• Korean Journal of Plant Resources
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• v.28 no.4
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• pp.391-399
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• 2015

There has been little research on the harvesting time-dependent changes in the antioxidant activities of new varieties of highland cultures of Gomchwi (Ligularia fischeri) crossed with Turcs (Ligularia fischeri (Ledeb.)) and Nakai (Ligularia fischeri var. spiciformis), namely Sammany (S), Gommany (G) and Damogy (D). This study was conducted to assess the effect of different harvesting times on nutritional and health-related properties such as total phenolic contents, flavonoids, DPPH (1,1-diphenyl-2-picrylhydrasyl) free radical scavenging activities and reducing power. From these harvests, extracts were prepared using methanol. Total phenolic content in Jul 14-G (Gommany harvested on July 14, 0.172 ㎎·GAE/ml) was higher than that in other products harvested after the same period (S, 0.154; D, 0.141 ㎎·GAE/ml). Flavonoid content was higher in Jul 3-G (0.114 ㎎·QE/ml), compared to Jul 3-S (0.113 ㎎·QE/ml) and Jul 14-D (0.089 ㎎·QE/ml). Antioxidant activities were higher in samples harvested after June 12 in all cases. On July 14, the highest DPPH free radical scavenging activities among all harvest dates were seen (92.875~94.595%). The reducing power was also dependent on harvest day (Abs 0.5~0.6 on July 14), showing a pattern similar to that of DPPH free radical-scavenging activities. Antioxidant activity and harvesting times seem to correlate with total polyphenol and flavonoid contents.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.154-163
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• 2005

Chemical and flavor components of Bulro Kugi (Lycium chinense Mill) fruit leaf, and root were compared. Fructose and glucose were detected in fruit and leaf, and sucrose in root, respectively. Citrate was the highest among organic acids in fruits, and malate in leaf and root Capsaicin was detected in leaf and root. Volatile flavor compounds were extracted by simultaneous distillation and extraction method using Likens and Nickerson's extraction apparatus. Concentrated flavor extract was analysed, and 128 compounds, including 22 acids 15 alcohols, 12 aldehydes, 8 esters, 10 furans, 26 hydrocarbons, 4 phenols, 2 pyrroles, 1 pyrazine, and 28 miscellaneous components. were identified by GC and GC-MS. Main volatile compounds were hexadecanoic acid and 2-furancarboxaldehyde in hot-air dried fruit, hexadecanoic acid and 1-hexadecene in fresh fruit, 3, 7, 11, 15-tetranethyl-2-hexadecan-1-ol and hexadecanoir acid in leaf, and hexadecanoic acid in root.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.154-159
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• 1992

An investigation was carried out to study the feasibility of tofu preparation with using isolated soyprotein(ISP) only. The ISP tofu was prepared by boiling the ISP suspension for 2 min before addition of coagulants. Effects of coagulants($CaSO_{4},\;CaCl_{2}\;MgCl_{2}\;GDL$) and coagulation temperature in the range of $2{\sim}95^{\circ}C$ were studied on the amounts of coagulants required, size and shape of coagulates, volume yield and textural properties of tofu. It was found that amounts of coagulants and tofu volume was significantly reduced and the larger and cloud-like shape was obtained as the coagulation temperature increased. A rather precipitation was occured under $40\;or\;50^{\circ}C$, which caused difficulty for tofu formation by pressing. GDL and $CaSO_{4}$ showed higher yields than those of $CaCl_{2}\;and\;MgCl_{2}$ at low temperature range and little difference at high temperature. In the textural properties of hardness, brittleness and gumminess of tofu were almost lineary and rapidly increased as the coagulation temperature increased where $CaCl_{2}\;and\;GDL$ produced highest and lowest of those values, respectively. The elasticity was reduced as the temperature increased for those made with $MaCl_{2},\;CaSO_{4}\;GDL\;and\;CaCl_{2}$, tofu showed little change.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.154-160
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• 2000

Protease production and its characteristics were investigated with Bacillus subtilis PCA20-3 which was isolated from Korean traditional meju. The optimum culture conditions of Bacillus subtilis PCA20-3 for the production of the protease were as follow: 0.2% soytone, 2% starch, 0.1% $(NH_4)_2SO_4,\;0.2%\;CaCl_2,\;0.01%\;yeast\;extract,\;0.1%\; K_2HPO_4,\;0.1%\;KH_2PO_4,\;pH\;7.0,\;30^{\circ}C$ and 20 hrs. The optimum pH and temperature for enzyme activity of protease producing Bacillus subtilis PCA20-3 were pH 8.0-10.0 and $55^{\circ}C$, respectively. The enzyme was relatively stable at pH $6.0{\sim}11.0$ and at temperature below $50^{\circ}C$. The activity of the enzyme was inhibited by $Fe^(2＋)\;and\;Cu^(2＋)$. 2 mM phenymethanesulfonyl fluoride inhibited 89.2% of enzyme activity. This indicates that the enzyme is serine protease. The $K_m$ value was $5\;{\times}\;10^{-4}\;M,\;V_{max}\;value\;was\;100\;{\mu}g/min$. This enzyme hydrolyzed casein more rapidly than bovine serum albumin.

