• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.119-125
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• 1996

In order to develop enzyme-linked immunosorbent assay (ELISA) for fumonisins, production of specific antibodies, establishment of ELISA conditions, and quantitation of the toxin from spiked corns by ELISA were performed. Fumonisin $B_1(FB_1)$ conjugated to cholera toxin (CT) with or without Freund's adjuvant was subcutaneously injected into 2 groups of rabbits. When the titer of the antisera produced by each rabbit was tested, higher titer was observed in case of the immunization with the adjuvant. By use of the antiserum showing the highest titer (1:16,000) and its purified antibodies, competitive indirect and direct ELISA's (ciELISA and cdELISA) were established, respectively. When the cross-reactivity of the antibody against fumonisin analogs was investigated by the ciELISA, it was very low against $B_3$ (2%) but high against fumonisin $B_2$ (179%). The sensitivity of the ELISAs was also very high, because the detection limit for $FB_1$ was 0.03 ppb in ciELISA and 0.3 ppb in cdELISA. When the ELISA's were applied to the spiked corns after extraction with 75% methanol, the assay recovery of $FB_1$ was too unstable to assay. However, when cleanup by strong anion exchange (SAX) cartridge was introduced to remove interfering materials, the mean ELISA recovery of $FB_1$ from corns spiked to 3~10 ppm was found to be 34.0% and stable (mean of CV, 8.2%).

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.564-569
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• 2000

An enzyme-linked immunosorbent assay(ELISA) was developed for the detection of milk proteins in processed foods. The ${\alpha}_{s1}-casein({\alpha}_{s1}-CN)$, a heat stable major milk protein, was immunized into rabbits to produce specific antibodies. When competitive indirect ELISA(ciELISA) using $anti-{\alpha}_{s1}-CN$ antibodies was established, its detection limit was $0.1\;{\mu}g/mL$. The reactivities of the specific antibodies toward ${\alpha}_{s1}-CN$, skim milk, ${\beta}-CN$ and whey protein isolate(WPI) were 100, 37, 0.14 and 0.04%, respectively, as determined by ciELISA. However $anti-{\alpha}_{s1}-CN$ antibodies did not have any reactivity to other milk proteins such as ${\beta}-lactoglobulin,\;{\alpha}-lactalbumin$, bovine serum albumin, and isolated soy protein. When sandwich ELISA was established, its detection limit was $0.01\;{\mu}g/mL$ which was 10 times more sensitive than that of ciELISA. In the spike test which was performed by adding 1-10% of whole CN to market milk, mean assay recovery as determined by sandwich ELISA was 94.8%(CV, 8.2%). Food stuffs and dairy products were assayed by sandwich ELISA to show 29, 0.13, 0.25, and 6.9% of whole CN in skim milk powder, WPI, semi-solid yoghurt, and processed cheese, respectively.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.991-996
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• 2000

Enzyme-linked immunosorbent assay was developed for the analysis of soy protein in foods. Competitive indirect ELISA (ciELISA) was established by using specific antibodies against the heat-stable acidic subunits (AS) of glycinin. Soy proteins in each sample used in this study were solublized in the presence of urea and DTT and boiled at $100^{\circ}C$ for 1hr and then were renatured with a cystine-containing solution. After these treatments, each isolated soy protein (ISP) heated at 60, 70, 80, $90^{\circ}C$ for 10 minutes showed almost the same curve as unheated one in the ciELISA. The detection limit of ISP was 0.3 ${\mu}g/mL$. Anti-AS antibodies have very low reactivities less than 0.1% toward non-meat proteins such as skim milk and casein and did not show any reactivities toward egg white powder and ovalbumin. When laboratory-made sausages containing ISP of $0.5{\sim}3%$ were assayed by ciELISA, the mean recovery was about 83% (C.V., 19%). In addition, the average content of soy protein in commercial sausages was 1.27%.

• The Plant Pathology Journal
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• v.36 no.5
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• pp.509-514
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• 2020

Satsuma dwarf virus (SDV) seriously damages citrus production by reducing the quality and yield of fruit. To avoid contamination with SDV, mother trees are checked to be SDV-free in advance of nursery tree distribution. In this study, we compared an immunochromatographic assay (ICA) kit with double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) for large-scale diagnosis of SDV in orchardgrown trees in Shizuoka Prefecture, Japan. The two methods gave conflicting results for 11 of 1,705 samples, all of which were negative by DAS-ELISA but positive by ICA. The samples scored as positive by either DAS-ELISA or ICA were analyzed by reverse transcription polymerase chain reaction and all were confirmed to be positive. These results validate the use of ICA as a screening method for large-scale diagnosis. Strain discrimination revealed that 16 of 22 isolates belonged to SDV, while citrus mosaic virus (CiMV) infection only and co-infection (SDV and CiMV) were in a minority.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.538-543
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• 2000

This study was conducted to develop an enzyme-linked immunosorbent assay(ELISA) for the determination of cooked goat meat. Muscle proteins were extracted from goat meat by heating at $98^{\circ}C$ for 15 min. Major thermostable(TS) protein, whose size and pI are 36 and 38 kDa and 4.5 respectively, were purified by DEAE-Sephadex A-50 and Sephadex G-75 column chromatography. The TS protein was immunized into rabbits in order to produce goat specific antibodies. Competitive indirect ELISA(ciELISA) was established by using the anti-TS antibody. The antibody showed high reactivity toward the TS antigen and the boiled goat meat extract but it did not show any reactivities toward extracts of boiled chicken, pork, lamb, and beef. Thus, this ciELISA developed in this study could be applicable to identify goat species from cooked meat.

