• Molecules and Cells
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• v.27 no.2
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• pp.263-268
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• 2009

Gamma knife surgery (GKS) is used for the treatment of various human brain disorders. However, the biological effects of gamma ray irradiation on both the target area, and the surrounding tissues are not well studied. The effects of gamma ray exposure to both targeted and untargeted regions were therefore evaluated by monitoring gene expression changes in the unilateral irradiated (60 Gy) and contralateral un-irradiated striata in the rat. Striata of irradiated and control brains were dissected 16 hours post-irradiation for analysis using a whole genome 44K DNA oligo microarray approach. The results revealed 230 induced and 144 repressed genes in the irradiated striatum and 432 induced and 239 repressed genes in the unirradiated striatum. Out of these altered genes 39 of the induced and 16 of the reduced genes were common to both irradiated and un-irradiated tissue. Results of semiquantitative, confirmatory RT-PCR and western blot analyses suggested that ${\gamma}$-irradiation caused cellular damage, including oxidative stress, in the striata of both hemispheres of the brains of treated animals.

• Journal of radiological science and technology
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• v.3 no.1
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• pp.95-105
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• 1980

In this paper, the author studied the histological changes of the midgut cells of fall webworms(Hyphantria cunea Drury) through 1.75-7 krad of the whole body gamma irradiation according to their metamorphosis by comparing the contol group with the irradiated one through an optical microscope. Here the results were as follows: 1. The epithelium of midgut was composed of columnar, goblet and regenerative cells. 2. The effects of gamma irradiation were varied with the dosages and the stages during the metamorphosis. 3. The degree of histological change mode by irradiation was increased with the dosages. 4. Radiosensitivity was the highest in both last-stage larva and 8-day-old pupae.

• Food Science and Industry
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• v.53 no.3
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• pp.264-276
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• 2020

Ionizing radiation is one of the efficient non-thermal pasteurization methods. The US Food and Drug Administration (FDA) allows the use of ionizing radiation to a dose up to 10 kGy for controlling foodborne pathogens and extending the self-life of foods. Recently X-rays, generated on absorption of high energy electrons in an appropriate metal target, have been used commercially for sterilization purposes. X-rays have the advantages of higher penetration power than E-beams and absence of harmful radioactive sources, such as Cobalt-60 or Cesium-137 associated with gamma-rays. That is why it has continued to receive attention as an attractive alternative to gamma-ray or E-beam irradiation. In this article, the potential of X-ray irradiation for controlling foodborne pathogens in various food products and necessary pre-requisite knowledge for the introduction of X-ray irradiation to the Korean food industry will be provided.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.388-393
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• 2015

This study aimed to investigate the therapeutic effect of rutin against whole-body ${\gamma}$-irradiation in BALB/c mice. BALB/c mice were randomly divided into four groups and exposed to 6 Gy ${\gamma}$-irradiation. One hour later, mice were orally administered rutin (50 and 100 mg/kg) for seven consecutive days. ${\gamma}$-Irradiation (6 Gy) resulted in cellular damage as manifested by elevated levels of plasma hepatic marker enzymes and lipid peroxidation in liver tissue, accompanied with decreased spleen and thymus indices, and white blood cell count. In addition, ${\gamma}$-irradiation significantly decreased the levels of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase and catalase. Rutin treatment significantly protected against ${\gamma}$-irradiation-induced cellular damage, which was evident by the improvement in the status of most of the investigated parameters. Therefore, rutin has beneficial effects against radiation-induced damage.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.338-344
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• 2001

The effect of gamma-irradiation on the microbiological and general qualities of Kanjang (fermented soy sauce, Korean type) and Shoyu (fermented soy sauce, Japanese type) was studied. Samples were prepared, irradiated at 5, 10 and 20 kGy, and then stored at $25^{\circ}C$ for 18 weeks. The results showed that the Bacillus spp. was inactivated by 3 log cycles with the irradiation dose of 10 kGy and the number of Bacillus cells that survived from 10 to 20 kGy of gamma irradiation was decreased gradually during storage. Yeasts and Lactobacillus were nearly eliminated at 5 to 10 kGy of irradiation. The $D_{10}$ values of Bacillus, yeast and Lactobacillus in Shoyu were 2.67 kGy, 0.81 kGy and 1.30 kGy, in Kanjang were 2.75 kGy, 0.99 kGy and 1.47 kGy, respectively. The general quality of gamma irradiated Shoyu and Kanjang, such as total nitrogen, amino nitrogen, protease activity and pH were more stable than that of control during storage periods. Decolorization was observed just after irradiation, but the color was recovered during storage. The sensory evaluations showed that irradiated samples were more acceptable. Therefore, it was considered that gamma irradiation was effective for maintaining better quality of Shoyu and Kanjang during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.723-727
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• 2002

