• Journal of Animal Reproduction and Biotechnology
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• v.38 no.1
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• pp.26-31
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• 2023

Chicken embryonic stem (ES) cells have great potential and provide a powerful tool to investigate embryonic development and to manipulate genetic modification in a genome. However, very limited studies are available on the functional characterization and robust expansion of chicken ES cells compared to other species. Here, we have developed a method to generate chicken embryonic stem cell-like cells under pluripotent culture conditions. The chicken embryonic stem cell-like cells were cultivated long-term over several passages of culture without loss of pluripotency in vitro and had the specific expression of key stem cell markers. Furthermore, they showed severe changes in morphology and a significant reduction in pluripotent genes after siRNA-mediated NANOG knockdown. Collectively, these results demonstrate the efficient generation of chicken embryonic stem cell-like cells from EGK stage X blastoderm-derived singularized cells and will facilitate their potential use for various purposes, such as biobanking genetic materials and understanding stemness in the fields of animal biotechnology.

• Journal of the Korean Home Economics Association
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• v.39 no.4
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• pp.1-18
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• 2001

Korea huts been dramatically changed during the last century in many aspect of society, with the introduction of western culture in the beginning of 20th century. This study aims at understanding the changes in our traditional culture shown by costume as well as examining the aspects of the changes of traditional clothing according to age, by comparing the differences of our traditional dress Hanbok between ear1y and the late of the 20th century. Analysis of photographs showing Hanbok of both ages was used. 155 photographs of people wearing traditional Hanbok in the beginning of the 20th century were collected from the photo collection books portraying various living conditions of common people at that time. 748 Photographs of Hanbok worm today were obtained by taking pictures of various occasions like wedding ceremonies in 5 big cities during 1997. The process of analysis consists of 3 stages: setting standards, sorting, and grouping by positioning. The results showed that traditional Hanbok room in the early 20th century has maintained its basic silhouette and design during the century, but the methods of color coordination, ornamentation, construction have underdone many changes in detail. Consequently, traditional frame exits, but actually there are many variations of tradition produced by individual tastes and fashion trend. These changes show that continuing influx of the western culture which has made enormous social changes in Korea had an influence even on Hanbok.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1369-1378
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• 2007

For effective exopolysaccharide production and mycelial growth by a liquid culture of Fomitopsis pinicola in an air-lift bioreactor, the culture temperature, pH, carbon source, nitrogen source, and mineral source were initially investigated in a flask. The optimal temperature and pH for mycelial growth and exopolysaccharide production were $25^{\circ}C$ and 6.0, respectively. Among the various carbon sources tested, glucose was found to be the most suitable carbon source. In particular, the maximum mycelial growth and exopolysaccharide production were achieved in 4% glucose. The best nitrogen sources were yeast extract and malt extract. The optimal concentrations of yeast extract and malt extract were 0.5 and 0.1%, respectively. $K_2HPO_4\;and\;MgSO_4{\cdot}7H_2O$ were found to be the best mineral sources for mycelial growth and exopolysaccharide production. In order to investigate the effect of aeration on mycelial growth and exopolysaccharide production in an air-lift bioreactor, various aerations were tested for 8 days. The maximum mycelial growth and exopolysaccharide production were 7.9 g/l and 2.6 g/l, respectively, at 1.5 vvm of aeration. In addition, a batch culture in an air-lift bioreactor was carried out for 11 days under the optimal conditions. The maximum mycelial growth was 10.4 g/l, which was approximately 1.7-fold higher than that of basal medium. The exopolysaccharide production was increased with increased culture time. The maximum concentration of exopolysaccharide was 4.4 g/l, which was about 3.3-fold higher than that of basal medium. These results indicate that exopolysaccharide production increased in parallel with the growth of mycelium, and also show that product formation is associated with mycelial growth. The developed model in an air-lift bioreactor showed good agreement with experimental data and simulated results on mycelial growth and exopolysaccharide production in the culture of F. pinicola.

