• KSBB Journal
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• v.11 no.2
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• pp.238-245
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• 1996

Microbial desulfurization characterlstics of a bituminous coal have been determined by using Thiobacillus ferrooxidans. The effects of process variables (such as coal pulp density, particle size and addition of surfactants) on pyrite removal have been investigated in both shake and airlift-bioreactor culture experiments. In shake experiments, pyrite could be removed over 78% for pulp densifies below 20% (w/v) and removed below 40% for pulp densities over 30% (w/v) in 8 days. Pyrite removal decreased with increasing pulp densities, and it also decreased sharply with increasing particle sizes. In airlift bioreactor experiments, pyrite at 50% (w/v) pulp density could be removed about 50%. Its value is much higher than 15% at the same pulp density in a shake experiment. With addition of surfactants, pyrite removal was enhanced in shake experiments significantly, whereas it was slightly decreased in an airlift bioreactor experiment.

• Journal of Life Science
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• v.25 no.11
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• pp.1331-1337
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• 2015

S-allylcysteine (SAC) is an aged garlic derived water soluble organosulfur compound and has been suggested to have anticarcinogenic activity against diverse types of cancer cells. This review summarizes the cellular signaling pathways and molecular mechanisms whereby SAC exerts its effects on cellular proliferation, apoptosis, cell cycle progression and metastasis based on the results from both in vitro and in vivo studies. SAC activates proapoptotic proteins including Bax and caspase-3, but suppresses antiapoptotic Bcl-2 family proteins to bring about cancer cell death through mitochondria-mediated intrinsic pathway. SAC also inhibits cellular proliferation by inducing cell cycle arrest in which SAC reduces expression and activation of NF-κB, cyclins, Cdks, PCNA and c-Jun, but elevates expression of cell cycle inhibitor proteins p16 and p21 through suppression of both PI3K/Akt/mTOR and MAPK/ERK signaling pathways. And, SAC inhibits invasion and metastasis of cancer cells by inducing suppression of both angiogenesis and epithelial-mesenchymal transition (EMT) through decreased cyclooxygenase (COX)-2 expression and increased E-cadherin expression which were then caused by suppression of inhibitory transcription factors Id-1 and SLUG from SAC-mediated inactivation of both MAPK/ERK and PI3K/Akt/mTOR/NF-κB signaling pathways. Furthermore, SAC prevents toxic compound-induced carcinogenesis by inducing antioxidant enzymes such as glutathione-s-transferase (GST). Thus, SAC can be considered as a potential chemotherapeutic agent for the prevention and treatment of cancer.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.336-342
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• 1999

Various surface treatment techniques can be applied onto the surface of carbon fibers to increase interlaminar shear strength (ILSS). In a commerciaI treatment, first, surface of carbon fiber was oxidized, after that, a sizing agent was coated to improve handleability and adhesion to the matrix. Carbon fiber reinforced composites (CFRC) which is made of these fibers show excellent ILSS but show low vaIues of impact strength In this study, reactive and ductile interphase was introduced between fiber and matrix to increase both the ILSS and impact strength. By using electric conductivity of carbon fibers, flexible polymers which have ionizable group, i.e., MVEMA and EMA, were coated onto the surface (oxidized) of carbon fiber by the technique of electrodeposition. ILSS and impact strength of composites were evaluated according to the surface treatments, i.e., commercial sizing treatment, interphase introduction, and without sizing treatment. Izod impact strength and ILSS of CFRC were simultaneously improved in thc thickness range of $0.08{\sim}0.12{\mu}m$ of MVEMA interphase. Water resistance of the composites was decreased by introducing MVEMA interphase.

• Applied Biological Chemistry
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• v.49 no.4
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• pp.270-275
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• 2006

[ $2{\beta},\;3{\alpha}$ ], 23-trihydroxyrus-12-ene-28-oic acid was isolated from Trapa pseudoincisa S. et Z. It has a common structure of pentacyclic triterpenes and belongs to the amyrin ursolic acid group. The cytotoxic effect of this compound was investigated in human hepatoma cell line HepG2. $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid showed dose-dependent cytotoxicity in HepG2 cells. Confocal microscopy data showed that green fluorescence was increased in $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid treated-HepG2 cells in a time-dependent manner. $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid also increased the sub-G1 cell population of HepG2 cells as well as ladder-like DNA fragmentation. Taken together, our results indicate that $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid induced apoptosis in HepG2 cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1564-1570
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• 2009

The volatile flavor compounds of kimchi and its sub-ingredients were analyzed using GC/MS. The major volatile compounds of kimchi were identified as sulfide compounds, organic acids and alcohols. It was confirmed that the major volatile flavor compounds of kimchi originated from sub-ingredients such as garlic, ginger, onion and reek. To reduce the characteristic odor of kimchi, the sub-ingredients (garlic, ginger, onion and reek) were chopped into a length of 5 mm and a thickness of 0.3 mm, blanched at 100${^{\circ}C}$ for 2 min, and then soaked in water at 4${^{\circ}C}$ for 12 hr. The effects of soaking of the sub-ingredients on sensory evaluation with regard to characteristic odor of kimchi such as sour and moldy odor were investigated. The sour and moldy odors of kimchi were significantly reduced by the soaking of sub-ingredients. Additionally the addition of soaked sub-ingredients in kimchi had influences on the change of pH, total acidity and lactic acid bacterial count of kimchi during fermentation.

