• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.1
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• pp.1-6
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• 1994

Some physicochemical properties of sugary rices were comparatively analyzed with the original cultivars, using Hwachung su-1, su-2, and Nampung su lines bred in Seoul Nat'l Univ., and EM 5 bred in Kyushu Univ. Sugary rice grains were smaller in width and thickness, and the relative dry weight of 1000 grains of sugary rices ranged from 49% to 72%, compared to normal ones. No distinct starch granules were found in endosperm of sugary rices exposured by SEM, with structural variations between Hwachung su-1 and su-2 lines. Sugary rices showed the significant increases in sucrose, glucose and fructose content, especially much higher in sucrose content showing 5.84-8.79%, in comparison with the normal ones, 1.11∼2.65%. However, sucrose and total sugar content varied within sugary lines carrying the same sugary gene, and were significantly lower in Hwachung su-2. Sugary rices, except Hwachung su-1, showed the same or lower ADV and harder gel characteristics, compared to normal ones. Protein and lipid content were much higher in sugary rices, due to the increased relative proportion of aleurone layer in brown rice caused by thicker aleurone layer than in normal rices and the reduction of endosperm part. However, there were no remarkable changes in amino acid and fatty acid compositions.

• Korean Journal of Microbiology
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• v.50 no.1
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• pp.40-45
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• 2014

In order to increase the persistence of plant growth promoting rhizobacteria (PGPR) in rhizpsphere soil, the growth of tomato was examined after the application of Arthrobacter woluwensis ED immobilized in alginate bead, which was known as PGPR. When tomato seedlings were treated with A. woluwensis ED of $1{\times}10^6$ cells g $soil^{-1}$ and incubated for 30 days in a plant growth chamber, the shoot length, root length, fresh weight and dry weight of the grown tomato plants treated with the suspended inoculants significantly increased by 36.2, 59, 51.1, and 37.5%, respectively compared to those of the uninoculated control. The treatment of the immobilized bacteria increased those by 42, 67.4, 62.5, and 60.4%, respectively compared to those of the uninoculated control. Therefore, the enhancement of tomato growth by the treatment of the immobilized bacteria was higher than those by the suspended inoculants. The effects of the inoculation on indigenous bacterial community and the fate of the inoculated bacteria were monitored by denaturing gradient gel electrophoresis analysis. The DNA band intensity of A. woluwensis ED in the tomato rhizosphere treated with the suspended inoculants continuously decreased after the inoculation, but the band intensity in the tomato rhizosphere soils treated with the immobilized inoculants showed the maximum at 1 week after inoculation and the decreasing rate was less than that of the suspended inoculants, which indicated the longer maintenance of the immobilized bacteria at rhizosphere soils. Therefore, encapsulation of PGPR in alginate beads may be more effective than liquid inoculant for the plant growth promotion and survival of PGPR at plant rhizosphere.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.78-86
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• 2006

Laminarans with different purity were prepared from Eisenia bicyclis and their structures were characterized. Crude laminaran was successively extracted two times at room temperature for 2 hr with 0.09 N HCl, and partially purified laminaran was isolated using cetylpyridinium chloride (CPC). Crude laminaran accounted for $14.5\%$ of the dry seaweed weight and contained $8.4\%$ protein, $7.6\%$ sulfate and $68.2\%$ polysaccharide. Partially purified laminaran accounted for $6.5\%$ of the dry algal weight and composed of $3.8\%$ protein, $3.2\%$ sulfate and $74.7\%$ total sugar, which is mainly composed of glucose $(83.3\%)$, indicating that partially purified laminaran was more purified polysaccharide than crude laminaran. Purified laminaran was fractionated into one fractions by Sephacryl S-300 HR column chromatography and this fraction was analysed by FT-IR, $^{13}C$ NMR, methylation and gel filtration chromatography. Purified laminaran showed $\beta-configuration$ $(^{13}C:103.0ppm,\;FT-IR:888cm^{-1})$ in the anomerization of the glycosidic linkages and was $(1\rightarrow3),\;(1\rightarrow6)$ linked $\beta-glucan$. The average molecular weight of purified laminaran was 12,600 dalton.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.97-103
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• 2016

This study was conducted for the production of water-soluble dietary fiber (SDF) from buckwheat hulls by using Celluclast or Viscozyme. The functionality of this SDF, including antioxidant activity, glucose- and bile acid-retardation effects in vitro, was measured. SDF yields from cellulose and hemicellulose fractions were 60.5 and 123.7 g/kg dry matter, respectively. Analysis of molecular weight distribution of SDF by using gel chromatography showed that SDF degradation increased with increase in reaction time. The antioxidant activity of SDF obtained by enzymatic hydrolysis was higher than that of dietary fiber without enzyme treatment. SDF showed higher retardation effects on glucose and bile acid than the sample without dietary fiber did. The results of this study suggested that SDF produced from buckwheat hull by enzymatic hydrolysis is a good source of functional food material because of its high antioxidant activity and glucose- and bile acid-retardation effects.

