• Journal of agriculture & life science
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• v.43 no.3
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• pp.27-34
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• 2009

Green tea was prepared by soaking 1.5 g of green tea leaves into 100 mL of distilled water at $75^{\circ}C$ for 5 min. The green tea was stored at three different conditions - (A) green tea was stored at not-artificially excluding natural light condition, at natural air condition, and without addition of vitamin C; (B) green tea was stored at artificially excluding natural light condition by wrapping a vial with aluminium foil, at nitrogen filling up condition, and with addition of 30 mg/100 mL of vitamin C; and (C) green tea was stored at artificially excluding natural light condition by wrapping a vial with aluminium foil, at nitrogen filling up condition, and without addition of vitamin C. After 28 days of storage at $4^{\circ}C$, the chemical quality of the green tea was evaluated. Total phenolic contents of (A), (B), and (C) green tea decreased to 71.50, 73.88 and 75.07%, respectively, after storing for 28 days compared to those of beginning state. DPPH radical scavenging activities of (A), (B), and (C) green tea were 87.87, 92.93 and 88.39%, respectively. Epigallocatechin gallate (EGCG), the main active compounds of green tea, contents of (A), (B), and (C) green tea were 130.61, 136.47 and 4.34%, respectively. The results indicated that light, air condition, and vitamin C were significantly important to the chemical quality of green tea during storage.

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.511-521
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• 2019

The purpose of this study was to investigate the inhibitory effect of enzyme activity and anti-proliferation of human cancer cell lines (HCT 116, NCI-H460 and MCF-7) of peanut skin depending on cultivars (Arachis hypogaea L. cv. K-Ol, cv. Sinpalkwang, cv. Daan, cv. Heuksaeng) and extraction solvent. Peanut skin was extracted with 80% ethanol, 80% methanol, 80% acetone, and distilled water, followed by analysis of the enzyme inhibitory activity and anticancer activity. Methanol extract of Daan cultivar most effectively inhibited ${\alpha}$-gluosidase (65.08%, 0.025 mg/mL), tyrosinase (82.49%, 2 mg/mL) and ACE (73.61%, 10 mg/mL). The inhibitory effect of peanut skin extracts on colon cancer cell (HCT-116), lung cancer cell (NCI-H460) and breast cancer cell (MCF-7) growth were investigate using MTT assay. The highest anti-proliferation of cancer cell line of peanut skin extracts was observed in the methanol extract of Daan cultivar. The cell viability on HCT 116, NCI-H460 and MCF-7 cell lines of methanol extracts from peanut skin of Daan cultivar was 48.13%, 41.03%, and 36.02% at $200{\mu}g/mL$, respectively. These results suggest that peanut skin extracts may mediate physiological activity, and provide valuable information for the use of peanut byproduct as a functional food material.

• Journal of Adhesion and Interface
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• v.4 no.1
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• pp.28-34
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• 2003

Steel tire cords were subjected to plasma polymerization coating of acetylene in order to enhance the adhesion to rubber compounds. Plasma polymerization coating was varied to plasma polymerization coating of acetylene, argon plasma etching+plasma polymerization, or argon plasma. etching+plasma polymerization with Ar carrier gas. Adhesion was evaluated via TCAT samples and compared to those with brass coated tire cord. For durability study, plasma polymer cooled tire cords were aged in lab atmosphere for 1, 3, 5, 10 or 15 days, while TCAT specimens prepared with plasma polymer coated tire cords were aged in distilled water, 10% NaCl solution or $100^{\circ}C$ oven for 1, 2, 3 or 4 weeks. After testing, failure surfaces were analyzed with SEM/EDX. Among the treatments, the highest adhesion was obtained by Ar etching+acetylene plasma. polymerization coating with Ar carrier gas, providing almost same pull-out force as the brass coated tire cords. Upon the aging of the tire cords in the lab atmosphere, brass coated tire cords provided better adhesion than plasma polymer coated tire cords, while the TCAT samples with plasma polymer coated tire cords exhibited similar or slightly superior durability to those with brass coated tire cords.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.4
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• pp.1-11
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• 2012

