• 한국식품영양과학회지
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• 제31권2호
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• pp.246-250
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• 2002

감마선 조사가 왕겨, 미강, 맥강의 항산화능에 미치는 영향을 조사하기 위하여 4.2 kGy/h의 속도로 각각 5, 10, 15, 20 kGy를 조산한 후, 메탄올 추출물을 제조하여 항산화능의 변화를 측정하였다. 감마선을 조사하지 않은 시료의 총 페놀함량을 측정한 결과, 왕겨가 0.873 mM, 미강이 0.643 mM, 맥강이 0.377 mM로 측정되었으며, 감마선 조사에 따른 총 페놀 함량은 조사선량에 상관없이 일정하게 유지되었다. 전자공여능의 측정결과 감마선을 조사하지 않은 왕겨, 미강, 맥강에서 모두 비슷한 활성을 보였으며, 감마선을 조사한 경우에도 모든 시료에서 조사선량에 따른 유의적인 변화를 나타내지 않았다. TBARS분석에서는 감마선을 조사하지 않은 왕겨와 미강 추출물이 맥강 추출물보다 지질 과산화 억제력이 높았으며, 감마선 조사시에도 왕겨와 미강은 활성이 유지 또는 보유되었으나 맥강은 조사선량이 높을수록 지질의 산화 억제력이 상당히 감소되었다. 따라서 왕겨, 미강, 맥강의 페놀성분과 전자공여능에 관여하는 성분이 감마선에 매우 안정하며, 지질 과산화 억제능에 관여하는 성분은 왕겨와 미강의 경우에는 감마선에 안정하지만 맥강의 경우 불안정하였다.

• Toxicological Research
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• 제13권1_2호
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• pp.55-60
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• 1997

Gamma irradiation was applied to Angelicae gigantis radix and Aloe to improve their hygienic quality. The effective dose of irradiation was 7 kGy in Angelicae gigantis radlx and 5 kGy in Aloe for the sterilization of all contaminated microorganisms tested. After 8 months of storage at room temperature, no growth of microorganisms was observed in the irradiated products. The safety of these products were evaluated by Salmonella typhimurium reversion assay and in vivo micronucleus assay using mouse bone marrow cells. They were negative in the bacterial reversion assay with S. typhimurium TA 98, TA100, TA1535 and TA1537. In the in vivo mouse micronucleus assay, they did not show any clastogenic effect at all doses tested. These results indicate that the gamma irradiation of Angelicae gigantis radix at 12 kGy and of Aloe at 10 kGy have no genotoxic effects under these experimental conditions.

• 한국식품저장유통학회지
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• 제6권1호
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• pp.16-22
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• 1999

Microbial populations (total bacteria, lactic acid bacteria and coliforms), TBA, VBN and POV were investigated for evaluating the shelf life of pork loins gamma-irradiated at doses of 1, 3, 5 and 10 kGy with air-contained and vacuum-packaged methods. The initial microbial populations decreased with gamma irradiation depending upon the dose and microorganisms in the vacuum-packaged samples were inhibited more than those in the air-contained samples. POV, TBA and VBN values were higher in the air-contained samples than in the vacuum-packaged samples. In conclusion, the combination of gamma-irradiation and vacuum-packaging could extend the shelf life of chilled pork loin.

• Parasites, Hosts and Diseases
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• 제41권1호
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• pp.41-45
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• 2003

Effects of gamma irradiation on the worm survival and chromosomal aberration of Clonorchis sinensis were studied. The metacercariae irradiated with various amounts of gamma radiation (ranging from 5 Gy to 50 Gy) were fed to rats, and the effects were compared with those of non-irradiated controls. Recovery rates of adult worms in irradiated groups were reduced gradually as increasing of the irradiation doses. No worm was recovered from rats which were fed with 50 Gy irradiated metacercariae. The chromosome number was 2n = 56 in all worms from all experimental groups. However, the groups irradiated with 20 Gy, 25 Gy or 30 Gy showed variations in the chromosome number, depending on different cells in the same individual. Radiation doses used in this study did not appear to induce chromosome aberrations, however, irradiation with 30 Gy showed slightly reduced chromosome size.

