• Environmental Engineering Research
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• 제18권4호
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• pp.277-281
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• 2013

A dual-chamber microbial fuel cell (MFC) inoculated with Desulfovibrio desulfuricans and supplemented with lactate as an organic fuel was employed in this study. Biofilm formed on the anodic electrode was examined by scanning electron microscopy, revealing that the amount of biofilm was increased with repeated cycles of MFC operation. The maximum current production was notably increased from the first cycle ($1,310.0{\pm}22.3mA/m^2$) to the final cycle ($1,539.4{\pm}25.8mA/m^2$) of MFC run. Coulombic efficiency was also increased from $89.4%{\pm}0.2%$ to $98.9%{\pm}0.5%$. We suggest that the current production efficiency was related to the biomass of biofilm formed on the electrode, which was also increased as the MFC run was repeated. It was also found that D. desulfuricans, which colonized on the electrode, produced filaments or nano-pili. Nano-pili were effective for the attachment of cells on the electrode. In addition, the nano-pili provided a cell-to-cell link and stimulated the development of thicker electroactive biofilm, and therefore, they facilitated electron transfer to the anode. Conclusively, the biofilm of D. desulfuricans enhanced the current production in the MFC as a result of effective attachment of cells and electron transfer from the cell network to the electrode.

• Journal of Acupuncture Research
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• 제35권4호
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• pp.182-186
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• 2018

Background: The purpose of this study was to investigate the effects of wild ginseng pharmacopuncture on melanin production in B16/F10 murine melanoma cells. Methods: To determine the effect of wild ginseng pharmacopuncture solution on B16/F10 cells, cytotoxicity was evaluated using the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl-tetrazolium bromide (MTT) method. To observe B16/F10 cell growth, death, and morphological changes, Trypan blue solution was used. The Hosoi method was used to investigate the effect of wild ginseng pharmacopuncture solution on melanin production. The Martinez-Esparza method was used to investigate the effect of wild ginseng pharmacopuncture solution on tyrosinase activity. To determine the pathway involved in the melanogenesis in cells exposed to wild ginseng pharmacopuncture solution, a cell-free tyrosinase was used. Results: Following treatment with $200{\mu}L$ of wild ginseng solution, the cell survival rate was $76.32{\pm}2.45%$ which significantly decreased with higher concentrations (${\mu}L$) of wild ginseng (up to $200{\mu}L$). When $100{\mu}L$ of wild ginseng was used, the cell survival rate was $89.95{\pm}2.07%$. No morphological changes or abnormalities were observed in the B16/F10 murine melanoma cells as observed in the Trypan blue test. Melanin production was significantly reduced to $72.17{\pm}3.74%$ at $100{\mu}L$. Using $100{\mu}L$ of wild ginseng solution, tyrosinase activity was significantly decreased to $80.15{\pm}1.05%$. Wild ginseng pharmacopuncture solution reduced melanin production both directly and indirectly. Conclusion: This study suggests that wild ginseng pharmacopuncture solution may be effective in inhibiting melanin production. Further studies are needed to determine safe and effective clinical applications.

• 미생물학회지
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• 제23권4호
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• pp.259-264
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• 1985

Aspergillus parasiticus의 발육과 afla toxin생산에 미치는 생약 extract의 효과에 따라 선정된 생약 금은화, 우방자 및 인삼의 조 saponm이 군체의 발육과 afla toxin생산능력에 미치는 효과을 측정하기 위하여 강화배지에 $30^{\circ}C$ 9 일간 배양하였다. 백삼 saponin 첨가배지 만이 균체발율이 대조군 보다 좋았다. 그러나 홍삼 saponin 0.36% 첨가배지에서의 균체발육은 대조군의 62.3%로 나타났으나, aflatoxin 생산능력은 aflatoxin B, 이 대조군의 38.7%. aflatoxin G1 이 22.9%로 좋은 억제효과를 나타냈다. 우방자 sapollln은 홍삼 saponin보다 억세효과가 못하지만 홍삼 saponin과 같이 균체의 발육과 aflatoxin 생산을 모두 억제 하는 것으로 나타났다. 한편 extract 에서 나타났던 금은화의 aflatoxin 생산 억제효과는 본 saponin 실험에서는 나타나지 않았다.

• International Journal of Industrial Entomology and Biomaterials
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• 제3권1호
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• pp.105-108
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• 2001

The wild entomopathogenic fungi, Cordyceps militaris, were collected at the Whawang mountain, Korea. The pupae of the silkworm, Bombyx mori, were used as infecting hosts for the production of the silkworm-mili-taris dongchunhacho, silkworm vegetable wasps and plant worms with C. militaris. Three inoculation methods in terms of injection, spray and immersion were tested against the silkworm pupae. The three inocu1ation methods revealed 100% infectivity to the silkworm pupae tested. Of the three inoculation methods, the injection method was highly effective in the reduction of the period required for the endosclerotium and the completion of fruiting body formation. These results indicate that the silkworm pupae are very effective host insects for the production of C. militaris.

