• Food Science and Biotechnology
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• v.16 no.6
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• pp.1011-1017
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• 2007

Saeujeot (salted and fermented shrimp) and kimchi are traditional Korean fermented foods. Even though shrimp have often induced severe allergic reactions in sensitized individuals, few studies have investigated the allergenicity of shrimp. The aim of this study was to observe the changes of pH and allergenicity of raw shrimp (Acetes japonicus) and saeujeot in cabbage kimchi during fermentation using competitive indirect enzyme-linked immunosorbent assay (Ci-ELISA). Fermentation was carried out at different temperatures (25, 15, and $5^{\circ}C$). The pH of cabbage kimchi added with raw shrimp or saeujeot slowly decreased at lower temperature ($5^{\circ}C$) at the end stage of the fermentation process. The binding ability of serum obtained from patients allergic to raw shrimp against shrimp tropomyosin and saeujeot in kimchi rapidly decreased during longer fermentation periods and higher temperature ($25^{\circ}C$). In conclusion, the allergenicity of both raw shrimp and saeujeot in kimchi decreased during fermentation but the decrease in allergenicity of saeujeot was greater than observed for raw shrimp.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1605-1608
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• 2003

To development an immunodetection method for DDT, 1,1,1-trichloro-2,2-bis(4-chorophenyl)ethane (p,p'-DDT) and its metabolites (p,p'-DDA, p,p'-DDE, p,p'-DDD), five derivatives of DDT haptens have been synthesised and characterized as coating ligands for antibody evaluation. The appropriate lengths of linkers were introduced to investigate a matching pair of coating ligand and antibody. Among these hapten derivatives, 2,2-bis(4-chlorophenyl)acetic acid (DDA), 5,5-bis(4-chlorophenyl)-5-hydroxypentanoic acid (DDHP) and 5,5-bis(4-chlorophenyl)-5-chloropentanoic acid (DDCP) were conjugated with keyhole limpet hemocyanin (KLH) for its use as an immunogen. The bovine serum albumin (BSA) conjugates of these derivatives were prepared as a coating ligand for monoclonal antibody screening. Fifteen monoclonal antibody clones were screened using these probes. 6,6-Bis(4-chlorophenyl)-6-hydroxyhexanoic acid (DDHH) and 3-[6,6-Bis(4-chlorophenyl)-6-hydroxyhexanoylamino]propanoic acid (DDHHAP), in addition to the above hapten derivatives, were conjugated to ovualbumin (OVA) and bovine serum albumin (BSA) for their use as coating ligands to measure the titration level of the antibody and the displacement of free analytes. The indirect competitive ELISA results indicate that the titration level and free analyte displacement were greatly influenced by the DDT derivatives and carrier proteins used. Three matching pairs of monoclonal antibodies and coating ligands were selected for the DDT immunoassay: antibody clone 1A3 and coating ligand DDA-OVA, 1A1 and DDHHAP-BSA, and 1A4 and DDHP-OVA.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.306-311
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• 2008

The aim of this work was to examine the reduction in antigenicity of milk proteins in powdered milk by gamma irradiation which is increasingly used for food safety. Skim milk powder samples were exposed to irradiation doses of 1, 5, and 10 kGy. A greater reduction of ${\alpha}_{S1}$-casein and ${\beta}_{A1}$-casein was found than ${\alpha}_{S0}$-casein and ${\beta}_{A2}$-casein by capillary electrophoresis. Competitive indirect ELISA and passive cutaneous anaphylaxis tests using guinea pigs showed a reduction in antigenicity of powdered milk by 10kGy gamma irradiation. These results indicated that gamma irradiation reduce allergenicity of milk proteins by structural changes of ${\alpha}_{S1}$-casein and ${\beta}_{A1}$-casein, and can be useful for dairy products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.990-996
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• 2006

This research was conducted to evaluate the changes in allergenicity of shrimp by physical treatments using competitive indirect enzyme-linked immunosorbent assay (Ci-ELISA). Shrimp was subjected to physical treatments such as high hydrostatic pressure (HHP), sonication, autoclave and microwave. Heat-stable protein (HSP) purified from raw shrimp was used as a major allergen. The binding ability of monoclonal IgG and shrimp-allergic patients' IgE to HSP treated with HHP decreased, increasing the pressure up to 400 MPa. Especially, it became less than 50% at 400 MPa. The binding ability of mAb to HSP treated with sonication (10, 20, 30 and 60 min) decreased with the treated time. Especially, it became less than 60% with the treatment for 60 min. The allergenicity change of HSP treated with autoclave and microwave little decreased. The binding ability of mAb to HSP during the treatment for 20 min became more than 70%. The results suggest that allergenicity of HSP in raw shrimp be more easily lost by HHP or sonication treatment than by autoclave or microwave treatment.

