• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1390-1393
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• 2003

Measuring in vivo rate of bone collagen synthesis has so far been technically difficult and often subject to quite large errors. In the present study, bone collagen synthesis rate was measured using a precursor-product method, based on the exchange of $^2$$H_2O$ into amino acids. Mass isotopomer abundance in hydroxyproline from bone collagen was analyzed by gas chromatography/mass spectrometry. The $^2$$H_2O$ labeling protocol consisted of an initial intraperitoneal injection of 99.9% $^2$$H_2O$, to achieve approximately 2.5% body water enrichment followed by administration of 4% $^2$$H_2O$ in drinking water for 9 weeks. Body $^2$$H_2O$ enrichments were stable at 2.7 ∼ 3.0% over labeling Period. In growing rats, the fractional synthesis rate ( $k_{s}$) of bone collagen was 0.066 $\pm$ 0.049 w $k^{-1}$ . The unique features of stable $^2$$H_2O$ pools and label incorporation allowed the precursor-product approach to be used for measuring bone collagen synthesis rate..

• Journal of Life Science
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• v.18 no.10
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• pp.1377-1383
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• 2008

A bacterium producing non- or partially digestible dextran was isolated from kimchi broth by enrichment culture technique. The bacterium was identified tentatively as Leuconostoc sp. strain SKY. We established the response surface methodology (Box-Behnken design) to optimize the principle parameters such as culture pH, temperature, and yeast extract concentration for maximizing production of dextran. The ranges of parameters were determined based on prior screening works done at our laboratory and accordingly chosen as 5.5, 6.5, and 7.5 for pH, 25, 30, and $35^{\circ}C$ for temperature, and 1, 5, and 9 g/l yeast extract. Initial concentration of sucrose was 100 g/l. The mineral medium consisted of 3.0 g $KH_2PO_4$, 0.01 g $FeSO_4{\cdot}H_2O$, 0.01 g $MnSO_4{\cdot}4H_2O$, 0.2 g $MgSO_4{\cdot}7H_2O$, 0.01 g NaCl, and 0.05 g $CaCO_3$ per 1 liter deionized water. The optimum values of pH and temperature, and yeast extract concentration were obtained at pH (around 7.0), temperature (27 to $28^{\circ}C$), and yeast extract (6 to 7 g/l). The best dextran yield was 60% (dextran/g sucrose). The best dextran productivity was 0.8 g/h-l.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.164-170
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• 2000

This study was carried out to investigate the effect of photosynthetic bacteria to chlorella or ${\omega}-yeast$ on Browth of the rotifer and its dietary value for flounder, Paralicbthys oliraceus. The rotifer fed the chlorella (200,000 cells/ind./day) with the addition of 20 times the photosynthetic bacteria of the chlorella concentration showed the highest growth. But the specific growth rate of 100,000 chlorella/ind./day with the addition of 30 times the photosynthetic bacteria was the most economical feeding regime for mass culture of the rotifer. The rotifer frd ${\omega}-yeast$ with 200,000 cells/ind./days with the addition of 20 times the photosynthetic bacteria of the chlorella conecentration showed the highest growth. Growth and survial rate of the larvae of Paralichithys oiivaceus fed the rotifer reared on both chlorella and ${\omega}-yeast$ with the addition of photosynthetic bacteria were higher than those without the bacteria, and the chlorella had better dietary value than the ${\omega}-yeast$ for the larvae. The larvae fed the rotifer which was cultured with the chlorella of 200,000 cells/ind./day and the photosynthetic bacteria of $4{\times}10^6$ cells/ind./day showed the highest survial rate and growth. The larvae reared with the addition of the photosynthetic bacteris had higher total lipid and the total content of EPA and DHA than those reared without the bacteria. The larvae fed the enriched artemia nauplius with the photosynthetic bacteria also showed higher suurval rate and growth than those fed the nauplius without the enrichment. The optimum enrichment concentration of the photosynthetic bacteria for artemia nauplius was $2{\times}1^7\;cells/ml$. The addition of the photosynthetic bacteria to the chlorella and the ${\omega}-yeast$ was effective to growth of the rotifer and dietary value for the flounder larvae. However, an excessive addition of the bacteria decreased both the growth of the rotifer and the dietary of the larvae.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.263-270
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• 2015

