• Journal of Life Science
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• v.28 no.7
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• pp.835-840
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• 2018

Quantitative determination of the protein expression levels is one of the most important parts in assessment of the safety of foods derived from genetically modified (GM) crops. Overexpression of AtCYP78A7, a gene encoding cytochrome P450 protein, has been reported to improve tolerance to abiotic stress, such as drought and salt stress, in transgenic rice (Oryza sativa L.). In the present study, an enzyme-linked immunosorbent assay (ELISA) kit for diagnosing AtCYP78A7 protein including AtCYP78A7-specific monoclonal antibody was developed. GST-AtCYP78A7 recombinant protein was induced and purified by affinity column. Four monoclonal antibodies (mAb 6A7, mAb 4C2, mAb 11H6, and mAb 7E8) against recombinant protein were also produced and biotinylated with avidin-HRP. After pairing test using GST-AtCYP78A7 protein and lysate of rice samples, mAb 4C2 and mAb 7E8 were selected as a capture antibody and a detecting antibody, respectively, for ELISA kit. Product test using rice samples indicated that percentages of detected protein in total protein were greater than 0.1% in AtCYP78A7-overexpressing transgenic rice (Line 10B-5 and 18A-4), whereas those in negative control non-transgenic rice (Ilpum and Hwayoung) were less than 0.1%. The ELISA kit developed in this study can be useful for the rapid detection and safety assessment of transgenic rice overexpressing AtCYP78A7.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6335-6338
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• 2015

Background: Cancers have dysfunctional redox regulation resulting in production of reactive oxygen species (ROS), damaging DNA, RNA and free NTPs, and causing the accumulation of oxidative nucleic acids in cytoplasm. The major types are 8-oxo-7,8-dihydroguanine(8-oxoGsn) in RNA and 8-oxo-7,8-dihydro-2' deoxyguanosine(8-oxodGsn) in Mt-DNA. The MTH1 protein sanitizes oxidized nucleotide pools from NTPs to monophosphates, preventing the occurrence of transversion mutations. This study concerned cytoplasmic 8-oxodGsn/Gsn and MTH1 expression in gastric cancer and para-cancer tissues and elucidated roles of nucleic-acid oxidation and anti-oxidation. Materials and Methods: A polymer HRP detection system was used to detect 8-oxo-Gsn/dGsn and MTH1 expression in 51 gastric cancer and para-cancer tissue samples. Analyses of patient clinical and pathological data were also performed. Results: The expression of MTH1 and the 8-oxo-dGsn/Gsn ratio were significantly higher in cancer tissues than para-cancer tissues (P<0.05). Cytoplasmic 8-oxo-Gsn and MTH1 were both found to positively correlate (P<0.05) with tumor differentiation, while no significant associations were found with gender, age, invasion depth, lymph node metastasis and clinical stage (P>0.05). Conclusions: We found 8-oxo-dGsn/Gsn and MTH1 are both highly expressed in gastric cancer tissues, especially in well differentiated lesions. In addition, oxidated mtDNA is prevalently expressed in gastric cancers, while 8-oxo-Gsn expression in cytoplasmic RNA is a bit lower, but more selectively.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.111-115
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• 2009

In this study we analysed for peanuts in processed foods using an enzyme-linked fluorescent immunoassay (ELFA), and compared the results with labeled ingredients. Crude peanut protein (CPP) was immunized into rabbits to produce specific antibodies(Ab). A sandwich ELFA was established using anti-CPP Ab and Ab-horseradish peroxidase (HRP) conjugate. The cross-reactivities of the Ab toward CPP, peanuts, almonds, soybeans, and walnuts were 100, 9.8, $1.1{\times}10^{-2},\;4.4{\times}10^{-3}$, and 0%, respectively. The samples included 19 items consisting of biscuits, snacks, chocolates, and so on. The results from the sandwich ELFA showed that peanuts were contained in 7 of the processed food items, among which, 5 items were labeled as having peanuts present but 2 items were not. One of the 2 items that was peanut-detected but unlabeled was a biscuit labeled to contain almonds and assayed to contain $2.1{\times}10^{-3}%$ peanuts, which might have been due to the weak cross-reactivity of the Ab toward almonds. The other item was a snack labeled to contain soybeans and assayed to contain 0.098% peanuts, which might have been due to peanut cross-contamination during processing, since the crossreactivity of the Ab toward soybeans was very weak. These results suggest that ELFA is a good tool to detect peanuts in processed foods, and allergens in certain processed foods should be labeled correctly.