• Journal of the Korean Chemical Society
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• v.21 no.1
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• pp.67-72
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• 1977

Author studied on the isolation technique and properties of the products obtained by the reaction of soybean oil with maleic anhydride. Before studying above purpose, oleic acid and linoleic acid contained in soybean oil were reacted with maleic anhydride. Thin-layer chromatography using silica coated plate and solvent system consisting of petroleum ether-diethyl ether = 7:3∼5:5 (v/v) resulted in good effects on the isolation of maleic anhydride adducts. Four fractions were separated and fraction No. 2 were analyzed by IR & UV spectrophotometer, obtaining the following conclusions. In the case of oleic acid adduct and linoleic acid adduct, it were conjectured that the succinic acid type adduct was formed. In the case of conjugated $C_{18}$ fatty acid adduct, cyclohexene type adduct was formed which differed from oleic acid and linoleic acid adduct.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.493-498
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• 1998

An attempt was in this to analyzer volatile flavor components of sancho(Zanthoxylum schinfolium). Essential oils in sancho tree and fruit isolated by a simulataneous steam distillation (SDE) methods using n-pentane/diethyl ether as solvent. A total of 57 and 44 components were identified by gas chromatography(GC) and combined gas chromatography spectrometry (GC-MS), respectively. Granyl acetate(29.23%) geraniol (6.80%, p-isopropyl-2-chclohexenone(5.53%), phellandral (4.10%) in sancho fruit and 4, 6, 6-trimethyl-bicyclo(7.47%), T-carvelo(4.60%, ${\alpha}$-cypernone(3.58%) in sancho tree were found to be major volatile flavor. 22 compnents including myrcene, limonene, 1, 8-cinol in sancho fruit and 10 components including 4-(1-methylethyl)-cyclohexanol, methyl undecyl ketone in sancho tree were identified. The contents of unsaturated fatty acids of palmitic acid(24.34%), myristic acid(3,68%) in sancho tree was higher than that of the sancho fruit.

• Natural Product Sciences
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• v.15 no.3
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• pp.162-166
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• 2009

Oxczaasssaidative stress plays an important role in neuronal cell death, which is associated with neurodegenerative conditions such as Alzheimer's and Parkinson's disease. This study evaluated the neuroprotective effect of Euryale ferox (EF) extracts against glutamate-induced cytotoxicity in hybridoma N18-RE-105 cells. Specifically, neuroprotective effects of methanol and ethanol extracts were evaluated by the MTT reduction assay. The ethanol extracts of EF displayed dose dependent protection against neuronal cell death induced by 20 mM of glutamate. Furthermore, the ethanol extracts of EF was sequentially fractionated with hexane, diethyl ether, ethyl acetate, and water layer according to degree of polarity. The hexane fractions exhibited neuroprotective effect against glutamate-stressed N18-RE-105 cells. Overall, results suggest that EF extracts can potentially be used as chemotherapeutic agents against neuronal diseases.

• Environmental Analysis Health and Toxicology
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• v.15 no.1_2
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• pp.45-51
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• 2000

Analytical method of 4-nitrotoluene (4-NT) in water was developed by 9as chromatography/mass selective detector/selected ion monitoring (GC/MSD/SIM). 4-NT was extracted with diethyl ether. Organic layer was washed with 5 % sodium chloride solution. The influence of solvent and evaporation condition on extraction of 4-NT were examined. The retention time of 4-NT peak was 7.72 min. Coefficient of variation (CV) of 4-NT (ng) within day and day-to-day was ranged from 7.0 to 14.6% and from 7.7 to 20.8%, respectively. Recovery of 4-NT was ranged from 84 to 109%, and detection limit of 4-H was lese than 1 ng/㎖.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.304-309
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• 1982

The fluorescence yields of chl-a and-b complexes bound to silicon dimer, tetramer and hexamer containing pyridine group in diethyl ether solvent, were shown the transition of excited energy through silicon polymer chain, and the maximum energy quenching were appeared at 1 : 1 ratio of chl-a and pyridine group in silicon polymer but the chl-b complexes were shown the maximum energy of fluorescene emission at the same ratio.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1029-1033
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• 1999

Seven fractions were separated by silica gel chromatography from the diethyl ether souble portion of the methanolic extract of the cultured hoelen(Poria cocos Wolf). Three fractions were separated from the Fr.II and Fr.IV by rechromatography, respectively. The most active fraction, Fr.II 3 and Fr.IV 3, were separated to 2 and 4 fractions by preparative HPLC. On the result of antimicrobial test, triterpenoids fractions showed weaker effect than benzoic acid but Fr.II 3 1, Fr.II 3 2 had an excellent antimi crobial activity. Triterpenoids fraction of hoelen(Poria cocos Wolf) showed a high inhibition activity on the growth of lung cancer, ovary cancer, skin cancer, central nerve cancer and rectum cancer cell, especially the activity of Fr.II 3 1 and Fr.II 3 2 was the highest.

