• International Journal of Safety
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• v.7 no.1
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• pp.10-14
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• 2008

For evaluating the radiation degradation of cross-linked polyethylene (XLPE) cable insulation due to the irradiated oxidation, XLPE was irradiated with ${\gamma}$-ray. For each irradiated samples, TGA, DSC, FT-IR, and tensile tests were carried out. Regarding radiation degradation, oxidative process was predominant. TGA, DSC and FT-IR can be useful tools for evaluating the radiation degradation due to the irradiated oxidation because these analyses need only small amount of samples. The results of TGA, DSC and FTIR analyses showed the similar tendency for irradiated degradation. They can be useful tools for evaluating the oxidation of insulating material by non-destructive testing.

• Food Science and Preservation
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• v.6 no.1
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• pp.48-54
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• 1999

The effect of irradiation of heat treatment either alone or in combination on the shelf-life of mixed mountain edible herb drinks (MMEHD) was investigated during storage. The MMEHD made from fresh Spuriopinella bracycarpar, Ligularia fischeri and Aster scaber was gamma -irradiated at doses of 0.1 kGy to 1 kGy. Microbial population, color change, vitamin C content, and sensory quality were evaluated during storage at 4, 25 and 35oC. Heated MMEHD induced the growth of total counts, mold and yeast as compared to the non-heated MMEHD. While some reduction in the microbial growth was observed in 1kGy-irradiated groups of both with or without heating. In both groups, L and b values decreased, but a value increased during storage. Also, heating drinks showed increased L and b values and reduced a value, compared to the non-heating drinks. Non-heated drinks showed 82% loss of vitamin C, whereas 25% loss of vitamin C was occurred in the irradiated drinks during storage at 4oC for 4days. In the meanwhile, non-irradiated heating drinks showed 99% loss of vitamin C, but irradiated heating drinks showed 58-65% reduction of vitamin C. Non-irradiated drinks without heating showed more bright color than irradiated ones, but irradiated drinks showed more enhanced brightness during storage. Also, irradiated drinks showed better falvor, sensory quality, and overall acceptability than non-irradiated drinks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1076-1081
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• 1999

Physicochemical, microbiological, and sensory properties of barleys irradiated by gamma ray at 1.2kGy, 10.1kGy, or 30.5kGy were investigated every 40 days during the storage at 25℃ and 50% relative humidity. Moisture content of the irradiated barleys decreased but crude lipid content increased during the storage. TBA values increased in proportion to the irradiation dose and to the storage period. In Hunter's color, L, a, and b values of 30.5kGy dose irradiated barleys were higher than those of the non irradiated barleys right after irradiation and this trend continued during the storage. Numbers of mesophilic and psychrophilic bacteria in the non irradiated barleys and 1.2kGy dose irradiated barleys were higher than those in the barleys irradiated at 10.1kGy and 30.5kGy during the storage. Numbers of yeasts and molds in the irradiated and non irradiated barleys were low and they did not greatly increase during the storage. In sensory evaluation, acidic odor of the barleys was strong at the 10.1kGy and 30.5 kGy dose irradiation but barley odor and humid odor were not significantly different among the groups depending upon the radiation dose and storage period.

• Journal of the korean veterinary medical association
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• v.26 no.1
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• pp.38-42
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• 1990

The effect of Aloe vera administration(500mg/kg, P.O.) for 21 days on the total white blood cell, packed cell volume, hemoglobin, total protein, serum glutamic pyruvic transaminase and sorbitol dehydrogenase values in cobalt-60 gamma irradiated rats was s

• Korean Journal of Veterinary Research
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• v.15 no.1
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• pp.9-13
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• 1975

In oder to investigate the effects of cobalt-60 gamma irradiation on the postnatal body gains and the other influece of the pregnant mice were subjected to single whole-body gamma irradiation externally. The results obtained were as follows: 1. The all mice of 400, 600, and 800 Rads gamma-irradiated groups showed abortion after prenatal gamma irradiation within 4 to 9 days. 2. There were significant differences of the postnatal body gains of mice between the control and treated groups (100 Rads and 200 Rads gamma irradiation). 3. The relation between gamma-irradiated doses and the postnatal growth rates of mice were inversly proportional.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.143-148
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• 2000

This study was carried out to know the optimum dose of gamma-ray for the induction of mutation in vitro and the characteristics of the mutants induced by gamma-ray in persimmon (Diospyros kaki Thunb.). The LD50 (50% lethal dose) for in vitro shoots of the cultivar, Nishimurawase was between 1 krad and 2 krad and about 1 krad for the cultivar, Ichikikeijiro. As the dose of gamma-ray increased, the length of shoots decreased and necrosis of buds increased. For the cultivar, Nishmurawase, 37.5∼58.3% shoots rooted and the rooting rate and the number of roots per shoot was low in high gamma-ray. The irradiated young plants which were grown in the growth cabinet for 6 weeks were shorter in shoot length and had more branches than non-irradiated plants. The survival rate of irradiated plants grown in the green house for 3 months was 33%, while 77% for control plants.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.135-139
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• 2013

