• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.818-826
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• 2013

To reduce the production cost of Lactobacillus, discarded red ginseng starch was collected from a factory of red ginseng extract in order to develop the Lactobacillus culture medium. According to the analysis of the gensenoside composition of red ginseng starch, the total gensenoside content of starch was 2.73 mg/g, and the gensenoside $Rb_1$, $Rb_2$ and $Rg_3$ contents were 0.1, 0.29 and 0.52 mg/g, respectively. For the preparation of the liquid media, red ginseng starch was added at rates of 0, 5, 10 and 20%. Further, Lactobacillus plantarum 15357 and Leuconostoc mesenteroides sub sp. strains were then inoculated to these prepared broths. With the red ginseng starch medium, the growth rates ($1.42{\times}10^7$ and $2.96{\times}10^{10}$ CFU/mL) and the final cell concentrations were higher than the MM medium ($1.0{\times}10^7$ CFU/mL). The optimal concentration of red ginseng starch and yeast extract as a medium were 20% and 10 g/L, respectively. Under these conditions, the cell mass of L. plantarum 15357 and L. mesenteroides sub sp. reached $5.11{\times}10^{10}$ and $8.17{\times}10^{10}$ CFU/mL. These results show a great possibility for the utilization of red ginseng starch as economic medium sources in the production of cell mass of lactic acid bacteria. This is the first trial of development of economic LAB growth medium using discarded red ginseng starch.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.90-96
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• 2002

The STS contents, emphasized in the 6th curriculum, in the chemistry textbooks(II) were analyzed. The STS contents in textbooks showed average value of 2.7%. The chapter of ‘chemical bond and compound' were included 3.8% of STS contents. And the chapter of ‘atomic structure and periodic table', ‘state of material and solution', ‘science of material', and ‘chemical reaction' contained 3.2%, 2.2%, 1.9%, and 1.9% of STS contents, respectively. When the STS contents were analyzed by STS topics of Piel, the results are as follows; 33.7% on effect of technological developments, 27.5% on environmental quality and utilization of natural source, 19.6% on human engineering, 13.8% on energy, and 5.4% on sociality of science. However, there were no topics on population, space research and national defense. When the STS contents were analyzed by student activities of SATIS, most of the activities were research and case study. There were few field activities of practical investigation, problem solving and decision making, research design and stimulation. There were no activities of role play.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.235-244
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• 2009

This experiment was conducted to develop a new silage inoculant for barley at forage analysis laboratory, Grassland and Forages Division, National Institute of Animal Science, RDA from 2000 to 2002. Barley is very important crop in Korea. The great part of them is utilized as forage. Generally, it contains a lot of grains that are feed of animal, especially whole crop silage in ruminant. Efficient lactic acid bacteria were isolated from good barley silage by plating MRS agar containing 0.02% sodium azide, and assessed by growing and acid producing ability in MRS broth. Four lactic acid bacteria were selected, and were found to be Gram positive, rods and catalase negative and were identified to be Lactobacillus plantarum on the basis of the biochemical characteristics and utilization of substrates. Barley was ensiled at dough stage following treatment with four lactic acid bacteria, commercial inoculant, and no additive (control). After 2 months, B2-2 bacteria inoculated silage was lower pH and higher lactic acid content than others treatments. The Flieg's score and grade of B2-2 bacteria treated silage were higher than commercial inoculant. According to this experiment, Lactobacillus plantarum B2-2 (NLRI 201) was recommendable for good silage inoculant of whole crop barley silage.

• The Journal of the Korea Contents Association
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• v.14 no.1
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• pp.30-39
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• 2014

The purpose of this study is to suggest the feasible strategies to vitalize e-learning through investigating the characteristics of e-learning and the evaluations of distance learners on online courses in the domestic universities in Korea. First, in order to accomplish this, 10 Universities and 17 Cyber Universities were selected to explore their characteristics and main projects of e-learning for the administration level investigation. Secondly, content analysis of the bulletin board systems(BBS) and in-depth interviews on distance learners in Cyber Universities were conducted for the user level investigation. The results revealed that Universities in Korea were focused on establishing mobile or smart campuses, diversifying online educational contents, enhancing online interactive systems, and educating e-learning system and smart device utilization. However, distance learners reported that mobile e-learning lacked stability when taking online courses despite its convenience for purpose of academic administration. In addition, distance learners requested the social application workshops to improve on their learning experience as well as the interactions among peers. Therefore, it is important to focus more on how to establish the education-oriented e-learning environment rather than how to implement the administrative projects to animate e-learning in the domestic universities in Korea.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.594-603
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• 2013