A bacterial strain producing extracellular mannanases was isolated from soil of chestnut tree farm located in Gongju city of Korea by enrichment culture using Avicel as a carbon source. 16S rDNA sequence of the isolate YB-43 was highly homologous to those of genus Cellulosimicrobium strains with sequence similarities of above 99.6%. Mannanase productivity was significantly increased when the Cellulosimicrobium sp. YB-43 was grown in the presence of locust bean gum (LBG) or konjac. The mannanases were partially purified to be mannanase A (ManA) and mannanase C (ManC) by DEAE-Sepharose column and Q-Sepharose column chromatography from the culture filtrate of Cellulosimicrobium sp. YB-43 grown in LB medium supplemented with 0.7% LBG for 24 h. The partially purified ManA showed the highest activity at $55^{\circ}C$ and pH 6.5, while ManC activity was optimal at $65^{\circ}C$ and pH 7.5. ManA was stable up to $40^{\circ}C$ for 1 h, but ManC activity decreased significantly even after 1 h at $20^{\circ}C$. ManA and ManC showed difference from each other according to their substrate specificities and predominant products resulting from the mannanase hydrolysis for mannooligosaccharides. As a result, Cellulosimicrobium sp. YB-43 was found to produce two different kinds of mannanases.

• Journal of Distribution Science
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• v.14 no.2
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• pp.113-121
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• 2016

Purpose - The purpose of this study is to identify team commitment affecting employees' innovative activities and factors affecting team commitment including empowerment by leaders and job enrichment factors. In other words, so as to explain outcome variables of innovative activities, this study aims to emphasize employees' attachment roles towards their groups within nomological network, and identify the motives encouraging employees' innovative activities. The research purpose is significant due to the realistic situation of hotel industry. The reason why innovative activities are important can be found in recent changes of business environment. Also, unlike other various studies on precedence factors encouraging employees' innovative activities, this study classified those precedence factors into job and leader characteristics, and it emphasized the importance of team commitment as the process that job and leader characteristics are connected to innovative activities. Research design, data and methodology - The survey for this study was conducted during October 6^th ~ November 10^th in 2014 to the employees who are working in 5-star hotels in Korea. As for the selection of hotels and sampling method, convenience sampling method was used to the employees in 5-star hotels. Self-report method was used in the survey, judging that the employees' characteristics would be relatively homogeneous. 311 questionnaires were distributed in total, and 275 reponses were collected. After excluding the missing and unreliable responses, 245 questionnaires were used in the research. SPSS and AMOS programs were used for the analysis. Results - First, empowering leadership had positive effects on hotel employees' team commitment. It indicates that hotel employees are more committed to their team when their leaders set examples, provide information, and involve employees in decision-making process. Second, as a result of the relationship analysis in task diversity, task significance, task identity and team commitment, task diversity and task significance had significant effect on team commitment, while task identity had no significant effect on team commitment. It indicates that team commitment is enhanced when the employees can conduct diverse types of jobs and get more opportunities to talk with the guests. Also, the repetition for the same jobs in hotel rooms and the space for preparing food and beverage do not lead to team commitment, even though the employees fulfill their duties to the end. Third, hotel employees' team commitment has positive effect on their innovative activities. It indicates that employees voluntarily conduct innovative activities when they are attached to their team and identifies themselves with the team. Conclusions - There are theoretical and practical implications in this study. First, in terms of the theoretical perspective, this study proposes structural framework in team commitment, and it identifies the psychological mechanism in team commitment from the aspect of social exchange, which resulted in identification of precedence factors related to team commitment. In addition, this study presents new possibilities for relevant studies about team commitment by examining the effect on team commitment when the importance of innovative activities is emphasized in recent business environment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.4
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• pp.285-292
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• 2010

