• Journal of Sericultural and Entomological Science
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• v.10
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• pp.63-66
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• 1969

As a result of analyzing the change of material substance of all sorts biochemically and comparing the control with ${\gamma}$-ray irradiation (800r, 400 min), incubating the silkworm egges (bombyx. mori. L.) as the objective in the process of growth of embryo shortly before hatching, the following conclusion has been found. 1. Glucose has shown the increase of 281.2 mg/g in control during the pigment stage and it has shown the increase of 179.6 mg/g in ${\gamma}$-ray irradiation during the same period. The difference in quantity between the former and the latter is due to the fact that the growth of embryo has been influenced by the radio active. Glucose has changed with phosphorus the other way round. 2. Control organic phosphorus has shown the increase of 5.23 mg/g during the Byong B or KI A in which organ and tissue in the embryo has been formed. Organic phosphorus in ${\gamma}$-ray irradiation has shown the increase of 5.73 mg/g during KI B. Inorganic Phosphorus has shown only a little change in the control and ${\gamma}$-ray irradiation. The phosphorus in both has shown a little quantity in the ${\gamma}$-ray irradiation in early period of incubation. After the Ki A embryo, it has increased rapidly and it has increased till the hatching more continually than in control. The about results of the research will be helpful and instructive to the betterment and improvement, breeding and management of animals and plants.

• Food Science of Animal Resources
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• v.18 no.3
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• pp.232-239
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• 1998

This experiment was conducted to investigate radurization effects of gamma ray and electron beam irradiation at 1.5 and 3.0 kGy on beef steaks during 8 days of storage at 5$^{\circ}C$. Total bacteria count, psychrotrophs, mesophiles and thermophiles were analyzed at 2 days intervals. Nonirradiated beef steak was used a scontrol Total bacteria counts, psychrotrophs, mesophiles and thermophiles of the control samples showed 3.03∼4.72 logCFU / g at 0 day and increased to 7.67∼10.90 logCFU / g during 8 days storage except thermophiles. Total bacteria counts, psychrotrophs and mesophiles of beef steaks at 8 days were significantly (p＜0.05) decreased to 3.61∼5.43 logCFU / g by gamma ray and to 3.83∼7.02 logCFU / g by electron beam irradiation at 1.5 and 3.0 kGy. Thermophiles of all irradiated samples at any dose were not detectable through 8 days storage. These results suggested that both gamma ray and electron beam irradiation were effective to extend lag phase of bacterial growth of refrigerated beef. Gamma ray irradiation was better than electron beam irradiation in terms of radurization effects of beef.

• KSBB Journal
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• v.26 no.2
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• pp.177-181
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• 2011

This study was conducted to investigate the effects of gamma irradiation on the change of volatile flavor compounds of raw oyster and its cooking drips using headspace methods. Major volatile flavor compounds of the raw oyster were identified as methylthiomethane and 1,5-hexadiene. When the raw oyster was irradiated at the dose of 5 kGy, 1-pentane was newly detected. On the other hand, 9 compounds including N-methoxyformaldehyde were identified as the major volatile compounds of cooking drips from oyster. Among them, N-methoxyformaldehyde contents in cooking drip was decreased by the gamma irradiation. By the gamma irradiation above 30 kGy, new heterocyclic compounds was found in oyster cooking drips. Therefore, the amount of volatile flavor compounds in the raw oyster and cooking drips were changed by gamma irradiation, and these results could be potentially used in the seasoning industry.

• Korean Journal of Microbiology
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• v.6 no.2
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• pp.54-62
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• 1968

