• Preventive Nutrition and Food Science
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• 제6권2호
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• pp.91-95
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• 2001

Competitive indirect enzyme linked immunosorbent assay (Ci-ELISA) was used to obtain the preliminary data for the detection of irradiated beef. Ci-ELISA was individually formatted with polyclonal antibodies produced from 2 kinds of bovine proteins, myosin and bovine serum albumin (BSA). Beef round, loin and tender loin were vacuum-packaged and subdivided into 3 groups of 1) irradiation; 2) irradiation and chilled at 4$^{\circ}C$ for 7 day; 3) irradiation and frozen at 2$0^{\circ}C$ for 2 months to observe the changes under different storage and/or distribution conditions. Irradiation was performed at 3, 5 and 7 kGy. Protein solutions prepared from the sample were tested by formatted Ci-ELISA. Detected concentrations of myosin and BSA decreased with the increased irradiation dose in all samples with different reduction rates. Myosin was more susceptible to freezing than BSA. Samples irradiated at 5 kGy or above could be differentiated from non-irradiated ones by Ci-ELISA. These results indicate that immunological assay can be used as a detection method for irradiated beef.

• 한국미생물·생명공학회지
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• 제22권4호
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• pp.430-435
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• 1994

In order to develop an enzyme-linked immunosorbent assay (ELISA) for zearalenone (ZEA) in corn, we produced antisera by immunizing rabbits with ZEA-6'-carboxymethyloxime-BSA, purified polyclonal anti ZEA antibodies, and subsequently established a competitive indirect ELISA. The antibodies showed low cross-reactivity of 9.6~1.4% against ZEA analogues such as $\alpha$-zearalenol, $\beta$-zearalenol, $\alpha$-zearalanol, and $\beta$-zearalanol. From the standard curve of the ELISA for ZEA in corn, the detection range was found to be 0.3~1, 000 ng/ml. When artificially contaminated corns were assayed by the ELISA, the average recovery of ZEA spiked to 30~1, 000 ng/g was 109% (96~123%), although that of ZEA spiked to 10 ng/g was somewhat high (258%). The average coefficient of variation (CV) of the recovery was 18.0% (0.9~28.3%). When 9 corn samples naturally contaminated were assayed 3 times, the average CV of the determinitions was 27.7% (9.3~52.4%). Therefore, the ELISA was elucidated to be a practical tool for the detection of ZEA of 30 ng/g and more from corn.

• 한국식품위생안전성학회지
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• 제8권4호
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• pp.205-214
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• 1993

The monoclonal antibody to chloramphenicol(CAP) was produced to develop an enzyme-linked immunosorbent assay(ELISA) for residual CAP. An immunogen(CAP-BSA) was prepared by immunogen, antibody titer was measured by indirect ELISA. Spleen cells form the immunized mouse were fused with SP2/OAg14 myeloma cells. Among hybridomas selected in HAT media, 6 clones shown high antibody titer to CAP were subjected to cloning by limit dilution, and all of the monoclonal antibodies(MCA1, 2, 3, 4, 5, 7 and 9) produced by each clone were identified as IgG1 by ELISA isotyping analysis. Competitive ELISA condition was established by using the purified monoclonal antibody MCA1 as primary antibody and CAP-HSA conjugate as coating antigen. Standard curve of CAP(n=28) showed that the lowest detection limit of CAP is 20ng/ml level. The cross-reactivities of the 6 monoclonal antibodies showed that CAP sodium succinate. CAP base, P-nitrophenol, and p-nitrobenzyl alcohol were 89∼178, 0.050∼2.237, 0.056∼0.794 and 0.013∼7.939%, respectively. No cross-reactivities were observed with phenylalanine, tyrosine, glutamine, thiamphenicol, neomycin, streptomycin, gentamicin, sulfamethazine, sulfathiazole, chlortetracycline and p-aminobenzoic acid.

