• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.419-424
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• 1998

An enzyme-linked immunosorbent assay (ELISA) was established for the detection of zearalenone by using monoclonal antibodies produced by Z-M-26 hybridoma cells when injected into a mouse and zearalenone-oxime-OV A conjugate. Zearalenone-oxime-OV A conjugates were diluted with carbonyl buffer, coated to 96 well microtiter plates at $4^{\circ}C$ overnight and blocked with 1% BSA overnight. One thousand times diluted antibody solution together with standard zearalenone or sample was added to 96-well microtiter plates and stood overnight. A secondary antibody conjugated with HRP was added and an hour later, enzyme substrate (TMBZ) solution was added for color develpment. Mter 30 minutes, coloring reaction was terminated by adding 2 N $H_2S0_4$ and the O.D. was measured at 450 nm. Detection range of this method was about 0.1~100 ppb. The established indirect competitive ELISA method was suitable for a rapid and effective analysis of zearalenone in agricultural products.

• 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.

• Clinical and Experimental Reproductive Medicine
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• v.17 no.1
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• pp.71-80
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• 1990

New immunoassay systems for the detection of anti-sperm antibodies were developed. For this, sperm surface protein was purified by the immunoaffinity column prepared by the coupling of rabbit anti-human IgG antibodies to Sepharose-4B. Fraction eluted by tris-HCI buffer containing SDS showed a single band having molecular weight of about 60KD on electrophoresis. Enzyme HRP labelled goat anti-human IgG and chemiluminescence aminobutylethyl-isoluminol(ABEI) labelled rabbit anti-human IgG were used for ELISA and CIA, respectively. These two labelled conjugate bound well with human IgG. When serum dilution curves were made to titrate positive serums, two kinds of curves with steep and sluggish slopes were obtained Serum samples were categorized into 3 groups: positive, weak positive and negative based on slope of curve and O.D. values at 1:160 dilution of serum. When ELISA and CIA were compared to conventional method Kibrick test by the determinations of 62 male serums with different diagnosis, the results of ELISA and CIA agreed well, but both disagreed with that of Kibrick test. This study showed that purified sperm surface antigen can be used to develope solid-phase immunoassay systems such as ELISA and CIA which may eliminate the problems encounted the immobilization of living sperm in other tests.

• Journal of Veterinary Science
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• v.23 no.5
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• pp.32.1-32.11
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• 2022

Background: Classical swine fever (CSF) is a severe infectious disease of pigs that causes significant economic losses to the swine industry. Objectives: This study developed a solid-phase blocking enzyme-linked immunosorbent assay (spbELISA) method for the specific detection of antibodies against the CSF virus (CSFV) in porcine serum samples. Methods: A spbELISA method was developed based on the recombinant E2 expressed in Escherichia coli. The specificity of this established spbELISA method was evaluated using reference serum samples positive for antibodies against other common infectious diseases. The stability and sensitivity were evaluated using an accelerated thermostability test. Results: The spbELISA successfully detected the antibody levels in swine vaccinated with the C-strain of CSFV. In addition, the detection ability of spbELISA for CSFV antibodies was compared with that of other commercial ELISA kits and validated using an indirect immunofluorescence assay. The results suggested that the spbELISA provides an alternative, stable, and rapid serological detection method suitable for the large-scale screening of CSFV serum antibodies. Conclusions: The spbELISA has practical applications in assessing the vaccination status of large pig herds.

