Kim S.-H.,Hannam University |
Ko Y.-M.,Hannam University |
Shin C.-H.,KTandG Central Research Institute |
Kim S.-J.,Hannam University
Journal of the Korean Chemical Society | Year: 2016
The theoretical investigation has been performed to predict detonation velocity, detonation pressure, and thermodynamic stability of HMX/LLM-116 cocrystal. All possible geometries of HMX, LLM-116, and cocrystal have been optimized at the B3LYP/cc-pVTZ level of theory. The binding energy for the trigger bond and cluster has been calculated to predict the thermodynamic stability. The MP2 binding energies were obtained using single point energy calculation at the B3LYP optimized geometries, and the density has been calculated from monte carlo integration. The detonation velocity and detonation pressure have been calculated using Kamlet-Jacobs equation, while enthalpy has been predicted at the CBS-Q level of theory.
Chen Q.C.,Chungnam National University |
Chen Q.C.,Xiamen University |
Zhang W.Y.,Chungnam National University |
Jin W.,Chungnam National University |
And 6 more authors.
Planta Medica | Year: 2010
Glucose uptake assay-guided fractionations on the methanol extract of Sophorae Flos led to the isolation of the flavonoids rutin (1), narcissin (2), quercetin (3), tamarixetin (4), and kaempferol (5) and the isoflavonoids cajanin (6), genistein (7), orobol (8), and pratensein (9). Among them, 1, 4, 5, 6, 8, and 9 significantly improved basal glucose uptake in HepG2 cells. Their improving effects were concentration dependent. Compounds 4, 5, 6, and 9 exhibited effects stronger than that of rosiglitazone, which has been used as an antidiabetic drug. However, 2, 3, and 7 did not show any improving effects. Stimulating glucose uptake into peripheral cells may be responsible for reducing the level of blood glucose in the circulation. Therefore, these findings demonstrate a potential to develop these flavonoids and isoflavonoids as hypoglycemic drugs. © Georg Thieme Verlag KG Stuttgart, New York.
Lee I.-S.,Chungnam National University |
Kim H.-J.,Chungnam National University |
Youn U.-J.,Chungnam National University |
Chen Q.-G.,Chungnam National University |
And 8 more authors.
Helvetica Chimica Acta | Year: 2010
Two new norlignans, cedralins A (1) and B (2), were isolated from the leaves of Cedrela sinensis. Their structures were established by extensive spectroscopic studies and chemical evidence. The absolute configurations of these compounds were determined by comparing their CD spectra with those of known compounds. In addition, their in vitro cytotoxic activity against two human-cancer cell lines was evaluated. © 2010 Verlag Helvetica Chimica Acta AG.
Jeon Y.H.,Seoul National University |
Jeon Y.H.,KTandG Central Research Institute |
Kim S.G.,Seoul National University |
Hwang I.,Seoul National University |
Kim Y.H.,Seoul National University
Journal of Applied Microbiology | Year: 2010
Aims: To examine the relationships between population growth and biological characters of the plant-growth-promoting rhizobacterium Paenibacillus polymyxa GBR-1. Methods and Results: Population growth, colony formation, starch-hydrolytic activity, and ginseng root rot caused by P. polymyxa GBR-1 isolated from a rotten ginseng root were examined in vitro and in vivo at high [1 × 108 colony-forming units (CFU) ml-1] and low (1 × 106 CFU ml-1) initial inoculum densities. Paenibacillus polymyxa GBR-1 showed strong starch-hydrolytic activity on modified starch agar with relatively low starch content, but only at certain incubation temperatures (18 and 23°C); the high-density inoculum produced bacterial colonies about nine times thicker than those formed from the lower inoculum density. Light, scanning electron, and transmission electron microscopy showed that the thick colonies from the high-density inoculum were filled with extracellular polymeric substances (EPS), in which a relatively small number of ovoid-rod-shaped bacterial cells (mostly endospore-bearing cells) were distributed. In contrast, the thin colonies from the low-density inoculum were composed of massive vegetative cells with a rectangular rod shape and minimum EPS. Fluorescent in situ hybridization (FISH) revealed that the β-amylase gene was expressed only in bacterial cells from the thick colonies formed from the high-density inoculum, but not in those from the low-density inoculum. The culture filtrate from the thick colonies produced a hydrolytic clear zone on modified starch agar, degraded starch granules in various manners, and produced rot symptoms on ginseng root tissues. Conclusions: The biological properties of colony formation, starch hydrolysis, and ginseng tissue rotting by P. polymyxa GBR-1 are interrelated; they are influenced by the initial bacterial population density but not by the in situ and the final population densities. Significance and Impact of the Study: Knowledge of disease-inducing characters of P. polymyxa GBR-1 can be used in the development of biocontrol strategies. © 2010 The Society for Applied Microbiology.
Lim Y.,Chungbuk National University |
Kwon J.-S.,Chungbuk National University |
Kim D.-W.,Chungbuk National University |
Lee S.-H.,KTandG Central Research Institute |
And 6 more authors.
