• Journal of Microbiology
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• 제45권4호
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• pp.297-304
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• 2007

The detection of virulence factors of Aeromonas is a key component in determining potential pathogenicity because these factors act multifunctionally and multifactorially. In this study water samples were collected from a trout farm on a seasonal basis, and diseased fish and Aeromonas species were isolated and identified. For rapid detection of six virulence factors of isolated Aeromonas, a hexaplex-polymerase chain reaction (hexaplex-PCR) assay was used. The detected virulence factors include aerolysin (aer), GCAT (gcat), serine protease (ser), nuclease (nuc) lipase (lip) and lateral flagella (laf). The dominant strain found in our isolates was Aeromonas sobria, and the dominant virulence factors were aer and nuc for all seasons. We confirmed that A. sobria and two of the virulence genes (aer and nuc) are related. We proposed a method by which one can identify the major strains of Aeromonas: A. hydrophila, A. sobria, A. caviae, and A. veronii, using hexaplex-PCR.

• Applied Science and Convergence Technology
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• 제25권3호
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• pp.61-65
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• 2016

Here, the rapid detection of Salmonella typhimurium by a portable surface plasmon resonance (SPR) biosensor in which the beam from a diode laser is modulated by a rotating mirror is reported. Using this system, immunoassay based on lipopolysaccharides (LPS)-specific monoclonal anti-Salmonella antibody was performed. For the purpose of orientation-controlled immobilization of antibodies on the SPR chip surface, the cysteine-mediated immobilization method, which is based on interaction between a gold surface and a thiol group (-SH) of cysteine, was adopted. As a result, using the portable SPR-based immunoassay, we detected S. typhimurium in the range from 10^7 CFU/mL to 10^9 CFU/mL within 1 hour. The results indicate that the portable SPR system could be potentially applied for general laboratory detection as well as on-site monitoring of foodborne, clinical, and environmental agents of interest.

• Journal of Microbiology and Biotechnology
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• 제21권1호
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• pp.100-108
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• 2011

A method for the rapid detection and quantification of Newcastle disease virus (NDV) produced in an animal cell culture-based production system was developed to enhance the speed of the NDV vaccine manufacturing process. A SYBR Green I-based real-time RT-PCR was designed with a conventional, inexpensive RT-PCR kit targeting the F gene of the NDV LaSota strain. The method developed in this study was validated for specificity, accuracy, precision, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The validation results satisfied the predetermined acceptance criteria. The validated method was used to quantify virus samples produced in an animal cell culture-based production system. The method was able to quantify the NDV samples from mid- or late-production phases, but not effective on samples from the early-production phase. For comparison with other quantifiable methods, immunoblotting, plaque assay, and tissue culture infectious dose 50 ($TCID_{50}$) assay were also performed with the NDV samples. The results demonstrated that the real-time RT-PCR method is suitable for the rapid quantification of virus particles produced in an animal cell-culture-based production system irrespective of viral infectivity.

• Fisheries and Aquatic Sciences
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• 제11권4호
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• pp.205-208
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• 2008

The mixotrophic dinoflagellate Cochlodinium polykrikoides was reported to be linked to major fish kills in Korea and Japan since the 1990s. Rapid and sensitive detection of microalgae has been problematic because morphological identification of dinoflagellates requires light microscopic and scanning electron microscopic observations that are time consuming and laborious compared to real-time PCR. To address this issue, a real-time PCR probe targeting the ITS2 rRNA gene was used for rapid detection and quantification of C. polykrikoides. PCR inhibitors in water column samples were removed by dilution of template DNA for elimination of false-negative reactions. A strong association between cell quantification using real-time PCR and microscopic counts suggests that the real-time PCR assay is an alternative method for cell estimation of C. polykrikoides in environment samples.

• 한국식품위생안전성학회지
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• 제38권5호
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• pp.279-286
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• 2023

Rapid and accurate detection of pathogenic bacteria is crucial for various applications, including public health and food safety. However, existing bacteria detection techniques have several drawbacks as they are inconvenient and require time-consuming procedures and complex machinery. Recently, the precision and versatility of CRISPR/Cas system has been leveraged to design biosensors that offer a more efficient and accurate approach to bacterial detection compared to the existing techniques. Significant research has been focused on developing biosensors based on the CRISPR/Cas system which has shown promise in efficiently detecting pathogenic bacteria or virus. In this review, we present a biosensor based on the CRISPR/Cas system that has been specifically developed to overcome these limitations and detect different pathogenic bacteria effectively including Vibrio parahaemolyticus, Salmonella, E. coli O157:H7, and Listeria monocytogenes. This biosensor takes advantage of the CRISPR/Cas system's precision and versatility for more efficiently accurately detecting bacteria compared to the previous techniques. The biosensor has potential to enhance public health and ensure food safety as the biosensor's design can revolutionize method of detecting pathogenic bacteria. It provides a rapid and reliable method for identifying harmful bacteria and it can aid in early intervention and preventive measures, mitigating the risk of bacterial outbreaks and their associated consequences. Further research and development in this area will lead to development of even more advanced biosensors capable of detecting an even broader range of bacterial pathogens, thereby significantly benefiting various industries and helping in safeguard human health