• Communications of Mathematical Education
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• v.26 no.1
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• pp.137-154
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• 2012

Approximation' is one of central conceptions in calculus. A basic conception for explaining 'approximation' is 'tangent', and 'tangent' is a 'line' with special condition. In this study, we will study pedagogically these mathematical knowledge on the ground of a viewpoint on the teaching of secondary geometry, and in connection with these we will suggest the teaching program and the chief end for the probable teaching. For this, we will examine point, line, circle, straight line, tangent line, approximation, and drive meaningfully mathematical knowledge for algebraic operation through the process translating from the above into analytic geometry. And we will construct the stream line of mathematical knowledge for approximation from a view of modern mathematics. This study help mathematics teachers to promote the pedagogical content knowledge, and to provide the basis for development of teaching model guiding the mathematical knowledge. Moreover, this study help students to recognize that mathematics is a systematic discipline and school mathematics are activities constructed under a fixed purpose.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.154-161
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• 1997

The germination inhibitory effects of American ginseng (Panax quinquefolium Linne) pulp were discussed. The germination inhibitory effects of pulp juice were decreased in a concentration dependent manner. When the pulp juice was diluted 0 (original juice), 1, 2, 5, 10, 20, 50 and 100 times, the radicle lengths of the assay plant, Chinese cabbage (Brassica chinensis Linne), showed 0, 0.32, 0.72, 3.13, 4.83, 16.07, 16.73 and 23.50 mm, respectively (CK=25.98 mm). The pulp evidently inhibited the embryo growth in natural fruit. The longer was the duration that the pulp stayed around the seed, the longer was the time course needed for embryo getting free from the inhibitory effects of pulp. When the depulping was performed on the day 0, 15, 30 and 60 after harvest, the time courses needed for embryo extricating the residual inhibitory effects from pulp were 30, 75, 135 and 135 days, respectively. Moreover, if the pulp stayed around the seed with time, that would make the seed rotten ratio increase. When the pulp stayed around the seed for 0, 15, 30, 60 and 270 days, the seed rotten ratios were 5.47, 5.71, 19.05, 27.14 and 33.33%, respectively. Therefore, we concluded that the pulp could be included in the inhibitory components which made American ginseng seed get into dormancy.

• Korean Journal of Health Education and Promotion
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• v.19 no.2
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• pp.139-154
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• 2002

This study was conducted to examine to causes and symptoms of stress and factors influencing stress management of workers in beauty shops. 811 people who were working in the shops located in Daegu City and Kyungbuk Province were selected as subjects of this study. Data were collected from April 10, 2000 to July 10, 2000. The results of this study can be summarized as follows. According to general characteristics of the respondents, female was 90.8%. 42.1 % of them was in their twenties and 73.7% of them did not marry. 57.5% of the respondents grew up in big cities and 41.1% had no religion. 63.6% was graduated from junior colleges. 44.6% of them worked for below I year and 33.9% earned below four hundred and ninety thousand won per month. 55.8% of them was satisfied with their work aptitude, while 34.2% was not satisfied with it. In the case of satisfaction level with working environment, ‘common level’ was 46.3%, while 12.8% of them was unsatisfied with it. In the case of stress level by factors of stress related to working, male was higher (9.34 $\pm$ 2.38 points). Those who grew up in towns or villages and those who belonged to the middle class showed high stress level. Those who married and those who graduated from high school also displayed high stress level. It also appeared that monthly income influenced the stress level related to working.. The extent of stress level influencing physical causes appeared in order of health condition, education level, sex, satisfaction level with work aptitude, economic status, and working hours. The extent of stress level influencing whole organizational level appeared in order of satisfaction level with work aptitude, working hours, education level, health condition, and sex. The extent of stress factors influencing depressed feeling of stress symptom appeared in order of working hours, sex, amount of smoking, absence due to stress, age, health condition, and education level. The extent of influencing factors on active stress management appeared in order of satisfaction level with work aptitude, health condition, size of the shop, drinking, sex, and the number of day off. The extent of influencing factors on avoidable stress management appeared in order of age, absence due to stress, drinking, health condition, and sex.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.154-162
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• 1992

