• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.238-245
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• 1998

The reasonable level of nitrogen fertilizer is a key factor to reduce environmental contamination as well as to increase crop yield and quality. The treatments are $N=42kg\;10a^{-1}$, $N=48kg\;10a^{-1}$, $N=54kg\;10a^{-1}$. $N=60kg\;10a^{-1}$. $N=72kg\;10a^{-1}$ and $N=150kg\;10a^{-1}$. Analytical results of yield and quality of tea leaves harvested the second time are summarized as follows: The soil of experimental field was higher in organic matter($49.9g\;kg^{-1}$) and available phosphate($937mg\;kg^{-1}$) compared to the general field but lower in pH(5.07) compared to the general field. When the amount of nitrogen fertilizer application was raised, the yield of tea leaves, the content of nitrogen, total free amino acids, caffeine and chlorophyll increased: however, the yield of tea leaves increased to excessive levels. On the other hand, the increased level of nitrogen fertilizer did not show any difference in the contents of vitamin C and tannin. Eleven kinds of amino acids were isolated from second harvested leaves of tea where the content of theanine occupied over 50%, and content of $665{\sim}763mg\;100g^{-1}$. The contents of fatty acids and catechin did not show correlation with application level of nitrogen fertilizer. The content of fatty acid was produced $1,742{\sim}2,643mg\;100g^{-1}$, and content of catechin was produced 12.47~13.54%. In scoring test, $N=60kg\;10a^{-1}$ treatment was 0.5~6.0 point higher compared to other treatments. Consequently, $N=60kg\;10a^{-1}$ is considered to be the best level of nitrogen fertilizer in terms of decreased environmental contamination as well as to increase crop yield and quality.

• Korean Journal of Medicinal Crop Science
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• v.8 no.3
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• pp.225-233
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• 2000

There was not noticeable differences in decreasing blood alcohol concentrations between Korea and China-produced Hovenia dulcis $T_{HUNB}$, showing only 1-2 % higher decreasing rate for Korea-produced seed extracts than those from China. It was also found that the blood alcohol decreasing ability was greatly enhanced by partitioning the crude extracts produced from both places. The both extracts (crude and partitioned) accelerated the reducing rate of blood alcohol concentrations down to 1-2 hours, compared to that of control (taking only ethanol). The crude extracts from imported seeds seemed to have slightly better effect on improving in vivo ADH and ALDH activities than domestic ones; however, not for partitioned extracts. It was interesting that the partitioned extracts from both countries enhanced ADH enzyme activity up to 60% than the crude, compared to the control, while ALDH activity was not much affected by the partitioned extracts. It was also confirmed that both ADH and ALDH activities were well balanced in controlling blood alcohol concentration maintaining 28-29% of enzyme activities in vivo. The extracts proved to have better effect on enhancing ALDH activity than ADH activity, which is one of possible explanation that Hovenia dulcis $T_{HUNB}$ can effectively relieve the hangover by fast decreasing acetaldehyde concentration in the liver and blood. GST activity was also increased in the range of 120 to 300% by adding crude or partitioned extracts from both countries; however, there was no difference in enhancing GST activity between the extracts from two countries. The extracts showed competitive inhibition with GST activity, showing the reduction of enzyme activity at higher than 0. 6 (g/L) of the imported extracts.

• Journal of dental hygiene science
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• v.16 no.4
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• pp.272-283
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• 2016

This study compared and analyzed the occluding effects of fluoride compounds and desensitizers, which are commonly used in dental clinics, on dentinal tubules. This study also evaluated the persistence of the active ingredients over time by performing toothbrushing with an electric toothbrush. Thirty-five molar teeth, which had been extracted within the past 3 months from healthy people without tooth decays, amalgam fillings, or dental crowns, were divided into 4 pieces each. Of these, 135 teeth pieces were used as study specimens. These specimens were divided into a control group, an untreated group, and 5 experimental groups (acidulated fluoride gel, fluoride varnish, Gluma, Super Seal, and SE-Bond). The specimens were then subjected to toothbrushing equivalent to 1 week (140 times), 2 weeks (280 times), and 4 weeks (560 times), and the occluding effects on dentinal tubules in 3 regions of each specimen were examined under a scanning electron microscope. The fluoride varnish treated group showed the highest degree of dentinal tubule occlusion effects during the first, second, and fourth weeks of toothbrushing, with the SE-Bond treated group showing the second highest degree and the Gluma treated group showing the lowest degree. After 4 weeks of toothbrushing, the Gluma treated group and the Super Seal treated group showed the lowest degrees of dentinal tubule occlusion effects. In summary, the fluoride varnish treated group and the SE-Bond treated group displayed higher occlusion effects even after 4 weeks of treatment than did the other experimental groups. Therefore, it is the authors' belief that fluoride varnish and SE-Bond are effective for treating dentinal hyperesthesia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1402-1408
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• 2012