Objectives: Osteoporosis, which occurs after menopause, is a kind of metabolic bone disorder. It develops when the bone mass begins to decrease radically, and its main symptoms are bone fracture and height-shortening. This thesis aims at what effects the Cuscutae Semen Extract(CSE) has on the prevention of osteoporosis in SD-rat that is caused by ovariectomy. Methods: The 24 female white rats, after removing their ovaries, were divided into the Normals, the Control group, and the CSE administrated group. For the next 8 weeks, distilled water to the normals and the control, and the CSE(45.9 mg/100 g) to the CSE administrated group were given in the mouths of them. After 8 weeks the rats were sacrificed. Weight, albumin, aspartate aminotransferase, alanine aminotransferase, total-cholesterol, triglyceride, phosphorus, calcium, tetraiodothyronine, estradiol, the weight of the femur, the amount of tibia ash, the area of trabecular bone, and the thickness of trabecular bone were measured. Results: The serum analysis shows that the calcium and phosphorous of the CSE administrated group significantly increased compared to that of the control group. Aspartate aminotransferase, alkalinephosphatase, total cholesterol, tetraiodothyronine of CSE group were decreased, but not so significant. Albumin, alanine aminotransferase, triglyceride and estradiol of the group showed the tendency to increase, but the significance wasn't admitted. Regarding the variation of bone, the femur weight and the ash content of tibia, CSE group was more increased than the control group but the significance wasn't admitted. The histological observation shows that the trabecular thickness was more increased than the control group, and trabecular area increased significantly compared to those of the control group. The number of osteoclast and osteoblast area of the CSE groups decreased significantly compared to those of the control group. Conclusions: From the result of the above study, CSE should be effective for the osteoporosis cure and precaution and deeper study through bedside and clinical demonstration is much needed from now on.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.1
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• pp.35-52
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• 2016

Objectives :The purpose of this study was to investigate the effect on factors related the expression of aquaporins (AQP) and milk production after administration of Boheotang-gagam in lactating mice. Methods: The SKH-1 mice were randomly allocated to the control group which was administered with distilled water for two weeks after the parturition and the experimental groups such as, lactating+400G group (L400G) which was administered with Boheotang-gagam 400 mg/day, lactating+600G group (L600G) which was administered with 600 mg/day for two weeks after the parturition, and 400G+lactating+400G group (400G-L400G) which was administered with 400 mg/day for 3 weeks starting one week prior to parturition for experiment (n=6 per group). Results: 1. With regard to the immunohistochemical staining reaction for AQP1, AQP3, and AQP5, stronger immune response was also showed in mammary gland in all experimental groups as compared to the control group. AQP1 showed stronger immune response in the capillaries and venules which were located around the interlobular duct, while stronger immune response of AQP3 and AQP5 showed in the secretory alveolar epithelia and intralobular and interlobular ductal epithelial cells. 2. In the western blot, L400G group showed the most increased expression followed by L600G and then 400G-L400G group in AQP1. In AQP3, the order of expression density was observed as L600G, 400G-L400G and L400G group. Lastly, in AQP5, L400G group presented the most increased expression followed by L600G and 400G-L400G group. Conclusions: Boheotang-gagam would have the effect of increasing the lactation of mice after the birth by increasing the prolactin level and adjusting the expression of AQPs and prolactin receptor in the mammary glands.

• Nuclear Engineering and Technology
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• v.18 no.4
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• pp.273-280
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• 1986

The purpose of this study is to obtain the experimental data of the forced flow dryout heat flux in a heat generating debris bed which simulates the degraded nuclear reactor core after severe accident. An experimental investigation has been conducted of dryout heat flux in an inductively heated bed of steel particles with upward forced flow rising coolant circulation system under atmospheric pressure. The present observations were mainly focused on the effects of coolant mass flux, particle size, bed height, and coolant subcooling on the dryout heat flux The data were obtained when carbon steel particles in the size distribution 1.5, 2.5, 3.0 and 4.0 mm were placed in a 55 mm ID Pyrex glass column and inductively heated by passing radio frequency current through a multiturn work coil encircling the column. Distilled water was supplied with variation of mass flux from 0 to 3.5 kg/$\textrm{cm}^2$ s as a coolant in the tests, while the bed height was selected as 55 mm and 110 mm. Inlet temperature of coolant varied by 2$0^{\circ}C$ and 8$0^{\circ}C$. The principal results of the tests are: (1) Dryout heat flux increases with increase of upward forcing mass flux and particle size; (2) The dryout heat flux at the zero mass flux obviously depends on the Particle size as Previous studies; (3) The forced flow dryout heat flux in the shallow bed is somewhat higher than that in the deep bed,

• Food Science and Preservation
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• v.19 no.6
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• pp.946-950
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• 2012

The antioxidant activity and whitening effect of the distilled water (DW) and ethanol extracts of the Prunus persica flower and calyx were studied. In the oxygen radical absorption capacity (ORAC) assay for antioxidant activity measurement, it was confirmed that the flower extract was stronger than the calyx extract, and that the ethanol extract was relatively stronger than the DW extract. To define the whitening effect, an experiment was conducted involving tyrosinase inhibitory assay and measurement of the melanin content of B16F10. As a result of the use of tyrosinase, the DW extract of calyx showed 53% inhibition as the highest activity. The melanin content inhibitory rates were defined as 57% for the ethanol flower extract and 63% of the ethanol calyx extract, based on a $10{\mu}g/mL$ concentration. Based on these results, mixture with the whitening effect in the extract of P. persica and another compounds should be researched for development as a cosmetic ingredient.

