• Journal of Hydrogen and New Energy
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• v.25 no.5
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• pp.468-474
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• 2014

This study was conducted to evaluate the characteristics of mesophilic fermentative $H_2$ production from food waste which was treated by food waste disposer. It was found that $H_2$ yield and lag phase were affected by particle size of food waste. The $H_2$ yield decreased with increasing particle size while lag phase increased. The maximum $H_2$ yield was found $0.584{\pm}0.03$ mol $H_2$/mol hexose at particle size smaller than 0.30 mm. The $H_2$ production rate was also affected by chemical composition of food waste. The $H_2$ production rate linearly decreased with increasing proteins to carbohydrates ratio(P/C ratio) where the maximum value was $0.031{\pm}0.006$ mol $H_2$/mol hexose h at 0.17.

• Nuclear Engineering and Technology
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• v.39 no.1
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• pp.1-8
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• 2007

Hydrogen and electricity are expected to dominate the world energy system in the long term. The world currently consumes about 50 million metric tons of hydrogen per year, with the bulk of it being consumed by the chemical and refining industries. The demand for hydrogen is expected to increase, especially if the U.S. and other countries shift their energy usage towards a hydrogen economy, with hydrogen consumed as an energy commodity by the transportation, residential and commercial sectors. However, there is strong motivation to not use fossil fuels in the future as a feedstock for hydrogen production, because the greenhouse gas carbon dioxide is a byproduct and fossil fuel prices are expected to increase significantly. An advanced reactor technology receiving considerable international interest for both electricity and hydrogen production, is the modular helium reactor (MHR), which is a passively safe concept that has evolved from earlier high-temperature gas-cooled reactor (HTGR) designs. For hydrogen production, this concept is referred to as the H2-MHR. Two different hydrogen production technologies are being investigated for the H2-MHR; an advanced sulfur-iodine (SI) thermochemical water splitting process and high-temperature electrolysis (HTE). This paper describes pre-conceptual design descriptions and economic evaluations of full-scale, nth-of-a-kind SI-Based and HTE-Based H2-MHR plants. Hydrogen production costs for both types of plants are estimated to be approximately $2 per kilogram.

• The Journal of Pediatrics of Korean Medicine
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• v.26 no.3
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• pp.30-45
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• 2012

Objectives The suppressive effect of CSBHT has been mysterious. Thus, the present study is designed to investigate the suppressive effect and its mechanism. Methods To investigate the anti-allergy effect from ChungShimBoHyeolTang(CSBHT), RBL-2H3 cell was used and examined by Real-Time PCR, and IL-4 and IL-13 from RBL-2H3 was examined by ELIS. In addition, GATA-1, GATA-2, NFAT-1, NFAT-2, c-Fos, c-Jun, NF-${\kappa}B$ p65 transcription factors of RBL-2H3 mast cell were examined by Western Blotting. Also, OVA/alum-sensitized mice were orally administrated CSBHT and serum OVA-specific IgE production, IL-4, and IL-13 production in splenocytes supernatant were examined. Results As a result of treating with CSBHT extract, RBL-2H3 mast cells significantly suppressed the IL-4 and IL-13 mRNA expression and IL-4 and IL-13 production. Western blot analysis of transcription factors involving IL-4 and IL-13 expression also revealed a prominent decreases of mast cell's specific transcription factors including GATA-1, GATA-2, NFAT-1, NFAT-2, c-Fos, and NF-${\kappa}B$ p65. Also, examining the mice, administration of CSBHT suppressed the amount of OVA-specific IgE in OVA/alum-sensitized mice and IL-4 and IL-13 production in splenocytes supernatant. Conclusions The study suggested that the anti-allergic activities of CSBHT suppresses IL-4 and IL-13 production from the Th2 cytokines by suppressing transcription factors as GATA-1, GATA-2, NFAT-1, NFAT-2, c-Fos and NF-${\kappa}B$ p65 in mast cells.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.325-331
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• 2002

investigated to maximize the production of fibrinolytic enzyme from Fomitella fraxinea mycelia. Among the tested media, Coriolus versicolor medium (CVM) showed the highest production for the enzyme. 2% galactose, 0.6% yeast extract and 0.1% $NaNO_3$, 0.1% $K_2HPO_4$, and 0.05% $MgSO_4$.$7H_2O$ as carbon, nitrogen, phosphorus, and inorganic salt sources resulted in the maximum level of the enzyme activity, respectively. The enzyme production from F. fraxinea was reached to highest level after the cultivation for 10 days at $25^{\circ}C$ and pH 9. The enzyme activity of culture supernatant was most active at $40^{\circ}C$ and pH 10. The activity of the enzyme was inhibited by phenylmethylsulfonylfluoride and aprotinin, suggesting that it is a serine protease.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.450-459
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• 2017

