• Food Science and Preservation
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• v.30 no.2
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• pp.262-271
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• 2023

The objective of this study is to compare and assess the effectiveness of real-time polymerase chain reaction (RT-PCR), loop-mediated isothermal amplification (LAMP), and the selective agar plate method for the detection of Salmonella spp. and Listeria monocytogenes in ready-to-eat (RTE) foods. In RTE foods, the detection performance of the three methods (RT-PCR [SureTect^TM kit and PowerChek^TM kit], LAMP [3M MDS], selective agar) were similar at 0-10, 10-50, 50-100, and 100- CFU/mL of Salmonella spp. and L. monocytogenes. We found that with RT-PCR, the Ct value of salad was significantly higher (p<0.05) than other RTE foods, indicating that fiber plays a critical role as an obstacle to the rapid detection of Salmonella spp. However, the Ct value displayed a mixed pattern according to the inoculation level of L. monocytogenes. The use of rapid detection kits and machines mostly depends on the user's choice, with accuracy, ease of use, and economy being the primary considerations. As an RT-PCR kit, SureTect^TM and PowerChek^TM showed high accuracy in detecting Salmonella spp. and L. monocytogenes in RTE foods, showing that they can replace the existing RT-PCR kits available. Additionally, LAMP also showed excellent detection performance, suggesting that it has the potential to be used as a food safety management tool.

• Journal of Biosystems Engineering
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• v.36 no.2
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• pp.140-146
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• 2011

This study was performed to develop a rapid test kit for pathogenic Salmonella in various samples. The rapid detection kit has been fabricated based on nitrocellulose lateral-flow strip. Colloidal gold and biotin conjugated Salmonella antibodies were used as a tag and a receptor, respectively. Manually spotted Salmonella antibody and Neutravidin on nitrocellulose membrane were used as test and control lines, respectively. Feasibility of the rapid kit to detect Salmonella typhimurium in samples were evaluated. The intensity of the color of the test line started to increase with the samples in which higher concentration of the cells were contained. The sensitivity of the sensor was $10^6$ cfu/mL Salmonella spiked in PBS. Also, the rapid test kit could detect $10^6$ cfu/mL of Salmonella in chicken meat extract.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.139-146
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• 2013

This study was performed to develop a rapid test kit for pathogenic Staphylococcus in various samples. The rapid detection kit has been fabricated based on nitrocellulose lateral-flow strip. Colloidal gold and Staphylococcus antibodies were used as a tag and a receptor, respectively. Manually spotted Staphylococcus antibody and anti-mouse antibody on the surface of nitrocellulose membrane were used as test and control lines, respectively. Feasibility of the rapid kit to detect Staphylococcus aureus in samples were evaluated. The intensity of the color of the test line started to increase with the samples in which higher concentration of the cells were contained. The sensitivity of the sensor was $10^6$ cfu/mL Staphylococcus spiked in PBS. Also, the rapid test kit could detect $10^5$ cfu/mL of Staphylococcus in chicken meat extract.

• KSBB Journal
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• v.31 no.1
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• pp.46-51
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• 2016

Recently paper based diagnostic kits have drawn great interest in the point-of-care testing market (POCT). The paper based detection systems provide inexpensive, rapid and safe analyses for disease markers and/or pathogens. Vitamin C (i.e., ascorbic acid) regulates body's immune system as an antioxidant agent. Humans, however, do not have enough amounts of enzymes involved in the synthesis of vitamin C that it is required to be obtained from their diets (e.g., beverages and/or supplements). Here, we have prepared a paper based kit to detect the concentration of Vitamin C presented in commercially available beverages. The evaluation provides the fast, simple and accurate results for detecting Vitamin C in the prepared paper based kit.

• Research in Plant Disease
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• v.20 no.1
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• pp.15-20
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• 2014

A rapid, user-friendly and simple immune-chromatographic dipstick kit named 'rapid immune-gold strip' (RIGS) kit was developed in a novel single strip format to detect on-site detection of Tomato spotted wilt virus (TSWV). Immunoglobulin G (IgG) from polyclonal antisera raised in rabbits against TSWV was purified through protein-A affinity chromatography and then the purified TSWV-IgG was conjugated to colloidal gold nano-particles which served as a test line on nitrocellulose membrane. Protein A that non-specifically binds to TSWV antibody was used as a control line on the same strip. The diagnosis process with the TSWV-RIGS involves simply grinding the suspect plant sample in a bag that contains the extraction buffer and inserting the strip the bag. Results can be seen in 2-5 minutes. The flow of the complexes of gold particles coated with TSWV-IgG and a crude sap from TSWV-infected pepper, tobacco and tomato plants resulted in intensive color formed on the test lines proportional to the concentrations of TSWV. The RIGS-TSWV kit did not show any cross-reactions against other tomato-infecting viruses unrelated to TSWV. These results indicate that the TSWV-RIGS kit is highly sensitive and is not required for laboratory training and experience prior to testing. The TSWV-RIGS kit is suitable for on-site detection of suspect TSWV-infected plants as well as for laboratory diagnosis.