• Journal of the Korean Institute of Rural Architecture
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• v.5 no.1
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• pp.32-41
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• 2003

After the 1988 Seoul Olympics, a lot of Culture & Arts Centers have been built in Korea. There have been raised questions on the frequency of room use and the occupancy of seats, but there are not enough architectural data for the Culture & Arts Centers in Korea. This paper focuses on the investigation of the architectural features of the Culture & Art Centers, such as the spatial sizes, the composition ratio of the performing art hall area to the overall facility area, the sizes and proportions of seat zone to stage zone, the average area per one person at the seat zone, the wide and the height of the procenium, the height of fly loft, and the number of users per one program. We could find out some meaning results. The composition ratios of the performing art hall area to the overall area of the facilities distribute with a wide range. The floor areas of 1500 through 2000 seat performing art halls are larger than $13,000m^2$. The average area per one person for seat zone and stage zone is approximately $0.8m^2$. All facilities we investigated have the types of the procenium stage. Almost all of the facilities have high quality stage conditions and equipments, but few programs use the various stage equipments and all of the main, side, and rear stages. To resolve this problems, various programs have to be developed for encouraging more people to use the Culture & Art Centers.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.583-587
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• 1992

This study was conducted in order to optimize the media composition and cultural conditions for kasugamycin production by Streptomyces kasugaensis. The optimum culture conditions are pH 6.6 (before sterilization) and $28^{\circ}C$ for the production of kasugamycin. The kasugamycin concentration was not increased when silicone oil as antifoam agent was added. The addition of water during the cultivation in the various media showed a positive effect for the production of kasugamycin.

• Environmental Engineering Research
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• v.20 no.2
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• pp.121-125
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• 2015

Biohydrogen production from food waste via dark fermentation was conducted by using mixed culture under various environmental conditions (initial pH, initial F/M ratio, initial ferrous iron ($Fe^{2+}$), and temperature condition) in batch reactor. The results revealed that the maximum hydrogen yield of $46.19mL\;H_2/g\;COD_{add}$ was achieved at the optimal conditions (initial pH 8.0, initial F/M ratio 4.0, initial iron concentration 100 mg $FeSO_4/L$ and thermophilic condition ($55{\pm}1^{\circ}C$)). Furthermore, major volatile fatty acid (VFA) productions of butyrate (765.66 mg/L) and acetate (324.69 mg/L) were detected and COD removal efficiency was detected at 66.00%. Therefore, these optimal conditions could be recommended to operate a system.

• Animal Bioscience
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• v.34 no.8
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• pp.1392-1402
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• 2021

Objective: The growth rate of pigs is related to differentiation and proliferation of muscle cells, which are regulated by growth factors and expression of growth-related genes. Thus, the objective of this study was to establish optimal culture conditions for Jeju black pig (JBP) muscle cells and determine the relationship of various factors involved in muscle growth with the proliferation of JBP muscle cells. Methods: Muscles were taken from the femur skeletal muscle of JBP embryos. After isolation of the muscle cells, cells were cultured in a 6-well plate under four different culture conditions to optimize culture conditions for JBP muscle cells. To analyze proliferation rate of JBP muscle cells, these muscle cells were seeded into 6-well plates at a density of 1.5×10⁵ cells per well and cultured for 3 days. Western blot and quantitative real-time polymerase chain reaction were applied to verify the myogenic differentiation 1 (MyoD) expression and growth-related gene expression in JBP muscle cells, respectively. Results: We established a muscle cell line from JBP embryos and optimized its culture conditions. These muscle cells were positive for MyoD, but not for paired box 7. The proliferation rate of these muscle cells was significantly higher in a culture medium containing bFGF and epidermal growth factor + basic fibroblast growth factor (EGF+bFGF) than that without a growth factor or containing EGF alone. Treatment with EGF and bFGF significantly induced the expression of MyoD protein, an important transcription factor in muscle cells. Moreover, we checked the changes of expression of growth-related genes in JBP muscle cells by presence or absence of growth factors. Expression level of collagen type XXI alpha 1 gene was changed only when EGF and bFGF were added together to culture media for JBP muscle cells. Conclusion: Concurrent use of EGF and bFGF increased the expression of MyoD protein, thus regulating the proliferation of JBP muscle cells and the expression of growth-related genes.

