• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.236-241
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• 2004

In Escherichia coli, L-lysine biosynthetic pathway is composed of nine enzymatic reactions. It has been well established that most of the lysine biosynthetic genes are regulated by the lysine availability, even though they are all scattered around the chromosome without forming any multigenic operon structure. However, no transcriptional regulatory mechanism has been identified except for the activation of lysA gene by the LysR. In this study, changes in transcriptome profiles of wild type cells and lysR deletion mutant cells grown in the absence or presence of lysine were investigated by using DNA microarray technique. Microarray data analysis revealed three groups of genes whose expression varies depending on the availability of lysine or LysR or both. To further examine the regulatory patterns of lysine biosynthetic genes, lacZ operon fusions were constructed and their expression was measured under various conditions. Obtained results strongly suggest that there is an additional regulatory mechanism which senses the lysine availability and coordinates gene expression.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.583-589
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• 2002

The rheological properties of apple pectins and tomato pectins with different degrees of side branches (sample I and sample II) were investigated with wide range of shear rate by theological modeling. Among the Power law model, Cross model and Carreau model, the Carreau model was the best fitted to the experimental data. Increasing in branching of apple pectins resulted in higher zero-shear viscosity $({\eta}_0)$. But, tomato pectins that have a low degree of side branches were shown litte difference between sample I and sample II. It is concluded that side branches of pectins can result in significant difference in rheological properties. And, this is predicted by the Carreau model.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1937-1943
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• 2020

Although classical metabolic engineering strategies have succeeded in developing microbial strains capable of producing desired bioproducts, metabolic imbalance resulting from extensive genetic manipulation often leads to decreased productivity. Thus, abiotic strategies for improving microbial production performance can be an alternative to overcome drawbacks arising from intensive metabolic engineering. Herein, we report a promising abiotic method for enhancing lycopene production by UV-C irradiation using a radiation-resistant ΔcrtLm/crtB+dxs+ Deinococcus radiodurans R1 strain. First, the onset of UV irradiation was determined through analysis of the expression of 11 genes mainly involved in the carotenoid biosynthetic pathway in the ΔcrtLm/crtB+dxs+ D. radiodurans R1 strain. Second, the effects of different UV wavelengths (UV-A, UV-B, and UV-C) on lycopene production were investigated. UV-C irradiation induced the highest production, resulting in a 69.9% increase in lycopene content [64.2 ± 3.2 mg/g dry cell weight (DCW)]. Extended UV-C irradiation further enhanced lycopene content up to 73.9 ± 2.3 mg/g DCW, a 95.5% increase compared to production without UV-C irradiation (37.8 ± 0.7 mg/g DCW).

• Journal of the Korean Wood Science and Technology
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• v.50 no.4
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• pp.256-271
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• 2022

Activated carbon (AC) derived from coconut shells (CS-AC) was obtained through pyrolysis at 700℃ and subsequently activated with H₃PO₄. AC was ground in a Wiley mill several times to form powder particles at particle scales of 80, 100, and 200 meshes. The characterization of the AC was studied using scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FT-IR), and surface area analysis (S_BET). The CS-AC-200 mesh resulted in a higher percentage of mesopores and surface area. This particle size had a larger surface area with angular, irregular, and crushed shapes in the SEM view. The smaller particles had smoother surfaces, less wear, and increased curing depth and ratio of the hardness of the resin composite. Based on the characterization results of the AC, it is evident that CS-AC with a 200 mesh particle size has the potential to be used as a filler in biocomposites.

• Journal of the Korean Society of Food Culture
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• v.25 no.6
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• pp.801-809
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• 2010

This study investigated the quality characteristics of Sulgidduk with different levels (0, 4, 8, 12, 16%) of added yam powder by measuring water content, color value, texture, and sensory quality. The water content of Sulgidduk decreased significantly (p<0.05) by increasing the amount of yam powder. The Hunter's L value of Sulgidduk decreased, and the a and b values increased significantly. Mechanical texture parameters, such as hardness, cohesiveness, gumminess, adhesiveness, and chewiness decreased significantly (p<0.05) as the amount of added yam powder increased. The springiness of the 0, 4, 8 and 12% yam Sulgidduk was not different significantly, but springiness decreased significantly in the 16% yam Sulgidduk. Hardness increased significantly during storage, whereas cohesiveness, gumminess, and adhesiveness decreased. Springiness of the control sample increased significantly, but the Sulgidduk with added yam powder had the highest springiness levels during the first and second days. Chewiness was highest during the first day in all Sulgidduk preparations. The 12% yam Sulgidduk was the best in color, flavor, taste, moistness, chewiness, and overall acceptability from the sensory evaluation. These results indicate that Sulgidduk with 12% added yam powder had the best quality in sensory and texture analyses.

• Nutrition Research and Practice
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• v.18 no.2
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• pp.180-193
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• 2024

BACKGROUND/OBJECTIVES: Obesity is a major cause of metabolic disorders; to prevent obesity, research is ongoing to develop natural and safe ingredients with few adverse effects. In this study, we determined the anti-obesity effects of Rosa multiflora root extract (KWFD-H01) in 3T3-L1 adipocytes and Sprague-Dawley (SD) rats. MATERIALS/METHODS: The anti-obesity effects of KWFD-H01in 3T3-L1 adipocytes and SD rats were examined using various assays, including Oil Red O staining, gene expression analyses, protein expression analyses, and blood biochemical analyses. RESULTS: KWFD-H01 reduced intracellular lipid accumulation and inhibited the mRNA expression of peroxisome proliferator-activated receptor γ (PPARγ), cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding proteins (C/EBPα), sterol regulatory element-binding transcription factor 1 (SREBP-1c), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS) in 3T3-L1 cells. KWFD-H01 also reduced body weight, weight gain, and the levels of triglycerides, total and LDL-cholesterol, glucose, and leptin, while increasing high-density lipoprotein-cholesterol and adiponectin in SD rats. PPARγ, C/EBPα, SREBP-1c, ACC, and FAS protein expression was inhibited in the epididymal fat of SD rats. CONCLUSION: Overall, these results confirm the anti-obesity effects of KWFD-H01 in 3T3-L1 adipocytes and SD rats, indicating their potential as baseline data for developing functional health foods or pharmaceuticals to control obesity.