In this study, we analyzed the needs of open university students for e-textbooks by conducting focus group interviews (FGIs) and surveys in order to develop an e-textbook that is suited to their needs. The FGIs revealed that readability and portability of e-textbooks were the most important features for students. The surveys showed that of the 276 respondents who participated in the study, only a small number owned smartpads; however, a sizeable number of students intended on purchasing the device in the future. In addition, students' smartpad utilization, time spent reading e-books, and time allotted for studying as opposed to leisure and commercial use of social network services on the smartpad were examined. Students attached importance to the portability, weight, and price of the e-textbook; moreover, they considered the device's ability to support interaction in a variety of ways and rich multimedia resources to be an advantage. Finally, students also felt that e-textbooks should be less expensive than print textbooks; however, they were willing to pay a higher price, depending on the quality of the content.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.312-320
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• 1996

This study was to investigate the changes of phytotoxicity of food waste during composting at an aerated static pile for 80 days. The concentration of sodium in the final compost increased by more than 30% and almost of the sodium was a water soluble type which corresponds to about 94% of the total concentration. Major volatile fatty acid(VFA) produced during the composting was acetic acid and also somewhat of butyric acid. High concentration of acetic acid during the composting was kept up for a month and then decreased progressively. It suggests that the phytotoxicity by the VFAs produced during composting of food waste could be removed through a stabilization process in a period of about 40 days. From the statistical analysis between germination index(G.I.) and VFAs. or G.I. and sodium, the phytotoxicity of food waste samples was more dependent in the changes of acetic acid concentration than that of sodium concentration. Considering low G.I. value in the final food waste compost which is matured completely, however. the agricultural utilization of the food waste compost may be to have a big problem due to excess sodium of the compost which is impossible to remove by composting and seriously inhibits growth of plants.

• KSBB Journal
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• v.24 no.1
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• pp.41-46
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• 2009

Vegetable oils are desirable inexpensive feedstocks for various bioproducts. The content of unsaturated fatty acids such as oleic and linoleic acids are 22% and 55% for soybean oil, 26% and 60% for corn oil, and 61% and 21% for canola oil, respectively. Keto and hydroxy fatty acids are useful industrial chemicals, used in plasticizer, surfactant, lubricant and detergent formulations because of their special chemical properties such as higher viscosity and reactivity compared with other fatty acids. In this study, a microbial isolate, Flavobacterium sp. strain DS5 (NRRL B-14859), was used to convert oleic acid to 10-ketostearic acid (10-KSA) via 10-hydroxystearic acid (10-HSA). Two bioconversion products, 10-KSA and 10-HSA, were quantitatively and qualitatively analyzed using gas chromatography, gas chromatography-mass spectrometry, and $^1H-$ and $^{13}C$-nuclear magnetic resonance. The maximum production of 10-KSA and 10-HSA in flask cultures were 3.4 g/L and 0.5 g/L, respectively. The optimum concentrations of glucose and yeast extract, addition time and volume of oleic acid for 10-KSA production were less than 20 g/L, more than 5 g/L, 18 hand 0.3 ml/50 ml, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.205-212
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• 2010

The effects of chromium (Cr), dietary crude protein (CP) level, and potential interactions of these two factors were investigated in term of energy metabolism in lambs. Forty-eight 9-week-old weaned lambs (Dorper${\times}$Small-tail Han sheep, male, mean initial body weight = 22.96 kg${\pm}$2.60 kg) were used in a 2${\times}$3 factorial arrangement of supplemental Cr (0 ${\mu}g$/kg, 400 $\mu{g}$/kg or 800 ${\mu}g$/kg from chromium yeast) and protein levels (low protein: 157 g/d to 171 g/d for each animal, or high protein: 189 g/d to 209 g/d for each animal). Blood samples were collected at the beginning and end of the feeding trial. The lambs were then sacrificed and tissue samples were frozen for further analysis. Chromium at 400 ${\mu}g$/kg decreased fasting insulin level and the ratio of plasma insulin to glucagon, but these differences were not statistically significant; in contrast, chromium at 800 ${\mu}g$/kg increased the ratio significantly (p<0.05). Protein at the high level increased plasma tumor necrosis factor $\alpha$ (TNF-$\alpha$) level (p = 0.060). Liver glycogen content was increased significantly by Cr (p<0.05), which also increased liver glucose-6-phosphatase (G-6-Pase) and adipose hormone-sensitive lipase (HSL) activity. At 400 ${\mu}g$/kg, Cr increased muscle hexokinase (HK) activity. High protein significantly increased G-6-Pase activities in both the liver (p<0.05) and the kidney (p<0.05), but significantly decreased fatty acid synthase (FAS) activity in subcutaneous adipose tissue (p<0.05). For HSL activity in adipose tissue, a Cr${\times}$CP interaction (p<0.05) was observed. Overall, Cr improved energy metabolism, primarily by promoting the glycolytic rate and lipolytic processes, and these regulations were implemented mainly through the modulation by Cr of the insulin signal transduction system. High protein improved gluconeogenesis in both liver and kidney. The interaction of Cr${\times}$CP indicated that 400 $\mu{g}$/kg Cr could reduce energy consumption in situations where energy was being conserved, but could improve energy utilization when metabolic rate was increased.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.807-817
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• 2008