• Korean Journal of Veterinary Research
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• v.31 no.4
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• pp.491-500
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• 1991

This study was conducted to detect the serum antibodies in the experimentally toxoplasma infected dogs and street dogs by use the of an enzyme-linked immunosorbent assay (ELISA). And this test was performed on the polystylene microplate by coating with the tachyzoites soluble antigen of T gondii (RH strain), incubated with sera diluted then, added with HPO-conjugated rabbit anti-dog IgG and o-phenylenediamine used as a substrate. Tachyzoites of T gondii harvested from mouse peritoneal cavity were purified by 30, 40 and 50% Percoll density gradient centrifugation and used as the source of antigen. The results obtained were summarized as follows; 1. The highest ratio of positive to negative (P/N ratio) was obtained at the level of $l{\mu}g/ml$ protein concentration of antigen with the 1/4000 dilution of the conjugate measured by checker-board titration. It was regarded as the optimum concentration of the antigen and conjugate. 2. Cut-off value in this IgG ELISA was 0.375 that was determined by mean absorbance (at 492nm) of IFA negative serum added with the dauble value of the standard deviation $(mean{\pm}2S.D.)$. 3. Serum ELISA IgG antibodies to T gondii in the exyerimentally infected dogs were detected firstly at the Week 3 after inoculation and the highest titer was recognized at the Week 4, 5 and 6 after inoculation. 4. Stability of the antigen absorbed in the microplates that were preserved at $4^{\circ}C$ and $-25^{\circ}C$ separately were prolonged up to 3 weeks and 10 weeks at $4^{\circ}C$ and $-25^{\circ}C$, respectively. However the reproducibility was not reliable after the preservation of 4 weeks and longer. 5. Positive rate of the specific antibodies in 312 test sera was 28.5% and there was no significant differences between the male (27.8%) and female (29.5%), respectively. 6. The IgG ELISA was proved to be a specific procedure for the detection of antibodies to canine toxoplasma infection and also evaluated as a screening test for the large scale of test samples in laboratory.

• Korean Journal of Veterinary Service
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• v.37 no.4
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• pp.241-246
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• 2014

Q fever is a zoonotic disease caused by the obligate intracellular bacterium Coxiella (C.) burnetii and affects wild and domestic animals worldwide. The aim of this study was to evaluate the seroprevalence of C. burnetii in native Korean goat (Capra hircus coreanae) in Gyeongbuk province, Korea, using ELISA. A total of 256 goat blood samples from 56 farms in Gyeongbuk province were collected between May 2012 and March 2013. Among them, 22 (8.6%) samples from 10 (17.9%) farms were seropositive for C. burnetii by ELISA. According to regional analysis, the seroprevalences among goat farms in eastern, western, southern, and northern areas of Gyeongbuk province were 0%, 18.2%, 36.8%, and 6.3%, respectively, showing the highest seroprevalence in the southern region. Among 22 counties in Gyeongbuk province, 10 (45.5%) counties had one or more farms positive to C. burnetii antibody. Accordingly, the seroprevalence of C. burnetii in high-risk humans and animals are constantly demanded by regional investigation.

• Korean Journal of Veterinary Research
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• v.29 no.4
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• pp.567-575
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• 1989

This study was conducted to evaluate the possibility of application of a microenzyme-linked immunosorbent assay(micro-ELISA) for the serodiagnosis of specific toxoplasma antibodies in swine sera and this test was performed as a microplate system by coating the polystyrene plates with toxoplasma soluble antigen, incubated serially diluted sera, then added horse radish peroxidase labelled goat anti-swine IgG(r) conjugate followed by o-phenylenediamine as substrate. The color development by enzyme-substrate reaction was determined by the photometric reading [ELISA reader at 490nm (OD)] and visual reading. The soluble antigen was prepared from the tachyzoites in mouse peritoneal cavity. A total of 1,200 swine sera from pig slaughter-house and a total of 116 swine sera from pig breeding station (S-C farm) were tested for the detection of antibodies to Toxoplasma gondii. The results obtained were summarized as follows: 1. The optimal reactions of indirect ELISA for the test sera were determined by the dilution of antigen 1:256 and 1:3,200 of horse radish peroxidase conjugate [anti-swine IgG(r)]. 2. The specific togoplasma antibody(IgG) in pigs infected with Tp artificially were detected as the serum titers of 1:64 or 1:128 at one week postinfection. 3. Of a total of 1,200 swine sera from pig slaughter-house 505 samples of sera were detected as positive (42.1%) and of a total of 116 swine sera from S-C pig breeding station 68 samples of sera as positive (58.6%). 4. The specific antibody(IgG) detection rates against a total of 1,200 test sera from pig slaughter-house were not significant between male (43.1%) and female (40.7%). 5. The indirect ELISA was proved to be a sensitive and specific procedure for the serodiagnosis of swine toxoplasmosis and also evaluated as an effective screening test for the large scale of test samples in laboratory.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.41-46
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• 2014