• 한국안전학회지
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• 제19권3호
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• pp.26-31
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• 2004

The radiation-induced changes taking place in poly(vinylidene fluoride) (PVDF) exposed to $^{60}Co$ $\gamma-ray$ irradiation were investigated in correlation with the applied doses. Samples were irradiated in air at room temperature by $^{60}Co$ $\gamma-ray$ to doses in the range of 200 to 1000kGy. Various properties of the irradiated PVDF were studied using FTIR, differential scanning calorimetry (DSC), gel fraction and elongation. $^{60}Co\gamma-ray$ irradiation was found to induce changes in chemical, thermal, mechanical and structural properties of PVDF and such changes vary depending on the radiation dose.

• 한국식품영양과학회지
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• 제28권4호
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• pp.954-957
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• 1999

The changes in L ascorbic acid content by processing treatments; gamma irradiation, heating and microwave were investigated using high performance liquid chromatography. The content of L ascorbic acid in standard solutions and citrus fruits decreased from 27.4 to 44.9% and from 6.9 to 21.9%, re spectively, by gamma irradiation doses in the range of 1 to 10 kGy. By heating treatments, L ascorbic acids in standard solutions and citrus fruits were destroyed 22.5 to 36.8% and 4.5 to 18.1%, respectively. By microwave treatment, L ascorbic acid content also decreased from 23.1 to 47.4% and from 6.5 to 22.6%, respectively.

• 방사선산업학회지
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• 제4권3호
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• pp.215-219
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• 2010

We have subjected to gamma-irradiation to citrus buds and then grafted onto mature citrus tree. Mutant citrus branch lines have been induced. As a result of first selection, we found the several mutant lines showing interesting phenotypes such as higher sugar content. We have selected several branches showing good qualities such as higher sweetness and/or lower acidity. Some branch lines showed over $13^{\circ}Brix$ sugar content and below 0.9% acidity. Other mutant branch lines showed the changes of shape, size, peel thickness, and fiber contents or distribution of fruits. The results suggest that gamma-irradiation is an effective tool for induction of citrus mutant lines.

• 방사선산업학회지
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• 제7권1호
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• pp.51-54
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• 2013

Chitosan is a useful natural polymer material in many application fields such as biomaterials, water-treatment, agriculture, medication, and food science. However, the poor solubility limits its application. In this study, the effects of radiation on chitosan were investigated using gamma ray and electron beam irradiation. The chemical structure and molecular weight analysis show similar degradation effects of chitosan powder in both gamma ray and electron beam irradiation. However, the radiation irradiated chitosan in $H_2O$ has a lower molecular weight, since the hydroxyl radicals attack the glycosidic bonds. This effect is more clearly shown in the electron beam irradiation results.

• 한국수산과학회지
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• 제54권6호
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• pp.982-988
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• 2021

Gamma irradiation is one of the simple methods used to induce mutagenesis. Therefore, it is widely used for the development of breeding lineages of plants and algae. In this study, it was developed a new variety of Pyropia yezoensis using gamma irradiation. It was applied a dose of 1 kGy and named the developed mutant Py1k. The blade with width of the mutant was narrower and the blade length was longer than those of the wild type. To further investigate the mutant, it was analyzed the nutrient composition and antioxidant activity. In comparison to those in the wild type, it was found a higher amino acid composition and marginally increased antioxidant activity in Py1k. Based on these results, it was suggests that our protocol can be utilized to develop Pyropia species with improved nutritional quality through gamma irradiation.

• 한국식품영양학회지
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• 제23권1호
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• pp.84-87
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• 2010

Effects of gamma irradiation on microbiological changes of Gorosoe sap were characterized during a post-irradiation storage at $4^{\circ}C$. The aseptically collected sap was irradiated and stored at $4^{\circ}C$ for 0 to 60 days and analysed for standard plate counts and 16S rDNA. There were significant differences in the total number of colony forming units(CFUs) of bacteria between irradiated and non-irradiated control sap. Bacteria of non-irradiated sap were present at levels of $1.5{\times}10^4{\sim}2.3{\times}10^8\;CFU/m{\ell}$, whereas no viable microbial cells were detected in sap after 10 kGy of irradiation during storage. According to the 16S rDNA sequence analysis, bacterial community structures decrease with time and the most abundant strain was Pseudomonas species. Our results suggested that gamma irradiation can be used to enhance the shelf-life of Gorosoe sap.