• YAKHAK HOEJI
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• v.40 no.2
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• pp.177-182
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• 1996

The contents of aloesin in aloe preparations were determined by HPLC. Aloesin was extracted 3 times with ethanol for 30 minutes. The ethanol extract was concentrated and suspend ed in saturated NaCl aqueous solution and successively partitioned with dichloromethane, n-butanol. Prepared samples were analyzed by HPLC on a reverse column(Inertsil ODS-2). In assay, internal standard was a puerarin and regression of calibration curve was 0.998. Recoveries of aloesin added to aloe preparation were 98~123(%).

• Food Science and Biotechnology
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• v.16 no.5
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• pp.854-857
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• 2007

In this study, the crude methanol extract of mulberry leaves was fractionated with chloroform, ethyl acetate, n-butanol, and water, successively. The antioxidant activities of the fractions were examined with the 2-deoxyribose oxidation and linoleic acid peroxidation methods. The ethyl acetate fraction showed the strongest antioxidant activity. From it we isolated chlorogenic acid, caffeic acid, quercetin $3-O-{\beta}-D-glucopyranoside$, and kaempferol $3-O-{\beta}-D-glucopyranoside$ with preparatory octadecyl silane-high performance liquid chromatography (ODS-HPLC), and identified the compounds by nuclear magnetic resonance (NMR) and fast atom bombardment mass (FAB-MS) analyses. Overall, quercetin $3-O-{\beta}-D-glucopyranoside$ showed the strongest antioxidant activity by both the 2-deoxyribose oxidation and rat liver microsome peroxidation methods.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.11a
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• pp.10-10
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• 2000

Mechanical alloying (MA) is a powder metallurgy processing technique involving cold welding, fracturing, and rewelding of powder particles in a high-energy ball mill. This has now become an established commercial technique in producing oxide dispersion strengthened (ODS) nickel- and iron-based materials. The technique of MA is also capable of synthesizing non-equilibrium phases such as supersaturated solid solutions, metastable crystalline and quasicrystalline intermetallic phases, nanostructures, and amorphous alloys. In this respect, the capabilities of MA are similar to those of another important non-equilibrium processing technique, viz, rapid quenching of metallic melts. however, the science of MA is being investigated only during the past ten years or so. The technique of mechanochemistry, on the other hand, has had a long history and the materials produced this way have found a number of technological applications, e.g., in areas such as hydrogen storage materials, heaters, gas absorber, fertilizers. catalysts, cosmetics, and waste management. The present talk will concentrate on the basic mechanisms of formation of non-equilibrium phases by the technique of MA and these aspects will be compared with those of rapid quenching of metallic melts. Additionally, the variety of technological applications of mechanically alloyed products will be highlighted.

• Journal of Pharmaceutical Investigation
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• v.23 no.3
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• pp.133-137
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• 1993

A high-performance liquid chromatographic assay using ion-pair reverse-phase system was developed for the separation of acebutolol and acebutolol acetyl metabolite in plasma. A ion-pair reversephase system consisting of an ODS-bonded silica column and a mixture of 20% $CH_3CN$, 0.1% $H_3PO_4$, 0.035 M heptanesulfonic acid and 0.005 M tetrabutylammonium hydrogen sulfate as the mobile phase were used. Triamterene was employed as an internal standard. Based on 0.2 ml of plasma, the detection limits were 10.4 ng/ml for acebutolol and 10.3 ng/ml of acebutolol acetyl metabolite at the signal-to-noise ratio of 3:1.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.339-343
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• 1999

Pasteurella haemolytica is well known to cause severe pneumonia, consolidation and oedema of the lung, and fibrinous pleurisy under the stress and infection of virus in the cattle. In the course of our screening for antimicrobial agents against P.haemloytica, compound 51086 has been isolated from the fermentation broth of Streptimyces sp. 51086. The compound 51086 was purified by SiO2, Sephadex LH-20 and ODS column chromatographies and HPLC, subsequently. The structure of compound 51086 was determined as hygromycin A by combination of 1H NMR, 13C NMR, HMBC, and ESI-MS. This compound showed significant antibacterial activity against P.haemolytica and P.multocida.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.835-838
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• 2007

