• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.191-195
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• 2003

We investigated the effects of gamma irradiation on the microbiological, chemical and sensory qualities of bulgogi, a traditional Korean meat product. Gamma irradiation reduced the number of coliform bacteria and bacterial colonies counted in Salmonella-Shigella selective agar to a non-detectable level. Thermophillic microorganisms (mainly Bacillus spp.) in bolgogi refrigerated for 20 days were also significantly reduced by 3 log cycles by 2.5 to 7.5 kGy of irradiation, compared to the control. Electron donating ability and shear force of ready-to-cook bulgogi was not significantly affected by gamma irradiation. Irradiation increased the 2-thiobarbituric acid reactive substances (TBARS) value. The irradiated, raw, ready-to-cook bulgogi had significantly higher scores in color and appearance than those of non-irradiated controls from sensory evaluation. The overall acceptance of cooked bulgogi had higher scores in non-irradiated or 2.5 kGy-irradiated bulgogi than the 5.0- or 7.5-kGy irradiated counterparts. In conclusion, irradiation at 2.5 kGy is recommended as a method to improve shelf-life, safety, and to achieve acceptable quality of ready-to-cook bulgogi without any adverse changes in the sensory characteristics.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.514-515
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• 2008

Low level laser therapy has various therapy effects. This paper performed the basic study for developing the Low Level Laser Therapy Equipment for medical treatment. The apparatus has been fabricated using the laser diode and microprocessor unit. This equipment was fabricated using a micro-controller and a laser diode, and designed to enable us to control light time, frequency and so on. In this study, the designed device was used irradiation to find out how 850 nm laser diode affected the cell proliferation of RAT bone-marrow cells. Experiment was performed to irradiation group and non-irradiation group for Rat bone marrow cells. MTT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590 nm transmittance of micro plate reader. As a result, the cell increase of Rat bone marrow cells was verified in irradiation group as compared to non-irradiation group. The fact that specific wavelength irradiation has an effect on cell vitality and proliferation is known through this study.

• 한국의류산업학회지
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• 제15권3호
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• pp.430-436
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• 2013

The purpose of this study investigates the effects of electron beam(EB) irradiation on the chemical and morphological properties of Hansan ramie fiber. Hansan ramie fibers were irradiated with electron beam doses of 0, 1, 3, 5 and 10kGy. The effect of electron beam irradiation on the chemical components of fibers as well as the surface chemical and morphological properties were investigated using chemical component analysis methods based on TAPPI standards, XPS, and SEM. The results indicate that the surface layers can be removed under suitable EB irradiation doses. Alcohol-benzene extraction and lignin content increases gradually with an increase in EB irradiation and reaching a maximum at an EB dose of 3kGy, and decreases at 10kGy. The surface chemical changes measured by XPS corresponded to the chemical composition analysis results. The C1 peak and the O/C ratio decreased with the removal of the multi-layer and primary layer by EB irradiation. The SEM images show the inter-fibrillar structure etched by EB irradiation up to 5kGy. At 10kGy, the surface structure of the ramie fiber shows highly aligned and distinctive striations in a longitudinal direction. The removal of these exterior layers of the fiber was confirmed by changes in surface morphology as observed in SEM images.

• Preventive Nutrition and Food Science
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• 제8권1호
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• pp.85-88
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• 2003

Effects of irradiation on color removal, tyrosinase inhibition, xanthine oxidase inhibition and nitrite scavenging capacity of Lonicera japonica extracts were evaluated. Lonicera japonica extracts were irradiated at 10, 20, and 30 kGy. Hunter color $L^{*}$- and $a^{*}$-values increased but $b^{*}$-values decreased dose-dependently following irradiation. The extracts were potent inhibitors of tyrosinase and xanthine oxidase. Tyrosinase inhibition was higher in the irradiated sample than non-irradiated, and subsequently increased with increasing irradiation doses. The extracts had a higher inhibitory effect against xanthine oxidase, and the effect was not changed by irradiation. Nitrite scavenging capacity was the highest in the extract at pH 1.2, and was not significantly affected by irradiation. These results indicate that gamma irradiation may not influence the biological activities of Lonicera japonica extracts when irradiated up to 30 kGy. Furthermore, color of the extracts can be improved to have improved applicability for the food and cosmetic industries without any adverse change in biological functions.ons.s.

• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.16-22
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• 1996

Amino acids and ribonucleotides were measured for boiled-dried anchovy to determine the effect of 5 kGy γ-irradiation on its quality stability during storage at ambient and cooling (5∼10℃) temperatures for 12 months in a laminated-film package(Polyethylene 10㎛). The anchovy samples contained about 55%(d.b) of total amino acids and about 1%(d.b) of free amino acids. Although there found a significant change(p<0.01) in the content of leucine and lysine immediately sfter irradiation, the overall content of toral amino acids was little changed in stored anchovy even six months after irradiation at cooling conditions. γ-Irradiation caused a significant reduction(p<0.01) in the total content of free amino acids, showing a similar tendency by storage conditions. However, the ribonucleotides. which were 12.00mg/g(d.b) in inosine-5'-monophosphate and 0.38mg/g(d.b) in guanosine-5'-monophospate, were resistant to 5kGy-irradiation. With the lapse of storage time, it was also shown that storage temperature was more influential than irradiation on the contents of amino acids and taste compounds of dried anchovy.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.89-95
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• 1997

