Byun M.-W.,Woosong University
Journal of the Korean Society of Food Science and Nutrition | Year: 2013
This study examined the immunomodulatory activities of apple seed extracts (ASE). The immunomodulatory effects were estimated through nitric oxide production, cytokine induction, protein expression of inducible nitric oxide synthase (iNOS), and the phosphylation of mitogen-activated protein kinases (MAPKs) and inhibitory kappa Bα (IκB-α) in the RAW 264.7 macrophage cell line. In the cytotoxicity asay, ASE (31 to 250 μg/mL) did not induce cytotoxicity; thus, the optimal concentration of ASE was confirmed to be less than 250 μg/mL. Nitric oxide (NO) and cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-6) production significantly increased in a dose-dependent manner. Similarly, the protein expression of iNOS and the phosphorylation of MAPKs and IκB-α were also increased by ASE treatment. Overall, our results suggest that extracts from apple seeds potentially have immunomodulatory activities on macrophages. © 2013 by The Korean Society of Food Science and Nutrition. All rights reserved.
Byun M.-W.,Woosong University
Journal of Medicinal Food | Year: 2012
Polyphenol-rich foods, such as fruits and vegetables, are protective against cardiovascular diseases, but the mechanisms of the beneficial effects are still unknown. The goal of this research was to clarify actions of procyanidin trimer (C1) in rat aortic endothelial cells (RAECs). Procyanidin C1 at concentrations up to 50μM was not cytotoxic to the RAECs. The addition of procyanidin C1 to RAECs exerted a time-dependent hyperpolarization measured using a membrane potential-dependent fluorescent probe, bis-(1,3- dibutylbarbituric acid) trimethine oxonol, whereas the hyperpolarization was significantly inhibited by the nonspecific K+ channel inhibitor tetraethylammonium chloride (TEA). Moreover, procyanidin C1 elevated intracellular Ca2+ influx, which was totally abolished in the presence of Ca2+-free solution with EGTA. Procyanidin C1 caused a significant increase in nitric oxide (NO) production. The effect was significantly inhibited by an NO synthase inhibitor, NG-monomethyl-l- arginine, or TEA. In conclusion, we demonstrated for the first time that procyanidin C1 plays a potent role in promoting Ca2+-mediated signals such as the hyperpolarization via multiple K+ channel activations and the NO release in RAECs, suggesting that procyanidin C1 may represent novel and effective therapy for the treatment of cardiovascular diseases. © Copyright 2012, Mary Ann Liebert, Inc.
Yoon K.-H.,Woosong University
Korean Journal of Microbiology and Biotechnology | Year: 2012
A bacterial strain was isolated from homemade Cheongkookjang as a producer of the β-galactosidase, capable of hydrolyzing lactose to liberate galactose and glucose residues. The isolate YB-1105 has been identified as Bacillus licheniformis on the basis of its 16S rDNA sequence, morphology and biochemical properties. β-Galactosidase activity was detected in both the culture supernatant and the cell extract of B. licheniformis YB-1105. The enzymes of both fractions demonstrated maximum activity for hydrolysis of para-nitrophenyl-β-D-galactopyranoside (pNP-βGal) under identical reaction conditions of pH 6.5 and 50°C. However, β-galactosidase activity from the culture filtrate was affected more than that from the cell free extract at acidic pHs and high temperatures. The hydrolyzing activity of both β-galactosidases for pNP-βGal was dramatically decreased by the addition of low concentrations of galactose, but was only marginally decreased by high concentrations of glucose or mannose.
Sung B.,Woosong University
Renewable and Sustainable Energy Reviews | Year: 2015
This study investigates the effects of public policy supports on the export performance of bioenergy technologies; it uses panel data from 18 countries from the 1992 to 2008 period. Panel unit-root and cointegration tests are applied, taking into account the results of structural-break tests for each time series and testing for the presence in the panel of cross-sectional dependence. Time-series data on public supports and exports are integrated and cointegrated. The results of dynamic ordinary least squares indicate that in the long term, public R&D expenditures have a positive effect on the exports, the contribution of bioenergy to the total energy supply has a negative effect on the exports, and GDP has a positive effect on the exports. The contribution of bioenergy to total energy supply responds to deviations in the previous period from the longterm equilibrium. Additionally, Blundell-Bond system generalized methods of moments estimations are made, to determine dynamic causality in a panel vector error correction mechanism setting. Evidence of a positive strong and short-term relationship from exports to R&D expenditures, and of a positive short-term causality from exports to the contribution of bioenergy to total energy supply, is found. A positive strong bidirectional relationship between GDP and exports is also uncovered. There is a positive strong, bidirectional, and shortterm relationship between GDP and the contribution of bioenergy to total energy supply. Finally, some policy implications based on the results of this study are offered. © 2014 Elsevier Ltd. All rights reserved.
Sung B.,Woosong University |
Song W.-Y.,Dongseo University
Energy Policy | Year: 2013
This article investigates the causal relationship between public policies and exports of renewable energy technologies using panel data from 18 countries for the period 1991-2007. A number of panel unit root and cointegration tests are applied. Time series data on public policies and exports are integrated and cointegrated. The dynamic OLS results indicate that in the long run, a 1% increase in government R&D expenditures (RAD) increases exports (EX) by 0.819%. EX and RAD variables respond to deviations from the long-run equilibrium in the previous period. Additionally, the Blundell-Bond system generalized methods of moments (GMM) is employed to conduct a panel causality test in a vector error-correction mechanism (VECM) setting. Evidence of a bidirectional and short-run, and strong causal relationship between EX and the contribution of renewable energy to the total energy supply (CRES) is uncovered. CRES has a negative effect on EX, whereas EX has a positive effect on CRES. We suggest some policy implications based on the results of this study. © 2012 Elsevier Ltd.