The effect of gamma-ray on yeast cells Sacch. cerevisiae, and the leakage of cellular constituents such as carbohydrates, ribose, amino acids, inorganic phosphates and organic phosphates have been studied. The samples of yeast cells washed throughly and starved intensively, radiation effects were compared with those of control (un-starved), the irradiation dose rates are in the range from 24 Kr. up. to 480, Kr. The loss of 260m$\mu$. absorbing material, are also observed. Mechanisms of membrane damage by gamma-irradiation are discussed corelating to permeability changes and loss of substances, then active and passive transport process are also under considerations in discussion. The experimental results are as follows, 1. Carbohydrates of yeast cell leak out by gamma-irradiation, and amounts of loss increase proportionally as the increasing of radiation dose, curve of carbohydrates loss in starved cells is parallel with those of non-starved cells. 2. Ribose leak out less than that of carbohydrate from irradiated cell, the dose response curve of loss is straight and proportional to the increasing of radiation doses, slope of the curve is much lower than of carbohydrates. 3. Amino acids also leak out and the curve of losses to radiation is not proportional, it is revealed that there are little losses from yeast at lower doses of irradiation. 4. The losses of inorganic phosphates increase unproportionally to the increasing of irradiation doses, there are little leakage at the lower doses of irradiation. The losses of organic phosphates increase proportionally to the increasing of irradiation doses, and the amount of losses are much more than that of inorganic phosphate at lower doses of irradiation. 5. Leakage from irradiated yeast cells was shown to be due to passive transport process not an energy requiring process of ion transport. 6. Loss of 260 m$\mu$. absorbing material is little more than that of control yeast by the gamma-irradiation dose of 120K.r. and 240K.r.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1035-1041
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• 2000

Gamma irradiation was used to improve sanitation and quality of salted and fermented anchovy sauce. For commercial production, comparison with currently using sterilization methods, such as micro-filtration and heat treatment were also conducted. Control was prepared without irradiation and sterilization process. Microbiological, physiochemical, and sensory qualities were analyzed to observe the Quality changes during the storage. Irradiation at 5 kGy or above and micro-filtration process completely eliminated microorganisms detected in this study As irradiation dose increased, the color appeared brighter and irradiation at 5 kGy or above showed similar color L-value to that of sample treated with microfiltration. The color L, a, b-value of heat-treated sample always showed lower. The pH, salinity, and viscosity were sustained during storage. From the results of sensory evaluation, the samples treated with gamma irradiation and microfiltration obtained better scores than control or heat-sterilized. Gamma irradiation to salted and fermented anchovy sauce presented the best quality products among different sterilizing methods, especially at 5 kGy dose. Therefore, gamma irradiation can be successfully applied to commercial large scale production as a new sanitation technology with improved quality.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.523-531
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• 2008

Radiotherapy is currently applied in the treatment of human cancers. We studied whether genistein would enhance the radiosensitivity and explored its precise molecular mechanism in cervical cancer cells. After co-treatment with genistein and irradiation, the viability, cell cycle analysis, and apoptosis signaling cascades were elucidated in CaSki cells. The viability was decreased by co-treatment with genistein and irradiation compared with irradiation treatment alone. Treatment with only ${\gamma}$-irradiation led to cell cycle arrest at the $G_1$ phase. On the other hand, co-treatment with genistein and ${\gamma}$-irradiation caused a decrease in the $G_1$ phase and a concomitant increase up to 56% in the number of $G_2$ phase. In addition, co-treatment increased the expression of p53 and p21, and Cdc2-tyr-15-p, supporting the occurrence of $G_2/M$ arrest. In general, apoptosis signaling cascades were activated by the following events: release of cytochrome c, upregulation of Bax, down regulation of Bcl-2, and activation of caspase-3 and -8 in the treatment of genistein and irradiation. Apparently, co-treatment downregulated the transcripts of E6*I, E6*II, and E7. Genistein also stimulated irradiation-induced intracellular reactive oxygene, species (ROS) production, and co-treatment-induced apoptosis was inhibited by the antioxidant N-acetylcysteine, suggesting that apoptosis has occurred through the increase in ROS by genistein and ${\gamma}$-irradiation in cervical cancer cells. Gamma-irradiation increased cyclooxygenase-1 (COX-2) expression, whereas the combination with genistein and ${\gamma}$-irradiation almost completely prevented irradiation-induced COX-2 expression and $PGE_2$ production. Co-treatment with genistein and ${\gamma}$-irradiation inhibited proliferation through $G_2/M$ arrest and induced apoptosis via ROS modulation in the CaSki cancer cells.