• Journal of Life Science
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• v.13 no.5
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• pp.618-625
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• 2003

Investigations were carried out to optimize the culture conditions for the production of xylanase by Paenibacillus sp. DG-22, a moderately thermophilic bacterium isolated from timber yard soil. Xylanase production showed a cell growth associated profile. Xylanase activity was found only in the culture supernatant, while $\beta-xylosidase$ activity was mainly associated with the cells. The formation of xylanase activity was induced by xylan and repressed by glucose and xylose. The production profile of xylanase was examined with various commercial xylan and maximum yield was achieved with 0.1∼ 0.5% birchwood xylan. Among various nitrogen sources tested, yeast extract was optimal for the production of xylanase. The xylanase activity was inhibited by $Co^{2+},\; Cu^{2+},\; Fe^{3+},\; Hg^{2+}\;$ and$\;Mn^{2+}$ ions while $Ca^{2+},\; Mg^{2+},\; Ni^{2+},\; Zn^{2+}$ions and DTT stimulated xylanase activity Mercury (II) ion at 5 mM concentration abolished all the xylanase activity. The predominant products of xylan-hydrolysate were xylobiose, xylotriose, and higher xylooligo-saccharides, indicating that the enzyme was an endoxylanase.

• Journal of Microbiology and Biotechnology
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• v.31 no.12
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• pp.1624-1631
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• 2021

Prodigiosin as a high-valued compound, which is a microbial secondary metabolite, has the potential for antioxidant and anticancer effects. However, the large-scale production of functionally active Hahella chejuensis-derived prodigiosin by fermentation in a cost-effective manner has yet to be achieved. In the present study, we established carbon source-optimized medium conditions, as well as a procedure for producing prodigiosin by fermentation by culturing H. chejuensis using 10 L and 200 L bioreactors. Our results showed that prodigiosin productivity using 250 ml flasks was higher in the presence of glucose than other carbon sources, including mannose, sucrose, galactose, and fructose, and could be scaled up to 10 L and 200 L batches. Productivity in the glucose (2.5 g/l) culture while maintaining the medium at pH 6.89 during 10 days of cultivation in the 200 L bioreactor was measured and increased more than productivity in the basal culture medium in the absence of glucose. Prodigiosin production from 10 L and 200 L fermentation cultures of H. chejuensis was confirmed by high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) analyses for more accurate identification. Finally, the anticancer activity of crude extracted prodigiosin against human cancerous leukemia THP-1 cells was evaluated and confirmed at various concentrations. Conclusively, we demonstrate that culture conditions for H. chejuensis using a bioreactor with various parameters and ethanol-based extraction procedures were optimized to mass-produce the marine bacterium-derived high purity prodigiosin associated with anti-cancer activity.

• Food Science and Preservation
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• v.11 no.3
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• pp.405-410
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• 2004

Leuconostoc mesenteroides subsp. cremoris DLAB19 were investigated under various culture conditions to maximize the production of antimutagenic substance(s) against aflatoxin Bl(AFBl) on Salmonella enterica serovar Typhimurium TAI00 and TA98. The MRS medium containing glucose(2$\%$) as a carbon source and yeast extract(1 $\%$) as a nitrogen source resulted in the highest production of the antimutagenic substance(s) against aflatoxin Bl(AFBl) in the culture supernatant of Leu. mesenteroides subsp. cremoris DLAB19. Optimal pH of the medium, culture temperature and shaking speed for the antimutagenic substance(s) production were pH 7.0, 30$^{\circ}C$ and 150 rpm, respectively. Under the optimal condition, the antimutagenic effects of Leu. mesenteroides subsp. cremoris DLAB19 culture supernatant were 87.11 $\%$ on S. enterica serovar Typhimurium TA100 and 75.04 S. enterica serovar Typhimurium TA98.