• Food Science and Biotechnology
• /
• v.18 no.5
• /
• pp.1273-1278
• /
• 2009

This study aimed to evaluate the potential allergenicity of Cry proteins in insect-resistant genetically modified (GM) maizes (Bt11, MON810, and MON863) using serum screening tests. Serum samples were obtained from Korean children (0-15 years old) with allergic symptoms who had positive maize-specific IgE. The levels of serum specific IgE was measured by the Phadia ImmunoCAP system and considered as positive when they are 0.35 kU/L or higher. Cry proteins (Cry1Ab in Bt11, mCry1Ab in MON810, and Cry3Bb1 in MON863) were expressed in Escherichia coli and purified for serum screening. The reactivity of purified Cry proteins was confirmed by IgE immunoblots in 50 patients (maize-sensitized patients). There was no reaction between Cry proteins and sera from maize-sensitized patients. Our results suggest that these Cry proteins are not likely to cause allergic reactions. Further studies using more sera from patients with true clinical allergies are needed to evaluate the potential allergenicity of novel proteins in GM maize.

• Korean Journal of Food Science and Technology
• /
• v.35 no.6
• /
• pp.1033-1038
• /
• 2003

Four lines (MON810, GA21, NK603, and TC1507)of genetically modified maize(GMM) were recently approved after a safety-assessment by the Korea Food and Drug Administration (KFDA). In this study, five pairs of specific oligonucleotide primers, based on the gene sequences inserted into maize and zein gene as internal standards, were designed and a method using PCR was developed for monitoring GMM and GMM derived foods circulating in the market. MON810 and GA21 were detected in raw materials of feed and food in the Korean market.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.12
• /
• pp.1761-1768
• /
• 2006

In this study, the comparative effects of transgenic corn (Mon 810 and Event 176) and isogenic corn (DK729) were investigated for their influence on in vitro rumen fermentation. This study consisted of three treatments with 0.25 g rice straw, 0.25 g of corn (Mon810/Event176/DK 729) mixed with 30 ml rumen fluid-basal medium in a serum bottle. They were prepared in oxygen free conditions and incubated at $39^{\circ}C$ in a shaking incubator. The influence of transgenic corn on the number of bacterial population, F. succinogenes (cellulolytic) and S. bovis (amylolytic), was quantified using RT-PCR. Fermentative parameters were measured at 0, 2, 4, 8, 12 and 24 h and substrate digestibility was measured at 12 and 24 h. No significant differences were observed in digestibility of dry matter, NDF, ADF at 12 and 24 h for both transgenic and isogenic form of corns (p>0.05) as well as in fermentative parameters. Fluid pH remained unaffected by hybrid trait and decreased with VFA accumulation as incubation time progressed. No influence of corn trait itself was seen on concentration of total VFA, acetic, propionic, butyric and valeric acids. There were no significant differences (p<0.05) in total gas production, composition of gas (methane and hydrogen) at all times of sampling, as well as in NH3-N production. Bacterial quantification using RT-PCR showed that the population number was not affected by transgenic corn. From this study it is concluded that transgenic corn (Mon810 and Event 176) had no adverse effects on rumen fermentation and digestibility compared to isogenic corn. However, regular monitoring of these transgenic feeds is needed by present day researchers to enable consumers with the option to select their preferred food source for animal or human consumption.

• Food Science and Biotechnology
• /
• v.15 no.1
• /
• pp.148-151
• /
• 2006

Multiplex PCR was performed to simultaneously detect eight different events of genetically modified (GM) maize. Specific primers were constructed from GA21, T25, TC1507, Mon810, Mon863, Event176, Bt11, and NK603 events of GM maize. Using this PCR method, specific GM maize was monitored in commercialized foods and feed.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.6
• /
• pp.1150-1156
• /
• 2004

The GMO (Genetically Modified Organism) labeling system on raw materials has been in Korea since March 2001, and genetically modified organisms (GMOs)-derived foods since July 2001. Therefore, we designed a multiplex PCR method to ascertain the validity of the labeling system and to monitor the status of circulation for genetically modified maize (GM Maize). Five lines of GM Maize (GA21, TC1507, Mon810, NK603, and Bt176) were used, and specific primer pairs were designed to detect each line. Using this method, the different lines of GM Maize were monitored from raw products and processed foods in Korean market. Some of the maize processed foods and raw materials were shown to contain more than one foreign gene. This method was found to be effective for-detecting five different GM Maize in a single reaction.