This study evaluated the effects of culture conditions, including carbon and nitrogen sources, L-monosodium glutamate (MSG), and initial pH, on gamma-aminobutyric acid (GABA) production by Lactobacillus brevis HYE1 isolated from kimchi, a Korean traditional fermented food. L. brevis HYE1 was screened by the production analysis of GABA and genetic analysis of the glutamate decarboxylase gene, resulting in 14.64 mM GABA after 48 h of cultivation in MRS medium containing 1% (w/v) MSG. In order to increase GABA production by L. brevis HYE1, the effects of carbon and nitrogen sources on GABA production were preliminarily investigated via one-factor-at-a-time optimization strategy. As the results, 2% maltose and 3% tryptone were determined to produce 17.93 mM GABA in modified MRS medium with 1% (w/v) MSG. In addition, the optimal MSG concentration and initial pH were determined to be 1% and 5.0, respectively, resulting in production of 18.97 mM GABA. Thereafter, response surface methodology (RSM) was applied to determine the optimal conditions of the above four factors. The results indicate that pH was the most significant factor for GABA production. The optimal culture conditions for maximum GABA production were also determined to be 2.14% (w/v) maltose, 4.01% (w/v) tryptone, 2.38% (w/v) MSG, and an initial pH of 4.74. In these conditions, GABA production by L. brevis HYE1 was predicted to be 21.44 mM using the RSM model. The experiment was performed under these optimized conditions, resulting in GABA production of 18.76 mM. These results show that the predicted and experimental values of GABA production are in good agreement.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.331-343
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• 1998

Sublethal dose of bacterial lipopolysaccharide (LPS) would induce protection against cardiac ischemic/reperfusion (I/R) injury. This study examines the following areas: 1) the temporal induction of the cardio-protection produced by LPS; and 2) the relations between a degree of protection and the myocardial prostacyclin ($PGI_2$) production. Rats were administered LPS (2 mg/kg, i.v.), and hearts were removed 1, 4, 8, 14, 24, 48, 72,and 96 h later. Using Langendorff apparatus, haemodynamic differences during 25 min of global ischemia/30 min reperfusion were investigated. The concentration of $PGI_2$ in aliquots of the coronary effluent was determined by radioimmunoassay as its stable hydrolysis product $6-keto-PGF1_{\alpha}$ and lactate dehydrogenase release were measured as an indicative of cellular injury. LPS-induced cardiac protection against I/R injury appeared 4 h after LPS treatment and remained until 96 h after treatment. $PGI_2$ release increased 2-3 fold at the beginning of reperfusion compared to basal level except in hearts treated with LPS for 48 and 72 h. In hearts removed 48 and 72 h after LPS treatment, basal $PGI_2$ was increased. To determine the enzymatic step in relation to LPS-induced basal $PGI_2$ production, we examined prostaglandin H synthase (PGHS) protein expression, a rate limiting enzyme of prostaglandin production, by using Western blot analysis. LPS increased PGHS protein expression in hearts at 24, 48, 72, 96 h after LPS treatment. Induction of PGHS expression appeared in both isotypes of PGHS, a constitutive PGHS-1 and an inducible PGHS-2. To identify the correlationship between $PGI_2$ production and the cardioprotective effect against I/R injury, indomethacin was administered in vivo or in vitro. Indomethacin did not inhibit LPS-induced cardioprotection, which was not affected by the duration of LPS treatment. Taken together, our results suggest that $PGI_2$ might not be the major endogenous mediator of LPS-induced cardioprotection.

• Journal of Ginseng Research
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• v.32 no.3
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• pp.264-269
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• 2008

Ginsenosides are major components in Panax ginseng and known to have numerous pharmacological activities such as anti-cancer, anti-diabetes, anti-viral and anti-atherosclerosis effects. In this study, the regulatory activities of G-Rg3 and its derivative 25-hydroxy Rg3 (G-Rg3-2H) on the production of nitric oxide (NO) in macrophages and the proliferation of lymphocytes prepared from spleen and bone marrow under treatment of lipopolysaccharide (LPS) or concanavalin (Con) A were examined. G-Rg3 and G-Rg3-2H dose-dependently inhibited NO production from LPS-activated RAW264.7 cells and in agreement, these compounds protected RAW264.7 cells from LPS-mediated cytotoxicity. In contrast, G-Rg3-2H dose-dependently inhibited lymphocyte proliferation induced by both LPS and Con A, while there was no inhibition by G-Rg3. Therefore, our data suggest that these compounds may be applied for NO-mediated or lymphocyte-mediated immunological diseases.

