• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.706-709
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• 2003

The antioxidant activities of methanol and dichloromethane/acetone extracts of twenty three seaweeds were tested by using 1,1-Diphenyl-2-picryl-hydrazyl(DPPH) at a $100{\mu}g/ml$ concentrations. The dichloromethane/acetone extracts of three seaweeds(Symphyocladia latiuscula, Gloiopoltis furcata, Sagassum thunbergii), were found to be most effective in DPPH radical scavenging activity. The DPPH radical scavenging effect of these seaweeds was Symphyocladia latiuscula(85.82%), Gloiopoltis furcata(82.83%), Sagassum thunbergii(74.05%) in order. These seaweeds were evaluated using the pyrogallol UV-VIS spectrophotometeric method to generate superoxide anion. Among them, the methanol extracts of six seaweeds were showed weak superoxide dismutase-like activities. The dichloromethane/acetone extracts obtained from Symphyocladia latiuscula was fractionated with $CH_2Cl_2$, n-hexane, 15% aq.MeOH, n-BuOH, $H_2O$. The 15% aq.MeOH soluble fraction exhibiting the strongest antioxidative activities was further purified by C18 column flash chromatography and reversed HPLC. The two active principles of Symphyocladia latiuscula were isolated and characterized as 2,3,6-tribromo-4,5-dihydroxybenzyl alcohol(1), 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether(2).

• Archives of Pharmacal Research
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• v.27 no.8
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• pp.840-844
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• 2004

A triterpene was isolated as a cytotoxic principle from the dichloromethane extract of Korean mistletoe (KM； Viscum album colora turn) by repeated silica gel chromatography and recrystalli-zation. In in vitro analysis of cytotoxic activity using various human and murine tumor cell lines, the dichloromethane extract of KM was highly cytotoxic against these cells. We isolated the most active compound, referred to VD-3, from the dichloromethane extract of KM. The VD-3 was shown to be less cytotoxic to normal cells (murine splenocytes). From the identification of the chemical structure of VD-3 by spectral data and chemical synthesis, the compound was proven to be epi-oleanolic acid. Tumor cells treated with VD-3 showed a typical pattern of apo-ptotic cell death, such as apparent morphological changes and DNA fragmentation. These results indicate that epi-oleanolic acid is an important compound responsible for antitumor activity of KM.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.406-412
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• 1998

Such extraction conditions as the kinds of solvent, extracting temperature, extracting time, ratio of material to solvent and particle size of material, were studied to maximize the extraction of oleoresin from chipi. Larger amount of soluble solids were extracted from seeds with nonpolar solvents (hexane, pentane, ether) for extraction, because the seeds contained large amount of crude fats and monoterpene(limonene) volatile compounds. Larger amount of soluble solids were extracted from peel with polar solvents(methanol, ethanol) of extraction because of large amount of water soluble colors, sugars and oxygenated terpene bolatile compounds in the peel. The application of the solvents in intermediate polarity (dichloromethane, acetone) resulted in more effective extraction of soluble solid and volatile compounds. Expecially, dichloromethane was an excellent solvent in extraction of volatile compounds. In the concern of volatile compound recovery yield, the optimum extraction conditions, such as temperature, time, mixing ratio of material to dichloromethane and mean particle size, were $25^{\circ}C$, 10min, 1:10(w/v), 355~250${\mu}{\textrm}{m}$ for chopi peels and 3$0^{\circ}C$, 10min, 1:8(w/v), 355~250${\mu}{\textrm}{m}$ for chopi seeds, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.255-259
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• 2007

The solvent extracts of Oenothera laciniata, which were extracted by using several solvents with different polarities, were prepared for utility as a natural preservative. The O. laciniata extract by 80% ethanol was sequentially fractionated with n-hexane, dichloromethane, ethylacetate, and butanol. The antibacterial activities and cell growth inhibition were investigated on each strain with the different concentrations of O. laciniata extracts. Antibacterial activities were shown in ethanol, ethylacetate, and butanol fraction of O. laciniata. However n-hexane, dichloromethane and water fraction showed weak antibacterial activity against the tested microorganisms. Among the five fractions, ethylacetate fraction showed the highest antibacterial activities against microorganisms tested, such as Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella Enteritidis and Salmonella Typhimurium. The polyphenolic compounds widely occurring in the traditional medicine plants have been reported to possess high antibacterial activity. The polyphenolic compounds from ethanol, n-hexane, dichloromethane, ethylacetate, butanol, and water fraction were 63.96 mg/g, 8.49 mg/g, 28.11 mg/g, 172.64 mg/g, 114.56 mg/g, and 34.91 mg/g, respectively. There are some relationships between antibacterial activity and polyphenol content in natural plant. The ethylacetate fraction could be suitable for the development of a food preservative.

• Toxicological Research
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• v.11 no.2
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• pp.273-277
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• 1995

Several metabolic modulators on the generation of carbon monoxide (CO)from dichloromethane (DCM) was examined in adult female rats. It has been known that DCM is converted to CO by cytochrome P-450 or to carbon dioxide $(CO_2)$ by glutathione-dependent metabolic reaction. In rats treated with DCM (3 mmol/kg, ip) only, the carboxyhemoglobin (COHb) level reached a peak of approximately 10% 2 or 3 hr following the treatment. Disulfiram (300 mg/kg, ip) or allylsulfide (200 mg/kg, po), both known as a selective inhibitior for cytochrome P-450 2E1, blocked the increase in COHb concentratlons almost completely suggesting that the metabolic conversion of DCM to CO is mediated by the activity of this specific type of isozyme. YH439 (125 or 250 mg/kg, po), a potential hepatoprotective agent, decreased the COHb elevation as well indicating that this chemical is a potent inhibitor for 2E1. In rats treated with pyrazine (200 mg/kg, ip) 18 hr prior to DCM the peak COHb concentration was decreased by approximately 3 or 4%. However, pretreatment of rats with pyrazine either 24 or 48 hr before DCM increased the peak COHb concentration significantly compared to the rats treated with DCM only. The results in the present study strongly suggest that the generation of CO from DCM depends on the 2E1 activity and that the pharmacological and/or toxicological action of YH439 or pyrazine in animals or human is associated with its effect on this isozyme.