• Preventive Nutrition and Food Science
• /
• v.17 no.4
• /
• pp.274-279
• /
• 2012

For the quantitative analysis of genetically modified (GM) maize in processed foods, primer sets and probes based on the 35S promoter (p35S), nopaline synthase terminator (tNOS), p35S-hsp70 intron, and zSSIIb gene encoding starch synthase II for intrinsic control were designed. Polymerase chain reaction (PCR) products (80~101 bp) were specifically amplified and the primer sets targeting the smaller regions (80 or 81 bp) were more sensitive than those targeting the larger regions (94 or 101 bp). Particularly, the primer set 35F1-R1 for p35S targeting 81 bp of sequence was even more sensitive than that targeting 101 bp of sequence by a 3-log scale. The target DNA fragments were also specifically amplified from all GM labeled food samples except for one item we tested when 35F1-R1 primer set was applied. A reference plasmid pGMmaize (3 kb) including the smaller PCR products for p35S, tNOS, p35S-hsp70 intron, and the zSSIIb gene was constructed for real-time PCR (RT-PCR). The linearity of standard curves was confirmed by using diluents ranging from $2{\times}10^1{\sim}10^5$ copies of pGMmaize and the $R^2$ values ranged from 0.999~1.000. In the RT-PCR, the detection limit using the novel primer/probe sets was 5 pg of genomic DNA from MON810 line indicating that the primer sets targeting the smaller regions (80 or 81 bp) could be used for highly sensitive detection of foreign DNA fragments from GM maize in processed foods.

• Journal of Life Science
• /
• v.16 no.5
• /
• pp.806-811
• /
• 2006

The regulation of labelling criterion for genetically modified (GM) foods has been enforced since 2001 in Korea. Therefore, GM soybean (GMS) or GM maize (GMM) processed foods must be labeled as GMO derived. We surveyed to see whether this regulation is kept relevantly or not and the distributive statue of GM processed foods. Using the method of polymerase chain reaction (PCR) based on endogenous gene (Le1n, SSIIb), promoter gene (P35S), terminator gene (NOS) and transgenic gene (RRS, Bt11, Bt176, GA21, T25, Mon810), we detected GMS and GMM processed foods circulating at the market in Busan area. Out of total 100 samples, 38 items were showed to be contaminated with recombinant gene by qualitative PCR. Among 82 domestic and 18 imported items, 32 (39.0%) and 6 (33.3%) items were detected with GM ingredients respectively. Also among the 80 soybean and 20 maize processed foods, 23 (28.7%) and 15 (75.0%) foods were sensitive to detect GMS and GMM ingredients respectively. For the qualitative PCR positive foods, we chased identity preservation (IP) certificates. And we verified that the PCR positive crops were grown up, harvested and shipped separately from GMO but just mixed with GMO in the threshold of the non attentional contamination levels (3%). Thus we can not find out any regulation-violent case at all. The results of this study will help to keep the regulations of GM labelling and be informative to consumers who want to know the laboratory results of GMO testing.

• Korean Journal of Food Science and Technology
• /
• v.38 no.5
• /
• pp.605-608
• /
• 2006

Genetically modified (GM) ingredients found in imported raw materials and processed foods were monitored in the province Gyeongin in Korea. The analysis was performed according to "Testing methods for genetically modified foods of food standards and specifications" established in Korea. We received 120 items from the Gyeongin Regional KFDA. Only two of the 120 items analyzed in the samples, were contaminated with GM ingredients. However, we could not analyze the internal standard gene from 12 processed foods. We found that the extracted total DNA of the above 12 samples were extracted and found to be degraded. The total DNA contained a very small fragment of less than 300 base pair. Therefore, it seems that the total DNA is not large enough to serve as the template DNA for PCR analysis.