Atherosclerosis | Year: 2010
Aims: Obovatol is isolated from Magnolia obovata leaves and this active component has various pharmacological properties such as anti-oxidant, anti-platelet, anti-fungal and anti-inflammatory activities. In the present study, we investigated the inhibitory effects of obovatol on in vitro vascular smooth muscle cell (VSMC) proliferation and in vivo neointimal formation in a rat carotid artery injury model. Methods and results: Obovatol (1-5μM) exerted concentration-dependent inhibition on platelet-derived growth factor (PDGF)-BB-induced rat VSMC proliferation, without exhibiting any cellular toxicity or apoptosis, as determined by cell count, [3H]thymidine incorporation and Annexin-V-binding analyses. Treatment with obovatol blocked the cell cycle in G1 phase by down-regulating the expression of cyclins and CDKs, and selectively up-regulating the expression of p21Cip1, a well-known CDK inhibitor. Effects of perivascular delivery of obovatol were assessed 14 days after injury. The angiographic mean luminal diameters of the obovatol-treated groups (100μg and 1mg: 0.78±0.06 and 0.77±0.07AU, respectively) were significantly larger than that of the control group (0.58±0.07AU). The obovatol-treated groups (100μg and 1mg: 0.14±0.04 and 0.09±0.03mm2, respectively) showed significant reduction in neointimal formation versus the control group (0.17±0.02mm2). Immunohistochemical staining demonstrated strong expression of p21Cip1 in the neointima of the obovatol-treated groups. Conclusions: These data suggest that obovatol inhibits VSMC proliferation by perturbing cell cycle progression, possibly due to activation of p21Cip1 pathway. These results also show that obovatol may have potential as an anti-proliferative agent for the treatment of restenosis and atherosclerosis. © 2009 Elsevier Ireland Ltd.
Choi S.Y.,Korea Food Research Institute |
Kim Y.O.,South Korean National Institute of Crop Science |
Son D.,KTandG Central Research Institute |
Lee J.,Kyung Hee University |
And 4 more authors.
Brain Research | Year: 2012
Resveratrol, an ingredient in grapes, has been reported to exhibit anti-cancer activity, anti-inflammatory activity, and cardiovascular protection property. Interestingly, resveratrol has been recently reported to have neuroprotective effect. This study reports the neuroprotective effect of a resveratrol derivative, 3-[2-(3,5-dimethoxyphenyl)vinyl]furan (DPVF). This synthetic DPVF conferred more protection than resveratrol against neuronal cell damage induced by oxygen and glucose deprivation in a rat hippocampal slice culture. In addition, DPVF inhibited ATP depletion following oxygen and glucose deprivation in the adult hippocampal slice. Moreover, we found that DPVF is neuroprotective against ischemic damage in rats. DPVF showed potent neuroprotection on a 4-velssel-occusion model and inhibited iron-induced malondialdehyde (MDA) formation in the rat brain tissue. These results demonstrate that DPVF might be a useful agent in reducing ischemic neuronal damage. © 2012 Elsevier B.V. All rights reserved.
Lee C.-W.,Pusan National University |
Lee H.-S.,KTandG Central Research Institute |
Cha Y.-J.,Changwon National University |
Joo W.-H.,Changwon National University |
And 2 more authors.
Preventive Nutrition and Food Science | Year: 2013
The acute and subacute hypoglycemic and antihyperglycemic effects of drinkable ripe onion juice (Commercial product name is "Black Onion Extract") were investigated in normal and streptozotocin-induced diabetic rats. For tests of acute and subacute hypoglycemic effects, ripe onion juice (5 and 15 mL/kg b.w.) was administered by oral gavage to normal Sprague Dawley rats and measurements of fasting glucose levels and oral glucose tolerance tests were performed. Tolbutamide was used as a reference drug at a single oral dose of 250 mg/kg b.w. To test anti-hyperglycemic activity, the ripe onion juice was administered to streptozotocin-induced diabetic rats by oral gavage at single dose of 15 mL/kg b.w. per day for 7 consecutive days. Oral administration of the ripe onion juice at either dosed level of 5 or 15 mL/kg b.w. showed no remarkable acute hypoglycemic effect in normal rats. The two dosed levels caused a relatively small reduction, only 18% and 12% (5 and 15 mL/kg b.w., respectively) decrease in glucose levels at 2 h after glucose loading in normal rats. However, at 3 h after glucose loading, blood glucose levels in the ripe onion juice-dosed rats were decreased to the corresponding blood glucose level in tolbutamide-dosed rats. Although showing weak hypoglycemic potential compared to that of tolbutamide, oral administration of ripe onion juice (15 mL/kg b.w.) for a short period (8 days) resulted in a slight reduction in the blood glucose levels that had elevated in Streptozotocin-induced diabetic rats. In conclusion, these results suggest that the commercial product "Black Onion Extract" may possess antihyperglycemic potential in diabetes. Copyright © 2013 by The Korean Society of Food Science and Nutrition. All rights Reserved.