• 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%.

• Biomedical Science Letters
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• v.1 no.1
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• pp.1-8
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• 1995

The present study was undertaken to determine the dissociation constant (Kd)of monoclonal antibody to human apolipoprotein A-I (apo A-I) using enzyme-linked immunosorbent assay (ELISA). First the monoclonal antibody was incubated in solution with the antigen until the equilibrium was reached; then the free antibody which remains unsaturated at equilibrium was captured by binding to antigen on the microtiter plate and be measured by a classical indirect ELISA. The value of Kd determined from Scatchard plot was 0.625$\times$10^{-9}$ for purified antibody and 0.720$\times$10$^{-9}$ for unpurified antibody. This method was valuable for the measurement of true dissociation constant and found to be simple, reproducible, and accurate.

• Parasites, Hosts and Diseases
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• v.47 no.2
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• pp.153-157
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• 2009

Diagnosis of hydatidosis is based on immunodiagnostic methods along with radiological and ultrasound examinations. The objectives of the present study were to develop a specific and simple antigen-based ELISA method for diagnosis of hydatidosis and compare it with antibody detection method. The subjects in this study included 89 patients in the following groups: surgically confirmed hydatidosis patients (35 cases), control with other parasitic diseases (29 cases), and healthy controls (25 cases). Hyperimmune serum was raised against hydatid cyst fluid in rabbits. Anti-hydatid cyst IgG was purified by affinity chromatography using protein A column and labeled with horseradish peroxidase. Collected sera were assessed for hydatid cyst antigens and antibody by ELISA. Circulating hydatid antigen was found in 9 out of 35 patients with surgically confirmed hydatidosis. A sensitivity of 25.7% and a specificity of 98.0% were calculated for the antigen detection assay. Antibody detection by indirect ELISA, using antigen B, showed that 94.2% of patients (33 cases) have anti-hydatid cyst antibodies in their serum while cross reaction was noted in a few of non-hydatidosis patients. A sensitivity of 94.2% and specificity of 81.6% were found for the antibody detection assay. Findings of this study indicated that antibody detection assay is a sensitive approach for diagnosis of hydatid cyst while antigen detection assay might be a useful approach for assessment of the efficacy of treatment especially after removal of the cyst.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.168-173
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• 1988

Immunological analysis between endotoxin proteins produced by Bacillus thuringiensis serovar. kurstaki HD1 and HD73 have been investigated by using polyclonal antibodies. The antisera against the endotoxin proteins were prepared from rabbits injected with the endotoxin protein antigens. When about 2mg/$m\ell$ of the antigens were injected for 7 times, the titers were highest. The stability of the antigens was reduced to about 50% after 9 days incubation at 4$^{\circ}C$. The sensitibity of endotoxin protein from B. thuringiensis HD1 and HD73 by indirect ELISA was 50ng/$m\ell$ and 400ng/$m\ell$, respectively. The cross reaction of antiserum appeared that anti-HD1 partialy reacted with crystal protein but anti-HD73 reacted with HD1 endotoxin about 100%.

• Korean Journal of Veterinary Service
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• v.35 no.2
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• pp.133-137
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• 2012

Brucellosis, a bacterial zoonoses caused by the genus Brucella is responsible for abortion and infertility in cow. Brucellosis is causing economic loss in dairy industries and prevalent worldwide including Bangladesh but limited studies are devoted to determine the prevalence and its association with reproductive factors of dairy cows in Bangladesh. Therefore, the present study was conducted to determine the seroprevalence of brucellosis in dairy cattle using screening test Rose Bengal test (RBT) and the positive sera were further confirmed by indirect- ELISA. For this purpose, a total of 400 serum samples from dairy cows with history of abortion and various reproductive disorders were collected from the Kurigram district of Bangladesh for the detection of Brucella antibody. The overall prevalence of brucellosis in dairy cattle was 2.25%. Brucellosis in cases of abortion and repeat breeding was 8.3% and 2.8%, respectively. The results shows higher prevalence of brucellosis in cases of abortion followed by repeat breeding, while there was no seropositive cases from other reproductive disorders. Age-wise sero-prevalence was found 3.0% in 2~3 years age group and 2.0% in 4~8 years age group. The prevalence of brucellosis in indigenous and cross-bred cattle was 3.6% and 1.7%, respectively. All the animals detected positive to brucellosis by RBT were not found to be positive by i-ELISA. However, the RBT might be a suitable screening test for the diagnosis of Brucella infection in field condition in Bangladesh. These data will help to develop effective disease prevention strategies.