• Food Science and Preservation
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• v.25 no.1
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• pp.19-26
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• 2018

In this study, we aimed to increase the utilization of non-commercializable peach fruits collected during harvesting and distribution and to promote the transition of a high value-added industry. After producing pastes from the flesh of different peach varieties, we used these pastes as ingredients in the production of Kochujang. We then performed a comparative analysis on the quality characteristics of the peach-added Kochujang and commercially available Kochujang products. Peach-added Kochujang exhibited a lower pH and reduced sugar, salinity, reducing sugar, ash, and calorie content than those of commercially available Kochujang products. However, the Kochujang had slightly higher pH and moisture content than commercially available products due to high organic acid and moisture contents of peach flesh. In terms of content of inorganic elements, commercial Kochujang products exhibited higher sodium and magnesium content, whereas peach-added Kochujang had higher potassium content. In particular, the lower sodium and higher potassium content of peach-added Kochujang indicates that this product could be used as a functional food to prevent various diseases caused by excessive sodium intake among Koreans. After comparing the products in terms of phenol and flavonoid content, we concluded that ethanol extracts of peach-added Kochujang showed higher phenol content than those of the commercially available Kochujang products. In contrast, the distilled water extracts of peach Kochujang showed higher DPPH free radical scavenging activity than that of commercially available Kochujang products.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.330-341
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• 2018

This study was performed to investigate and measure the antimicrobial activity of evergreen woody species extracts on Trichophyton mentagrophytes. To do this, leaves and stems were collected from Wando and Jeju islands, and were used for the extraction with different solvents (i.e., distilled water, 80% ethanol, and 100% methanol), and at different ultrasonic extracting times (i.e., 15, 30, and 45 minutes). The experiment was conducted by using the agar diffusion method. The clear zone was measured after incubating the paper disc containing the plant extract in a bacterial culture medium. The controls were synthetic antimicrobials, methylparaben and phenoxyethanol, at concentrations of 0.4, 1, 2, and 4 mg/disc. Altogether, extracts of 56 out of 64 species used in this study had inhibitory activity, which confirmed their antimicrobial activity against Athlete's foot. Among them, the crude ethanolic extract of Elaeocarpus sylvestris in 45 min showed a zone of inhibition < 20.2 mm, while the clear zone of Actinodaphne lancifolia ethanolic extraction for 30 min was 23.5 mm. Also, Quercus acuta, Dendropanax morbiferus and Daphne odora showed clear zones of 28.0 mm (45 minutes ethanolic extraction), 20.5 mm (45 minutes crude methanolic extraction) and 19.7 mm (45 minutes methanolic extraction), respectively. Thus, these results confirm that the extracts of evergreen woody species have therapeutic potential against Athlete's foot, and suggest that in order to extract adequate amounts of antimicrobial substance from the plant sources, ideal extraction condition has to be considered.

• Resources Recycling
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• v.30 no.5
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• pp.38-48
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• 2021

In this study, we determine the optimal process conditions for selectively recovering Si from a solar cell surface by removal of impurities (Al, Zn, Ag, etc.). To selectively recover Si from solar cells, leaching is performed using HCl solution and an ultrasonic cleaner. After leaching, the solar cells are washed using distilled water and dried in an oven. Decompression filtration is performed on the HCl solution, and ICP-OES (Inductively Coupled Plasma Optical Emission spectroscopy) full scan analysis is performed on the filtered solution. Furthermore, XRD (X-ray powder diffraction), XRF (X-ray fluorescence), and ICP-OES are performed on the dried solar cells after crushing, and the purity and recovery rate of Si are obtained. In this experiment, the concentration of acid solution, reaction temperature, reaction time, and ultrasonic intensity are considered as variables. The results show that the optimal process conditions for the selective recovery of Si from the solar cells are as follows: the concentration of acid solution = 3 M HCl, reaction temperature = 60℃, reaction time = 120 min, and ultrasonic intensity = 150 W. Further, the Si purity and recovery rate are 99.85 and 99.24%, respectively.