RFID는 물류와 유통분야에서 활용이 되고 있으며 RFID 시장에서 미개척 분야인 모바일 RFID 시장을 선점하기 위하여 정부주도로 모바일 RFID 시범서비스를 2006년부터 시행하고 있다. 모바일 RFID 시범서비스는 모바일 RFID 코드 해석을 위하여 Broker를 활용하는 모델을 사용하였다. 하지만 기존의 Broker 모델에는 RFID 태그 정보 조회를 위한 빈번한 ODS 질의, 그에 따른 통신 트래픽 문제, 서비스 속도 문제가 있었다. 본 논문은 Broker 모델의 성능을 개선하기 위하여 단말 어플리케이션에 RFID 코드를 필터링하는 기능을 구현하였고 단말 어플리케이션과 Broker간의 데이터 처리 과정을 단순화하여 성능을 개선하였다. 또한 모바일 RFID 서비스의 활성화를 위하여 사용자 생성 정보 시스템을 제안하고 구축하였다.

• YAKHAK HOEJI
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• v.44 no.6
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• pp.521-527
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• 2000

The root of Heracleum moellendorffii was extracted with methanol and extract was fractionated with n-hexane, $CHCI_3$ and n-BuOH. Repaeated column chromatography of silica gel, sephadex LH 20 and ODS led to the isolation of ten compounds from n-hexane fraction and n-BuOH fraction. On the basis of spectroscopic evidences, the structures of isolated compounds were identified as isobergapten, psoralen, angelicin, sphondin, xanthotoxin, skimmin, cichoriin, $heratomol-6-O-{\beta}-D-glucopyranoside$, scopolin and apterin.

• Korean Journal of Medicinal Crop Science
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• v.10 no.4
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• pp.284-287
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• 2002

Four olefinic catechols, commonly referred to as urushiol were isolated from the sap of Korean Rhus verniciflua Stokes and had the stronger inhibitory effects on the reverse transcriptase of AIDS. The hexane extract with a inhibitory effects on reverse transcriptase was purified by silica and ODS gel column chromatography. The active compounds were identified by MS and $^1H-NMR$ as 3-[8' (Z), 11' (Z), 14' -pentadecatrienyl]catechol, 3-[8' (Z), 11' (Z)-pentadecadienyl]catechol, 3-[8' (Z)-penta- decenyl]catechol, and 3-pentadecylcatechol. All of these compounds showed strong inhibitory effects on reverse transcriptase of AIDS, in which 3-pentadecylcatechol exhibited the highest activity $(IC_{50}\;:\;10.87\;{\mu}g/ml)$.

• Korean Journal of Pharmacognosy
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• v.34 no.4 s.135
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• pp.269-273
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• 2003

The leaves of Acanthopanax sessiliflorus Seem. (Araliaceae), which is native plant to Korea, have not been studied yet on triterpene constituents. Three 3,4-seco-lupane triterpenoids (Compound I-III) were isolated from the MeOH extract of this plant using Diaion HP-20P, silica gel and ODS column chromatographes. Based on physicochemical and spectroscopic data, the chemical structures of these compounds were identified as follows ; chiisanogenin (Compound I), chiisanoside (Compound II), $22{\alpha}-hydroxychiisanoside$ (Compound III).

• Korean Journal of Plant Resources
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• v.10 no.3
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• pp.227-230
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• 1997

The authors isolated four olefinic catechols, commonly referred to as urushiol, from the sap of Korean lacquer tree(Rhus vernicifera STOKES) with stronger antioxidative activities than $\alpha-tocopherol$. The hexane extract with a free radical scavenging activity was purified by silica and ODS gel column chromatography. The active compounds were identified by MS and $^1H-NMR$ as 3-[8'(Z),11'(Z),14'-pentadecatrienyl]catechol, 3-[8'(Z),11'(Z)-pentadecadienyl]catechol, 3-[8'(Z)-pentadecenyl] catechol, and 3-pentadecylcatechol. All of these compounds showed strong free radical scavenging activities on 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical, in which 3-pentadecylacatechol exhibited the highest activity ($IC_{50}$: $1.2{\mu}g/ml$). They also showed a significant inhibitory activity on lipid peroxidation ($IC_{50}$: 2.1 - 3.5 ${\mu}g/ml$). The antioxidative activity of 3-pentadecylcatechol on DPPH radical and lipid peroxidation is approximately two times greater than that of $\alpha$-tocopherol. The results suggest that the urushiol derivatices may contribute to the preservative characteristics effective against oxidative stress and could be a good source for industrial applications including a coating material.