• Food Science and Preservation
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• v.18 no.3
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• pp.374-382
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• 2011

Aflatoxin ($AFB_1$) is a potent hepatotoxic and hepatocarcinogenic mycotoxin in humans. It is also well-known to be accumulated in animal tissues via various metabolic pathways. This study was conducted to determine the effects of vitamin C on the residual $AFB_1$ in rat sera that were treated with radiation and $AFB_1$. Six week-old male Sprague-Dawley rats were randomly divided into five groups: a control group, $AFB_1$-treated group, the group treated with $AFB_1$ and vitamin C, the group treated with X-ray and AFB1, and the group treated with X-ray and $AFB_1$ with vitamin C. On the first day of the experiment, only one dose of X-rays was exposed to the entire liver at 1,500 cGy. Next, vitamin C was injected at 10 mg/kg body weight via intraperitoneal injection, followed 1 hr later by the administration of 0.4 mg/kg of $AFB_1$ via intraperitoneal injection. These treatments were then administered every three days over a period of 15 days. On the 16th day of treatments, the animals were sacrificed. The contents of $AFB_1$ in rat sera were determined via indirect competitive ELISA and HPLC method. In the quantitative analysis of $AFB_1$ in rat sera via ELISA, $5.17{\pm}0.34$ ng/mL of $AFB_1$ was detected in the $AFB_1$-treated groups, but the amount more significantly decreased to $3.23{\pm}0.76$ ng/mL in the groups treated with $AFB_1$ and vitamin C (p<0.01) than in the $AFB_1$-treated groups. The $AFB_1$ contents of the rat sera of the groups treated with X-ray and $AFB_1$ did not significantly decreased with the administration of vitamin C. The $AFB_1$ content of the rat sera that was analyzed via HPLC showed a tendency similar to that of the content that was analyzed via ELISA. With regard to these data, vitamin C was very effective in reducing $AFB_1$ residue in rat sera.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.793-802
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• 1998

Salmonellosis caused by a number of serotypes of Salmonella is an infectious, acute or chronic, zoonotic disease and characterized by enteritis and diarrhea, septicemia in animal. In these studies we investigated the prevalent serotypes of Salmonella causing animal salmonellosis in Korea and the 71 strains of Salmonella spp. were isolated from materials such as mesenteric lymph nodes, fecal samples from slaughtered animal. With the identification test results, the most prevalent serotypes were, in order, S stanley 31 strains (43.7%), S typhimurium 19 strains (26.8%) and S montevideo 11 strains (15.5%), respectively. And we could establish the method for detection of antibodies to broad variety of Salmonella serotypes. Lipopolysaccharide(LPS) antigen extracted from Salmonella was more sensitive and specific than outer membrane protein antigen from that for detection of Salmonella antibody by using an indirect ELISA. The optimal concentration of antigen was 100ng/ml of LPS, the dilutions of conjugate and serum were 1 : 1,000~2,000 and 1 : 200~400, respectively. The mix LPS-ELISA which was used by mixing LPS from S typhimurium (group B), S choleraesuis (group C) and S enteritidis (group D) were more rapid and effective than that used LPS from individual strain for detection of Salmonella serogroup O4, O7 and O9 antibody at the same time. We could obtain the high values of optical density ($0.73{\pm}0.32$) by mix LPS-ELISA on the farm which had occurred salmonellosis, but very low values of $0.17{\pm}0.06$ on the negative farm of salmonellosis. So, the mix LPS-ELISA may be used to monitor the serological surveillance for the presence of infection with a number of serotypes of Salmonella and would be useful for prevention and control of salmonellosis in animal.