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2003년도 하계 학술대회 논문집
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• pp.421-426
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• 2003

The Immunosensor based on antigen-antibody binding have been developed for detecting several analytes including antigen, small molecules, and cell. This method can be rapid and show very good detection limits. For Implementation of immunosensor, technologies for immobilization of antibody onto solid surface and detection of protein-protein binding must be developed. (an ellipsis)

• 전력전자학회논문지
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• 제27권2호
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• pp.100-105
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• 2022

This paper applies the arc detection algorithm to prevent the false detection in photo voltaic series arc detection circuit, which is required not only to detect the series arc quickly, but also not falsely detect the arc for the non-arc noise. For this purpose, this study proposes a rapid and preventive false detection method of single peak noise and short noise signals. First, to prevent false detection by single peak noise, Discrete wavelet transform (DWT)-based characteristic parameters are applied to determine the shape and the amplitude of the noise. In addition, arc fault detection within a few milliseconds is performed with the DWT iterative algorithm to quickly prevent false detection for short noise signals, considering the continuity of serial arc noise. Thus, the method operates not only to detect series arc, but also to avoid false arc detection for peak and short noises. The proposed algorithm is applied to real-time serial arc detection circuit based on the TMS320F28335 DSP. The serial arc detection and peak noise filtering performances are verified in the built simulated arc test facility. Furthermore, the filtering performance of short noise generated through DC switch operation is confirmed.

• 한국양봉학회지
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• 제34권1호
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• pp.39-46
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• 2019

BQCV multi-point PCR was developed as a rapid multiplex detection method for BQCV, one of the viral pathogens of honeybees. It could detect BQCV specific genes qualitative as well as quantitative detection based on ultra-rapid PCR. Three primer pairs (RNA dependent RNA polymerase, capsid protein, 3C like protease) were specifically designed for accurate the detection and were optimized for minimizing the detection time and increasing the sensitivity. Our advanced diagnostic system have the accuracy by lowering the concern about the variation in the BQCV detection site. In addition, it should be an opportunity to identify mutations that are mixed with other viruses.

• 한국식품과학회지
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• 제52권3호
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• pp.296-303
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• 2020

Hop-resistant lactic acid bacteria (LAB) are well-known, major beer-spoilage bacteria. The hop-gradient agar containing ethanol (c-HGA+E) method has been used to examine hop-resistance of beer-spoilage LAB. However, the selection of beer-spoilage bacteria by the c-HGA+E method is either too selective or too inclusive. Furthermore, it is accompanied by a complicated experimental procedure, high-cost and time. To overcome these disadvantages, the modified hop-gradient agar with ethanol (m-HGA+E) method was developed. The most remarkable modifications were the shape of the petri dish and the inoculation method for bacteria. The efficiency and validation of the m-HGA+E approach were proven by the formation of colonies at different hop concentrations in the bottom layer, co-culture with the bacteriocin producer and by PCR detection of hop-resistant genes. This study demonstrated that m-HGA+E is a rapid, economical, and easy method to monitor potential hop-resistant beer-spoilage LAB during the beer brewing process.

• 센서학회지
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• 제22권5호
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• pp.346-351
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• 2013

We developed a one-step method for fabrication of addressable suspended SWNT films and demonstrate excellent detection performance of paraoxon based on OPH-immobilized SWNT films for environmental monitoring. For dispersed SWNT suspension, COOH-SWNT was prepared by the oxidation of carbon nanotubes using acid treatment and sonication. Suspended SWNT-film was fabricated between cantilever electrodes by dielectrophoretic force and surface tension of the water meniscus. After that, OPH were immobilized on suspended SWNT-films by nonspecific binding for enzymatic hydrolysis of paraoxon. The electrical properties of the SWNT films were measured in real time at room temperature. Structurally suspended SWNT films from substrate surface made possible rapid and highly sensitive detection of target molecules with increased convectional and diffusional fluxes of the molecules and with a large binding surface area. SWNT film FET resulted in a real-time, label-free, and electrical detection of paraoxon to the concentration of ca. $10{\mu}m$ with a step-wise rapid response time of several seconds.