• YAKHAK HOEJI
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• v.30 no.5
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• pp.238-244
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• 1986

As one of the starting materials, methylthioacetyl chloride(7) was synthesized in fair yield from mercaptoacetic acid via methyl methylthioacetate(5) prepared by alkylation employing N, N'-dicyclohexyl-O-methylisourea(4). Then 1-$\beta$-D-arabinofuranosylcytosine-5'-methylthioacetate (3) was prepared by esterification of ara-C with obtained methylthioacetyl chloride and tested for inhibitory activity on DNA synthesis in the growing primary hepatocytes and hepatoma strains($H_4$-II-E and HTC cells). In these in vitro cell lines, the inhibitory effect of ara-C-MTA(3) on DNA synthesis was similar to that of its parent ara-C but slightly lower.

• Korean Journal of Pharmacognosy
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• v.45 no.4
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• pp.354-358
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• 2014

Aldose reductase (AR) has been demonstrated to play important role in the development of the diabetic complications such as diabetic retinopathy, diabetic neuropathy and diabetic nephropathy. To discover novel treatments for diabetic complications from natural sources, 69 Korean herbal medicines have been investigated for inhibitory activities on AR. Among them, 7 herbal medicines, Eleutherococcus sessiliflorus (stems), Artemisia japonica (whole plants), Wisteria floribunda (leaves), Eurya japonica (stems, twigs and leaves, leaves), Ampelopsis brevipedunculata (stems) exhibited a significant inhibitory activity compared with 3,3-tetramethyleneglutaric acid as positive control.

• Journal of Life Science
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• v.5 no.3
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• pp.121-125
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• 1995

To determine whether the omega 3 family, linolenic acis(LnA) is effective to inhibit carcinogens/mutagens-induced mutagenesis, we employed the Ames test using Salmonella typhimurium strain of TA100 and the SOS chromotest using Escherichia coli PQ37 strain. The inhibitory effect of LnA shown in the Ames assaying system was 95%, 78% and 73% when the mutagenicities were mediated by AFB$_{1}$, MNNG and 4-NQO, respectively. LnA shows a strong antimutagenic activity against indirect mutagen of AFB$_{1}$, whereas the same concentration of LnA exhibited weaker inhibitory effects on the direct mutagen of MNNG and 4-NQO than that of AFB$_{1}$. However. LnA reduced more than 80% of SOS responses induced by MNNG and 4-NQO when the adding concentration increased to 5%. We conclude that LnA contains in vitro antimutagenic properties and that this finding warrants further investigation both in vitro and in vivo to assess its possible chemotherapeutic potential.

• BMB Reports
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• v.38 no.6
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• pp.646-649
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• 2005

Human neuronal growth inhibitory factor (GIF), a metalloprotein classified as metallothionein-3, is specifically expressed in mammal central nervous system (CNS). In these Studies the specific antibody to human GIF was prepared and used to search the epitope of human GIF by enzyme-linked immunosorbent assay (ELISA) and sequence comparison. The result of ELISA showed the epitope of human GIF may locate on a octapeptide (EAAEAEAE) in the $\alpha$-domain of human GIF, and the result of nerve cell culture indicated that the biological activity of GIF may be affected by the specific antibody.

• Journal of Applied Biological Chemistry
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• v.48 no.2
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• pp.84-88
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• 2005

To develop functional food and anti-obesity drug through inhibition of dietary lipid absorption, inhibitory effects of herb extracts on pancreatic lipase were investigated. Due to high yield and simplicity of isolation, lipase inhibitor (ELI) was isolated from ethyl acetate extract of Eugenia aromaticum, which showed highest inhibitory activity, and characterized for development of novel functional material. Stability of ELI at high temperature and low pH was investigated. Results showed ELI is relatively stable under thermal and acidic conditions, reversible, and noncompetitive inhibitor of pancreatic lipase.

• Ocean and Polar Research
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• v.25 no.1
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• pp.129-132
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• 2003

The crude extracts of marine algae were screened for tyrosinase-inhibitory and radical scavenging effects. Among the samples tested, Symphyocladia latiuscula and Gloiopeltis furcata were found to be the most effective in DPPH radical scavenging test while Gigatina tenella, Sargassum thunbergii, and Sargassum sp. were moderately active. For the inhibition against mushroom tyrosinase, Symphyocladia latiuscula and Sargassum confusum showed the strongest inhibition. Codium adhaerens, Corallina pilulifera, Carpopeltis cornea, Halymenia acuminata, Hizikia fuziformis, Porphyra suborbiculata, and Enteromorpha linza exhibited mild inhibitory potency.

• Archives of Pharmacal Research
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• v.27 no.8
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• pp.825-828
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• 2004

Two triterpenoids (1,4) and two triterpenoid glycosides (2,3) were isolated from the root of Acanthopanax koreanum (Araliaceae). Their structures were identified as impressic acid (1), acankoreoside A (2), 3-epi-betulinic acid 28-O-［(${\alpha}-L-rhamnopyranosyl(1{\rightarrow}4)-{\beta}-D-glucopyrano-syl(1{\rightarrow}6)]-{\beta}-D-glucopyranosyl]$ ester (3), and ursolic acid (4) by physicochemical and spectro-scopic methods. Of these compounds, impressic acid (1) exhibited a potent inhibitory activity against NFAT transcription factor ($IC_{50}:{\;}12.65{\;}{\mu\textrm{m}}$).

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.23-23
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• 1998

To understand structural and functional basis of loaded energy in the metastable native structure of inhibitory serpins (serine protease inhibitors), we characterized mutations that decreased the loaded energy of ${\alpha}$$_1$-antitrypsin and simultaneously influenced its inhibitory activity. Various folding defects such as side-chain locking, buried polar groups in unfavorable hydrophobic environment, and cavities were found as the structural basis of the metastability of ${\alpha}$$_1$-antitrypsin in a region presumably directly involved in the formation of complex between the inhibitor and a target protease.(omitted)

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.1-6
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• 2017

In relation to the global increase trend of obesity population, there is a demand for the development of foods having high functional activity by mass-extracting anti-obesity active substances using mulberry product such as leaf and fruit. Therefore, we evaluated the antiobesity efficacy according to varieties by using the mulberry leaves and fruit extracts. At the same time, high active varieties were selected. For this purpose, the effects of the extracts of the mulberry leaf and fruit on 3T3-L1 adipocyte differentiation were examined. As a result, in the case of mulberry leaves, the lipid accumulation inhibitory rate of 'Cheongolppong' was higher than that of the control at $500{\mu}g/ml$ treatment. And in the case of the extract of mulberry fruit, 'Daesim' showed the highest lipid accumulation inhibitory rate compared with the control at 50 times of diluted extract.

• Korean Journal of Pharmacognosy
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• v.26 no.1
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• pp.62-65
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• 1995

Dopamine ${\beta}-hydroxylase$ (DBH) catalyses the enzymatic reaction of dopamine to norepinephrine. For the purpose of isolating DBH inhibitors from natural resources, thirty one kinds of medicinal plants were screened by tracing the inhibitory activities against bovine adrenal DBH, utilizing tyramine as a substrate. Among the crude drugs tested, leaves of Lactuca sativa L., Gardeniae Fructus, Magnoliae Flos and Scutellariae Radix showed potent enzyme inhibitory activities against DBH.