• Journal of Food Hygiene and Safety
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• v.16 no.2
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• pp.139-144
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• 2001

A 5-day germination test is applicable to detect biological changes in irradiated wheat and barley at low doses. Seeds were irradiated at below 0.5 kGy, husked and placed on distilled water-moistend filter paper in a covered Petri-dish. Water was supplied everyday. To evaluate the growth rate, the length of shoots and roots was measured during germination. In wheat, the shoots of all samples grew well during 5 days, but the shoot length and the daily growth extent decreased with increasing doses. The roots of non-irradiated wheat showed the highest daily growth extent during 5 days and the root length was over 20 mm at 3rd day. In barley, the growth of shoots and roots was retarded at 0.3 kGy or more after 3 days. It was concluded that if the root length was 20mm or longer within 3 days, wheat and barley were identified as non-irradiated. The germination test was proved a promising screening method for the detection of irradiated wheal and barley.

• Korean Journal of Human Ecology
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• v.13 no.1
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• pp.91-96
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• 2004

Effects of irradiation on physical and chemical properties of chicken were investigated. Chicken was irradiated at dose levels of 0, 0.5, 1, 3 and 5 kGy using Co60 source. Irradiation increased drip loss and TBA value. Irradiation decreased L value, and increased a value and b value, indicating that irradiation made chicken darker, more reddish and more yellowish. Irradiation induced the degradation in salt-soluble protein, not water-soluble protein. Any differences in color, odor and tenderness between irradiated and non-irradiated chicken were not perceived by sensory panels.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.103.1-103
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• 2003

건조 생약재의 위생화 수단으로 방사선 조사 기술의 적용 가능성을 검토하기 위하여 감마선 조사 생약의 효능 변화유무를 평가하고자 하였다. 본 연구에서는 감마선 조사 시료와 비조사 시료가 생체의 산화적 손상을 억제하는 효과를 비교하기 위하여 방사선에 의한 산화적 손상에 대한 효과를 측정하였다. 감마선 조사(10 kGy) 생약재(H-113) 및 비조사 생약재(H-113) 추출물을 처리하여 배양한 사람 림프구에 방사선을 조사한 후, 단세포전기영동(single-cell gel electrophoresis, SCGE; comet assay)을 수행하여 DNA 상해 경감정도를 관찰하였다. 또한 방사선 조사 및 비조사 생약재(H-113) 추출물을 투여한 생쥐에 8 Gy의 감마선을 조사한 후, 간에서 지질과산화 정도를 비교·관찰하였다. 한편 DPPH 라디칼과 hydroxyl 라디칼 소거효과를 시험관내에서 상호 비교하였다. 감마선 조사 생약재(H-113)는 단세포전기영동, 지질과산화, DPPH 및 hydroxyl 라디칼 소거시험에서 비조사 생약재 (H-113)와 유사한 효과를 나타내어 효능 차이가 인정되지 않았다. 이는 생약재의 여러 가지 고유 효능 중 일부의 안정성을 확인한 것으로 생각되며, 이러한 결과를 바탕으로 감마선 조사 생약재의 고유 효능의 안정성에 관한 체계적인 연구결과를 얻는다면 생약재의 위생화 수단으로 감마선 조사 기술의 이용이 실용화될 수 있을 것으로 사료된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.843-848
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• 2000

The single cell-gel electrophoresis assay (comet assay) was used to identify irradiated beans. Soy beans, kidney beans, and red beans were irradiated with $^{60}Co$ gamma rays at 0.1, 0.3, 0.5, 0.7, and 1.0 kGy. Beans were peeled out, crushed lightly, and treated with phosphate-buffered saline (PBS) to extract cells. The extracted cell suspension was mixed with agarose gel solution and spread on an agarose precoated slide. After lysis of the cells, they were subjected to microgel electrophoresis for 2 minutes, and then silver-stained. We found that the DNA fragments of the irradiated samples were stretched, migrated out of the cells, and formed tails towards the anode giving the appearance of comets, while the unirradiated or the undamaged cells formed very short or no tails. The tail lengths of irradiated samples were significantly increased as irradiation dose increased at the above 0.3 kGy.

• Journal of Food Hygiene and Safety
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• v.18 no.2
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• pp.51-55
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• 2003

A germination method was used to detect biological changes in gamma-irradated apple, orange, and lemon at low doses at 0.1, 0.3, 0.5, 0.7, and 1.0 kGy. Ten fruit seeds of each sample were placed on moistened cotton and germinated at 3$0^{\circ}C$ for 7 days. Shoot lengths of all fruits were gradually grown for 7 days, but the growth was signficantly slow down by fifth day. During 7 days of germination, the growth of unirradiated fruits were significantly highter than the irradiated fruits. By examining the gamma-Irradiated fruits in this study, a germination method could be possibly one of the screening test to identify irradiated fruits.

• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.76-81
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• 2001

The germination test was used to detect biological changes in irradiated rice and glutenous rice at low doses. Grains were irradiated at below 0.5 kGy, husked and placed on distilled water moistend filter paper in a covered petri-dish. A germination test of 20 grains was carried out at room temperature for 5 days. The shoots and roots of non-irradiated rices grew well in comparison with those of irradiated rices above 0.3 kGy. The roots of rices were more sensitive to irradiation than the shoots, and the growth of roots was significantly decreased with the increasing doses. In glutinous rices, the growth of shoots and roots was retarded by irradiation at 0.2 kGy or more after 3rd days. We concluded that if the shoot or root length is 10 mm or longer within 5 day, the rices and glutinous rices are identified as non-irradiated.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.531-537
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• 2000

The simple microgel electrophoresis of single cells, a 'comet assay', on fruit seeds enabled the rapid identification of irradiated fruits by comparing the intact non-irradiated cells and the damaged cells of irradiated fruits. Grapes and plums were irradiated with 0.1, 0.5, 0.7, 1.0 kGy and strawberries, peaches, apples, and nectarines were irradiated with only 1.0 kGy. Seeds were isolated, crushed, and the suspended cells were embedded in an agarose layer. After lysis of the cells, they were subjected to microgel electrophoresis for 2 minutes, and then stained. The DNA radiation-induced fragmentation of all the fruits stretched and migrated out of the cells forming a tail toward the anode giving the appearance of a comet, while the undamaged cells appeared as intact nuclei without tails. Grape and plum seeds irradiated at 0.5 kGy and higher showed significant increases in tail length. With increasing the irradiation doses, longer extention of the DNA from the nucleus toward the anode was observed. Strawberry, peach, apple, and nectarine seeds irradiated with 1.0 kGy also showed the longer tails than non-irradiated ones. DNA comet assay as a rapid and inexpensive screening technique could be an officially validated method for the detection of irradiated fruits.

• Proceedings of the Korean Statistical Society Conference
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• 2004.11a
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• pp.149-154
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• 2004

이 논문에서는 표본조사에서 자주 사용되는 표본의 대표성, 비편향성, 그리고 효율성에 개넘에 대하여 고찰하였다. 표본의 대표성은 조사단위의 포함확률로 표현되며 조사모집단의 포함범위와 연관이 있는 반면, 비편향성과 효율성은 표집설계와 추정량에 관련된 개념이다. 비편향성과 효율성은 표본의 대표성을 전제로 하며 가중치 부여로 나타난다

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.178-184
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• 1999

Physicochemical, microbiological, and sensory properties of corns irradiated by gamma-ray at 1.2 kGy, 10.1 kGy or 30.5 kGy were investigated every 40 days during the storage at 25$^{\circ}C$ and 50% relative humidity. The moisture content of irradiated corns decreased and crude lipid content increased during the storage. Acid values of the irradiated corns were not significantly different from those of the nonirradiated corns but acid values generally increased during the storage. TBA values of irradiated corns increased in proportion to the irradiation dose and to the storage period. Numbers of mesophilic and psychrotrophic bacteria in the nonirradiated corns and 1.2 kGy dose-irradiated corns were higher than those in the corns irradiated at 10.1 kGy and 30.5 kGy at the late storage. The number of yeasts and molds in the nonirradiated corns were higher than those in the irradiated corns during the storage. In Hunter's color, L values of irradiated and nonirradiated corns decreased with the storage period and b values of all groups decreased except the group irradiated at 30.5 kGy. In sensory evaluation, fresh corn odor of the irradiated group was significantly different from those of the nonirradiated one stored for only 0 day and 200 days but raw corn odor and acidic odor were not significantly different among the groups depending upon the radiation dose and storage period.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1002-1006
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• 2002

Germination method was used to screen the biological changes in soybean, kidney bean, and red bean caused by gamma irradiation. Beans were irradiated at 0.1, 0.3, 0.5, 0.7, and 1.0 kGy. Ten beans of each sample were placed on moistened cotton and germinated at $30{\circ}C$. The root lengths were measured daily for 5 days. Root lengths of all beans grew continuously for 5 days, but the growth rate of irradiated beans decreased significantly from fourth day. Unirradiated beans showed the highest growth rate during 5 days of germination. Gamma-irradiated beans could be screened by measuring the daily growth rate and root length during germination.