• 한국미생물·생명공학회지
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• 제28권1호
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• pp.33-38
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• 2000

In order to produce ascorbic acid-2-phosphate from ascorbic acid, bacteria capable of transforming ascorbic acid to ascorbic acid-2-phosphate were isolated from soils and the stock cultures in our laboratory. Among them, a newly isolated bacterium LSH-3 having the best ability of producing ascorbic acid-2-phosphate was selected and partially identified as Pseudomonas sp. The optimum conditions for the production of ascorbic acid-2-phosphate from ascorbic acid and using its resting cells as the source os enzyme were investigated. The results were summarized as follows: The optimum cultivation time and the cell weight for the production of ascorbic acid-2-phosphate was 14 hours and 100g/I(wet weight), respectively. And 0.1%(v/v) Trition X-100 was the most effective surfactant. The optimum concentrations of ascorbic acid and pyrophosphate were 400mM and 500mM, respectively, which led to produce 14.54g/I of ascorbic acid-2-phosphate. The most effective buffer was 50mM sodium acetate. The optimum pH and temperature were 4.5 and $40^{\circ}C$, respectively. Under the above conditions, 17.71 g/I of ascorbic acid-2-phosphate was produced from ascorbic acid after 32 hour-incubation, which corresponded to 17.5% of conversion rate based on ascorbic acid.

• 한국토양비료학회지
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• 제48권2호
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• pp.94-99
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• 2015

The performance of chamber and bag digesters for solid state anaerobic digestion (SS-AD) of separated solid fraction of swine manure was investigated using lab-scale digester (4,460 mL total volume and 1,800 mL of effective volume) operating at $37^{\circ}C$ for 63 days. The performance of two different digester types was evaluated in terms of the kinetic constants of methane production obtained from the Gompertz and Gaussian equations. Methane production potential of chamber and bag digester was 202 and $218N{\cdot}mL$ $CH_4/g$ VS. Time to produce 95% methane production potential (T95) and calculated effective anaerobic digestion time were 55.5 days and 41.8 days for chamber digester and 52.8 days and 43.5 days for bag digester, respectively. Our results reveal that the performance was not significantly different between chamber and bag digester.

• 한국전산유체공학회지
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• 제21권3호
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• pp.110-117
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• 2016

It is a essential to minimize production of by-products for economically effective petrochemical process. In order to find key factor to achieve the effective process, 2-dimensional computational fluid dynamics considering a variety of physics such as convective and radiative heat transfer and thermal cracking of ethane are carried out. The reactor is modeled as an isothermal tube, whose length is 1.2 m and radius is 0.01 m, respectively. At first, the axial distribution of representative by-products in ethane thermal cracking are investigated in each inner wall temperature conditions. Then the comparison between concentration of propene($C_3H_6$) and ethane conversion is discussed with respect to inner wall temperature conditions too. Finally, both reaction rate and turbulent kinetic energy are used to identify the production mechanism of $C_3H_6$ under the intersection point in the plot for $C_3H_6$ molar concentration and ethane conversion.

• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.303-310
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• 1999

A cost-effective mass production method for a strong antimicrobial peptide, buforin II, which was isolated from the stomach of Bufo bufo gargarizans, has been developed. This method is based on the neutralization of the positive charge of buforin II by fusion with a cysteine-rich acidic peptide (CAP) to avoid any lethal effect on the host. The neutralized fusion peptide was multimerized and expressed in Escherichia coli as tandem repeats to increase the production yield. Multimers of the CAP-buforin II fusion peptide were successfully expressed at high levels in E. coli as inclusion bodies. More than 100mg of pure buforin II was obtained per 11 of E. coli culture after cleaving the multimeric polypeptide with CNBr. The buforin II obtained from the recombinant E. coli had antimicrobial activity identical to that of natural buforin II. The proposed expression system can provide a cost-effective mass production method for both antimicrobial peptides and other host-lethal basic proteins.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.447-452
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• 1994

The strain SL-387 which produces new inhibitors of aminopeptidase M, MR-387A and B, was isolated from a soil sample. The strain has branched substrate mycelia, from which aerial hyphae develop in the form of open spirals. Spore surface is smooth. Melanoid and soluble pigme- nts were observed. The isolate contains LL-diaminopimelic acid in its cell wall hydrolysate, and has no pectinolytic activity. The strain SL-387 is closely related to Streptomyces griseoruber and S. naganishii, but is different from these strains in some cultural and physiological characteristics. This strain was, therefore, designated as Streptomyces sp. SL-387. The effects of several carbon and nitrogen sources on the production of the inhibitor were examined. Among them, glucose, galactose, mannose, and xylose were effective as a carbon source and soybean meal, soytone, fish meal, and gluten meal were effective as a nitrogen source. The maximum peak of the inhibitor production in jar fermentor was obtained on the fifth day of culture.

• 생약학회지
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• 제16권3호
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• pp.171-174
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• 1985

Panax ginseng root has been widely used as an important drug for thousands years in China, Korea and Japan. The main effective components of ginseng have been believed to be saponins. However, ginseng cultivation is very difficult and needs many years for growth. It has already been shown that Panax ginseng callus produces a considerable amount of the same kinds of saponins as in intact plants. Various culture conditions were examined for increased production of ginseng saponins by cell culture. The saponin contents and the growth rates in two cell lines of ginseng callus were compared in static and suspension cultures, rotary and reciprocal shaking cultures. It was shown that the growth rate in rotary shaking cultures of D5-B2K-B2K callus was the highest and ginseng saponin production was most effective in reciprocal cultures of D5-B2K-B2K callus. The saponin content per fresh weight of the culture was 1.03 times higher than that of the fresh ginseng root.