Mulberry pomace, a by-product obtained from mulberry juice, has not been utilized as food. In this study, antioxidant activities, proximate composition and physiochemical characteristics of mulberry pomace were evaluated and compared with those of mulberry fruit or mulberry concentrate. Mulberry fruit was pressed and filtered. The filtrate and residue were used as mulberry juice and mulberry pomace, respectively. Mulberry juice was evaporated, after which a concentrate ($24.7^{\circ}Brix$) was obtained. Moisture contents of mulberry concentrate, freeze-dried mulberry, and pomace were 68.7%, 6.03%, and 7.32%, respectively. Reducing sugar contents were 45.7% in freeze-dried mulberry, 24.5% in pomace, and 30.9% in mulberry concentrate. The pH and acidity of the three samples ranged from 5.80~5.92 and, 0.035~0.080%, respectively. Carbohydrate and crude ash contents were the highest in mulberry fruit, whereas crude protein, fat, and fiber contents were the highest in pomace. Redness of the Hunter color system was 4.7 in mulberry and 4.3 in pomace. Total phenolic content was the highest in mulberry fruit, whereas total flavonoid content was the highest in pomace. Antioxidant activities (DPPH, hydroxyl, and ABTS radical scavenging activities) were enhanced in the order of mulberry fruit> pomace> mulberry concentrate. Especially, antioxidant activities, such as DPPH and hydroxyl radical scavenging activities, of mulberry pomace were similar with those of mulberry fruit. Based on these results, freeze-dried mulberry pomace may be considered as a functional as well as an additive material for food processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1145-1152
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• 2009

For the utilization of Korean ginseng (Panax ginseng C.A. Meyer) in the functional drink, we prepared the fermented Korean ginseng with mushroom mycelia (Ganoderma lucidum; WG-GL, Hericium erinaceum; WG-HE and Phellinus linteus; WG-PL) by solid culture. A proximate analysis showed that the fermented Korean ginseng contained significantly more crude fat (4.66$\sim$12.02%) than Korean ginseng (WG, 1.61%) whereas crude protein content of WG (13.64%) was higher value than those of the ferments (7.60$\sim$12.57%). When we also evaluated effects of the fermented Korean ginseng on the mitogenic activity, hot-water extract from WG-PL was significantly higher than those of WG or mycelia only fermentation (GL, HE and PL) as analyzed by IL-2 production (1.64-fold of the saline control) and proliferation of splenocytes (1.47-fold). In addition, the lysosomal phosphatase activity (WG-HE; 1.32-fold) and NO/TNF-$\alpha$ production (WG-HE; 2.27-fold of the saline control at 50 ${\mu}g$/mL, WG-PL; 3.56-fold, respectively) from macrophage in the presence of the fermented Korean ginseng were higher than those of WG or mycelia fermentation. These results indicate that hot-water extracts from the fermented Korean ginseng with mushroom mycelia by solid culture contain chemical ingredients different from the Korean ginseng, and that it might provide beneficial immunostimulating activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1555-1564
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• 2014

This study investigated the effects of combined treatment of immersion liquids (adjusted pH 4.5 with Citrus junos concentrate (CL), pH 5.5 with Prunus mume concentrate (PL), or no pH adjustment, pH 6.5, control) and high hydrostatic pressure (HHP, 450 MPa) on shelf-life and quality of mackerel. In this study, we measured changes in viable cell counts, pH level, volatile basic nitrogen, thiobarbituric acid reactive substances, color analysis, volatile organic compounds, and sensory evaluation of mackerel at $4^{\circ}C$ for 20 days. CL/HHP and PL/HHP treatments reduced viable cell counts by 3 log cycles during storage compared to the control. Mackerel treated with CL/HHP and PL/HHP showed significantly lower TBARS and VBN levels as compared to the control. After combined treatment, lightness and whiteness increased but redness decreased. VOCs tests showed that contents of alcohol, acid, and ketones in mackerel fillet treated with CL/HHP and PL/HHP were relatively reduced. Especially, CL/HHP and PL/HHP suppressed production of sulfur. In the sensory evaluation, aroma, taste, salinity, hardness, and springiness of mackerel treated with combined HHP showed higher scores than the control. These results suggest that immersion liquids and HHP treatments may increase shelf-life of mackerel and maintain quality during storage at $4^{\circ}C$.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.811-817
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• 2008