The comparative effects of gamma irradiation an ozone treatment on the microbiological and physicochemical qualities were investigated for the improvement of hygienic quality of aloe powder and bee pollen. Gamma irradiation at 7.5~10kGy could reduce total aerobic bacteria, molds and coliforms below detection levels, but ozone treatment up to 18 ppm for 8hr was not sufficient to eliminate the microorganisms from aloe powder and bee pollen. The physicochemical properties such as fatty acid an amino acid compositions, mineral content, TBA value, barbaloin and pigment contents were not significantly changed by gamma irradiation, whereas ozone treatment caused significant changes in fatty acid composition, lipid oxidation and destruction of barbaloin and natural pigments.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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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.

• Preventive Nutrition and Food Science
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• 제1권2호
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• pp.262-268
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• 1996

In Korea, the health authorities and food industry emphasize the need of sanitary food production, which in mainly resulted from the recent growing of consumer's interest in the safety of food. For the reason, development of a new alternative technology to chemicals, currently used for decontamination and disinfestation, has become and urgent task in the domestic and worldwide food industry. Furthermore, the improvement of quality and manufacturing process of processed food is a requisite for winning the competition in export fields. Irradiation technology being practically applicable in the food industry has been well established on the basis of more than 40 years of R&D work in the fields of the increasing availability of food-stuffs, sanitary food production and quarantine treatment in the food trade. The wholesomeness of irradiation foods has been officially approved in 38 countries, of which 30 countries are commercially utilizing food irradiation technology. The first commercial irradiator in Korea(18.5PBq:500k{TEX}$Ci^{60}${/TEX} Co, max. cap; 4MCi) was established at Yeoju-gur, Kyung Ki-do with the technical assistance of Korea Atomic Energy Research Institute in June 1987. As of 1996, thirteen irradiated food groups (over 25 items)have been domestically approved for human consumption and an industrial irradiation facility is also available. However, the domestically approved for human consumption and an industrial irradiation facility is also available. However, the promotion of consumer acceptance to toward ir-radiated foods is considered as a confronted subject to be studied for a commercial utilization.

• Journal of Periodontal and Implant Science
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• 제26권3호
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• pp.715-724
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• 1996

This study was performed to identify the proliferation and to measure the alteration of alkaline phosphatase activity in human gingival fibroblasts cultured. For the present study, the authors cultured the human gingival fibroblasts oriented from the sound interdental gingiva, and used third passage. It was used methyl $[^3H]$ Thymidine to identify the proliferation in human gingival fibroblasts and used 410nm of the spectrophotometer to measure the alteration of the alkaline phosphatase activity in human gingival fibroblasts. The results were as follows: 1. There was a statistically significant increase in the proliferation of gingival fibroblasts following low level laser irradiation at 24 hour(p<0.05). 2. There was a statistically significant increase in activity of alkaline phosphatase compared to control group at 5-day laser irradiation after in laser irradiation groups(p<0.05). And there was a statistically significant increase in activity of alkaline phosphatase compared to control group at 7-day laser irradiation after in the I-minute laser irradiation group(p<0.05), but there was a statistically significant decrease in activity of alkaline phosphatase compared to 1minute laser irradiation group at 7-day laser irradiation in the 2-minute laser irradiation group after(p<0.05). The results, within the limits of the present experiments, suggest that, the low level laser irradiation accelerates the proliferation of gingival fibroblasts and alters the alkaline phosphatase activity until the restricted period.

• Journal of Animal Science and Technology
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• 제51권1호
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• pp.75-80
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• 2009

Composition changes of swine manure and the effects on MAP ($MgNH_4PO_46H_2O$) crystallization by microwave irradiation were examined. The concentration of ${PO_4}^{3-}$ was increased within a fixed period of time and then decreased, but $NH_4$-N was reduced continuously during microwave irradiation. Concentration of ${PO_4}^{3-}$ was started to reduce just from the point of foam formation during microwave irradiation, and the temperature at that time was always $49^{\circ}C$ irrespectively to microwave irradiation rate. Inorganic carbon was reduced with microwave irradiation, but soluble organic carbon (TOCs) was increased proportionally. Crystallization rate under conditions of non-microwave irradiation, irradiation up to $93^{\circ}C$ and $48^{\circ}C$ was 87.8%, 87.3% and 98.5%, respectively, showing 10% enhancement when irradiated up to $48^{\circ}C$. However, removal efficiency of ammonia nitrogen was proportional to the microwave irradiation rate or duration, obtaining 2.5%, 4.5% and 10.2%, respectively. Based on these results, it would be a useful strategy to irradiate microwave up to $49^{\circ}C$ to enhance MAP crystallization rate by changing the ionic pattern of nutrients in the manure. Meanwhile, provision of enough microwave irradiation rate might be needed to achieve high $NH_4$-N removal.