• Advances in Traditional Medicine
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• v.9 no.2
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• pp.192-199
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• 2009

Bioactivity-directed isolation has led to the isolation of (-)-ent-costunolide (1) as the major active compound from Hepatostolonophora paucistipula. This compound (1) was determined by spectroscopic data interpretation. This sesquiterpene lactone (1) inhibited the growth of the dermatophytic fungus Trichophyton mentagrophytes ATCC 28185, (4 mm inhibition zone at $15{\mu}g$/disc), cytotoxic activity to murine leukaemia cell lines ATCC CCL 46 P 388D1 ($IC_{50}$ 687 ng/ml, at $0.075{\mu}g$/disk), BSC monkey kidney cell lines (100% of well at $15{\mu}g$/disk) and antiviral activity to Herpes simplex virus (0.25 mg/ml, 100% of well at $7.5{\mu}g$/disk) and Polio virus (0.125 mg/ml, 100% of well at $3.75{\mu}g$/disk). These results suggest that (-)-ent-costunolide (1) has potential antimicrobial and cytotoxic agents.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.60-67
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• 2005

Nonclassical aminobenz[cd]indole antifolates 4, 5 and 6, in which the glutamic acid moiety of the classical antifolates is substituted by 2-phenylglycinamide or 3-aminobenzamide, were synthesized and their in vitro antitumor activity was evaluated. The purpose of this substitution is that the lipophilicity is enhanced due to the aromatic ring of the target compounds for the passive transport through lipid membrane of cells while the hydrogen bonding of the amide is retained in the active site of the enzyme, thymidylate synthase, where the glutamate is originally present. The target compounds were highly cytotoxic against tumor cell lines of murine and human origin with micromolar to nanomolar $IC_{50}$ values. Most effective was compound 4 ($N^6-methyl-N^6$-[4-[(${\alpha}$(S)-aminocarbonylbenzyl) aminocarbonyl]benzyl]-2,6-diaminobenz[cd]indole)with $IC_{50}$ of 2 nM against SW480, human colon adenocarcinoma cell line, which is 650-fold more potent than the reference compound 3.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.2
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• pp.2-11
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• 2000

Technologies for high-speed transistors, active devices essential to the fabrication of millimeter wave circuits have developed drastically with the design and processing techniques. The high frequency transistors, made of GaAs or InP related compound semiconductors mainly, are in the form of MODFETs and HBTs. Other than traditional III-V compound semiconductor materials, SiGe and GaN technologies are emerging as viable candidates of millimeter-wave devices. In this paper, basis and applications of millimeter-wave transistors are introduced.

• Natural Product Sciences
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• v.16 no.1
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• pp.6-9
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• 2010

In continuing our search for biologically active compounds from Korean Compositae medicinal plants, we investigated the constituents of the aerial parts of Lactuca indica L. and isolated a phenylpropanoid derivative from its MeOH extract. The chemical structure was characterized by spectroscopic methods, including 1D and 2D NMR to be di-E-caffeoyl-meso-tartaric acid (1). Compound 1 was isolated for the first time from this plant. In this paper, we suggest that the NMR assignment at C-2 of (+)-taraxafolin-B should be corrected. In the human HBV-transfected liver cell line HepG2.2.15, the compound 1 effectively reduced HBV DNA level in the release of mature HBV particles from HepG2.2.15 cultivation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1196-1199
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• 2006

Tripterygium regelii SPRAGUE is distributed in Korea and Northern China. This extract has been used as a herb medicine, especially antiparasitic, anti-inflammatory and detoxifying agent in East asia. During our research to develop new antitumor agents from natural products, Dichlorornethane (CH$_2$Cl$_2$) extract of Tripterygium regelii SPRAGUE (DTR) showed the potent apoptotic effects in A-549 lung cancer, HeLa-3 cervical cancer, SKMEL-2 melanoma cells in a dose-dependent manner. in order to purify major compounds from DTR, column chromatography was carried out gradually. Silica gel and RP-18 column chromatography for active fractions led to the isolation of a compound. The compound determined by 1 H-NMR was turned out to De Celastrol known to have antitumor activity.

• Korean Journal of Plant Tissue Culture
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• v.24 no.3
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• pp.149-152
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• 1997

To search for a compound inhibiting the petunia callus growth from Streptomyces sp., we investigated the activity in the culture broth of 400 strains. The active compound was successively purified with solvent fractionation, silica gel column chromatography from Streptomyces sp. 9602 strain, and identified as 2, 5, 7-trihydroxy-3-(5'-hydroxyhexyl)-1, 4-naphthoquinone by 1H-NMR, EI-MS, IR and UV. It inhibited the callus growth of petunia by 50% at $32\mu\textrm{g}$/mL.

• Preventive Nutrition and Food Science
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• v.5 no.2
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• pp.75-80
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• 2000

To separate ACE inhibitors from edible plants, spices, and herbs, 285 extracts of 95 sources were screened for ACE inhibitory activity. The extract of Sinapis alba L. had the most potent ACE inhibitory activity. Mustard seeds were crushed homogeneously and extracted with hexane and water successively. Lyophilized water extract was fractionated with $H_2O$:butanol(1:1). The ACE inhibitor was purified from butanol fraction by methanol precipi-tation, gel filtration, HPLC, and FPLC with Superdex peptide HQ 10/30 column. The active fraction has been purified to homogeneity, which was proven by gel filtration using FPLC system. The yield was 0.02%. The com-pound has a molecular weight of about 640. The compound competitively inhibited ACE activity and the $IC_{50}$ value was 79$\mu\textrm{g}$/ml. The purified compound showed uterus contraction activity in isolated rat uterus.

• Archives of Pharmacal Research
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• v.18 no.2
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• pp.118-120
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• 1995

The cytotoxicity-directed fractionation of MeOH extract of Terminalia chebula fruits led to the isolation of three hydrolyzed tannins and a related compound, gallic acid(1), $1,2,3,4,6-penta-O-galloy-{\beta}-_D/-glucopyranose(II)$,. chebulagic acid (III) and chebulinic acid(IV), as active principles. They were shoen to exhibit moderate cytotoxicity against cultured human tumor cell lines including A-549, SK-OV-3, Sk-MEL-2, XF-498 and HCT-15 in vitro.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.193.3-194
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• 2003

Platelets play critical roles in both hemostasis and thrombosis. It was reported that platelet aggregation is associated with an increase in superoxide production and can be inhibited by hydroxyl radical scavengers. In the course of our search for the anti-platelet, anti-coagulant and/or anti-oxidative components from plants, the MeOH extract of Crassula cv. "Himaturi" (Crassulaceae) was observed to have both anti-aggregatory and anti-coagulant effects. A novel compound, 12-O-(4'-O-methyl-galloyl)-bergenin (1), was isolated as an active component from the EtOAC soluble fraction. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.215.2-215.2
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• 2003

Tyrosinase is an important enzyme involved in the transition steps from tyrosine to melanin. Inhibition of the tyrosinase activity could block melanin formation from tyrosine and thus prevent melanin pigmentation on skin. This may contribute to the development of new whitening agent that would be useful in the prevention of pigmentation. in this study, we isolated tyrosinase inhibitory compound from BuOH fraction of Potentilla bifurca L. var. glabrata Lehm by activity guided fractionation method. Based on spectroscopic data, the active compound was identified as a quercetin 4"-O- glucopyranoside.