The principal objective of this study was to evaluate the effects of baking method on the quality and shelf-life of Maejakgwa containing nuts and seeds. Four different types of nuts and seeds (almond, cashewnut, coconut, and sunflower seed) were added to flour, and baking method was applied to prepare the Maejakgwa, physicochemical properties of which were then evaluated. The proximate composition analysis demonstrated that crude protein, crude fat, and ash contents were higher in the Maejakgwa containing nuts and seeds than in the control group. The lightness (L) value of the control Maejakgwa was lower than that observed in the groups containing nuts and seeds. Maejakgwa made with cashewnut, coconut, and sunflower seed evidenced higher yellowness (b) values than were recorded in the control and coconut groups. The incorporation of cashewnut, coconut and sunflower seed into the Maejakgwa lowered the hardness values (p<0.05). Our consumer test demonstrated that Maejakgwa prepared with almond was the most highly preferred, and the control group was the least favored. After 30 days of storage at $60^{\circ}C$, the peroxide value of the Maejakgwa containing sunflower seed was substantially higher than in any other groups, thereby suggesting that the addition of sunflower seeds resulted in accelerated lipid oxidation. No noticeable changes in peroxide values were observed in the groups prepared with coconut and cashewnut during storage time. The acid value increased with increasing storage time, and the addition of sunflower seed evidenced the highest values as compared to other groups.

• 한국지구물리탐사학회:학술대회논문집
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• 2004.08a
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• pp.104-117
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• 2004

Dmitri Donskoi, which went down during the Russo-Japanese War occurred 100 years ago, was found by using geophysical exploration techniques at the 400 m water depth of submarine valley off Jeodong of Ulleung Island. In the submarine area with the rugged seabed topography and volcanic seamounts, in particular, the reliable seabed images were acquired by using the mid-to-shallow Multibeam exploration technique The strength of corrosion (causticity) of the sunken Donskoi, measured by the electrochemical method, decreased to 2/5 compared with the original strength.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.714-720
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• 2013

We investigated the brewing and fermenting characteristics of makgeolli produced from high-yielding rice varieties. We used the high-yielding indica rice varieties, Anda and Dasan 1, and the japonica varieties, Deuraechan and Boramchan. Our results showed that the rice protein level was the highest in makgeolli produced from Anda ($7.5{\pm}0.2%$), while the amylose level was the lowest in makgeolli produced from the mid- to late-maturing japonica varieties (Deuraechan, $18.9{\pm}0.7%$; Boramchan, $18.9{\pm}1.4%$). Samples of makgeolli produced from Anda, Deuraechan, and Boramchan by using the Ipguk (Koji) method had an alcohol content of 16.6-17.4% on completion of fermentation. By contrast, makgeolli produced from Dasan 1 had an alcohol content of 14.3%; further, the makgeolli differed significantly in the sensory test and was scored as excellent regarding comprehensive preference. For makgeolli produced by using the uncooked rice fermentation method, samples produced from the indica varieties, Anda and Dasan 1, had lower alcohol contents (17.2% and 17.0%, respectively) and higher total acidity levels (0.33% and 0.31%, respectively) than did samples produced from the japonica varieties, Deuraechan and Boramchan (0.28% for both). In the sensory test, samples produced from Anda and Dasan 1 performed significantly better regarding scent, swallowing, and comprehensive preference.

• Korean Journal of Poultry Science
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• v.45 no.2
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• pp.125-135
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• 2018

This study was conducted to evaluate the productivity and meat quality of three newly-developed crossbreds of Korean native chicken (2A, 2C, and 2D) as compared with commercial Korean native chicken (CKNC) and commercial broiler. Totally, 400 birds of different crossbreds were randomly allotted to eight pens, each with 50 birds. The birds were reared ad libitum and slaughtered at the age of 12 weeks. Fifty male chickens were slaughtered at the same day in the same slaughterhouse were selected for the comparison of meat quality. The crossbred 2C had greater body weight than that of CKNC (P<0.05), and had similar uniformity with lower death rate. Although shank length of 2C was the longest among the Korean native chicken breeds, the ratio of shank length to body weight was the lowest among them (P<0.05). The crossbred 2C had similar inosine 5'-monophosphate (IMP) content as that of CKNC in breast meat, and the highest IMP content in thigh meat (P<0.05). In a sensory analysis, the crossbred 2C generally showed, similar savory taste and texture as that of CKNC, and the overall acceptability of thigh meat was the highest in CKNC and broiler. Based on the present results, the possibility of commercialization of a newly-developed crossbred of Korean native chicken was confirmed.