• Journal of Integrative Natural Science
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• v.1 no.3
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• pp.247-249
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• 2008

자성 결정체인 $Fe_3O_4$ 나노 입자를 합성하기위하여 강한 극성 용매인 2-pyrrolidone을 연전도 반응매개체로 하여 용액 내에 $FeCl_3{\cdot}6H_2O$을 용해시켜 2-pyrrolidone의 비등점까지 나노 결정체 고온 열분해 방법을 이용하여 제조되었다. 고온 열분해 후, $Fe_3O_4$ 나노 입자는 methanol/diethyl ether (1:3)에 의해서 침전되어졌다. 합성된 $Fe_3O_4$ 나노 입자는 고결정도, 고자기성을 가지고 있으며, 수용성의 자성 나노 결정체이다. 합성된 $Fe_3O_4$ 나노 입자의 크기와 결정도는 transmission electron microscope (TEM, Tecnai F20)를 이용하여 특성 분석하였으며, area electron diffraction (SAED) pattern과 HRTEM을 이용하여 나노입자의 격자 패턴 (lattice fringes)을 확인하였다.

• Journal of Applied Biological Chemistry
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• v.44 no.2
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• pp.71-76
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• 2001

Methanol extract and solvent fractions of Aster scaber Thunb. were tested to elucidate antioxidative characteristics in vitro. Methanol extract showed strong inhibition on linoleic acid autoxidation and conjugated diene production. Hexane and diethyl ether fractions showed stronger chelating effect on $10^{-4}M\;FeCl_3$ than the other fractions. Butanol fraction had the strongest capacity on $10^{-3}M\;CuSO_4$ similar to ${\alpha}$-tocopherol. Synergistic effect of butanol fraction with histidine, methionine, and lysine on linoleic acid autoxidation had been observed. Contents of total phenol, vitamin E, vitamin C, and carotenoid were evaluated. From the results, Aster scaber Thunb. could be expected to play a role as an antioxidant in vivo.

• Journal of Food Hygiene and Safety
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• v.14 no.2
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• pp.140-145
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• 1999

Analytical method for preservatives in food was developed using gas chromatography/mass spectrometry (GC/MS). Propionic acid, sorbic acid, benzoic acid, ethyl salicylate, ethyl p-hydroxy benzoate, iso-propyl p-hydroxy benzoate, n-propyl p-hydroxy benzoate, iso-butyl p-hydroxy benzoate, n-butyl p-hydroxy benzoate, p-hydroxy benzoic acid and dehydro acetic acid were extracted from cooling beverage with diethyl ether. The polar hydroxyl and carboxyl groups of food preservatives were derivatized with N-methyl-N-tert-butyldimethylisilyl-trifluoroscetamide (MTBSTFA) to form the corresponding tert-bytyldimethyl-silylated derivatives, and submitted to GC/MS analysis. The mass spectra of the derivatives were investigated for the selection of monitoring ions for multi-residue analysis of 11 preservatives by GC/MS. The macro program was also developed for the qualitative analysis of these preservatives in food.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.6
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• pp.595-606
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• 2000

In order to compare analytical conditions for measuring PAHs(polycyclic aromatic hydrocarbons) in ambient air, a series of experiment were conducted using three different types of extraction methods that include:(1) accelerated solvent extraction (ASE), (2) soxhlet, and (3) sonification methods. Efficiency and relevant analytixal parameters for each of these methods were examined on five different types of solvents that include:(1) 10% diethyl ether in n-hexane(v/v), (2) dichloromethane, (3)cyclohexane.(4) toluene, and (5) Benzene: ethanol (4:1). Comparison of extraction efficiency for various combinations between methods and solvents was made through an application of both internal and external standard calibration techniques. The extraction efficiency tests, when checked using both internal and external standards, allowed us to derive meaningful comparison among different techniques and among solvents.