• Journal of Plant Biotechnology
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• v.7 no.4
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• pp.259-265
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• 2005

Indian citrus ringspot virus (ICRSV)-free plants of Kinnow mandarin (Citrus nobilis Lour x C. deliciosa Tenora) were raised from virus-infected plants using unfertilised ovules as explants. Plants were tested by indirect ELISA and RT-PCR before using their explant. An amplified product of 539 bp was obtained by RT- PCR in ICRSV infected plants. Unfertilized ovules were excised from unopened flower buds of plants tested postive for virus and were cultured on Murashige and Skoog's (MS) basal medium supplemented with various concentrations of kinetin (KN) or malt extract (ME). Maximum induction (31.94%) of embryogenic callus was observed on MS medium supplemented with KN ($9.29\;{\mu}M$). Transfer of embryogenic calli to similar media composition resulted in somatic embryogenesis in all cultures, with an average number of 60.36 globular, 17.39 heart and 7.71 cotyledonary-shaped somatic embryos per culture. All cotyledonary shaped embryos developed into complete plantlets within 60 days on transfer to similar medium. Embryogenic callus induction, somatic embryo formation, maturation, germination and plantlet formation were achieved on MS medium supplemented with KN ($9.29\;{\mu}M$) alone. The plantlets derived from somatic embryos were transferred to sterilized soil, sand and vermiculite (3:1:1) mixture. After acclimatization, the plantlets were transferred to screen house and were indexed for ICRSV employing indirect ELISA and RT-PCR and found free of virus. A distinct feature of this study is the induction of somatic embryogenesis from unfertilised ovules to produce virus-free plants.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.133.1-133
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• 2003

Gummy stem blight, caused by Didymella bryoniae occurs exclusively on cucurbits. This fungus has been known not to produce its pycnidium in vitro unless irradiated. Through this study, we optimized cultural conditions for mass-production of pycnidiospore by Metal Halide Lamp irradiation. In brief, the mycelial was cultured at $26^{\circ}C$ on PDA, for 2 days under the darkness, and then the plate was illuminated with MH lamp continuously for 3-4 days at $26^{\circ}C$, a great number of pycnidia was simultaneously formed. Thus produced pycnidiospores were used as immunogen. From fusions of myeloma cell (v-653) with splenocytes from immunifed mice were car ried out. And, two hybridoma cell lines that recognized the immunogen Didymella bryoniae were obtained. One Monoclonal Antibody, Db1, recognized the supernatant and the other monoclonal antibody, Db15, recognized the spore. Two clones were selected which were used to produce ascite fluid two MAb Db1 and Db15, were immunotyped and identified as IgG1 and IgG2b, respectively. Titer of MAb Db1 and MAb Db15 was measured absorbance exceeded 0.5 even at a $10^{-5}$ dilution. The MAbs reacted positively with Didymella bryoniae but none reacted with other of fungi and CMV, CGMMV Sensitivity of MAb was precise enough to detect spore concentration as low as $10^{3}$ well by indirect ELISA characterization of the MAb Db1, Db15 antigen by heat and protease treatments show that the epitope recognized by the MAb Bb1, Db15 were a glycoprotein.

• BMB Reports
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• v.36 no.5
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• pp.493-498
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• 2003

The scFv antibody towards the Burkholderia pseudomallei exotoxin was previously constructed by phage display and exhibited good specificity towards the exotoxin. We report here the optimization of the scFv expression in an E. coli expression system. Four different E. coli strains (ER2537, TG1, HB2151, and XL1-Blue) were examined for optimal expression of the scFv protein. Two types of carbon source (i.e. 0.2% glucose and 0.2% glycerol) were also tested for their ability to induce the scFv expression. Cells that carried the scFv construct were grown at $30^{\circ}C$ and induced with 0.05 mM IPTG. The expression was then monitored by SDS-PAGE, Western blotting, and indirect ELISA. The Western blot profile showed different levels of the scFv expression among the host strains; XL1-Blue exhibited the highest level of the scFv protein expression. Glycerol at a concentration of 0.2% (v/v) significantly increased the scFv protein expression level when compared to 0.2% (w/v) glucose. Further optimization demonstrated that the scFv protein expression in XL1-Blue was the most optimal with a glycerol concentration as low as 0.05%. However, by indirect ELISA, only the scFv protein that was expressed in 0.2% (v/v) glycerol exhibited high specificity towards the Burkholderia pseudomallei exotoxin.