• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.194.4-195
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• 2003

Two phenolic flavonoids were isolated from the traditional medicine of Eastern Asia, Caesalpinia sappan L (Leguminosae). Brazilin (1) showed a significant inhibitory activity against inducible Nitric Oxide Synthase (iNOS) in lipopolysaccharides (LPS)-induced macrophage RAW 264.7 cells with an IC$\sub$50/ value of 1.68 mg/ml, which is more potent than the positive control, L-N$\^$6/-(1-iminoethyl)lysine (IC$\sub$50/ 3.49 mM). On the other hand, caesalpine J (2) was found to be inactive in the present iNOS assay system despite of their structural similarities. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.196.2-196.2
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• 2003

The Barks of Ulmus davidiana (Ulmaceae) have been used for the treatment of insecticide, anti-boil and anti-fungi in Korean traditional medicine. Four phenolic compounds were isolated from 80% Acetone extracts. The structures of these compounds were elucidated as (+)-catechin, (+)-catechin 7-O-${\beta}$-D-glucopyranoside, (+)-catechin 7-O-${\beta}$-D-xylopyranoside and procyanidin B-1. These phenolic compounds showed significant nitrogen monoxide(NO) production inhibitory activity in IFN-${\gamma}$, LPS stimulated RAW 264.7 cell and also showed significant antioxidative activity on DPPH radical. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.201.1-201.1
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• 2003

Study of Acyl-CoA:cholesterol acyltransferase (ACAT) inhibitors from medicinal plants, we found strong inhibitory activity of ACAT enzyme from rat liver microsome by the CHC1$_3$ extract of Piper longum. Bioactivity-guided fractionation led to the isolation of Guineensine (1), its structure was elucidated by spectroscopic (IR, UV, MS and NMR) means. It inhibited ACAT activity in a dose-dependent manner with IC$\sub$50/ values of 1.2 $\mu\textrm{g}$/ml on in vitro assay using rat liver microsome.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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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.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.227.1-227.1
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• 2002

Cyclooxygenase (Cox-2) is involved in tumorigenesis. hence. considered to be a molecular target for chemoprevention and chemomodulation. Selective Cox-2 inhibitors including Celecoxib and Nimesulide have been studied for their anticancer activity when given alone and in combination with radiation or cytotoxic agents. In this study, we synthesized more than 140 analogues of Celecoxib and Nimesulide. and evaluated their inhibitory effects on Cox-l and Cox-2 activity as well as cytotoxicity in order to find promising anticancer agents having selective Cox-2 inhibitory effect. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.347.3-347.3
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• 2002

Recent study indicated that terpyridine and its derivatives displayed highly active antitumor properties. In this presentation. derivatives of terpyridines having three pyridine moieties at 2',4',6'-position of central pyridine skeleton were prepared, and evaluated their cytotoxicity against several human cancer cell lines and topoisomerase I inhibitory activities. Most of the prepared compounds showed strong cytotoxicity compared to doxorubicln. In addition. several compounds displayed better cytotoxicity than that of doxorubicin. In addition, several compounds displayed better cytotoxicity than that of doxorubicin. Structure-activity relationship study was perfomed to be indicated that [2.2':6',2']terpyidine skeleton is important to show strong xytotoxicity. Significant topoxicity. Significant topoisomerase I inhibitory activity was not observed for prepared compounds.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.140-140
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• 1998

The aim of this study was to find out the effect of hypoxic condition on the regulation of cyplal gene expression. pcyplal-Luc construct was cloned and transfected into Hepa I cells. When Hepa-I cells containing pcyplal-Luc were treated by DFO (desferrioxamine) which is iron-chelating agent, the stimulatory effect of luciferase by TCDD was decreased. This inhibitory effect of desferrioxamine on the luciferase activity was dose dependent and abolished by concomitant treatment with N$\^$G/-nitro-ι-arginine. And when cobalt chloride which is known as a hypoxia inducing chemical was administrated, the stimulatory effect of luciferase by TCDD was also decreased. This inhibitory effect of cobalt chloride on the luciferase activity was dose dependent and abolished by concomitant treatment with N$\^$G/-nitro-ι-arginine. These data showed that hypoxic condition down regulates cyplal gene expression and this might be through nitric oxide action.

• 한국버섯학회지
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• 제21권1호
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• pp.8-14
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• 2023

This study aimed to verify the whitening effect of Cordyceps militaris, which is distributed in several countries worldwide, including Korea, Japan, and China, and has various medical effects. To screen the efficacy of C. militaris, the inhibitory activity of tyrosinase, which was 66% at a concentration of 1 mg/mL, was measured. Thereafter, the survival rate of melanoma cells was measured, and cell experiments were conducted at a concentration of 90% or more in which C. militaris was not toxic to cells. After measuring the inhibitory effect of TRP-1, TRP-2, tyrosinase protein, and mRNA expression, which are factors influencing melanin synthesis, C. militaris was found to decrease in all factors, with an expression level that was significantly lower compared to quercetin. This confirmed that C. militaris stimulated with LED has excellent whitening activity and can be used as a functional whitening cosmetics material.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2023년도 임시총회 및 춘계학술대회
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• pp.43-43
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• 2023

In this study, we investigated in vitro inhibitory activity of wild-simulated ginseng (WSG) against non-alcoholic fatty liver disease using HepG-2 cells. T0901317 treatment increased the lipid accumulation in HepG-2 cells, but WSG treatment inhibited T0901317-mediated lipid accumulation. In addition, WSG downregulated T0901317-mediated expression of SREBP-1c, ACC, FAS and SCD-1 protein. In addition, WSG increased the phosphorylation level of LKB1 and AMPK. Compound C treatment blocked WSG-mediated downregulation of SREBP-1c protein. In conclusion, WSG is considered to inhibit the accumulation of lipids and triglycerides in HepG-2 cells by inducing the activation of LKB1 and AMPK successively, thereby reducing the expression of FAS, ACC, and SCD-1 through suppression of SREBP-1c expression.

• Food Science and Biotechnology
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• 제16권3호
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• pp.421-425
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• 2007

The inhibitory effect of onion extract on polyphenol oxidase (PPO) and browning of peach juice was investigated. Various reducing agents such as L-ascorbic acid, L-cysteine, dithiothreitol, glutathione, and sodium pyrosulfite strongly inhibited polyphenol oxidase extracted from peach. The enzyme was also inhibited by addition of water extract of onion. Regardless of substrates used, the addition of heated onion extract exhibited stronger inhibitory effect on peach polyphenol oxidase activity than that of the fresh one. The inhibitory effect of onion extract was dependent on heating temperature and time. The onion extract inhibited the peach polyphenol oxidase non-competitively. The heating of onion extract in the presence of glucose, glycine stimulated the inhibitory effect of the onion extract, which suggests non-enzymatic browning products produced during heating might be responsible for the stronger inhibitory action of the heated onion extract. The retardation of peach juice browning by onion extract seems to be caused by inhibition of peach PPO.