• Journal of Microbiology and Biotechnology
• /
• 제20권11호
• /
• pp.1521-1523
• /
• 2010

Bioassay-guided fractionation of a methanol extract of Ganoderma lucidum gave a pure cholesterol esterase inhibitor. On the basis of spectroscopic analysis and comparison with data from the literature, the structure of this compound was identified as $5{\alpha},8{\alpha}$-epidioxyergosta-6,22-dien-$3{\bet}$-ol (compound I). This compound inhibited cholesterol esterase activity with an $IC_{50}$ value of $42{\mu}M$. Lineweaver-Burk plot analysis revealed that compound I is a noncompetitive inhibitor. The findings of this study suggest that compound I may be the active principle of the hypocholesterolemic effect of Ganoderma lucidum.

• 동의생리병리학회지
• /
• 제17권5호
• /
• pp.1235-1242
• /
• 2003

This study was performed for the investigation of vasodilatory effects of Crataegus pinnatifida Bunge and for isolation and structure determination of the constituent from the active fraction. The fruits of this herbal drug were extracted with 80% methanol, then fractioned successively with methylene chloride, ethylacetate and n-butanol. Among the fractions, ethyl acetate fraction exhibited the most effective vascular relaxation against phenylephrine-induced arterial contraction. In order to isolate the active constituent by activity-guided fractionation, this fraction was chromatographed on silica gel to yield seven subfractions. Among the subfractions, the active one showing the most potent vascular relaxation activity was further separated by prep. HPLC with reversed phase Microsorb C-18 column using 1 % acetic acid and methanol gradient solvent system to afford one pure compound, which revealed a potent vasodilatory effect. Instrumental analyses (NMR and mass spectrometry) of the isolated constituent indicated this compound to be (-)-epicatechin. The vasodilatory action mechanism of this compound should be further investigated.

• 농업과학연구
• /
• 제29권2호
• /
• pp.91-97
• /
• 2002

식물병원균 Bipolaris sorokiniana 배양 추출물로부터 이탈리안 라이그라스 및 논피의 유근신장을 억제하는 활성물질을 분리 정제하여 각종 기기분석을 통하여 화학구조를 결정하였다. 이들 화합물들은 분자식이 $C_8H_8O_3$인 benzenoid 화합물인 3-methoxybenzoic acid와 3-hydroxy benzoic acid methyl ester로 숙주식물의 유근신장을 1000ppm에서 90% 이상 저해하였다. 이들 화합물은 식물체의 잎과 줄기에서 분리되어 항균활성 및 항류마티스 활성이 있음이 보고된바 있으나 B. sorokiniana로부터 분리되어 제초활성에 관하여 보고하기는 본 논문이 처음이다.

• 미생물학회지
• /
• 제49권2호
• /
• pp.179-183
• /
• 2013

해양에서 유래된 미생물들은 지금까지 다양한 대사체들을 생산해 왔다. 해양 미생물로부터 대사체를 규명해 내고자 하는 연구의 일환으로, Aspergillus protuberus가 선택되었다. 이 균주를 대량 배양하여 배양물을 유기용매로 추출한 후, 추출물을 실리카 겔 칼럼 크로마토그라피로 분획하였다. 그 후 분획물에 분취용 HPLC 등을 실시하여 총 3종의 대사체들을 분리하였다. 분리된 대사체들의 화학적 구조는 NMR, MS, UV 등의 기기분석 방법을 이용하여 각각 deoxybrevianamide E (1), brevianamide V (2) 및 ergosterol peroxide (3)로 동정하였다. 이 A. protuburutus가 생산해 내는 대사체에 관한 연구는 본 연구에서 처음으로 이루어졌다.

• Archives of Pharmacal Research
• /
• 제26권2호
• /
• pp.138-142
• /
• 2003

From the pulp of Euphoria longana (Longan Arillus), three cerebroside molecular species have been isolated. Six known cerebrosides, soyacerebrosides I and II, 1-Ο-$\beta$-D-glucopyranosyl-(2S,3R,4E,8E)-2-(2 -lignoceroylamino)-4,8-octadecadiene-1,3-diol (long an cerebroside I) and its 8Z isomer (Iongan cerebroside II), momor-cerebroside I, and phytolacca cerebroside, were identified as major components of these cerebroside molecular species. All the cerebrosides were shown to be a mixture of geometrical isomers (8E and 8Z) of sphingosine-type or phytosphingosine-type glucocerebrosides possessing 2-hydroxy fatty acids. The structures of these cerebrosides have been determined on the basis of chemical and spectroscopic evidence.