• Toxicological Research
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• v.20 no.1
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• pp.31-36
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• 2004

Against environmental stress, ceruloplasmin which is a plasma protein, are believed to play central roles in antioxidant- or peroxidase-activity in blood stream to remove free radicals, which may be caused by exposing of $\gamma$-irradiation. In human U-937 cells exposed to $\gamma$-irradiation, the levels of mRNA in ceruloplasmin gene were measured on 0, 4, 12, 24 hr after exposing by using comparative RT-PCR (Reverse transcriptase-polymerase chain reaction) which was achieved to compare with house keeping genes such as $\beta$-actin and hprt. After $\gamma$-irradiation of 100 rads or 200 rads, the total quantities of RNA were increased as dose and time dependent manner. On the contrary, the variation of mRNA expression in ceruloplasmin was not found until 4 hr after irradiation. After 12 hr and 24 hr of irradiation, the levels of mRNA in ceruloplasmin were significantly increased as dose and time dependent manner than un-exposed cells.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.135.1-135
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• 2003

To elucidate the effect of gamma-irradiation on the molecular properties of hemoglobin, the secondary, tertiary structure, and the molecular weight size of the protein were examined after irradiation at 0.5, 1, 5, and 10 kGy. Gamma-irradiation of hemoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid decreased the degradation and aggregation of proteins by scavenging oxygen radicals that were produced by irradiation. A circular dichroism study showed that irradiation decreased the helical content of hemoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation decreased the emission intensity that was excited at 280 nm.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1051-1057
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• 1999

The effects of gamma irradiation on taste compounds of low salted and fermented squid were investig ated. Salted and fermented squid products were prepared with salt concentrations of 5%, 10%, and 20% and was fermented at 15oC and 25oC after gamma irradiation with a dosage of 2.5~10 kGy. Amino nitrogen (AN), volatile basic nitrogen(VBN), trimethylamine(TMA), and hypoxanthine(Hx) contents were examined during the fermentation periods. Results showed that gamma irradiation had no effect on the initial con tents of AN, VBN, TMA, and Hx compared with non irradiated salted and fermented squid. During the fermentation periods, these contents rapidly increased in accordance with the decrease in NaCl concen tration and irradiation dose, and the increase in fermentation temperature. Specifically, the taste compounds of salted and fermented squid prepared with a NaCl concentration of 10% and an irradiation dose of 10 kGy maintained the appropriate level for the fermentation period at 15oC.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.69-78
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• 1967

Kim, Jong Hyup, (Div. of Biology, Atomic Energy Research Institute.) Studies on the Cellular Metabolism in Microorganisms as influenced by Gamma-irradiation(II). On respiration rate and dehydrogenase activity of yeast cells irradiated by gamma ray from cobalt-60. 1. Oxygen uptake rate of the gamma irraiated yeast cells had been measured with Warburg's manometer, and the $O_{2}$-uptake was compared with those of normal cells. The rate of endogetious respiration increases in its $O_2$-uptake at 150, 000 rentgen dose, and at higher rentoen doses it was decreased. Exogenous respiration begin to decrease in its O_2$-uptake at 5, 000r. doses of irradiation, further decrease with increasing of doses unproportionally. 2. It appears that plasma-membrane and nuclear membrane of yeast cells have changed and denatured by gamma-irradiation, as exogenous respiration of glucose had been decreased at a dose of 200, 000r's irradiation. 3. The activity of glucose, alcoholic, lactic, succinic and glutamic deliydrogenase (G.D.H., A.D.H., L.D.H., S.D.11., and GL.D.H.) in the gamma irradaited cells had been assayed by T.T.C.(Triphenyl tetrazolium chloride) method and spectrophotometry, the obtained results were compared with those of normal cells. 4. At a dose of and 10, 000 rentgens' irradiation of gamma ray, the activty of each debydrogenase (G.D.H., A.D.H., L.D.H., ) shows a sharp and highest peak in optical absorbalicy, but each abtivity of S.D.H and Gl.D.H shows its' maximum peak at a dose of 30, 000r. 5. The curve of each dehydrogenase activity was found to be rhythmical according to dose-rate of gamma irradiation. 6. Comparing with activity of debydrogenase each other, the maximum peak in optical absorbency can be arranged according to order as follows; glucose > alcoholoic > lactic > glutamic > succinic, this order is identical to the order of breakdown utility in respiration of normal yeast cells. 7. The activity of dehydrogenase experimented exhibit a resistance against gamma irradiation at lethal dose of cells, and the activity of dehydrogenase are found to be much resistant than those of respiratory system. We may assume that the membrane substrate of mitochondria or cytoplasm had been destructed by gamma-irradiation much more than that of dehydronase system.