• 한국식품과학회지
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• 제35권6호
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• pp.1209-1215
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• 2003

가시오가피 냉침 추출물에서 면역자극활성을 가지는 지표물질을 분리하고자, gel chromatography를 수행하여 비장세포에 대한 증식활성을 가지는 EN-SP을 분리하였고, 생화학적 분석 결과 단백 다당 물질임을 확인하였다. 가시오가피 추출물 내에서 지표물질로서 EN-SP 성분을 정량하기 위하여 경쟁적 ELISA법을 개발하여 다음과 같은 결과를 얻었다. 경쟁적 ELISA법을 이용하여 EN-SP-HRP conjugate의 희석농도를 1000배로 결정하였으며, EN-SP의 표준곡선을 작성한 결과 검출범위는 $0.2{\sim}20\;{\mu}g/mL$으로서 측정감도는 $0.2\;{\mu}g/mL$이었다. 이러한 표준곡선의 정당성 평가를 위하여 정량된 EN-SP를 통한 재현성 실험에서 $5\;{\mu}g/mL$ 이하의 농도에서 intra assay 경우 C.V. 값은 $6.13{\sim}8.81%$, bias는 평균 -3.7%를 보였으며, inter assay에서도 C.V. 값과 bias 모두에서 10%이내로 비교적 우수한 재현성을 보였다. 작성된 표준곡선을 바탕으로 유사물질인 오가피의 $4^{\circ}C$ 추출물들의 EN-SP의 함유량을 조사한 결과 EN-SP 성분은 주로 가시오가피 외피에서만 높은 함유량을 보였다. 동일한 추출물의 macrophage 자극에 의한 cytokine 유도활성 실험결과, EN-SP 성분을 함유하는 가시오가피의 수피 추출물만 IL-12 및 $TNF-{\alpha}$를 생산하는 면역자극활성을 나타냄으로서 EN-SP 성분은 가시오가피에서 면역자극활성을 나타내는 지표물질로의 가능성이 제시되었다.

• Journal of Biosystems Engineering
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• 제28권6호
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• pp.505-510
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• 2003

In Korea, due to its broad efficacy as a systemic insecticide, imidacloprid has been widely used in rice paddies to control sucking insects, soil insects, and some chewing insects and in apple orchards to control various insects pests. To quantify the imidacloprid residue concentrations, samples are assayed in vitro using enzyme-linked immunosorbent assays(ELISA). These assays generally require several hours to perform. As a biosensor, a competitive imidacloprid ELISA was modified to measure insecticide concentrations. It was found that a total assay time of 15 min(10-min antibody-antigen binding, and 5-min substrate development) is sufficient for monitoring imidacloprid concentrations. Further work is needed to improve the sensitivity of the measurement protocol.

• Bulletin of the Korean Chemical Society
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• 제23권4호
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• pp.605-609
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• 2002

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative detection of organophosphorus insecticide cyanophos. An analogue (hapten) of cyanophos was synthesized and was coupled to BSA to produce polyclonal antibodi es from rabbits. The antisera were screened against another hapten coupled to ovalbumin (OVA). Using the sera of highest specificity, an antigen-coated ELISA was developed, which showed an I50 of 310 ng/mL with the detection limit of 20 ng/mL. The antibodies showed negligible cross-reactivities with other organophosphorus pesticides except for parathion-methyl, which makes the assay suitable for the selective detection of cyanophos.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1399-1426
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• 2002

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative detection of the organophosphorus insecticide bromophos. Three bromophos analogues (haptens) were synthesized and were coupled to carrier proteins to use as immunogens or coating antigens. Rabbits were immunized with either one of two haptens coupled to bovine serum albumin (BSA) for production of polyclonal antibodies, and the sera were screened against one of the haptens coupled to ovalbumin (OVA). Using the serum with highest specificity and an enzyme tracer, an antibody-coated ELISA was developed, which showed an $IC_{50}$ of 40 ng/mL with a detection limit of 7 ng/mL. The antibodies in this assay showed negligible cross-reactivity with other organophosphorus pesticides except with the insecticides chlorpyrifos and fenitrothion.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.176-176
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• 1996