Recently, chronic gamma radiation exposure on biological effects in middle dose-rates have become a serious concern. We investigated the biological effects of middle dose chronic exposure to gamma ray. Fifty male 6-week-old specific free Balb/c mice were randomly divided into five groups (four groups irradiated and one non-irradiated control group). Gamma radiation exposed in Gamma phytotron on Advanced Radiation Technology Institute (Jeongeup, Korea). Irradiation was carried out for 1 or 2 weeks using gamma rays at dose rates of 45 and $50mGy\;h^{-1}$ with total doses 7.56 Gy ($45mGy\;h^{-1}$, 1 week), 8.4 Gy ($50mGy\;h^{-1}$, 1 week), 15.12 Gy ($45mGy\;h^{-1}$, 2 weeks) and 16.8 Gy ($50mGy\;h^{-1}$, 2 weeks). After irradiation, immediately we sacrificed and counted body and organ weights. Moreover we counted spleen cell numbers. Compared with control non-irradiated group, all irradiated groups of body and spleen weights showed significant decreased. However, no significant alteration was observed between same irradiated period groups. In spleen cell numbers, reduced compared to the control group. However, significant alteration was observed between same irradiated period groups ($45mGy\;h^{-1}$, $50mGy\;h^{-1}$). These results demonstrated biological effects according to the radiation dose rate and irradiated period.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.31-42
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• 2014

This study was conducted to evaluate the effect of gamma irradiation (0.4, 0.6, 0.8, 1 and 1.5 kGy) on the microbiological, physicochemical and sensory qualities of imported orange during storage at $3^{\circ}C$ for 60 days. Total aerobic bacteria and yeast/mold counts in non-irradiated oranges were 3.59 and 3.75 log CFU/g, and those counts in irradiated oranges at 1.5 kGy were decreased by 1.75 and 2.26 log CFU/g, respectively. Moreover, those counts were decreased significantly according to a dose-dependent manner after gamma irradiation. The pH revealed no significant difference between the control and irradiated samples; however, titratable acidity was decreased significantly according to a dose-dependent manner and storage time. The vitamin C contents were decreased significantly according to a dose-dependent manner and storage time after gamma irradiation. Further, sensory evaluation testing revealed no significant difference between the control and irradiated samples, except 1.5 kGy. Samples irradiated at 1.5 kGy had the lowest values in color, sweetness, sourness, flavor, texture and overall acceptance. The results suggest that gamma irradiation was effective for ensuring microbiological safety; however, irradiated oranges at 1 and 1.5 kGy did not have good physicochemical and sensory qualities. Therefore, we can use the sample irradiated at 0.4~0.6 kGy as optimum-dose to be minimize on quality changes.

• Toxicological Research
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• v.17 no.2
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• pp.97-106
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• 2001

Korean ginseng products have been fumigated with ethylene oxide (EO) for sterilization and prolongation of storage periods. However, there had been controversies indicating that the consumption of food treated with EO might cause harmful effects in human. Since, in Korea the use of EO gas for food treatment was banned in 1991. Since then, irradiation technique has been developed as an alternative. This study was carried out to investigate the effects of irradiated ginseng on fertility, and reproductive and developmental toxicity. Either EO gas fumigated or gamma-irradiated ginseng was administered to male rats by oral gavage for 63 days during the premating period. Female rats were administered from 14 days before mating to day 20 of gestation or to day 21 of lactation. The exposure amount of irradiation used was 5, 10 and 30 kGy, respectively. There were no treatment related changes of darns in clinical signs, and parturition. No treatment related changes in food consumption, body/organ weights, male/female reproductive and fertility performances were observed. F1 fetuses showed no external abnormality. Reflex/sensory junctions, physical/behavioral development, and reproductive performance of F1 rats were not adversary affected. The results of this study show that gamma-irradiated ginseng, up to 30 kGy, has no adverse effects on the fertility, reproduction and development in Wistar rats.

• Toxicological Research
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• v.17 no.1
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• pp.27-32
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• 2001

Korean ginseng products have been fumigated with ethylene oxide (EO) for sterilization and prolongation of storage periods. However, there had been controversies indicating that consumption of EO treated foods might cause harmful effects in human. In Korea, the use EO gas for food treatment was banned in 1991. Since then, irradiation technique has been developed as an alternative. This study was carried out to evaluate the safety of irradiated ginseng on embryo and fetal developmental toxicity effects in rats. Either EO gas fumigated or $\gamma$-irradiated ginseng was administered to pregnant Wistar rats by oral gavage from gestational day 7 to 17. The amount of irradiation used in this study was 5, 10 and 30 kGy, respectively. There were no treatment related changes of dams in deaths, clinical signs, food consumption and body/organ weight. No treatment related changes in implantation ratio, litter size, sex ratio and body/organ weight of fetuses were observed. Also, no F1fetuses with external, visceral, head and skeletal mal-formation were observed. The results of this study showed that $\gamma$-irradiated ginseng, up to 30 kGy, has no adverse effects on fetal development of rats.