• Clean Technology
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• v.6 no.2
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• pp.121-127
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• 2000

There are several kinds of hazardous materials in incinerator flue gas, such as particulate matter, acid gas, heavy metal, dioxin, etc. The activated carbon adsorption is considered as one of the methods removing dioxin from flue gas. Without any additional equipment and facilities, the activated carbon was mixed with lime and sprayed in the semi-drying reactor of an incinerator and filtered in the bag filter, and its efficiency of removing hazardous organic material was investigated. 1,2-dichlorobenzene (o-DCB) was used as a precursor material of dioxin and the effects of the activated carbon amount, the operating temperature of the reactor, and the atomizer r.p.m were measured and analyzed. Experimental results showed that the optimum outlet temperature of the reactor was $145^{\circ}C$ considering the performance of the bag filter, and the adsorption performance improved with the increase of the atomizer r.p.m. Also the performance of removing o-DCB in the bag filter is higher than of the semi-drying reactor.

• Clean Technology
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• v.6 no.2
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• pp.113-119
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• 2000

Due to the toxicity of dioxin in the incinerator flue gas, it becomes a severe social problem. Activated carbon adsorption process is one of the methods for removing dioxin in the flue gas and was investigated its performance for removing hazardous organic compounds. Since dioxin is very hazardous material, 1,2-dichlorobenzene(o-DCB), one of the precursor material of dioxin, was used as adsorbate. The effects of air flow rate, pressure drop in the bag filter, operation temperature of bag filter, and kinds of adsorbents on the removal of o-DCB were measured and analysed. Experimental results showed that the operating temperature was recommended within the range of $140{\sim}170^{\circ}C$ considering the operating condition of incinerator. Also it was necessary to maintain the pressure drop of bag filter $120mmH_2O$ for enhancing the adsorption at the surface layer of activated carbon formed on the bag filter. The use of mixture of same amount of activated carbon and diatomite showed more than 90% removal of o-DCB and also reduced the consumption of activated carbon.

• Food Science and Preservation
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• v.24 no.6
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• pp.786-794
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• 2017

This study analyzes the chemical composition and thiobarbituric acid reactive substance levels of Godulbaegi (Youngia sonchifolia M.) depending on collection time. The moisture and crude fat content in leaf and root decreased, while crude fiber, crude protein, carbohydrate, and ash increased with increases in collection time. The mineral elements tended to increase in each sample with increases in collection time. The content of vitamin B increased as collection time increased. Vitamin C content was approximately five times higher in the leaves than that in the roots. Total amino acids in leaf and root increased considerably as collection time increased content of phenolic compounds in root were higher than that in the leaf and these contents increased. Antioxidant activity of Godulbaegi was higher in the root than in the leaf and increased as collection time increased.

• Journal of Life Science
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• v.25 no.4
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• pp.397-405
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• 2015

S-allylcysteine (SAC) is a water-soluble organosulfur compound abundant in the aged garlic extract and has been drawing attention as a diet-derived alternative agent not only for the effects of anti-oxidation and anti-inflammation but also for the prevention and treatment of various types of cancer. However, there is no report about the anticancer effects of SAC on cervical cancer cells. The aim of this study was to analyze the inhibitory effects of SAC on cell proliferation of cervical cancer cell line, HeLa and to examine its effects on the apoptosis and cell cycle as the cellular mechanisms of anti-proliferation. For this, we examined effects of different concentrations of SAC on cell proliferation according to treatment periods. Treatment with SAC not only induced morphological changes but also resulted in the reduction of cell viability and the inhibition of concentration- and time-dependant cell proliferation of HeLa. Furthermore, SAC also induced fragmentation of DNA in both DNA fragmentation and TUNEL assays, and induced cell cycle arrest at the G₂/M phase in cell cycle analysis. These results suggest that SAC inhibits proliferation of HeLa at least in part through the induction of apoptosis and the cell cycle arrest.

• Clean Technology
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• v.15 no.1
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• pp.60-66
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• 2009

Adsorptive removal of tetrahydrothiophene (THT) and tert-butylmercaptan (TBM) that were widely used sulfur odorants in pipeline natural gas was studied using various ion-exchanged NaY zeolites at ambient temperature and atmospheric pressure. In order to improve the adsorption ability, ion exchange was performed on NaY zeolites with alkali metal cations of $Li^+,\;Na^+,\;K^+$ and transition metal cations of $Cu^{2+},\;Ni^{2+},\;Co^{2+},\;Ag^+$. Among the adsorbents tested, Cu-NaY and Ag-NaY showed good adsorption capacities for THT and TBM. These good behaviors of removal of sulfur compound for Cu-NaY and Ag-NaY zeolites probably was influenced by their acidity. The adsorption capacity for THT and TBM on the best adsorbent Cu-NaY-0.5, which was ion exchanged with 0.5 M copper nitrate solution, was 1.85 and 0.78 mmol-S/g at breakthrough, respectively. It was the best sulfur capacity so far in removing organic sulfur compounds from fuel gas by adsorption on zeolites. While the desorption activation energy of TBM on the Cu-NaY-0.5 was higher than NaY zeolite, the difference of THT desorption activation energy between two zeolites was comparatively small.