• Food Science and Preservation
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• v.21 no.5
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• pp.747-756
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• 2014

The objective of this study was to examine the effects of vitamin C on the formation of aflatoxin $B_1$ ($AFB_1$)-DNA adduct and $AFB_1$-induing cellular oxidative damage in rat livers treated with radiation and $AFB_1$. Six-week-old male Sprague-Dawley rats were randomly divided into five groups: the control group, the $AFB_1$-treated group, the group treated with $AFB_1$ and vitamin C, the group treated with X-ray and $AFB_1$, 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 an hour later by the administration of 0.4 mg/kg of $AFB_1$ via intraperitoneal injection. These treatments were administered every three days for 15 days. On the 16th day, the animals were sacrificed. The $AFB_1$ contents of the rat sera were determined via indirect competitive ELISA. In the quantitative analysis of $AFB_1$ in the rat sera via ELISA, $5.17{\pm}0.34ng/mL$ of $AFB_1$ was detected in the $AFB_1$-treated groups, but the amount decreased more significantly to $3.23{\pm}0.76ng/mL$ in the groups treated with $AFB_1$ and vitamin C (p<0.01) than in the $AFB_1$-treated groups. The effect of vitamin C on $AFB_1$-DNA adduct formation was determined via ELISA. The values of $AFB_1$-DNA adduct formation were $9.38{\pm}0.41ng/mL$ in the $AFB_1$-treated groups, but the amount decreased more significantly to $5.28{\pm}0.32ng/mL$ in the groups treated with $AFB_1$ and vitamin C (p<0.01) than in the $AFB_1$-treated groups. Immunohistochemistry revealed that the accumulation of the $AFB_1$ was not observed in the normal liver tissue (G1). The $AFB_1$-positive materials were observed in the central vein and the portal vein of the liver tissue from the $AFB_1$(G2) treatment or the X-ray and $AFB_1$(G4) co-treatment, but the $AFB_1$-positive materials were observed weakly in the group treated with vitamin C (G3 and G5). These results indicate that vitamin C had ameliorating effects on the $AFB_1$ accumulation of liver tissue.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.238-244
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• 2009

Food allergy is a serious nutritional problem in both children and adults. Therefore, food allergenicity reduction methods are greatly needed. The allergenicity is altered by various manufacturing processes, and the digestibility of food proteins can be affected by food processing. This study was conducted to investigate the effect of in-vitro digestibility on the allergenicity of autoclaved market pork sausages using pepsin (30min) and trypsin (5, 30, 60, 90, and 120min). The binding ability of the porcine serum albumin (PSA) from sausages A and B significantly decreased by about 30 and 23%, respectively, after autoclave treatment (121; 5, 10, and 30 min). After the pepsin and trypsin treatments, the binding ability of products A and B at 30 min decreased. These competitive indirect enzyme-linked immunosorbent assay (ci-ELISA) results corresponded well with the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting results. The results demonstrated that the allergenicity of pork sausages considerably decreased after autoclave treatment, and were also maintained or decreased after enzyme treatment. Accordingly, autoclave treatment represents a promising processing technology for the reduction of the allergenicity of diverse food products.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.669-675
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• 2001

