• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.414-420
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• 1993

Escherichia coli mrdAts and mrdBts mutants forming spherical cells at 42C, were employed to investigate the possible role of both inner and outer membrance structures in the determination of cell shape of gram-negative cells. Spherical cells, but not rod-shaped wild types, were specifically killed by anionic detergents, such as sarkosyl, sodium dodecylsulfate and sodium deoxycholate. From the spherical intact cells grown overnight at 42C, much more proteins were released by sakosyl.

• Bulletin of the Korean Chemical Society
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• v.28 no.5
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• pp.873-876
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• 2007

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1811-1814
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• 2008

• Archives of Pharmacal Research
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• v.8 no.4
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• pp.213-220
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• 1985

From olibanum, acetylboswellic acid (I) and boswellic acid (II) were isolated as mixed crystals of $\alpha$-and $\alpha$-forms in the ratio of 1 to 2 and 1 to 4, respectively. And acetyl-11-keto$\beta$-boswellic acid (III) and 11-keto-$\beta$-boswellic acid (IV) were also isolated and their $\alpha$-forms were not found in olibanum by GC/selected ion monitoring MS technique. Contents of four compounds were determined.

• Archives of Pharmacal Research
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• v.8 no.4
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• pp.243-247
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• 1985

A new $\beta$-carboline alkaloid, 1-carbobutoxy-$\beta$-carboline as well as $N_{9}$ -formylharman, 1-carboethoxy-$\beta$-carboline, 1-carbomethoxy-$\beta$- carboline, perloyrine, harman and norharman were isolated from the rhizoma of Polygala tenuifolia Willdenow. The structures were elucidated on the basis of spectroscopic studies and chemical evidence.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.505-508
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• 2008

When it grasps a total property losses and relationship of damage factors, there is possibility of reducing the natural disaster damage which is a yearly repeated. Also, checking and supply to vulnerability should be presupposed. This study aims to find out a damage factor vulnerability using a natural disaster database by Park et al(2007). And added 2005 year data to database. Total 10 damage factors are deaths(person, including missing person) injury(person), victims(person), building(thousand), vessel(thousand), cultivated land(thousand), public facilities(thousand), others(thousand), total property losses(thousand). We analyzed of correlation analysis, ratio, population, area, regional character etc for damage factors.

• Macromolecular Research
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• v.11 no.1
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• pp.36-41
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• 2003

Holographic gratings in two kinds of photopolymers (PPs) were fabricated by optical interference method. Polyvinylalcohol (PVA) and polyvinylacetate (PVAc) were employed as polymer binders and photopolymerization of acrylamide (AA) was confirmed using infrared spectroscopy. Dynamic behavior of the diffraction efficiency was monitored and its temporal stability at room temperature was also observed. Additionally, the temperature dependence of these gratings was investigated in two PPs. The surface topographical change of the photopolymer layer was observed by atomic force microscope (AFM).

• Journal of Korean Society of Water and Wastewater
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• v.35 no.1
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• pp.53-61
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• 2021

The quantified analysis of damages to wastewater treatment plants by natural disasters is essential to maintain the stability of wastewater treatment systems. However, studies on the quantified analysis of natural disaster effects on wastewater treatment systems are very rare. In this study, a total disaster index (DI) was developed to quantify the various damages to wastewater treatment systems from natural disasters using two statistical methods (i.e., AHP: analytic hierarchy process and PCA: principal component analysis). Typhoons, heavy rain, and earthquakes are considered as three major natural disasters for the development of the DI. A total of 15 input variables from public open-source data (e.g., statistical yearbook of wastewater treatment system, meteorological data and financial status in local governments) were used for the development of a DI for 199 wastewater treatment plants in Korea. The total DI was calculated from the weighted sum of the disaster indices of the three natural disasters (i.e., TI for typhoon, RI for heavy rain, and EI for earthquake). The three disaster indices of each natural disaster were determined from four components, such as possibility of occurrence and expected damages. The relative weights of the four components to calculate the disaster indices (TI, RI and EI) for each of the three natural disasters were also determined from AHP. PCA was used to determine the relative weights of the input variables to calculate the four components. The relative weights of TI, RI and EI to calculate total DI were determined as 0.547, 0.306, and 0.147 respectively.

• Food Science of Animal Resources
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• v.44 no.1
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• pp.146-164
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• 2024

Owing to the residual toxicity and adverse health effects of chemical preservatives, there is an increasing demand for using natural preservatives in food. Although many natural extracts have been evaluated, research on their antibacterial effects remains insufficient. Therefore, this study aimed to explore the possibility of developing Psidium guajava, Ecklonia cava, and Paeonia japonica (Makino) Miyabe & Takeda extracts as natural food preservatives. Further, the effect of mixing these extracts on microbial growth and quality was evaluated during the refrigeration of sausages. Optimal mixing ratios were determined based on the minimum inhibitory and bactericidal concentrations of each mixed extract against the Listeria monocytogenes, Salmonella spp. and Escherichia coli. D-optimal mixing design optimization tool was further used to obtain an optimum mixing ratio of Formulation 1 (F1). The antibacterial activity of F1 increased with increasing concentration, with similar activities at 0.5% and 1%. The sausages with synthetic or natural preservatives showed significantly lower lipid oxidation than those of the control and grapefruit extract-treated sausages after 4 wk of refrigeration. Total plate counts were observed only in the control and treatment groups stored for 3 wk, and no significant effect of ascorbic acid was observed. Compared to the other samples, sausages with added natural extracts showed the highest overall acceptability scores initially and after 4 wk. Therefore, similar amounts of grapefruit seed and natural extracts had the same effect on microbiological analysis and lipid rancidity during sausage storage. Hence, this mixture can serve as a potential natural preservative in meat products.

• Bulletin of the Korean Chemical Society
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• v.27 no.3
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• pp.435-438
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• 2006