• Journal of Life Science
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• v.20 no.5
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• pp.697-702
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• 2010

Ten farrow-finish farms participated in this seromonitoring that was conducted to investigate the porcine brucellosis situation in Korea. In total, eight (80.0%) of the 10 farms and 139 (24.0%) of 578 pigs tested showed a positive response in the Rose Bengal test (RBT). Seroprevalence levels were determined using RBT according to age; 35 (14.6%) of 239 piglets, 36 (31.3%) of 115 growing pigs, and 68 (30.4%) of 224 finishing pigs and sows were positive, respectively. All positive samples in RBT were tested with the tube agglutination test (TAT) and competitive ELISA (C-ELISA), simultaneously. Although 48 samples came up positive in the TAT, all samples tested with C-ELISA were negative. Among 26 rectal swab samples from the TAT positive-pigs, Yersinia enterocolitica O:9 was isolated from seven samples (26.9%). Therefore, we speculated that the positive reaction of RBT and TAT in this study might be induced by the serologically cross-reacting bacteria with Brucella abortus.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.681-684
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• 2007

An immunoassay method was developed to quantitatively detect phosphinothricin-N-acetyltransferase (PAT) encoded by the Bialaphos resistance (bar) gene in genetically modified (GM) pepper. The histidine-tagged PAT was overexpressed in Escherichia coli M15 (pQE3l-bar) and efficiently purified by $Ni^{2+}$ affinity chromatography. A developed sandwich enzyme-linked immunosorbent assay (S-ELISA) method (detection limit: $0.01{\mu}g/ml$) was 100-fold more sensitive than a competitive indirect ELISA (CI-ELISA) method or Western blot analysis in detecting the recombinant PAT. In real sample tests, PAT in genetically modified herbicide-tolerant (GMHT) peppers was successfully quantified [$4.9{\pm}0.4{\mu}g/g$ of sample (n=6)] by the S-ELISA method. The S-ELISA method developed here could be applied to other GMHT crops and vegetables producing PAT.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.669-676
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• 2004

To evaluate the diagnostic accuracy of two commercial ELISA tests (Allied- and CSL-ELISA) for the diagnosis of Mycobacterium paratuberculosis in cattle, Meta-analysis using English language papers published during 1990-2001 was performed. Diagnostic odds ratios (DOR) were analyzed using regression analysis together with summary receiver operating characteristic (ROC) curves. The difference in diagnostic performance between the two ELISA systems was evaluated by using linear regression. Publication bias was assessed by funnel plot and linear regression. The pooled sensitivity and specificity were 44% (95% CI, 38 to 51) and 98% (95% CI, 96 to 99) for the random-effect model. The DOR between studies was heterogeneous. The area under the fitted ROC curve (AUC) was 0.72 for the unweighted and 0.77 for the weighted model. Maximum joint sensitivity and specificity for the unweighted and weighted model from their summary ROC curve were 70% and 75%, respectively. Based on the fitted model, at a specificity of 95%, sensitivity was estimated to be 52% for the unweighted and 57% for the weighted model. From the final multivariable model study characteristic, the country was the only significant variable with an explained component variance of 13.3%. There were no significant differences in discriminatory power, sensitivity, and specificity between the two ELISA tests. The overall diagnostic accuracy of two commercial ELISA tests was moderate, as judged by the AUC, maximum joint sensitivity and specificity, and estimates from the fitted model and clinical usefulness of the tests for screening program is limited because of low sensitivity and heterogeneous of DOR. It is, therefore, recommended to use ELISA tests as a parallel testing with other diagnostic tests together to increase test sensitivity in the screening program.

• The Korean Journal of Food And Nutrition
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• v.19 no.3
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• pp.296-300
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• 2006

Immunoblotting and competitive indirect enzyme-liked immunosorbent assay(Ci-ELISA) was used for detection of ${\beta}$-lactoglobulin(BLG) in dairy products, such as milk, dried milk and fermented milk. In immunoblotting, human IgE weakly recognized proteins of fermented milk, but still responded to dried milk even though become weak. Rabbit polyclonal antibody to BLG, used as a model of antigen, and milk allergic patients' IgE was used in the ELISA. Reactivities of Abs were the highest in market milk. BLG in fermented milk was detected in a low content. This result indicates the fermented milk have the lowest BLG content and could be used as hypo-allergenic food for milk-allergic individual.

• Korean Journal of Veterinary Service
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• v.43 no.3
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• pp.197-200
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• 2020

This study was performed to determine the seroprevalence of reticuloendotheliosis virus (REV) infection in layer chickens in Gyeonggi province, South Korea. Serum samples were collected from 820 layer chickens on 56 flocks in Gyeonggi province. The samples were tested for specific antibodies against REV using commercial enzyme-linked immunosorbent assay (ELISA). The seroprevalence of REV antibodies in the flocks was 62.50% (95% Confidence interval (CI) 49.33~74.40) and the overall seroprevalence in individual chickens was 39.27% (95% CI 35.97~42.65). The results of the present survey indicate that REV infection is prevalent in layer chickens in Gyeonggi province, South Korea. Therefore, effective measures should be taken to prevent and control REV of layer chickens in this province.