• Microbiology and Biotechnology Letters
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• v.8 no.2
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• pp.77-85
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• 1980

This experiment was conducted to investigate the conditions for production and the characteristics of pretenses. Aspergillus oryzae KC-15, which is selected as a superior strain for the production of the protease, was used in this study. The results obtained were as follows: 1. The optimum culture time for the production of acid, neutral and alkaline protease on wheat bran medium were about 48, 48 and 72hr, respectively. The protease-produced by the strain were mainly alkaline and neutral one, but the production of acid protease was feeble extremely. 2. The addition of NaH$_2$PO$_4$, Na$_2$HPO$_4$, glucose, rice powder and Na-glutamate respectively to wheat bran media were effective for the production of alkaline and neutral protease, and the addition of (NH$_4$)$_2$HPO$_4$, glucose and rice powder respectively were effective for the production of acid protease. 3. Characteristics of professes(equation omitted) 4. As a heat resistance agent, NaH$_2$PO$_4$was the most effective one. The optimum amount of NaH$_2$PO$_4$was 10mg for alkaline and neutral protease, and 5mg for acid protease. 5. The heat resistance of the Protease by NaH$_2$PO$_4$was not recognized mostly above 6$0^{\circ}C$. 6. After the treatment of enzyme solution with 10mg of NaH$_2$PO$_4$for 30 minutes at 55$^{\circ}C$, the residual activities measured for alkaline, neutral and acid protease were 58, 57 and 55％ respectively.

• Journal of Ceramic Processing Research
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• v.21 no.1
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• pp.57-63
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• 2020

Chemical looping hydrogen production (CLHP) is an attractive technology for H₂ production due to its ability to produce H₂ and capture CO₂ from fossil fuels simultaneously. In this paper, we present MgFe₂O₄ as an oxygen carrier material with high efficiency, low cost, and stable properties for CLHP. The redox reactions occurred reversibly in the fuel, steam, and air reactor as MgFe₂O₄→MgO/Fe, MgO/Fe→MgO/Fe₃O₄, and MgO/Fe₃O₄→MgFe₂O₄, respectively. The oxygen transfer capacities of MgFe₂O₄ for 5% H₂/N₂ and 5% CO/N₂ gases were about 23 wt% at 900 ℃. Both the oxygen transfer capacity and rate were well maintained during 10 redox cycles at 900 ℃. No phase changes or agglomeration occurred as the redox cycle number increased. Similarly, MgFe₂O₄ did not exhibit significant degradation in its total amount or maximum rate of H₂ production during four redox cycles. The average calculated amount of H₂ production for MgFe₂O₄ was 2,806 L/day per unit mass (kg).

• Journal of Plant Biotechnology
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• v.48 no.4
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• pp.278-288
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• 2021

The development of bioenergy through biomass has gained importance due to the increasing rates of fossil fuel depletion. Biomass is important to increase the productivity of bioethanol, and production of biomass with high biomass productivity, low lignin content, and high cellulose content is also important in this regard. Inorganic salts are important in the cultivation of biomass crops for the production of biomass with desirable characteristics. In this study, the roles of various inorganic salts in biomass and bioethanol production were investigated using an in vitro tobacco culture system. The inorganic salts evaluated in this study showed dramatic effects on tobacco plant growth. For example, H₂PO₄ substantially improved plant growth and the root/shoot (R/S) ratio. The chemical compositions of tobacco plants grown in media after removal of various inorganic salts also showed significant differences; for example, lignin content was high after Mg²⁺ removal treatment and low after K⁺ treatment and H₂PO₄ removal treatment. On the other hand, NO₃^- and H₂PO₄ treatments yielded the highest cellulose content, while enzymatic hydrolysis yielded the highest glucose concentration ratio 24 h after NH₄⁺ removal treatment. The ethanol productivity after H₂PO₄ removal treatment was 3.95% (w/v) 24 h after fermentation and 3.75% (w/v) after 36 h. These results can be used as the basis for producing high-quality biomass for future bioethanol production.