• 대한의생명과학회지
• /
• 제27권3호
• /
• pp.154-160
• /
• 2021

Codonopsis lanceolata has numerous chemical constituents that includes polyphenols, saponins, tannins, triterpene, alkaloids, and steroids. The extract of C. lanceolata was partitioned with Haxane, CH₂Cl₂, EtOAc, n-BuOH and MeOH. The determination of structure for lancemaside G, lancemaside B, lancemaside A were based on physicochemical and HPLC chromatogram data, including NMR and HR-MS. In addition, tangshenoside I and lobetyolin were identified in the material separation process for the extract of C. lanceolata, and content analysis was performed using HPLC. The compounds were confirmed as lancemaside G, lancemaside B, lancemaside A, tangshenoside I, and lobetyolin.

• Journal of Electrical Engineering and Technology
• /
• 제10권1호
• /
• pp.102-108
• /
• 2015

This paper proposes a new fault isolation methodology for a smart protective device which plays an agent role on the smart grid distribution system with the distributed generation. It, by itself, determines accurately whether its protection zone is fault or not, identifies the fault zone and separates the fault zone through the exchange of fault information such as the current information and the voltage information with other protective devices using bi-directional communication capabilities on the smart grid distribution system. The heuristic rules are obtained from the structure and electrical characteristics determined according to the location of the fault and DG (Distributed Generation) when faults such as single-phase ground fault, phase-to-phase short fault and three-phase short fault occur on the smart grid distribution system with DG.

• Journal of Microbiology and Biotechnology
• /
• 제22권11호
• /
• pp.1478-1481
• /
• 2012

Geldanamycin (GM) and its analogs are important anticancer agents that inhibit heat shock protein (Hsp) 90, which is a major chaperone protein in cancer cells. Accordingly, based on interest in obtaining novel natural GM derivatives, the potential of Streptomyces hygroscopicus JCM4427, a GM producer, was explored for novel natural GM derivative(s), resulting in the discovery of new GM analogs as a biosynthetic shunt product and intermediates from its fermentation broth. In this study, the fermentation, isolation, structure determination, and biological activity of the compounds, two new tetracyclic thiazinogeldanamycin (1) and 19-hydroxy-4,5-dihydrogeldanamycin (3), together with the three known 4,5-dihydrothiazinogeldanamycin (2), reblastatin (4), and 17-demethoxy-reblastatin (5), are described.

• 한국해양바이오학회지
• /
• 제2권2호
• /
• pp.73-76
• /
• 2007

A large number of natural products were worldwidely discovered from maine organisms. There are many secondary metabolites produced by maine organisms which showed very strong bio-activities and distinct bio-active mechanisms. In korea, about 350 secondary metabolites including more than 280 novel compounds have been isolated and structually defined. Many researches for developing products such as cosmetics, functional food materials, anti-fouling substances are being performed using distinct activities of marine organisms. Although the research on marine natural products has been remained at its initial or developing stage of drug development, significant progress has been made for isolation, structure determination and bioassay of secondary metabolites.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
• /
• pp.370.1-370.1
• /
• 2002

Prunella vulgaris var. lilacina (Labiatae) has been used as a Korean traditional medicine for the treatment of. fever. inflammation. urinary disadvantage and cancer. We previously isolated three $\alpha$-amyrin triterpenoids from n-butanol-I extract. They are 3$\alpha$-hydroxyurs-12-ene-28-oic acid (ursolic acid). 2$\alpha$, 3$\alpha$-dihydroxyurs-12-ene-28-oic acid and 2$\alpha$. 3$\alpha$. 19$\alpha$ trihydroxyurs-12-ene-28-oic acid (euscaphic acid) exhibiting cytotoxicity and topoisomerase I inhibition. (omitted)