongs to the family circoviridae. The PCV-2 has been incriminated as the cause of post-weaning multisystemic wasting syndrome (PMWS) , an emerging disease in pigs. In the present study, a PCR assay was applied to detect PCV-2 in tissue samples. The presence of PCV-2 antigen in the porcine tissues was confirmed by indirect immunofluorescence (IIF) with PCV-2 specific monoclonal antibodies. And then DNA extracted from PCV-2 positive tissues was used as a template. One oligonucleotide primer suitable for PCR was selected from a published PCV-2 sequence (Genbank). Amplified PCR product was detected the same fragment lengths of 416 bp as a control. Based on these results, it was suggested that the PCR is a simple and sensitive method for support diagnostic purposes.

• Korean Journal of Veterinary Service
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• v.38 no.1
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• pp.31-36
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• 2015

Two cats were obtained from a cat kennel. Over the previous 7 days, the cats had shown cough, anorexia, depression and nasal discharge. In this study, the consensus PCR was able to detect successfully Mycoplasma species in nasal swab samples of the cats. To identify feline mycoplasma species from the lung tissue of the cats with pneumonia, Mycoplasma species-specific PCR reactions were conducted. As the results, we could identify M. felis by the positive amplified DNAs. On the other hand, we could not detect any positive reactions with the PCR reaction for M. arginini, M. canis, M. edwardii, M. cynos, M. gateae, M. maculosum, M. molared, M. opalescens, M. spumans and Mycoplasma HRC-689. In conclusion, we detected M. felis from the kenneled cats with pneumonia. We suggested that this consensus PCR would be useful and effective for monitoring Mycoplasma species in various kinds of animals including cats. The application of preceding consensus PCR before the species-specific PCRs may be the most recommended strategy for the identification of Mycoplasma spp.

• The Plant Pathology Journal
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• v.38 no.6
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• pp.616-628
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• 2022

Resistance to pyraclostrobin due to a single nucleotide polymorphism at 143rd amino acid position on the cytochrome b gene has been a major source of concern in red pepper field infected by anthracnose in Korea. Therefore, this study investigated the response of 24 isolates of C. acutatum and C. gloeosporioides isolated from anthracnose infected red pepper fruits using agar dilution method and other molecular techniques such as cytochrome b gene sequencing, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and allele-specific polymerase chain reaction (PCR). The result showed that four isolates were resistant to pyraclostrobin on agar dilution method and possessed GCT (alanine) codon at 143rd amino acid position, whereas the sensitive isolates possessed GGT (glycine). Furthermore, this study illustrated the difference in the cytochrome b gene structure of C. acutatum and C. gloeosporioides. The use of cDNA in this study suggested that the primer Cacytb-P2 can amplify the cytochrome b gene of both C. acutatum and C. gloeosporioides despite the presence of various introns in the cytochrome b gene structure of C. gloeosporioides. The use of allele-specific PCR and PCR-RFLP provided clear difference between the resistant and sensitive isolates. The application of molecular technique in the evaluation of the resistance status of anthracnose pathogen in red pepper provided rapid, reliable, and accurate results that can be helpful in the early adoption of fungicide-resistant management strategies for the strobilurins in the field.

• Microbiology and Biotechnology Letters
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• v.39 no.1
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• pp.70-76
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• 2011

PCR-based Weissella species-specific detection method was developed to apply for the discrimination of Korean and Chinese kimchi by detecting a Weissella species only found in Korean or Chinese kimchi. PCR primers were designed from the species-specific sequence in the recN gene of each species. The primers allowed the species-specific detection and identification of nine species in the genera Weissella, and were successfully applied to the detection of W. cibaria, W. confusa, W. koreensis, and W. soli in kimchi with 20 ng template DNA. W. cibaria, W. confusa, and W. koreensis were detected from the Korean kimchi samples tested but W. soli was not detected. However, the four species were detected from Chinese kimchi samples. PCR-based W. soli-specific detection could not be perfectly applied as the Chinese kimchi discriminating method but has significance as an approach to evaluate the potential of scientific verification method based on the difference of microbial community.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.455-460
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• 2010

A polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis was applied to detect and identify ten Weissella spp. frequently found in kimchi. The previously reported genus-specific primers designed from 16S rDNA sequences of Weissella spp. were adopted but PCR was performed at the increased annealing temperature by $4^{\circ}C$. The sizes of amplified PCR products and restricted fragments produced by AluI, MseI, and BceAI endonucleases were well correspond with the expected sizes. W. kandleri, W. koreensis, W. confusa, W. minor, W. viridescens, W. cibaria, and W. soli were distinguished by AluI and MseI and W. hellenica and W. paramesenteroides were identified by BceAI. W. thailandensis was distinguished when restriction pattern of other species was compared but identified by the single use of MspI.