• Applied Biological Chemistry
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• v.46 no.3
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• pp.251-256
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• 2003

The polyphenol fractions of Korean ginseng were purified using Sephadex LH-20, MCI gel, Bondapak $C_{18}$ TLC, and HPLC from the 60% acetone soluble fraction. Fraction I showed 48.16%, 79.71% and 43.55% inhibition at 150 ppm against lipid oxidation in the presence of copper ion, superoxide and hydrogen peroxidation. Electron donating abilities of fraction II showed 35.17% inhibition at 200 ppm. Fraction III showed 48.49% and 25% inhibition at 150 ppm against lipid oxidation in the presence of ferrous ion and hydroxy radical ion. The phospholipase $A_2$ inhibitory effect of fraction III was 48.9% at the concentration of $60\;{\mu}g/ml$. The cytotoxic effects of fraction II was the highest (73.29% at 0.25 mg/ml) among the tested polyphenol fractions.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.330-337
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• 1990

The crude polysaccharide from Panax ginseng prepared by hot water extration and precipiation with ethanol was further fractionated into neutral and acidic fractions by DEAE- cellulose ion exchange chromatography. The chemical compositions were 85.0% carbohydrorate and 15.0% protein for the neutral fraction, and 28.4% carbohydrate, 10.0% protein and 29.0% uronic acid for the acidic fraction. The acidic fraction was more effective in increasing of the ratio of spleen to body weight, the number of antibody secreting cells to SRBC and phagocytic activity of reticuloendothelial system, as well as antitumor activity against the solid form of sarcoma 180 in ICR mice than the neutral fraction. All polysaccharide fractions were mitogenic to cultured spleen cells of C57BL/6 mice. However, FA was different from FN in the co-mitogenicities with lectin mitogens. Both crude and acidic fractions potentiated remarkably the mitogenic activity of PHA-P or LPS in dose-dependent manner but neutral fraction enhanced only that of LPS. Three polysaccharide fractions had no effect on that of Con A. These results suggest that the acidic fraction may stimulate B and Td cells as well as macrophages while the neutral fraction may simulate only B cells and macropages.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1199-1204
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• 2013

Nanocomposites consisting of Sn nanoparticles and graphene oxide (GO) were electrophoretically deposited onto Cu current collectors that was used for anodes in Li ion batteries (LIBs). In order to optimize the electrochemical performance of nanocomposites as an anode material by controlling the oxygen functionality, the GO was subjected to $O_3$ treatment prior to electrophoretic deposition (EPD). During thermal reduction of the GO in the nanocomposites, the Sn nanoparticles were reduced in size, along with the formation of SnO and/or $SnO_2$ at a small fraction, relying on the oxygen functionalities of the GO. The variation in the duration of time for the $O_3$ irradiation resulted in a small change in total oxygen content, but in a significantly different fraction of each functional group in the GO, which influenced the Sn nanoparticle size and the amount of SnO (and/or $SnO_2$). As a result, the EPD films prepared with the GO that possessed the least amount of carboxylic groups (made by treating GO in an $O_3$ environment for 3 h) showed the best performance, when compared with the nanocomposites composed of untreated GO or GO that was $O_3$-treated for a duration of less than 3 h.

• KSBB Journal
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• v.25 no.5
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• pp.459-465
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• 2010

A simple and efficient analytical method for the simultaneous determination of seven tar color additives was developed using ion pair high performance liquid chromatography. The conditions for HPLC analysis were as follows: column, ${\mu}$-Bondapak C18 (10 ${\mu}m$, 300 ${\times}$ 3.9 mm i.d.); gradient mobile phase, 0.025 mol/L ammonium acetate (containing 0.01 mol/L tetrabutylammonium bromide)-acetonitrile-methanol (65:25:10) as a mobile for fraction A and 0.025 mol/L ammonium acetate (containing 0.01 mol/L tetrabutylammonium bromide)-acetonitrilemethanol (40:50:10) as a mobile for fraction B; flow rate, 1.0 mL/ min; detection wavelength, 254/520/620 nm. We could attain to the detection limits as 0.01~0.05 ${\mu}$g/mL (254 nm) and 0.005~0.01 ${\mu}$g/mL (520 nm) for six red tar color additives, and 0.05 ${\mu}$g/mL (254 nm) and 0.002 ${\mu}$g/mL (620 nm) for Fast green FCF. This analytical method was applicable to determine the tar color additives contained in several commercial cold syrups.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.1025-1032
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• 2005