The mature domain of a cysteine protease of Spirometra erinacei plerocercoid larva (i.e., sparganum) was expressed in Escherichia coli, and its value as an antigen for the serodiagnosis of sparganosis was investigated. The recombinant protein (rSepCp-1) has the molecular weight of 23.4 kDa, and strongly reacted with the sparganum positive human or mice sera but not with negative sera by immunoblotting. ELISA with rSepCp-1 protein or sparganum crude antigen (SeC) was evaluated for the serodiagnosis of sparganosis using patient's sera. The sensitivity and specificity of ELISA using rSepCp-1 protein were 95.0% (19/20) and 99.1% (111/112), respectively. In contrast, the sensitivity and specificity of ELISA with SeC were 100% (20/20) and 96.4% (108/112), respectively. Moreover, in experimentally infected mice, the sensitivity and specificity of both ELISA assays were 100% for the detection of anti-sparganum IgG. It is suggested that the rSepCp-1 protein-based ELISA could provide a highly sensitive and specific assay for the diagnosis of sparganosis.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.22-25
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• 1998

These studies were conducted to develope analysis method of herbicide quizalofop-ethyl by Gas Liquid Chromatography(GLC) and Enzyme-Linked Immunosoment Assay(ELISA) in soil and plant. Quizalofop produced by hydrolysis of quizalofop-ethyl was conjugated with bovine serum albumin(BSA). Quizalofop antibody was developed in rabbits by using BSA conjugation. Antibody titer, incubation temperature, and incubation time was 32,000, $37^{\circ}C$ and 4hours respectively. Minimum detection limit of quizalofop-ethyl by ELISA was 5ppb. Quizalofop-ethyl recovery from soil by ELISA was more than 95percent. Minimum detection limit of quizalofop-ethyl by GLC was 5ppb. Quizalofop-ethyl recovery from soil by GLC was from 89 percent to 100 percent. Minimun detection limit of quizalofop-ethyl by HPLC was 100ppb. Quizalofop-ethyl recovery from soil by HPLC was 89.6 percent.

• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.377-392
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• 1987

Monoclonal antibody to the Escherichia coli heat-stable enterotoxin(ST) was produced to develop a rapid and convenient diagnostic method to the ST. The toxin was purified from culture supernatant of enterotoxigenic E. coli O148H28($ST^+/LT^+$) and conjugated to bovine serum albumin(BSA). The ST-BSA conjugate was used to immunize BALB/c mice and the immune spleen cells from these mice were fused with $P3{\times}63$ Ag8.V653 plasmacytoma cells. Hybridomas were screened by ELISA and positive hybridomas were cloned by limiting dilution. Finally, one stable clone (AS36) specific to ST was selected for further growth and characterization. Antibody titers of culture supernatant and ascitic fluid from BALB/c mice were 1:1,024 and 1:20,480 respectively in ELISA. The isotype and subclass of monoclonal antibody was IgG1 in sandwich ELISA. To test the neutralizing effect of monoclonal antibody on toxin activity of ST, mixture of ascitic fluid and ST was assayed by infant mouse assay and this monoclonel antibody was proved to be a neutralizing antibody. The titer of ascitic fluid which completely neutralized biological activity of 4 units of ST was 1:4. Purified ST was quantitatively measured by competitive ELISA and minimum amount of ST detectable by this assay was 250pg, which was an amount six-fold smaller than that detectable by infant mouse assay. Four reference strains of enterotoxigenic E. coli from WHO were detected by competitive ELISA and highly specific, sensitive and reproducible result was obtained.