This study was designed to investigate the antitumor effect and immunological activities of chitosan extracted from Solenocera prominetis toward on mire bearing sarcoma-180. The growth inhibition ratio of the chitosan toward sarcoma-180 showed at the highest level of 63.84% when chitosan were administrated at the concentration of 40mg/kg. The direct cytotoxic effect of chitosan was not observed in the mice bearing sar-roma-180 in vitro. In the effect of immunological activities, dose-dependent responses indicated by the increase of leucocyte, peritoneal exudate cell than that of control group when chitosan administered to the mice in the concentation of 30mg/kg and 40mg/kg. Also dose-dependent responses showed also by the increase of immunoorgans weights such as body weight, liver, spleen or thymus in the same concentration of 30mg/kg and 40mg/kg. Food pad swelling having the relationship with arthus reaction of antibody-mediated hypersensitivity and delayed type hypersensitivity was recovered the almost normal level. In the efforts of macrophge on phagocytes, there were not substantial differences in phagorytic and corrected phagocytic index. In the number of plaque forming cell(PFC), PFC on the 10$^{7}$ spleen cells were increased the levels of 18.88% and 31.83% when chitosan were adminstersd at the concentration of 30mg/kg and 40mg/kg.

• KSBB Journal
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• v.27 no.1
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• pp.67-74
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• 2012

In this study, the optimum conditions of fermentation were determined by isolating the microorganisms with the ability to bioconvert the Citrus peel flavonoid, and the effect of the fermented Citrus peel extract which was bioconverted on the oxidative damage of HIT-T15 cell was investigated. The Aureobasidium pullulans Y-12 was isolated and identified with the strains having bioconversion activity. The fermentation conditions for bioconversion activity were confirmed to be optimal when culturing for three days at $25^{\circ}C$, 150 rpm in a culture medium containing 5% Citrus peel power and 0.8% casitone. As a result of bioconversion, 32.8 mg/g and 21.5 mg/g of naringenin and hesperetin, which were aglycone flavones, were produced respectively. Also in the flavonoid content, it was confirmed that FCP produced 154.8 mg/g while CP produced 33.7 mg/g, thus producing more by approximately 4.6 times. As a result of treating FCP and CP after inducing the oxidative damage for HIT-T15 cell by treating the deoxy-D-ribose with $IC_{50}$ (38 mM) concentration, the surviving rate was recovered to 90% for FCP treatments in the 0.01 mg/mL concentration and for CP treatments in the 0.025 mg/mL concentration. Also in the insulin secretion rate, FCP treatments increased by 206% and CP treatments by 132% when treated in the 0.1 mg/mL concentration. As the bioconverted FCP can inhibit the oxidative damage of HIT-T15 cell in the low concentration, it was considered its usability as the functional material for prevention of the type 2 diabetes.

• Journal of Environmental Health Sciences
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• v.37 no.3
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• pp.182-192
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• 2011

Objectives: This study aims to identify the influential factors on the pulmonary function of targeted general residents in the areas surrounding Gwangyang Steel Mill. Methods: An PFT (Pulmonary Function Test) was conducted from May 2007 to November 2007 on 974 target residents (438 male, 536 female), including an exposed group (674 people) who resided within a radius of 5 km from Gwangyang Steel Mill in Gwangyang-si, Jeollanam-do and a control group (300 people) who resided outside a radius of 15 km. A survey related to personal characteristics, life habits, respiratory diseases and allergic symptoms, medical histories and living environments of the residents was also conducted to identify influential factors on pulmonary function. Results: As %$FEV_1$ and %FVC of the exposed group are 99.17% and 96.98%, respectively, and those of the control group are 105.47% and 101.91%, respectively, with the PFT values of the exposed group being lower than those of the control group (p<0.001), it turns out that the pollution in the industrial complex is likely to trigger a reduction in the pulmonary function of local residents. The odds ratio analysis result for asthma diagnosis history indicates that the odds ratios tend to be higher among surveyed residents who are living near above-average traffic volumes and are using beds, where it is statistically meaningful that especially the odds ratios are higher if the residences are closer to roads (p<0.01, CI=1.12-4.52). The factors that affect the FEV1 are identified as smoking, passive smoking, asthma diagnosis history, nasal congestion symptoms and allergic eye disease ($R^2$=0.154, p<0.001). The factors that affect the FVC are identified as smoking, passive smoking, asthma diagnosis history and allergic coryza ($R^2$=0.158, p<0.001). In addition, the analysis result for the relevance of air pollution levels to pulmonary function ($FEV_1$, FVC) shows that FEV1 and FVC tend to decrease as the concentration of $O_3$ increases. Conclusions: We believe that this study may provide preliminary data for the development of preventive measures for health effects on the residents and environmental health control measures for environmental pollution in the industrial complex area.