Time filter

Source Type

Choi U.K.,Pohang Center for Evaluation of Biomaterials | Bajpai V.K.,Daegu University
Food and Chemical Toxicology | Year: 2010

This study was conducted to evaluate the effect of dark and light conditions on the quality characteristics of whole soybean meju, a Koran soybean fermentation starter, made by germinated soybeans. The sprouting rates of soybeans under dark and light conditions after 24 h were 25.6 ± 1.2% and 20.5 ± 1.5%, respectively and reaching to a level of 99.4 ± 0.4% and 98.9 ± 0.5%, respectively at 60 h. The pH, moisture contents and amino-type nitrogen contents had no significant differences under dark and light conditions, however, the contents were significantly different as compared to control. Also there was a significant difference in the color change values of whole soybean meju under dark and light conditions. The compositions of total organic acids in MNG, MGD and MGL were noted to be 942.2 ± 111.0, 1075 ± 120.2 and 1019 ± 108.1 mg%, respectively. However, no significant differences were observed in free amino acid contents of MNG, MGD and MGL. It was observed that isoflavone contents were significantly differed in MGD and MGL as compared to MNG. © 2009 Elsevier Ltd. All rights reserved.

Lee K.-H.,Pohang University of Science and Technology | Woo K.-C.,Pohang University of Science and Technology | Kim D.-Y.,Pohang University of Science and Technology | Kim T.-D.,Korea Research Institute of Bioscience and Biotechnology | And 5 more authors.
Molecular and Cellular Biology | Year: 2012

The mouse PERIOD1 (mPER1) protein, along with other clock proteins, plays a crucial role in the maintenance of circadian rhythms. mPER1 also provides an important link between the circadian system and the cell cycle system. Here we show that the circadian expression of mPER1 is regulated by rhythmic translational control ofmPer1 mRNA together with transcriptional modulation. This time-dependent translation was controlled by an internal ribosomal entry site (IRES) element in the 5' untranslated region (5'-UTR) ofmPer1 mRNA along with the trans-acting factor mouse heterogeneous nuclear ribonucleoprotein Q (mhnRNP Q). Knockdown of mhnRNP Q caused a decrease in mPER1 levels and a slight delay in mPER1 expression without changing mRNA levels. The rate of IRES-mediated translation exhibits phase-dependent characteristics through rhythmic interactions betweenmPer1 mRNA and mhnRNP Q. Here, we demonstrate 5'-UTR-mediated rhythmicmPer1 translation and provide evidence for posttranscriptional regulation of the circadian rhythmicity of core clock genes. © 2012, American Society for Microbiology.

Lee H.,Inha University | Oh E.-T.,Inha University | Choi B.-H.,Inha University | Choi B.-H.,Pohang Center for Evaluation of Biomaterials | And 5 more authors.
Scientific Reports | Year: 2015

Oxygen and glucose deprivation (OGD) due to insufficient blood circulation can decrease cancer cell survival and proliferation in solid tumors. OGD increases the intracellular [AMP]/[ATP] ratio, thereby activating the AMPK. In this study, we have investigated the involvement of NQO1 in OGD-mediated AMPK activation and cancer cell death. We found that OGD activates AMPK in an NQO1-dependent manner, suppressing the mTOR/S6K/4E-BP1 pathway, which is known to control cell survival. Thus, the depletion of NQO1 prevents AMPK-induced cancer cell death in OGD. When we blocked OGD-induced Ca 2+ /CaMKII signaling, the NQO1-induced activation of AMPK was attenuated. In addition, when we blocked the RyR signaling, the accumulation of intracellular Ca 2+ and subsequent activation of CaMKII/AMPK signaling was decreased in NQO1-expressing cells under OGD. Finally, siRNA-mediated knockdown of CD38 abrogated the OGD-induced activation of Ca 2+ /CaMKII/AMPK signaling. Taken together, we conclude that NQO1 plays a key role in the AMPK-induced cancer cell death in OGD through the CD38/cADPR/RyR/Ca 2+ /CaMKII signaling pathway.

Choi U.K.,Pohang Center for Evaluation of Biomaterials
International journal of molecular sciences | Year: 2010

This study was undertaken to optimize the conditions for the extraction of antibacterial activity of Perilla frutescens var. acuta leaf against Pseudomonas aeruginosa KCTC 2004 using the evolutionary operation-factorial (EVOP) design technique. Increased antibacterial activity was achieved at higher extraction temperatures and with a longer extraction time. Antibacterial activity was not affected by differing ethanol concentration in the extraction solvent. The maximum antibacterial activity of ethanolic extract of P. frutescens var. acuta leaf against P. aeruginosa, determined by the EVOP factorial technique, was obtained at an extraction temperature of 80 °C (R = -0.800(**)), 26 h (R = -0.731(**)) extraction time, and 50% (R = -0.075) ethanol concentration. The population of P. aeruginosa also decreased from 6.660 log CFU/mL in the initial set to 4.060 log CFU/mL in the third set. Also, scanning electron microscopy study of the ethanolic extract of P. frutescens var. acuta revealed potential detrimental effects on the morphology of P. aeruginosa.

Lim S.-I.,Korea Food Research Institute | Cho C.-W.,Korea Food Research Institute | Choi U.-K.,Pohang Center for Evaluation of Biomaterials | Kim Y.-C.,Korea Food Research Institute
Journal of Ginseng Research | Year: 2010

Ethanol and water extracts of white and fermented ginseng were prepared and their ginsenoside composition and antioxidant effects were assessed. The main ginsenosides in white ginseng were Rb1 > Re > Rg1, and those in fermented ginseng were Rb2 + Rb3 > Rd > Rg1. Ginsenosides Rd and Rg3 in fermented ginseng were enriched 11 and 58 times, respectively, over that in white ginseng through fermentation with five Bacillus spp. The greatest levels of 2-deoxyribose and superoxide anion dismutase-like activities were found in 50% ethanol extracts of fermented ginseng. Thus, these data suggest that white ginseng has the greatest free radical scavenging activity and that fermented ginseng has the highest antioxidant activity. © The Korean Society of Ginseng.

Discover hidden collaborations