Steers with ad libitum access to rice straw were assigned to four diets to evaluate the effects of maize or soybean hull supplementation on intake, in vivo digestibility, ruminal pH, VFA, ammonia-nitrogen ($NH_3-N$) and in situ ruminal disappearance of feed nutrients by cattle consuming rice straw. Supplement treatments were: no supplement (RS); soybean meal at 0.127% BW (SBM); cracked maize at 0.415% BW plus 0.044% BW soybean meal (MAIZE); or soybean hulls at 0.415% BW plus 0.044% BW soybean meal (HULLS). The MAIZE and HULLS diets were formulated to provide approximately 4 MJ of $NE_m$ per kg of diet. Rice straw DMI was not affected (p = 0.34) by supplement. Apparent dry matter (DM) digestibility was greater (p<0.001) for MAIZE and HULLS (56.6 and 60.0%, respectively) than for steers consuming SBM or RS (51.8 and 44.4%, respectively). Apparent NDF digestibility was greater (p<0.0004) for HULLS than MAIZE (61.7 vs. 58.0%, respectively) and apparent ADF digestibility was greater (p<0.0008) for HULLS than MAIZE (61.1 vs. 49.2%, respectively). There was no difference in apparent hemicellulose digestibility (p = 0.43). Analysis of ruminal fluid collected 0, 2, 4, 6, and 8 h post-feeding revealed ammonia-nitrogen was greatest (p<0.05) for steers on SBM and HULLS diets at 2 h (24.08 and 22.57 mg/dl, respectively) and total volatile fatty acids was greatest (p<0.05) for HULLS at 4 h (230 mM/L). In situ disappearance, measured at 0, 2, 4, 6, 8, 16 and 24 h, indicated that SBM, MAIZE and HULLS tended to enhance the digestibility of DM and fiber components of rice straw. In situ disappearance of rice straw DM was greatest for SBM and/or HULLS from 4 to 24 h (p = 0.03). Rice straw NDF and ADF disappearance was enhanced by supplementation from 16 to 24 h (p<0.02). Rice straw DM, NDF and ADF disappearances at 24 h were similar for MAIZE and HULLS treatments. When feeding cattle rice straw diets, energy and protein-based supplements are essential. This study showed that fiber-based supplements are just as, if not more, effective as starch-based supplements in rice straw utilization. This study shows that soybean hulls, in spite of their high fiber content, are as efficient as maize for supplementing rice straw primarily because fiber in soybean hulls is highly digestible as shown by in vivo digestibility and in situ disappearance.

• Korean Journal of Microbiology
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• v.44 no.1
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• pp.56-62
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• 2008

Two hundred and sixty-eight bacterial strains were isolated from pine mushroom (Tricholoma matsutake) basal soil. In the course of screening for antifungal activity against seven plant pathogenic fungi (Alternaria panax, Botrytis cinerea, Colletotrichum gloeosprioides, Fusarium oxysporum, Phytopthora capsici, Pythium ultimum, Rizoctonia solani) of isolates, strain KM1-15 showed strong antibiotic activity against Alternaria panax and Colletotrichum gloeosprioides. In determining its relationship on the basis of 16S rDNA sequence, KM1-15 strain was most closely related to Bacillus $koguryoae^T$ (AY904033) (99.62%). When assayed with the API 50CHE Kit, unlike Bacillus koguryoae, it is positive for utilization of L-arabinose, cellobiose, inulin, and D-turanose. Results of cellular fatty acid analysis showed that major cellular fatty acids were 15:0 anteiso (35.78%) and 17:0 anteiso (17.97%). In particular, hydroxyl fatty acids such as 13:0 iso 3-OH, 14:0 iso 3-OH, 15:0 iso 3-OH, and 17:0 iso 3-OH were only restricted to strain KM1-15. DNA G+C content was 43.7 mol% and quinone system was MK-7 (100%) in strain KM1-15.