The objective of this study was to examine the effects of antioxidant vitamins on the formation of $AFB_{1}-DNA$ adduct and $AFB_{1}-inducing$ cellular oxidative damage. Intraperitoneal(i.p.)injections of 10 mg/kg vitamin C(VC) and 63.8 mg/kg vitamin E(VE) were repeatedly administrated 4 times with 2 days interval to 6 week old male ICR mice. After one hour of vitamin treatments, 0.4 mg/kg $AFB_1$ was injected in $AFB_1$ plus vitamin treated groups by same way. On the other hands, $AFB_1$ treated group was only injected with $AFB_1$ by the same method described above without vitamins. According to quantitative analysis of the $AFB_1$ in mice serum by indirect competitive ELISA, 12.28 and 18.78 ng/mL were detected in $AFB_1-treated$ groups, but 7.60 and 4.85 ng/mL in $AFB_1$ plus VC and VE treated groups, respectively. 23.78, 25.48 ng/mL of $AFB_1-DNA$ adduct were detected in mice liver of $AFB_1$treated groups, while 5.26, 7.81 ng/mL in $AFB_1$ plus VC and VE treated groups, respectively. Consequently, the differences in the concentrations of $AFB_1$ related materials between vitamin treated and non-treated groups were significant. Immunohistochemistry revealed brownish infiltration of $AFB_1$ around central vein and sinusoid in $AFB_1-treated$ group. This manifestation was distinctly reduced in $AFB_1$ plus VC and VE treated groups.

• IMMUNE NETWORK
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• v.3 no.2
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• pp.126-135
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• 2003

Background: One of the important factors in the prognosis of chronic hepatitis B patient is the degree of replication of hepatitis B virus (HBV). It has been known that HBV DNA polymerase plays the essential role in the replication of HBV. HBV DNA polymerase is composed of four domains, TP (Terminal protein), spacer, RT (Reverse transcriptase) and RNaseH. Among these domains, tyrosine, the $65^{th}$ residue of TP is an important residue in protein-priming reaction that initiates reverse transcription. If monoclonal antibody that recognizes around tyrosine residue were selected, it could be applied to further study of HBV replication. Methods: To produce TP-specific scFv (single-chain Fv) by phage display, mice were immunized using synthetic TP-peptide contains $57{\sim}80^{th}$ amino acid residues of TP domain. After isolation of mRNA of heavy-variable region ($V_H$) and light-chain variable region ($V_L$) from the spleen of the immunized mouse, DNA of $V_H$ and $V_L$ were obtained by RT-PCR and joined by a DNA linker encoding peptide (Gly4Ser)3 as a scFv DNA fragments. ScFv DNA fragments were cloned into a phagemid vector. scFv was expressed in E.coli TG1 as a fusion protein with E tag and phage gIII. To select the scFv that has specific affinity to TP-peptide from the phage-antibody library, we used two cycles of panning and colony lift assay. Results: The TP-peptide-specific scFv was isolated by selection process using TP-peptide as an antigen. Selected scFv had 30 kDa of protein size and its nucleotide sequences were analyzed. Indirect- and competitive-ELISA revealed that the selected scFv specifically recognized both TP-peptide and the HBV DNA polymerase. Conclusion: The scFv that recognizes the TP domain of the HBV DNA polymerase was isolated by phage display.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.848-853
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• 2001

This research was conducted to study the effects on antigenicities (allergenicity) and structural changes of gamma-irradiated hen’s egg albumin (ovalbumin, OVA) by heating. Three groups of OVA solution (2.0 mg/mL) were prepared; 1) heat treatment; 2) irradiation after heating; 3) heating after irradiation. Samples were isothermally heated and/or irradiated at the absorption dose of 10 kGy. Competitive indirect ELISA was individually formatted with egg-allergic patients IgE (P-IgE), and mouse murine monoclonal IgG (M-IgG) and rabbit polyclonal IgG (R-IgG) for evaluating bindinhg abilities of antibodies to OVA in the sample solutions. Binding abilities of antibodies to thermally denatured OVA were changed : R-IgG to the sample treated with above 6$0^{\circ}C$, M-IgG to that above 7$0^{\circ}C$, and P-IgE to that above 8$0^{\circ}C$, respectively. P-IgE did not well recognize OVA heated at 8$0^{\circ}C$ and the above. However, binding abilities of M-IgG and R-IgG highly in creased. Significant differences of binding abilities were not observed in all samples with the combination of heat treatment and irradiation, regardless the order of the treatment. Turbidity of samples in creased both by heating and by irradiation, and the increase by irradiation was much higher than by heating. These results showed that allergenicity of OVA reduced by gamma irradiation was not affected by heating.