• 전자통신동향분석
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• 제14권6호통권60호
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• pp.150-161
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• 1999

본 고에서는 국제표준화 기관인 ITU-T에서 진행하고 있는 B-ISDN의 일반적인 망 측면을 다루고 있는 Study Group 13의 표준화 활동에 대하여 주요 기술현황을 설명한다.

• 약학회지
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• 제41권1호
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• pp.7-13
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• 1997

A regiospecific total synthesis on the precursor(18b) of rhodomycinones is described. The anion of 3-carbomethoxy-1(3H)-isobenzofuranone(13) was respectively condensed wi th naphthalenone (12) and butenoate(8) derivatives which were, prepared by two different synthetic routes to afford 9-ethyl-6,7-dihydroxy 7,8,9,10-tetrahydronaphthacene-5,12 dione(18b) after oxidation and reduction.

• KSBB Journal
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• 제8권1호
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• pp.75-82
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• 1993

The inhibitory effect of cacao bean husk (CBH) extract on glucosyltransferase(GTasc) from Streptococcus mutans B13 was investigated. Water solube extract from CBH showeda sarong inhibitory effect (88-89%) on GTase from Streptococcus mutans Bl3. GTase inhibitors from sequential extraction by hot water or water-methanol had the strongest inhibition. Sources, fermentation, and types of solvents and fumigation processes did not influence the effect. These active compounds proved to be polyphones through acid hydrolytic analysis of the precipitates by ammonium sulfate or ethanol and proteinase K. It was also confirmed by additional column chromatography of Sephadex G-50, Sephadex LH-20 and DEAE-Sephdex A-50.

• Bulletin of the Korean Chemical Society
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• 제17권4호
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• pp.314-321
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• 1996

Isoxazolidine derivatives 7 and 8 were synthesized from N-benzyl-C-(2-benzyloxyethyl)nitrones by 1,3-dipolar cycloaddition with ethyl crotonate. The isoxazolidine derivatives were converted to β-amino acid esters 9a and 9b by reduction with zinc in acetic acid. The β-amino acid esters were reacted with methylmagnesium bromide to give the 2-azetidinones (13a, 13b). The benzyl group of 2-azetidinones were removed by Birch reduction. The products were oxidized with PDC to give 3-[1-(t-butyldimethylsilyloxy)ethyl]-4-carboxymethyl-2-azetidinone derivatives (2a, 2c).

• Journal of Species Research
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• 제13권2호
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• pp.131-135
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• 2024

Two unrecorded species, Brachynervus beijingensis and B. confusus are described from South Korea for the first time. A taxonomic study of the South Korean Brachynervus was initiated by Uchida (1955). Until now only one species, B. tsunekii, has been recorded from South Korea. In the study, we provide the diagnoses and photos of two unrecorded species of Brachynervus.

• Bulletin of the Korean Chemical Society
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• 제16권10호
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• pp.994-997
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• 1995

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5371-5376
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• 2015

Berberine (B1), isolated from stems of Coscinium fenestratum (Goetgh.) Colebr, was used as a principle structure to synthesize three phenolic derivatives: berberrubine (B2) with a single phenolic group, berberrubine chloride (B3) as a chloride counter ion derivative, and 2,3,9,10-tetra-hydroxyberberine chloride (B4) with four phenolic groups, to investigate their direct and indirect antioxidant activities. For DPPH assay, compounds B4, B3, and B2 showed good direct antioxidant activity ($IC_{50}$ values=$10.7{\pm}1.76$, $55.2{\pm}2.24$, and $87.4{\pm}6.65{\mu}M$, respectively) whereas the $IC_{50}$ value of berberine was higher than $500{\mu}M$. Moreover, compound B4 exhibited a better DPPH scavenging activity than BHT as a standard antioxidant ($IC_{50}=72.7{\pm}7.22{\mu}M$) due to the ortho position of hydroxyl groups and its capacity to undergo intramolecular hydrogen bonding. For cytotoxicity assay against human fibrosarcoma cells (HT1080) using MTT reagent, the sequence of $IC_{50}$ value at 7-day treatment stated that B1 < B4 < B2 ($0.44{\pm}0.03$, $2.88{\pm}0.23$, and $6.05{\pm}0.64{\mu}M$, respectively). Berberine derivatives, B2 and B4, showed approximately the same level of CAT expression and significant up-regulation of SOD expression in a dose-dependent manner compared to berberine treatment for 7-day exposure using reverse transcription-polymerase chain reaction (RT-PCR) assays. Our findings show a better direct-antioxidant activity of the derivatives containing phenolic groups than berberine in a cell-free system. For cell-based system, berberine was able to exert better cytotoxic activity than its derivatives. Berberine derivatives containing a single and four phenolic groups showed improved up-regulation of SOD gene expression. Cytotoxic action might not be the main effect of berberine derivatives. Other pharmacological targets of these derivatives should be further investigated to confirm the medical benefit of phenolic groups introduced into the berberine molecule.

• 한국식품과학회지
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• 제51권3호
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• pp.295-299
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• 2019

본 연구에서는 형태학적으로 판별이 어려운 옥돔과 옥두어의 종 특이 primer를 개발, 검증한 후 모니터링을 통해 위변조 된 옥돔의 유통을 예방하고자 하였다. 옥돔과 옥두어 염기서열은 clustal omega 프로그램을 이용하여 정리하였고, primer3 프로그램을 이용하여 primer를 설계하였다. Multiplex PCR 결과는 옥돔과 옥두어에 대한 종 특이적 증폭이 확인되었고, PCR 반응을 확인하기 위한 공통 유전자에 대한 증폭이 확인되었다. 옥돔을 288 bp, 옥두어를 159 bp, 공통 유전자를 502 bp로 증폭되어 각각 PCR product 사이에 100 bp 이상 차이가 나타나 정확하게 판별이 가능하였다. Multiplex PCR 민감도 실험결과 옥돔 primer가 1 ng, 옥두어 primer가 1 ng, 공통 유전자 primer가 1 ng까지 밴드가 확인되었다. 모니터링 실험결과, 옥돔 38건, 옥두어 13건으로 판정되어 시료의 어종과 실험결과가 100% 일치함을 확인하였고, 위변조 사례는 나타나지 않았다. 본 실험에서 개발된 multiplex PCR 방법은 특이도와 민감도가 확보되었고 모니터링을 통해 유통, 판매되고 있는 옥돔과 옥두어의 판별에 적합함을 확인하였다.

• Journal of Dairy Science and Biotechnology
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• 제13권1호
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• pp.13-26.4
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• 1995

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 춘계학술연구발표회(한국결정학회)
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• pp.13-13
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• 2002