This study was carried out to separate ovotransferrin in chicken egg white by gel chromatography and heparin affinity chromatography. In gel filtration which was performed with 50mM Phosphate buffer (pH 7.2, 0.15M salt) at a flow rate of 2.0 ml/min, ovotransferrin and ovalbumin were eluted together in fraction number 11-16. In order to separate pure ovotransferrin, fraction No. 12-14 of them which have high concentration of ovotransferrin were concentrated and rechromatographed. However, the ovotransferrin did not separated clearly. In heparin affinity chromatography, the separation was performed with 50mM ethylaminetetraacetic acid (EDTA, pH7.2) and 50mM Phosphate buffer (pH 7.2, 0.15M salt contained) on ferrous and ferric ion saturated column at as same flow rate as gel filtration system's. Ovotransferrin and albumin were eluted together at 10-15min (fraction No.3) and 15-20min (fraction No.4), respectively. However, purified ovotransferrin was eluted at 156-165min and 165-175min (tube No.32-33) with 50 mM phosphate buffer (pH 7.2, 0.15M salt free), respectively. Heparin affinity chromatography with ferric ion saturated column was resulted in the best separation of ovotransferrin rather than separation by gel chromatography and ferrous ion saturated heparin affinity chromatography.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.317-317
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• 2011

Enhanced ICRF (Ion Cyclotron Range of Frequency) ion heating of H-mode D(H) plasma will be tried in 2011 KSTAR experimental campaign. Minority heating is a main ion heating scheme in the ICRF. Its efficiency increases as the hydrogen minority ratio increases in deuterium plasmas. And it should be sustained at a lower level than the critical minority ratio. Consequently, it is important to elevate the critical ratio to maximize ion heating and it is possible by increasing the ion temperature or parallel wave number (k${\parallel}$) of the antenna. Increasing the k${\parallel}$ is not a good approach since the coupling efficiency decreases exponentially with regard to k${\parallel}$ as well. So the remaining method is to increase ion temperature by using NB (Neutral Beam). Ion heating fraction of NB increases as the electron temperature increases. Therefore, we will try to heat electron by using ECH together with NB ion heating before ICRF power injection. The ICRF heating efficiency will be compared with respect to several NB+ECH+ICRF heating combinations through several diagnostics such as XICS (Xray Imaging Crystal Spectroscopy), CES (Charge Exchange Spectroscopy) and neutron measurement. The theoretical background and the experimental results will be presented in more detail in the conference.

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.37-45
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• 1983

