• Environmental Engineering Research
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• v.19 no.4
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• pp.363-367
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• 2014

One chambered sediment microbial fuel cell (SMFC) was equipped with Fe, brass (Cu/Zn), Fe/Zn, Cu, Cu/carbon cloth and graphite felt anode. Graphite felt was used as common cathode. The SMFC was membrane-less and mediator-less as well. Order of anodic performance on the basis of power density was Fe/Zn ($6.90Wm^{-2}$) > Fe ($6.03Wm^{-2}$) > Cu/carbon cloth ($2.13Wm^{-2}$) > Cu ($1.13Wm^{-2}$) > brass ($Cu/Zn=0.24Wm^{-2}$) > graphite felt ($0.10Wm^{-2}$). Fe/Zn composite anode have twisted 6.73% more power than Fe alone, Cu/carbon cloth boosted power production by 65%, and brass (Cu/Zn) produced 65% less power than Cu alone. Graphite felt have shown the lowest electricity generation because of its poor galvanic potential. The estuarine sediment served as supplier of oxidants or electron producing microbial flora, which evoked electrons via a complicated direct microbial electron transfer mechanism or making biofilm, respectively. Oxidation reduction was kept to be stationary over time except at the very initial period (mostly for sediment positioning) at anodes. Based on these findings, cost effective and efficient anodic material can be suggested for better SMFC configurations and stimulate towards practical value and application.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.167-171
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• 2002

The resting cells of Candida sp. SY16 produced a large amount of mannosylerythritol lipid as a biosurfactant when incubated in the distilled water containing only the carbon source. The resting cells exhibited the highest production at 20 g cells per liter on the soybean oil of 75 g/1 as a sole substrate and pH 4∼5 in the shaking culture. Under the optimal conditions, the biosurfactant was extracellularly produced to 58 g/1 after 120 h in jar fermentor, and the yield became higher than that obtained by using the glowing cells of the strain in batch fermentation.

• Journal of Microbiology and Biotechnology
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• v.8 no.1
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• pp.61-66
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• 1998

A microorganism which degrades phenol and co-metabolizes trichloroethylene (TCE) was isolated from Yangsan stream after enrichment in a medium containing phenol as the sole carbon source. The isolate EL-43P was identified as the genus Rhodococcus by its morphological, cultural and physiological characteristics. Phenol-induced cells of Rhodococcus sp. EL-43P degraded TCE. Toluene and nutrient broth could not replace the phenol requirement. The optimal conditions of initial pH and temperature of media for growth were 7.0~9.0 and $30~50^{\circ}C$, respectively. Rhodococcus sp. EL-43P could grow with phenol up to 1,000 ppm. Growth was inhibited by phenol at a concentration above 1,500 ppm. It was observed that Rhodococcus sp. EL-43P was able to degrade 90% of phenol (1,000 ppm) after 40 h in a culture. Phenol-induced cells of Rhodococcus sp. EL-43P degraded 95% of $5{\mu}M$ TCE in 6 h. Rhodococcus sp. EL-43P hardly degraded TCE above $100{\mu}M$.

• Journal of Microbiology and Biotechnology
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• v.8 no.1
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• pp.14-20
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• 1998

Syntheses of the B. stearothermophilus xylanolytic enzymes such as xylanases, ${\beta}$-xylosidases, ${\alpha}$-arabinofurano-sidases, and esterases, were observed to be regulated by the carbon source present in the culture media. Xylan induced synthesis of ${\beta}$-xylosidase at the highest level while xylose gave about 30% of the ${\beta}$-xylosidase activity induced by xylan. The lowest syntheses of the xylanolytic enzymes above mentioned were detected in the basal medium containing glucose as a sole carbon source. When a mixture of xylan and glucose was used as a carbon source, we could observe glucose repression of xylanase (about 70-fold) and ${\beta}$-xylosidase (about 40-fold) syntheses. Whereas, the level of the glucose repression of the expression of the xylA gene encoding the major ${\beta}$-xylosidase of B. stearothermophilus was assessed to be about l0-fold when the relative amounts of the xylA transcript were determined. From the sequence of the xylA gene, we could find two CRE-like sequences (CRE-l: nucleotides ＋124 to ＋136 and CRE-2:＋247 to ＋259) within the reading frame of the xylA gene, either or both of which were suspected to be involved in catabolite repression of the xylA gene.

• Journal of Microbiology and Biotechnology
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• v.8 no.4
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• pp.301-304
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• 1998

Methylobacterium organophilum can use nitrogen in the form of ammonium ions ($($NH_4$)_2SO_4\;and\;NH_4Cl) and from nonammonium sources such as glycine, alanine, peptone, and yeast extract. When potassium was limited, significantly more PHB was produced when the ammonium ion was the nitrogen source rather than a nonammonium form. With ammonium, the amount of PHB produced was 0.50-0.53 g PHB/l or $52.0~53.2\%$ of the dry cell weight. If nitrogen was from a nonammonium source, the respective values were 0.04~0.06 g PHB/1 or $8.1~11.3\%$ of dry cell weight. When ammonium sulfate was the sole source of nitrogen under potassium-limited conditions, cell growth and PHB accumulation increased as the pH increased from 6.0 to 7.5. Cell growth and PHB amount at pH 7.5 were 2.50 g dry cell weight/1 and 1.40 g PHB/1, respectively.