To prepare high-quality fast foods using salmon, this study developed a docosahexaenoic acid (DHA)-enriched salmon patty, and compared its quality with soybean oil-added patty and commercial patty. The moisture and lipid contents of the DHA-enriched patty were 61.9% and 7.7%, respectively. The moisture content was lower than in the commercial patty, while the lipid content was higher. The lipophilic and hydrophilic browning indices of the DHA-enriched patty were 0.10 and 0.05, respectively, which were lower than those of the commercial patty. The DHA-enriched patty had 5% less trichloroacetic acid (TCA)-soluble nitrogen than the commercial patty, and it was firmer. There were no differences in the proximate composition, browning indices, TCA-soluble nitrogen content, and hardness between the soybean-added and DHA-enriched patties prepared in this experiment. Examining the fatty acid compositions of the patties, the saturated acid and monoenoic acid compositions decreased in the following order: DHA-enriched patty > soybean oil-added patty > commercial patty, while the polyenoic acid composition increased in that order. The total amino acid content of the DHA-enriched patty was 19.13 g/100 g, which was 32% higher than that of the commercial patty (14.47 g/100 g). No enriching effect of minerals would be expected on eating a 100 g DHA-enriched patty, except for phosphorus. The sensory evaluation indicated that the DHA-enriched patty was superior in color and taste to the commercial patty, while there was no difference in flavor between the patties.

• Molecules and Cells
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• v.41 no.11
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• pp.979-992
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• 2018

Potato (Solanum tuberosum L.) is the third most important food crop, and breeding drought-tolerant varieties is vital research goal. However, detailed molecular mechanisms in response to drought stress in potatoes are not well known. In this study, we developed EMS-mutagenized potatoes that showed significant tolerance to drought stress compared to the wild-type (WT) 'Desiree' cultivar. In addition, changes to transcripts as a result of drought stress in WT and drought-tolerant (DR) plants were investigated by de novo assembly using the Illumina platform. One-week-old WT and DR plants were treated with -1.8 Mpa polyethylene glycol-8000, and total RNA was prepared from plants harvested at 0, 6, 12, 24, and 48 h for subsequent RNA sequencing. In total, 61,100 transcripts and 5,118 differentially expressed genes (DEGs) displaying up- or down-regulation were identified in pairwise comparisons of WT and DR plants following drought conditions. Transcriptome profiling showed the number of DEGs with up-regulation and down-regulation at 909, 977, 1181, 1225 and 826 between WT and DR plants at 0, 6, 12, 24, and 48 h, respectively. Results of KEGG enrichment showed that the drought tolerance mechanism of the DR plant can mainly be explained by two aspects, the 'photosynthetic-antenna protein' and 'protein processing of the endoplasmic reticulum'. We also divided eight expression patterns in four pairwise comparisons of DR plants (DR0 vs DR6, DR12, DR24, DR48) under PEG treatment. Our comprehensive transcriptome data will further enhance our understanding of the mechanisms regulating drought tolerance in tetraploid potato cultivars.

• Journal of Dairy Science and Biotechnology
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• v.34 no.2
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• pp.83-89
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• 2016

This study was designed to determine the mutagenic potential of hydrolyzed glycomacropeptide (GMP) powder (hereafter referred to as 23%-GNANA; product name: HELICOBACTROL-23) in a micronucleus test using bone marrow in ICR mice. Three experimental groups were used: a 3-step concentration group, with a maximum concentration of 2,000 mg/kg, and other sequentially two-fold lower concentrations, a negative control group, and a positive control group. The test material was administered for 2 d to observe the frequency of micronucleus formation up to 48 h after the test material was absorbed by the body. When the polychromatic erythrocyte (PCE) content of erythrocytes was compared, no significant differences were noted between the negative control group and the test group (p<0.05). Similarly, when the average numbers of micronucleated PCE (MNPCE) in 2,000 PCE per animal were compared, no significant difference was observed between the negative control group and the test group (p<0.05). No dose-response relationship with regard to the concentration of the test material administered was noted. These results allow us to conclude that hydrolyzed whey protein powder does not cause formation of micronuclei in mouse bone marrow cells under the applied conditions. In this study, the average frequency of micronucleus formation in PCE was significantly higher in the positive control group compared with the negative control group; thus, the test conditions were appropriate for detecting the frequency of micronucleus formation induced by the test material. In conclusion, the safety of 23%-GNANA test substance was verified in an in vivo micronucleus test in mice, conducted before the registration of HELICOBACTROL-23 as a food additive.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.8
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• pp.1310-1322
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• 2020