유제품(乳製品)의 품질(品質)과 밀접(密接)하게 관련(關聯)되어 있는 skim milk protein의 가열(加熱)에 의(依)한 상대변화(狀態變化)를 단백질(蛋白質) 화학적(化學的) 측면(側面)에서 연구(硏究)하였다. 1. Skim milk 중의 calcium농도(濃度)가 높아질수록 가열시(加熱時) 점도(粘度)는 급증(急增)하였으며 gel화(化)가 일어나는 온도(溫度)는 점점 저하(低下)되었다. 이러한 사실(事實)로 보아 calcium ion은 유단백질(乳蛋白質)의 열안정성(熱安定性)에 결정적(結定的) 영향(影響)을 미치며 calcium존재(存在) 하(下)에서 가열(加熱)시킬 때에는 우유단백질(牛乳蛋白質)들을 균일분산계(均一分散系)로부터 불균일회합상태(不均一會合狀態)로 전이(轉移)시키는 것으로 결론(結論)되었다. 2. 일정(一定) 온도(溫度) skim milk의 안정성(安定性)에 대(對)한 가열시간(加熱時間)의 효과(效果)는 전혀 나타나지 않았다. 3. 등전침전(等電沈電)시킨 casein을 재용해(再溶解)시킨 후(後), skim milk 내(內)에서와 동일(同一)한 calcium농도(濃度) 환경(環境)으로 조절(調節)하고 가열(加熱)하였을 때 skim milk가 불안정성(不安定性)을 보이는 온도(溫度)보다도 저온(低溫)에서 침전(沈澱)으로 분리(分離)되었다. 따라서 가열(加熱)에 불안정(不安定)한 구분(區分)은 whey protein일 것으로 추정(推定)하였으며, 이는 skim milk 내(內)에서 casein에 의(依)하여 보호(保護)되는 것으로 해석(解析)되었다. 5. pH를 변경(變更)시킨 skim milk의 점도(粘度) 증가(增加)에는 calcium ion에 의(依)한 기여(寄與)가 컸으며, calcium은 유단백질(乳蛋白質)의 응집(凝集)을 촉진(促進)할 때 Ca-bridge로 작용(作用)하는 것이라고 결론(結論)되었다. 6. 비가열(非加熱)의 skim milk는 6개의 fraction으로 분획(分劃)되었음에 비(比)하여, $95^{\circ}C$에서 10분(分) 가열(加熱)했을 때는 fraction A 및 B가 소실(消失)되었고 새로운 fraction F@를 출현(出現)시켰다. 7. Electrophoretogram에서 fraction C 및 C#는 모두 3개의 band를, fraction F 및 F#는 모두 4개의 band를 나타냈으며 가열(加熱) 전후(前後)의 이동도(移動度)에도 차이(差異)가 없었다. Fraction D는 6개의 band로 D#에는 그 외(外)에도 3개의 band가 더 나타났다. fraction E 및 E#는 모두 4개의 band를 보였으나, 그 성분(成分)들의 이동도(移動度)는 모두 대응(對應)되지 않았다. Fraction A 및 B, 그리고 fraction D 및 E에는 가열(加熱)로 인(因)하여 변화(變化)를 받게되는 유단백성분(乳蛋白成分)이 포함(包含)되어 있을 것으로 추정(推定)되었다.

• Journal of the Korean Vacuum Society
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• v.2 no.4
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• pp.404-409
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• 1993

Adorption of nitric oxide on the Pt(III) surface sputtered by Ar-ion has been studied using thermal desorption spectroscopy and Auger electron spectroscopy. Ar-ion sputtering creates a precursor state of ($NO\beta$ stage) adsorbe dat defect sites. The precursor state is characterized by the terminal bent species . At low coverge mos 샐 adsorbed NO dissociates . And as increasing the coverage, the fraction of dissociation remains about 80%.

• Journal of Plant Biology
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• v.33 no.4
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• pp.325-332
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• 1990

Light membrane vesicles were isolated from the zucchini hypocotyl by floatation on ficoll density gradients and the proteins were solubilized with Triton X100. Three ATP-hydrolyzing enzymes were partially purified by ion-exchange and gel filtration chromatography and isoelectric focusing. There are plasma membrane-type ATPase whose activity was inhibited by vanadate but not by nitrate, tonoplast-type ATPase which was sensitive to nitrate but insensitive to vanadate and one having a phosphatase activity with a pI value different from that of an acid phosphatase. A fraction was obtained after DEAE-ion-exchange chromatography crossreacting with polyclonal antibodies against Ca2+ -ATPase from human erythrocytes.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.5
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• pp.677-685
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• 1999

Aerosol mass size distributions were measured at Kosan, Cheju Island in April 1998 and their compositions were analyzed. Microorifice Uniform Deposit Impactor(MOUDI) was used to collect aerosols. Sulfate and ammonium ions were predominatly present at fine mode of the aerosols while nitrate, chloride, and metal ions were mostly at coarse mode. Based on the size distribution of nitrate, it is suggested that most nitrate were from gas to particle conversion on coarse particles. Non-sea salt(nss) fraction of sulfate accounted for more than 90% of total sulfate mass concentration. In general, ion concentrations in this study are lower than those measured at the same site from the previous studies. Ion balance and chloride ion levels indicates that there had been anthropogenic chloride emission sources near to the site during the measurements.