• Journal of Radiation Protection and Research
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• v.18 no.1
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• pp.25-35
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• 1993

To develop a technique of theoretical alpha track density calculation for comparison with measured track density, an electrostatic ion spectrometer was specially designed and fabricated. The mobility spectrum of first radon daughter(Po-218) in the range of $0.07{\sim}5.0cm^2/V\;s$ from the radon chamber was measured using-the electrostatic ion spectrometer. Measurement was taken in a radon chamber operated using dry particle free air passed through silica gel, activated charcoal and molecular sieve filters. The mobility of a new-born Po-218 ion measured by the electrostatic ion spectrometer was determined to be $1.92cm^2/V\;s$. A comparison of the theoretical and measured alpha track densities was completed and uncertainties concerning the shape of the spectrum were analyzed. It was found that the discrepancies in track densities are primarily Que to the neglect of wall loss of ions in the theoretical track density calculation.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.132-136
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• 1998

Molecular analyses of natural microbial communities are often dependent upon the obtainments of pure nucleic acids. The four methods (elution after agarose gel electrophoresis, G-75 microspin columns, hydroxyapatite mi-crospin columns, and polyvinylpolypyrrolidone (PVPP) microspin columns) were compared for the removal of PCR-inhibitory humic substances from the crude DNA extracts of marine sediment samples. The PVPP microspin columns have shown superior removal of humic substances from the crude DNA extract of marine sediment samples, with yield of $4.8{\mu}g/g$ (dry weight of sediment). The purified DNA by this rapid method was pure enough to amplify 1.5 kb fragment corresponding almost full length of 16S rRNA genes.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.127-134
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• 2011

The purpose of this study was to purify antioxidant substances from steamed squid extract (SSE). The yield of SSE was 8% by dry weight. The approximate compositions of SSE proteins, lipids, moisture, carbohydrate and ash were 64.95%, 1.69%, 7.23%, 4.44% and 21.69%, respectively. The major amino acids in SSE were taurine (29.17%), glycine (20.33%), alanine (12.51%), and glutamic acid (9.83%). Antioxidant activities were evaluated using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, which was measured as 24.7% at 1.0 mg/mL. Four SSE fractions were isolated by Sephadex G-25 gel chromatography; the F2 fraction showed the highest DPPH radical scavenging activity. The F2 fraction was separated by reverse-phase high performance liquid chromatography (HPLC) using an octadecylsilane (ODS) column, yielding a purified antioxidant substance with a DPPH radical scavenging activity of 64.41% at 1.0 mg/mL, representing a 2.64-fold increase in the scavenging activity of SSE purified by the 3-step procedure. The amino acid compositions showed that purified SSE was rich in taurine, glycine, glutamic acid and alanine. The purified SSE significantly elevated 2',7'-dichlorodihydrofluororescein diacetate (DCFH-DA) fluorescence probe, which confirms its effective radical scavenging potential in cellular ROS. In addition, the SSE significantly inhibited oxidative damage of purified genomic DNA. These results suggest that a purified antioxidant substance from SSE can be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.288-288
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• 2013

We report the catalytic activity of Au/$TiO_2$ and Pt/$TiO_2$ nanocatalysts under CO oxidation fabricated by arc plasma deposition (APD), which is a facile dry process with no organic materials involved. Using APD, the catalyst nanoparticles were well dispersed on $TiO_2$ powder with an average particle size (2~4 nm) well below that of nanoparticles prepared by the sol-gel method (10 nm). We found that the average particle size of the dispersed gold nanoparticles can be controlled by changing the plasma discharge voltage of APD. Accordingly, the amount of loaded gold on the $TiO_2$ powder increased with increasing discharge voltage, but the specific surface area of the Au/$TiO_2$ samples decreased. As for catalytic reactivity, Au/$TiO_2$ showed a higher catalytic activity than Pt/$TiO_2$ in CO oxidation. The catalytic activity of the Au/$TiO_2$ samples showed size dependence where higher catalytic activity occurred on smaller gold nanoparticles. The study suggests that APD is a simple way to fabricate catalytically active nanocatalysts.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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• pp.21-28
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• 2007

The crude biopolymer (AS-S1) and endobiopolymer (AS-S2) were isolated from the dry stem bark of Acanthopanax sessiliflorus and tested for anti complement activity. The two potent anticomplement biopolymers, AS-1 and AS-2-Fr.I, were isolated by the combination of ion-exchange chromatography and gel filtration methods from the endo-biopolymers (AS-S2). The anticomplement activity of AS-1 (MW 12 kDa) and AS-2-Fr.I (MW 180 kDa) were found to be 84.4% and 100.0%, respectively, at the concentration of $25{\mu}g/ml$. Activated pathway of the complement system occurred in both classical and alternative pathways, as evidenced by crossed immunoelectrophoresis(CIEP), where a major pathway was detected to be the classical one. It was found that the anticomplement activities of the periodate oxidized were decreased significantly, but those of pronase digested biopolymers of AS-1 and AS-2-Fr.I were decreased very little. The AS-1 contained 2,4,6-tri-O-methyl-D-glucitol, 2,3,6-tri-O-methyl-D-galacitol, and 2,3,6-tri-O-methyl-D-galacitol, which indicated that AS-1 contained a $(1{\rightarrow}3),\;(1{\rightarrow}4)-linked$ glucopyranosyl residue and a $(1{\rightarrow}4)-linked$ galactosyl residue. AS-2-Fr.I contained mainly 2,4-di-O-methyl-D-mannitol and 2,3,4-tri-O-methyl-D-galacitol, which contained $(1{\rightarrow}3),\;(1{\rightarrow}6)$ linked mannosyl and $(1{\rightarrow}6)$ linked galactosyl residues.

• Korean Journal Plant Pathology
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• v.1 no.3
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• pp.190-194
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• 1985

The insect vector (Laodelphax striatellus) of rice black-streaked dwarf virus prefered rice plant to maize in feeding both in the cage and in the field, whereas the percent of infectious plants was much higher in maize than rice plants. The causal virus reduced the adult longevity, total number of hatching nymphs and maturity rate from nymphs of the insect vector. The percent of dry weight over fresh weight in rice from early to late growth stages was lower in diseased plants than in healthy plants but it was reversed on maize plant in early growth stage. In agarose gel-diffusion and microprecipitin serological tests, the intensities of antigen with antisera were in orders the preparation partially purified from infected maize leaves> rice stems> rice leaves> maize stems. The pholem galls in diseased plants developed well in the low temperature.