Objective: The current study was conducted to evaluate the quality and profile of fatty acid in the breast and thigh, and the performance of broilers fed diets containing seed or oil of chia (Salvia hispanica L.) as a replacement for soybean, in the rearing period from 29 to 42 days of age. Methods: On the 29th day of age, 120 broilers were distributed in four treatments evaluated in five replicates of six birds. The grain or oil of soybean was respectively replaced on a weight-to-weight basis in the formulation by the seed or oil of chia, constituting the experimental diets. The roasted whole soybean and chia seed were included in the feed at 16.4%, whereas the soybean and chia oils were included at 2.5%. Results: The dietary chia oil increased the lipid peroxidation in the thigh meat, and the dietary chia seed increased the cooking loss of the thigh. However, for the other physicochemical parameters evaluated and for the proximate composition of the breast and thigh, in general, the inclusion of chia seed or oil in the diet provided similar or better results than those observed when the diets contained soybean oil or roasted whole soybean. With regard to the fatty acid profile and associated parameters, dietary chia increased the concentrations of α-linolenic, eicosapentaenoic, and docosahexaenoic acids and reduced the Σω-6:Σω-3 ratio and the atherogenicity and thrombogenicity indices of the broiler meat. However, the dietary chia seed worsened the feed conversion ratio. Conclusion: Diet containing 2.5% chia oil supplied to broilers during the period from 29 to 42 days of age improves the feed conversion ratio, increases the deposition of the ω-3 fatty acids in the breast and thigh, in addition to reducing the Σω-6:Σω-3 ratio and the atherogenicity and thrombogenicity indices, thereby resulting in meat with higher nutritional quality.

• Journal of Ginseng Research
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• v.38 no.1
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• pp.1-7
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• 2014

Background: Although ginsenosides such as Rg1, Rb1 and Rg3 have shown promise as potential nutraceuticals for cognitive impairment, their use has been limited due to high production cost and low potency. In particular, the process of extracting pure Rg3 from ginseng is laborious and expensive. Methods: We described the methods in preparing ginseol k-g3, an Rg3-enriched fraction, and evaluated its effects on scopolamine-induced memory impairment in mice. Results: Ginseol k-g3 (25-200 mg/kg) significantly reversed scopolamine-induced cognitive impairment in the passive avoidance, but not in Y-maze testing. Ginseol k-g3 (50 and 200 mg/kg) improved escape latency in training trials and increased swimming times within the target zone of the Morris water maze. The effect of ginseol k-g3 on the water maze task was more potent than that of Rg3 or Red ginseng. Acute or subchronic (6 d) treatment of ginseol k-g3 did not alter normal locomotor activity of mice in an open field. Ginseol k-g3 did not inhibit acetylcholinesterase activity, unlike donezepil, an acetylcholinesterase inhibitor. Rg3 enrichment through the ginseol k-g3 fraction enhanced the efficacy of Rg3 in scopolamine-induced memory impairment in mice as demonstrated in the Morris water maze task. Conclusion: The effects of ginseol k-g3 in ameliorating scopolamine-induced memory impairment in the passive avoidance and Morris water maze tests indicate its specific influence on reference or long-term memory. The mechanism underlying the reversal of scopolamine-induced amnesia by ginseol k-g3 is not yet known, but is not related to anticholinesterase-like activity.