• Journal of the Korean Wood Science and Technology
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• v.52 no.4
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• pp.393-403
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• 2024

As an archipelagic country, Indonesia is surrounded by large and small islands. Many mangrove plant species are found along the coasts surrounding large and small islands. Besides their conservation value, mangrove plants provide various benefits, including the use of their leaves, fruit, bark, and wood as raw materials in pharmaceutical and other industries. Additionally, mangrove wood is a potential raw material for pulp and paper production. It is essential to study the fiber dimensions of the wood to identify the appropriate characteristics of raw material for pulp and paper. Therefore, in this study, we comprehensively analyzed the differences in the wood fiber dimensions of seven mangrove species from the Indramayu Regency, West Java Province, namely Avicennia alba, Bruguiera gymnorhiza, Bruguiera cylindrica, Hibiscus tiliaceus, Sonneratia ovata, Sonneratia caseolaris, and Excoecaria agallocha. For this analysis, maceration followed the Forest Product Laboratory guidelines, and preparation followed the Sass method. The fiber length, diameter, and lumen diameter were measured using a light microscope. Based on the values of the length and dimension derivatives, the fibers of these mangrove wood species were grouped into quality classes II or III for use as raw materials for the pulp and paper industry. The wood fibers of H. tiliaceus, A. alba, S. caseolaris, and E. agallocha met the quality class criterion II, whereas wood species fibers of B. gymnorhiza, B. cylindrica, and S. ovata met the quality class criterion III.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.5
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• pp.425-431
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• 2005

The systems-level analysis of microbes with myriad of heterologous data generated by omics technologies has been applied to improve our understanding of cellular function and physiology and consequently to enhance production of various bioproducts. At the heart of this revolution resides in silico genome-scale metabolic model, In order to fully exploit the power of genome-scale model, a systematic approach employing user-friendly software is required. Metabolic flux analysis of genome-scale metabolic network is becoming widely employed to quantify the flux distribution and validate model-driven hypotheses. Here we describe the development of an upgraded MetaFluxNet which allows (1) construction of metabolic models connected to metabolic databases, (2) calculation of fluxes by metabolic flux analysis, (3) comparative flux analysis with flux-profile visualization, (4) the use of metabolic flux analysis markup language to enable models to be exchanged efficiently, and (5) the exporting of data from constraints-based flux analysis into various formats. MetaFluxNet also allows cellular physiology to be predicted and strategies for strain improvement to be developed from genome-based information on flux distributions. This integrated software environment promises to enhance our understanding on metabolic network at a whole organism level and to establish novel strategies for improving the properties of organisms for various biotechnological applications.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.288-292
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• 2004

To evaluate the quality of the crude drugs using three kinds of Cinnamomum Cortex (CC), Vietnamese CC (VCC, the stem bark of Cinnamomum obtusifolium), periderm-peeled Chinese CC (PPCC, periderm-peeled stem bark of C. cassia), Chinese CC (CCC, stem bark of C. cassia) and a Cinnamomi Ramulus (CR, the twig of C. cassia), the four essential oils were prepared by steam distillation method. Cinnamaldehdye (CAN) and an unknown substance tentatively named hydroxy-cinnamaldehdye(HCNA) were detected in the four essential oils by gas chromatography-mass spectrometry, the contents of which are significantly different one another. Vietnamese CC had the highest content of HCNA whereas CR had the highest CAN content and the lowest HCNA. Vietnamese CC exhibited the greatest cytotoxic activity against the cancer cell lines, A549, HepG-2, HL-60, P-388, U-937, and KB and CR the lowest cytotoxicity. Contents of CAN and HCNA in CCC and PPCC are positioned between VCC and CR. These results suggest that measurement of HCNA and cytotoxicity may determine the quality of CC and CR.

• Korean Journal of Medicinal Crop Science
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• v.18 no.4
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• pp.231-237
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• 2010

The present study was conducted to investigate the anti-allergic reaction with Glycyrrhiza uralensis. We examined cell viability, $\beta$-hexosaminidase release, IL-4 and IL-13 mRNA expression from RBL-2H3 cell after pre-treatment with 0, 100, 250, 500, 1000${\mu}g/m{\ell}$ of Glycyrrhiza uralensis water extracts. Effects of Glycyrrhiza uralensis on the degranulation and pro-inflammatory cytokines (IL-4 and IL-13) expression were evaluated with $\beta$-hexosaminidase assay, and RT-PCR analysis. We observed that Glycyrrhiza uralensis concentrations from 100${\mu}g/m{\ell}$ to 1000${\mu}g/m{\ell}$ had no effect on cell survival. The release of $\beta$-hexosaminidase decreased significantly with all concentrations of Glycyrrhiza uralensis extracts. The expression of the IL-4 and IL-13 mRNA were decreased by Glycyrrhiza uralensis in dose-dependent manner. These results that Glycyrrhiza uralensis has an anti-histamin effects and controls IL-4, IL-13 secretion on allergic reaction.