• Ocean and Polar Research
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• v.29 no.2
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• pp.187-191
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• 2007

In this study, antioxidant activities of acetone/dichloromethane and methanol extracts of Arctic seaweeds were investigated. The antioxidant properties of both extracts of arctic seaweed were evaluated using two different peroxynitrite tests, including scavenging power on authentic peroxynitrite and inhibitory activities on peroxynitrite generation from 3-morpholinosydnonimine (SIN-1) producing superoxide anion and nitric oxide simultaneously in vitro. At concentration of $10\;{\mu}g/ml$, the acetone/dichloromethane and methanol extracts of Odonthalia dentata exhibited 54.6 and 64.2% inhibition against peroxynitrite generation from SIN-1 while they exhibited 24.3 and 23.0% scavenging activities on authentic peroxynitrite, respectively. On the other hand, the acetone/dichloromethane extract of Polysiphonia stricta exhibited 61.8% inhibition only against the induced peroxynitrite from SIN-1. Furthermore, the crude extracts of Odonthalia dentata and Polysiphonia stricta were fractionated into n-hexane, 85% aq. MeOH, n-BuOH, and $H_2O$ fractions, successively, and only 85% aq. MeOH fraction exhibited the best inhibition.

• Journal of the Korean Chemical Society
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• v.19 no.6
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• pp.414-419
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• 1975

The insoluble tungsten complexes with 8-hydroxy quinoline (oxine=Hox), aniline (A), and pyridine(Py) in several organic solvents have been synthesized. Using the different solvents with oxine, two different complexes have been synthesized in dichloromethane and dimethylformamide(DMF), respectively. Only one kind of complex has been synthesized with aniline in dichloromethane and with pyridine in acetone. The complexes may be formulated as $WCl_2(Hox)_2,\;[WO_2(Ox_2)],\;[WCl_3A_3],\;and\;[WO_2ClPy]$ by the results of elemental analysis, infrared spectral data, and thermogravimetric analysis.

• Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.127-132
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• 2007

The anti-inflammatory activities of dichloromethane, ethanol, and boiling water extracts of the brown seaweeds Undaria pinnatifida (Harvey) Suringar and Laminaria japonica Areschoug were examined. Ethanol extracts (0.4 mg/ear) of U. pinnatifida inhibited inflammatory symptoms in mouse ear edema by 95.3%, and dichloromethane extract inhibited erythema by 65.5%. Dichloromethane and ethanol extracts (4 g/kg bw) of L. japonica demonstrated potent antipyretic activity. Activities of the seaweed extracts were similar to those of the commonly used drugs indomethacin and acetyl salicylic acid. No acute toxicity was observed after p.o. administration of each extract (5 g/kg bw). These results were in agreement with the claims of the health care industry and indigenous medicine that the above seaweeds can be used as an effective remedy for inflammation-related symptoms.

• Analytical Science and Technology
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• v.8 no.4
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• pp.481-486
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• 1995

Quenching experiments by photoinduced electron transfer between a charged donor and a neutral acceptor were carried out in acetonitrile, dichloromethane and mixed solvents of acetonitrile and dichloromethane. Tris(2, 2'-bipyridine) ruthenium(II) ($[Ru(bpy)_3]^{2+}$) which has 2+ charge and dicyanobis (2, 2'-bipyridine) ruthenium(II) ($Ru(bpy)_2(CN)_2$) which has no charge were used as electron donors, and a series of tris(${\beta}$-diketonato) ruthenium (III) was used as acceptor. In dichloromethane, $[Ru(bpy)_3]^{2+}$ and its counter ions ($ClO{_4}^-$) form ion pair. In the estimate of ${\Delta}G$ of electron transfer, the electrostatic potential between counter ions and product ion pair produced by electron transfer must be taken into account. A similar effect of counter ions was found in mixed solvents of 10, 30, 50, 70 and 90% acetonitrile ratio in volume. The effect of counter ion on ${\Delta}G$ became smaller with the increase in acetonitrile ratio. The result in mixed solvents suggests that $[Ru(bpy)_3]^{2+}$ and its counter ions form ion pair even in 90% acetonitrile solution.

• Environmental Engineering Research
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• v.24 no.4
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• pp.600-607
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• 2019

Volatile organic compounds (VOCs) are released from various sources and are unsafe for human health. Porous materials are promising candidates for the adsorption of VOCs owing to their increased ratio of surface area to volume. In this study, activated carbon (AC) impregnated cellulose acetate (CA) electrospun mats were synthesized using electrospinning for the removal of VOCs from the air mixture of ACs, and CA solution was electrospun at different proportions (5%, 10%, and 15%) in a single nozzle system. The different AC amounts in the electrospun mats were distributed within the AC fibers. The adsorption capacities were measured for acetone, benzene, and dichloromethane, using quartz crystal microbalance. The results elicited an increasing adsorption capacity trend as a function of the impregnation of ACs in the electrospun mats, while their capacities increased as a function of the AC concentration. Dichloromethane resulted in a faster adsorption process than acetone and benzene owing to its smaller molecular size. VOCs were desorbed with the N₂ gas purging, while VOCs were adsorbed at higher temperatures owing to the increased vapor pressures. The adsorption analysis using Dubinin-Astakhov equation showed that dichloromethane is more strongly adsorbed on mats.