• YAKHAK HOEJI
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• v.54 no.3
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• pp.200-204
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• 2010

Nuclear factor-${\kappa}B$ (NF-${\kappa}B$) plays critical roles in physiological and pathological processes such as immune function, cellular growth, homeostasis, apoptosis, and inflammation. As part of our ongoing efforts to develop novel NF-${\kappa}B$ inhibitory agents, we reported that KL-1156 (6-hydroxy-7-methoxychroman-2-carboxylic acid phenylamide) exhibited potent inhibitory activity of NF-${\kappa}B$. For further structure-activity relationship, a series of 7-aryloxy-chroman-2-carboxylamide derivatives were synthesized to explore their inhibitory activities of NF-${\kappa}B$.

• Biomolecules & Therapeutics
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• v.14 no.4
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• pp.220-225
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• 2006

Derivatives of penicillanic acid sulfones are known to be irreversible inhibitors of $\beta$-lactamase. Eight 6-tricyclic methylene penicillanic acid sulfones were prepared, and their $\beta$-lactamase inhibitory activities were evaluated against $\beta$-lactamase types I, II, III and IV. Among the tricycles attached to 6-exomethylenepenam sulfones, thiazolobenzimidazole(12a-12b), fluorene(12c), and carbazole(12e), showed inhibitory activity on type I, II and III $\beta$-lactamase. But phenanthrene(12d), and anthracene(12f-12h) derivatives showed little $\beta$-lactamase inhibitory activity. The synergic effects of the selected compound(l2b) in 1:4 combination with piperacillin showed some protection to piperacillin for the resistant strains of E. coli DC2 and P. aeruginosa 1771.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.216.1-216.1
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• 2003

P. ginseng C.A. Meyer is one of the most widely used herbal medicine in Asia. It has been used for the treatment of many disorders. Its major constituent is known to be ginsenosides, and there are many documents about bioactivities of ginsenosides such as anti-oxidant, anti-tumorigenic, anti-fatigue, and anti-inflammatory activities. Some of these activities are supposed to have some correlation with inhibitory action of cyclooxygenase (COX). Ginsenosides from P. ginseng and sapogenins were evaluated for their inhibitory effects against both cyclooxygenase-1 and -2 (COX-1 and -2). Inhibitory activity was evaluated by measuring prostaglandin E$_2$ (PGE$_2$) production from arachidonic acid with an ELISA reader. (omitted)

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.410-415
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• 2008

The nutritional characteristics and functionalities of the polyplant extracts(PPE) from the extraction of various plants were assessed for the development of a new functional food. The PPE contained 42.95 g of glucose, 22.61 g of fructose, and 12.48 g of sucrose per 100 g of PPE as free sugar, and its reducing sugar contents was measured at 480.6 mg per g of PPE. Among free amino acids, proline contents was the highest at 0.58 g per 100 g of PPE, and it contained only 12.65 mg of malic acid and 6.92 mg of tartaric acid per g of PPE as an organic acid. The antioxidant activity of PPE was the highest at 91.6%, whereas SOD-like activity and xanthin oxidase inhibitory activity, which are associated with anti-aging effects, were 21.6% and 9.3%, respectively. HMG-CoA reductase inhibitory activity was 10.0% and anti-dementia acetylcholinesterase inhibitory activity was quite low(5.1%).

• Korean Journal of Plant Resources
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• v.26 no.6
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• pp.673-677
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• 2013

In order to examine the effects of Korean cucurbitaceous plants on sonic hedgehog pathway and growth of cancer cells with over-activated hedgehog pathway, we measured the sonic hedgehog conditioned medium (shh-CM) induced alkaline phosphatase (ALP) activity and cell viability of pancreatic cancer cell lines by treatment of cucurbitaceous plants. Among the tested cucurbitaceous plants, Actinostemma lobatum Maxim, Cucumis sativus L., Momordica charantia L., Schizopepon bryoniaefolius Maxim and Trichosanthes kirilowii Max, var. japonica Kitam showed the potent inhibitory effects (> 50 % at $20{\mu}g/mL$) on shh-CM induced ALP activity. We also evaluated the cell viability of pancreatic cancer cells treated with the cucurbitaceous plants. The tested cucurbitaceous plants showed the very weak effects on cancer cell proliferation but, T. kirilowii Max, var. japonica Kitam presented the inhibitory effect of 72.7 % on the proliferation of pancreatic cancer cells at $20{\mu}g/mL$. Taken together, we screened the effects of Korean cucurbitaceous plants on shh-CM induced ALP activity and cell viability of pancreatic cancers to search for the modulators of the hedgehog pathway leading to the inhibition of cancer cell proliferation. T. kirilowii Max, var. japonica Kitam, among the tested cucurbitaceous plants, showed the inhibitory effects on the shh-CM induced ALP activity and the proliferation of pancreatic cancer cells.