• Journal of Food Hygiene and Safety
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• v.36 no.1
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• pp.93-99
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• 2021

This study was undertaken to compare the efficacy of different sample preparation (stomaching, pulsifying, and sonication) and DNA extraction methods (boiling and commercial kit) for detection of enterotoxin-producing Clostridium perfringens from produce by polymerase chain reaction (PCR). Each produce type was inoculated at concentrations of 102, 103, 104, 105, 106, and 107 spores/g. Produce inoculated with spores was treated with three sample preparation methods, and DNA was extracted by boiling method and a commercial kit, followed by PCR. The detection limit of stomached samples was lower than that of pummeled and sonicated samples by 10-100 times. Moreover, the DNA extraction efficiency of the commercial kit was found to be superior to that of boiling. In particular, the PCR efficiency of cherry tomato and perilla leaf samples was greatly affected by sample preparation and DNA extraction method. These data suggest that DNA extraction with a commercial kit after pulsification is an optimum sample preparation method for detection of C. perfringens by PCR.

• Biomolecules & Therapeutics
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• v.10 no.3
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• pp.186-192
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• 2002

Special attention has been paid to human chorionic gonadotropin (hCG) for athlete doping control because it stimulates the endogenous production of testosterone and epitestosterone without increasing the T/E ratio which is a doping indicator for the exogenous administration of testosterone. Even though the IOC banned the use of hCG, a detection method has not been decided upon since there are a variety of immunoassay kits available on the market. We evaluated three kits in terms of their performance characteristics. The assay value of the control sample varied depending on the kit, resulting in 198 mIU/ml for the MAIA kit, 172mIU/ml for the IRMA kit, and 143 mIU/ml for the MEIA kit. Considering the IOC inter-lab distribution of results(55-312 mIU/ml) using 27 different kits and the mean value (178$\pm$56 mIU/ml), all three kits are within the range of －15.8% - ＋5.6% of the mean value, which proves them useful for the hCG assay. The MEIA kit resulted in lower hCG values because it detects only intact hCG molecules, in contrast to the other two kits which detect intact hCG and -hCG together. However, it is suitable for screening purposes because of its advantage of being an automated system. When 123 urine samples of athletes were analyzed in 22 batches using this system, the variation of control values fell within $\pm$ 10% of the mean values, and an specimens tested negative with hCG values less than the detection limit of 2 mIU/ml.

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.335-340
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• 2016

This study was conducted to find out the most suitable DNA isolation methods for PCR detection of foodborne pathogens. Four DNA isolation methods including Universal Genomic DNA Extraction Kit (TaKaRa), PrepMan Ultra (Applied Biosystems), boiling method and alkaline lysis method (w/PEG) were tested and compared. The Universal Genomic DNA Extraction kit (TaKaRa) was considered as the more efficient isolation method for Escherichia coli O157:H7 and Staphylococcus aureus in lettuce, fish and beef. Meanwhile to detect the foodborne pathogens directly from foods without enrichment, the four different buffers such as double-distilled water, saline, glycine-saline, glycine-saline with Tween-20 and beef extract were also evaluated. As a result, saline was more suitable buffer for E. coli O157:H7. And double-distilled water was more suitable buffer than saline for S. aureus, respectively

• Food Science of Animal Resources
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• v.33 no.2
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• pp.198-204
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• 2013

This study aimed to apply the Parallux system to detect (fluoro)quinone antibiotics residues in raw bovine milk. The immunogen enabled the generation of a specific antiserum with a titer of 1/40,000. The $Parallax^{TM}$ kit using the antibody displayed $IC_{50}$ value of 10 to 150 ppb for (fluoro)quinolone antibiotics. $Parallax^{TM}$ kit was also sensitive for the detection of incurred (fluoro)quinolone at Korean Maximum Residual Levels in raw bovine milk as the result of dose response test. Cross reactivities of the antibody with the common (fluoro)quinolones were determined to be norfloxacin, 100%; enrofloxacin, 100%; ciprofloxacin, 100%; danofloxacin, 100%; nalidixic acid, 40%. Lower detection limit (LOD) values of the $Parallax^{TM}$ kit in raw bovine milk were determined to be norfloxacin, 4 ppb; enrofloxacin, 5 ppb; danofloxacin, 5 ppb; ciprofloxacin, 5 ppb and nalidixic acid, 10 ppb. The $Parallax^{TM}$ kit was run 8 times with five different concentrations of norfloxacin to determine the coefficient of variation (CV, %) of intra-assay, which was between 2.7% and 11.8%. To confirm the precision among kit batches for the inter-assay, five different batch kits were tested with 2 different concentration of norfloxacin. The CVs of the inter assay were 4.2% at 50 ppb, and 7.2% at 10 ppb norfloxacin, respectively.

• Journal of Veterinary Science
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• v.23 no.4
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• pp.51.1-51.10
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• 2022

Background: Due to the unavailability of an effective vaccine or antiviral drug against the African swine fever virus (ASFV), rapid diagnosis methods are needed to prevent highly contagious African swine fever. Objectives: The objective of this study was to establish the ladder-shape melting temperature isothermal amplification (LMTIA) assay for the detection of ASFV. Methods: LMTIA primers were designed with the p72 gene of ASFV as the target, and plasmid pUC57 was used to clone the gene. The LMTIA reaction system was optimized with the plasmid as the positive control, and the performance of the LMTIA assay was compared with that of the commercial real-time polymerase chain reaction (PCR) kit in terms of sensitivity and detection rate using 200 serum samples. Results: Our results showed that the LMTIA assay could detect the 10⁴ dilution of DNA extracted from the positive reference serum sample, which was the same as that of the commercial real-time PCR kit. The coincidence rate between the two assays was 100%. Conclusions: The LMTIA assay had high sensitivity, good detection, and simple operation. Thus, it is suitable for facilitating preliminary and cost-effective surveillance for the prevention and control of ASFV.