• Microbiology and Biotechnology Letters
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• v.15 no.5
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• pp.340-345
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• 1987

Microorganisms capable of utilizing D-xylose as a sole carbon and energy source were isolated to ferment D-xylose directly to ethanol. Among them, the strain, which showed the best ability to pro-duce ethanol, was selected and was identified as Fusarium sp. The optimal conditions for the pro-duction of ethanol were 8.0 of initial pH, 33$^{\circ}C$ of temperature, and 2% of substrate concentration. Under this optimal condition, the following results were obtained : maximum ethanol concentration, 7.0g/$\ell$; ethanol yield, 0.35g of ethanol per g of D-xylose (68.6% of theoretical); biomass yield, 0.27g of dry biomass per g of D-xylose.

• Journal of Astronomy and Space Sciences
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• v.18 no.2
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• pp.145-152
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• 2001

For the research of solar EUV (extreme ultraviolet) radiation, we have designed a small-sifted engineering model of solar EUV telescope, which is suitable for a Korean satellite. The EUV sole. telescope was designed to observe the sun at $584.3AA$(He I) and $629.7AA$(OV) The optical system is an f/8 Ritchey-Chr rien, and the effective diameter and focal length are 80mm and 640mm, respectively. The He I and 0V filters are loaded in a filter wheel. In the detection part, the MCP (Microchannel Plate) type is Z-stack, and the channel-to-diameter radio is 40:1. MCP and CCD are connected by fiber optic taper. A commercial optical design software is used for the analysis of the optical system design.

• Archives of Pharmacal Research
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• v.20 no.4
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• pp.379-383
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• 1997

Cyclosporin A, an potent immunosuppressant, has been known to be one of the modulators of drug resistance as well as a cytostatic drug. Despite many attempts to basic or clinical application of cyclosporin A, there are few reports on the inhibition of brain tumor cells. In the present experiment, the possibility of cyclosporin A as synergic adjuvant was investigated by MTT assay, $[^{3}H]$ thymidine uptake and through flowcytometric anaysis. Sole treatment of cyclosporin A on the CRT and CH235-MG glioma cell line revealed dose dependent cytotoxicity within a range of tested dose. Combined treatment of cyclosporin A with ACNU, BCNU and hydroxyurea on various glioma cancer cell line led to a significant synergistic cytotoxicity as well as inhibition of DNA synthesis with dose-dependency. In addition, cyclosporin A alone or combined treatment caused discernible changes of cell cycle in the tested cells. These data provide that cyclosporin A could potentiate the effect of nitrosourea compounds in vitro on human glioma cells.

• YAKHAK HOEJI
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• v.44 no.6
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• pp.601-606
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• 2000

Recently, studies on missile antitumor drugs, which selectively act on tumor cell and display drug effects, have been performed. These missile antitumor drugs which can increase drug effects and decrease side effects, are ideal medication method. Lectin has been reported as tumor cell specific binding protein and tannin as antitumor substance. In this study, we studied inhibition of melanoma metastasis by lectin-conjugated ellagitannin and used praecoxin A as ellagitannin source. Mouse melanoma cell, B16-F10, was injected into the sole of forefoot of C57BL/6 mouse, and after administration with drug, the number of pulmonary tumor colony was counted. The administration of praecoxin A, lectin-praecoxin A mixiture, and lectin-conjugated praecoxin A was started after amputation of established tumor foci at right forefoot of mice and continued for 3 weeks with i.p. injection of one of those drugs A every 24 hours. Lectin-praecoxin A mixture, and lectin-conjugated praecoxin A significantly reduced the number of spontaneous pulmonary metastasis. Exposure to 5 mg/kg of lectin-praecoxin A mixiture and lectin-conjugated praecoxin A produced a statistically significant 38.3%, 41.8% reduction in the number of remaining pulmonary metastasis. These results suggest that metastasis inhibition by lectin-praecoxin A mixiture and lectin-conjugated praecoxin A are better than that of praecoxin A.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.172-177
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• 2008

Considering the impact of buildings beyond their outline to our environment is the first step towards sustainable architecture. As we are still in the early days of sustainable design and its technology, we should make predictions about the design options. architecture activities in project is needed to predict more locally, nationally, globally not only present but future energy demand. The role of the architects who pioneered sustainable design is significantly important, that is to say architects should become a team leader rather than the sole form-giver and come up with the integrated idea related to each field such as the structural, mechanical and electrical engineers includes an energy specialist, in some cases, an independent Design Facilitator. In other words architects have to suggest goals and alternatives for human-being and biodiversity to sustainable life as well as vision of architecture.