Conformational changes of allivin, a major allergen protein in garlic, by gamma irradiation were observed. Allium solution (3.0 mg/mL in 0.01 M PBS, pH 7.4) and raw garlic were irradiated in a gamma irradiation facility to be absorbed with doses of 2.5, 5.0, 7.5 and 10.0 kGy. After irradiation, a half of irradiated allivin solution was filtered through 0.22 ${\mu}{\textrm}{m}$ filtration kit. UV spectrum and SDS-PAGE were used for observing the conformational changes of allivin by gamma irradiation. Turbidity of allivin solution was increased by optical observation, and the result was validated by the increase of absorbance at 660 m. Turbidity of irradiated and filtered allivin solution significantly (p<0.05) decreased, and the concentration of soluble protein in the solution decreased by increase of the dose. Aggregation among allivin molecules was observed by SDS-PAGE, but irradiated and filtered samples showed decrease of allivin with reducing aggregation trend. SDS-PAGE profiles of irradiated raw garlic were not different. Results indicate that gamma irradiation can decrease the allivin in solution state which may impact on allergenic reaction of garlic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1070-1075
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• 2006

Food materials for kimchi manufacturing were treated by ozone or gamma irradiation to reduce the number of contaminated microorganisms before the manufacturing of kimchi. Counts of total aerobic bacteria, yeast and mold were $10^6{\sim}10^7 and 10^3{\sim}10^4\;CFU/g$ in the food materials, respectively. After treatment with ozone $(3{\sim}6\;ppm), the total aerobic bacteria were reduced to 1 log cycle or more, in a dose-dependent manner. In comparison, gamma irradiation was superior to ozone treatment. Especially, irradiation of 5 kGy fully eliminated the yeast and mold attached in the food materials for kimchi manufacturing. The contents of ascorbic acid and total and reducing sugar were not affected by ozone or gamma irradiation. Taken together, it is suggested that microorganisms contaminated on materials for kimchi manufacturing could be substantially reduced by ozone (up to 6 ppm) and gamma irradiation (up to 5 kGy), without effect on the nutritional contents.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.335-342
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• 2011

The effects of gamma irradiation on the survival, development, fecundity, and sex ratio of the multicolored Asian ladybird beetle (Harmonia axyridis) were investigated. A dose of more than 50 Gy dose of irradiation on eggs completely inhibited hatch, and 1st and 3rd instar larva irradiated with over 40 Gy almost died. Adverse effects of gamma irradiation over 70 Gy were also observed in the survival and development of pupae and adults. Although irradiated individuals usually survived, they had longer periods of larval and pupal development than untreated individuals. Slight female-biased sex ratios were observed in some treatments. However, sex ratio differences soon equilibrated. Generally, inherited harmful effects of gamma irradiation were observed in F1 and F2 generations. Comet tail indicating DNA damage was showed in survival individuals exposed to gamma irradiation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.104-108
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• 2006

Effect of gamma irradiation on the softening of dried fernbrake at different moist-heating conditions was investigated. Dried fernbrake packaged in controlled atmosphere $(CO_2\;25\%,\;N_2\;75\%)$ was irradiated up to 7 kGy with $\gamma-ray$. Hardness of dried fernbrake was significantly decreased at the irradiation dose of above 5 kGy. Hardness of cooked fernbrake was significantly decreased with increasing irradiation dose level as well as heating temperature and time. $DT_{50}$ value (The heating time required to reach the $50\%$ reduction of hardness) for irradiated fernbrake was shortened according to dose level as well as heating temperature and heating time: $DT_{50}$ value of control: 23 min, 5 or 7 kGy: $2.2\~5.0$ min at $60^{\circ}C$. Also, the activation energy for softening of irradiated fernbrake ($1.85\~1.88$ kcal/mole for $5\~7kGy$) decreased compared to control (4.30 kcal/mole). Moisture content, swelling and rehydration rate of gamma irradiated fernbrake during moist heating increased according to the irradiation doses. Sensory results showed that scores of off-flavor and odor in irradiated fernbrake upto 7 kGy were not significantly different from control. Based on these results, gamma irradiation was effective for the reduction of cooking time and the activation energy for softening of dried fernbrake with increasing dose levels.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1128-1134
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• 2000

This study was carried out to evaluate quality properties of gamma-irradiated Kwamegi prepared from Cololabis seira semi-dried by cold sea wind. Edible portion of Kwamegi was prepared from whole body, vacuum-packaged, gamma-irradiated in the doses of 3 or 5 kGy, and stored at $5^{\circ}C$ for 60 days. Volatile basic nitrogen and trimethylamine contents were not different by gamma irradiation. During storage increase of those two compounds were inhibited depending upon the dose. Thiobarbituric acid values did not differ in all samples, regardless of irradiation and storage. The amount of total volatile compounds of Kwamegi decreased by irradiation. Rheological properties were not affected by irradiation and were maintained up to 60 day when the Kwamegi was irradiated at 5 kGy dose, but those of control was softened. Sensory evaluation had no differences in all samples immediately after irradiation. Sensory quality of Kwamegi irradiated were organoleptically adequate, however that of control was deteriorated. In conclusion, these results indicate that gamma irradiation technique can be used to maintain the quality of Kwamegi.