축산식품중에 잔류하고 있는 sulfamethazine을 검출하기 위하여 sulfamethazine에 대한 단클론항체를 생산하고 이를 이용하여 효소면역측정법을 개발하였다. 면역원은 sulfamethazine에 KLH를 그리고 흡착항원은 BSA를 glutaraldehyde법으로 결합시켰다. 면역원으로 Balb/c mouse를 면역시킨 다음 비장 형질세포률 얻어 myeloma cell과 융합하여 융합잡종세포를 만들었다. Sulfamethazine에 대한 항체를 분비하는 융합잡종세포를 단계회석법과 ELISA를 이용하여 cloning하여 D2, A9, B8, Bl 클론을 얻었다. 이들 클론에서 얻어진 단클론항체를 사용하여 indirect competitive ELISA를 실시하여 표준곡선을 작성하여 본 결과 농도의존성 곡선을 얻을 수 있었다. 4클론중에서 A9 클론을 사용하여 다른 유사한 sulfonamide듣과 p-aminobenzoic acid와 교차반응을 조사한 결과 sulfamerazine에 12.5%의 교차반응을 보였으나 다른 설파제에 대해서는 교차 반응을 보이지 않았다.

• 한국식품위생안전성학회지
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• 제12권4호
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• pp.281-287
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• 1997

We have reported a sensitive, specific and simple direct competitive ELISA method to detect aflatoxin in agricultural commodities. We evaluated the ELISA for practical use to detect aflatoxins contaminated in the domestic and foreign agricultural commodities. The detection limits of the direct ELISA for residual aflatoxins in rice, pine nuts, corns, almonds, bean nuts, and pistachio were 10 ppb and in peanuts and cashew nuts were 20 ppb, which were elucidated from the standard curves of ELISA for aflatoxin fortified into the agricultural commodities. Residue studies of naturally contaminated aflatoxins in the agricultural commodities were also carried out by using direct ELISA. As the results of the studies, it was revealed that there were no residues of aflatoxins in 20 rice samples produced in south Korea, 20 pine nut samples in south Korea (9 samples), USA (1 sample) and China (10 samples), each of 20 almond, pistachio and bean nut samples in USA. However, aflatoxin residues were detected in corn samples imported from north Korea (350∼585 ppb in 2 of 3 samples), from USA (109*326 ppb in 6 of 6 samples) and domestic corns (61-326 ppb in 7 of 17 samples). The toxins were contaminated in corn imported from USA for popcorn (17∼20 ppb, in 3 of 10 samples) whereas no residues were detected in corn from south Korea and China. In case of cashew nuts imported from India, 11.4∼23.1 ppb of aflatoxins were detected in 4 from 20 samples. Most of the contaminated foods were harvested before 1995. Thus, hygienic managements of the foods should be required during storage and circulation at market.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.256-261
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• 2004

In order to detect chitooligosaccharides (COS) in soybean paste, tandem immunoaffinity chromatography and enzyme-linked immunosorbent assay (ELISA) were developed. Polyclonal anti-chitooligosaccharides mixture (CaSM) antibody specific to COSM was attached to Sepharose gel for initial sample cleanup and concentration of COS in soybean paste. COS was eluted and quantified by competitive direct ELISA (cdELISA). Average ELISA recoveries from the column using binding buffer spiked with COSM at levels of 0.5, 2.0, 5.0, and $10.0\mu$g/ml were 79.8, 72.0, 77.7, and 60.6%, respectively, with a mean recovery of 72.5%. Mean inter-well and inter-assay coefficients of variation (CV) were 7.7% and 10.3%, respectively. Average recoveries from soybean paste spiked with COSM at levels of 2, 6, 20, and $60\mu$g/g were 115, 91.7, 91, and 73.3%, respectively, with a mean recovery of 92.8%. Mean inter-well and inter-assay CV were 12.9% and 16%, respectively. The COS was detected from 24 out of 25 homemade Korean soybean paste samples at an average of $14.0\mu$g/g (n, 25; range, $0-51.2 \mu$g/g) and from 13 out of 14 commercially made soybean paste samples at an average of $4.1\mu$g/g(n, 14; range, $0-18.4\mu$g/g). The tandem immunoaffinity chromatography-cdELISA that was developed in this study showed that the level of COS eluted from homemade soybean paste was higher than that of the commercially made ones. In addition, the level of COS eluted from commercially available soybean paste in Korea was higher than that of the ones in Japan.