• Korean Journal of Pharmacognosy
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• v.37 no.4 s.147
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• pp.307-313
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• 2006

Reactive oxygen species (ROS) and formation of advanced glycation end products (AGEs) play an important role in the pathogenesis of diabetic nephropathy by hyperglycemia. To find natural agents improving diabetic nephropathy, 63 natural resources which used to the treatment of diabetes mellitus in a folk remedy were investigated with an in vitro system employing radical scavenging activity and inhibitory activity of AGEs formation. In results, the extracts of Aspalathus linearis, Rubus coreanus, Rosa rugosa, and Epimedium koreanum significantly inhibited the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical with $IC_{50}$ values less than $10{\mu}g/ml$. The extracts of Zea mays, Cucurbita moschata, Cudrania tricuspidata, and Aspalathus linearis effectively reduced the formation of AGEs compared with the positive control $N-acetyl-_L-cystenine$ (NAC) and aminoguanidine (AG). In addition, the extracts of Aspalathus linearis, Commelina communis, Cornus officinalis, and Lespodeza cuneata showed the all inhibitory activity against DPPH radical and AGEs formation. Also, these resources definitely showed the radical scavenging activity against peroxynitrite $(ONOO^-)$ and hydroxyl radical $({\cdot}OH)$ relating to high glucose-induced ROS production. Thus, these results suggest that some natural resources may regulate the initiation and progression of diabetic nephropathy through inhibition of ROS production and AGEs formation.

• Natural Product Sciences
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• v.16 no.4
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• pp.291-294
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• 2010

In obesity, adipocytes undergo abnormal growth characterized by increased cell numbers and differentiation. Thus, inhibition of mitogenesis of preadipocytes and their differentiation to adipocytes would be beneficial for the prevention and progression of obesity. In the present study, we attempted to evaluate antiadipogenic activity of adlay (Coix seed, the seed of Coix lacryma-jobi L. var. ma-yuen Stapf) employing preadipocytes cell line, 3T3-L1 as an in vitro assay system. Because several varieties of adlay are in use in Korea, anti-adipogenic activity of three varieties of adlay such as Sang-Gang, Jo-Hyun and Yulmu-Ilho was evaluated. All the three varieties of adlay showed significant inhibitory activity on adipocyte differentiation as assessed by measuring fat accumulation using Oil Red O staining. Adlay, however, showed little effects on adipocyte proliferation. Further studies with interval treatment demonstrated that adlay exerted inhibitory activity on adipocyte differentiation via acting on early stage of adipogenesis. Taken together, adlay might be useful in the prevention of obesity.

• Natural Product Sciences
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• v.16 no.4
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• pp.239-244
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• 2010

Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signaling, has served as a potential drug target for the treatment of type 2 diabetes. The MeOH extracts of twenty-nine medicinal plants, traditionally used in Vietnam as anti-diabetes agents, were investigated for PTP1B inhibitory activity in vitro. The results indicated that, most materials showed moderate to strong inhibitory activity with $IC_{50}$ values ranging from $3.4\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$; meanwhile, eleven extracts (37.9%) could demonstrate PTP1B activity with $IC_{50}$ values less than $15.5\;{\mu}g/mL$; sixteen extracts (55.2%) could demonstrate PTP1B activity with $IC_{50}$ values ranging from $15.5\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$. The study may provide a proof, at least in a part, for the ethno-medical use in diabetes disease of these plants.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3219-3223
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• 2014

Ochnaflavone, a naturally occurring biflavonoid composed of two units of apigenin (5,7,4'-trihydroxyflavone) joined via a C-O-C linkage, was first synthesized and evaluated its inhibitory activity on $PGE_2$ production. Total synthesis was accomplished through modified Ullmann diaryl ether formation as a key step. Coupling reactions of 4'-halogenoflavones and 3'-hydroxy-5,7,4'-trimethoxyflavone were explored in diverse reaction conditions. The reaction of 4'-fluoro-5,7-dimethoxyflavone (2c) and 3'-hydroxy-5,7,4'-trimethoxyflavone (2d) in N,N-dimethylacetamide gave the coupled compound 3 in 58% yield. Synthetic ochnaflavone strongly inhibited PGE2 production ($IC_{50}=1.08{\mu}M$) from LPS-activated RAW 264.7 cells, which was due to reduced expression of COX-2. On the contrary, the inhibition mechanism of wogonin was somewhat different from that of ochnaflavone although wogonin, a natural occurring anti-inflammatory flavonoid, showed strong inhibitory activity of $PGE_2$ production ($IC_{50}=0.52{\mu}M$), and seems to be COX-2 enzyme inhibition. Our concise total synthesis of ochnaflavone enable us to provide sufficient quantities of material for advanced biological studies as well as to efficiently prepare derivatives for structure-activity relationship study.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3219-3222
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• 2011

Three types of ${\beta}$-ketoacyl acyl carrier protein synthase (KAS) are important for overcoming the bacterial resistance problem. Recently, we reported the discovery of a antimicrobial flavonoid, YKAF01 (3,6-dihydroxyflavone), which exhibits antibacterial activity against Gram-positive bacteria through inhibition of ${\beta}$-ketoacyl acyl carrier protein synthase III (KAS III). In this report, we suggested that YKAF01 can be an inhibitor ${\beta}$-ketoacyl acyl carrier protein synthase I (KAS I) with dual inhibitory activity for KAS I as well as KAS III. KAS I is related to the elongation of unsaturated fatty acids in bacterial fatty acid synthesis and can be a good therapeutic target of designing novel antibiotics. We performed docking study of Escherichia coli KAS I (ecKAS I) and YKAF01, and determined their binding model. YKAF01 binds to KAS I with high binding affinity ($2.12{\times}10^6$) and exhibited an antimicrobial activity against the multidrug-resistant E. coli with minimal inhibitory concentration (MIC) value of 512 ${\mu}g$/mL. Further optimization of this compound will be carried out to improve its antimicrobial activity and membrane permeability against bacterial cell membrane.