• Proceedings of the PSK Conference
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• 2003.10b
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• pp.241.3-242
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• 2003

A simple, specific and sensitive method for the determination of methyltestosterone (MT) in human serum has been developed by gas chromatography/mass spectrometry with the purpose of conducting pharmacokinetic and bioequivalence studies of MT. This method involves the use of liquid-liquid extraction with diethyl ether and derivatization with MSTFA, using 1 ml of serum obtained from volunteers orally taken 50 mg MT. MT showed good resolutions in this conditions and no significant interfering peaks were observed. (omitted)

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.58-64
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• 2004

For the utilization of chestnut inner bark as forest biomass, the diethyl ether solubles of hot water extract from chestnut inner bark was analyzed by HPLC. Each peak was identified by comparing with retention time of standard regents and their purity from obtained UV spectrum by RI detector. Identified 6 compounds were gallic acid, 3,5-dihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid and protocatecualdehyde as phenolic acids and aldehyde, and catechin and epicatechin as flavonoids.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.527-537
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• 1997

This study was performed to determine the effects of antimutagenicity of Porturaca oleracea L. in Korea. In Ames test, the ethanol extract of Poturaca oleracea L. inhibited mutagenic activity of N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), , 4-nitroquinoline-1-oxide(4NQO), benzo($\alpha$)pyrene (B($\alpha$)P) and 3-amino-1,4-dimethyl-5H-pyrido-(4,3-b)indole (Trp-P-1) in Salmonella typhimurium TA98 and TA100. But hot-water extract Poturaca oleracea L. only Inhibited mutagenic activity of MNNG in Salmonella typhimurium TA100, On 4NQO, the ethanol extract 100-1,600$\mu\textrm{g}$/plate of Porturaca oleracea L. showed a slight inhibitory effect of 13-48%, 4-47% in TA98 and TA100, respectively, but on MNNG, it showed higher inhibitory effect of 6-86% in TA100, And the treatment of 1,600$\mu\textrm{g}$/plate of ethanol extract of Porturacea L. had strong antimutagenicity with 74-87% inhibition against TA98 and TA100 induced by B(a)P and with 85-93% inhibition against TA98 and TA100 induced by Trp-P-1. The ethanol extract was fractionated with ether. chloroform, ethylacetate, butanol and water. Among them, most of the fraction except water fraction showed strong antimutagenicity effects against mutation induced by 4-NQO, MNNG, B(a)P and Trp-P-1. Chloroform fraction had strong antimutagenicity with 91% inhibition against TA100 induced by MNNG, diethyl etherfraction had strong antimutagenicity with 92%, 98% inhibition against TA98 and TA100 induced by 4NQO, Chloroform fraction had strong antimutagenicity with 97% inhibition against TA100 induced by B (a)P and diethyl etherfraction had strong antimutagenicity with 98% inhibition against both strain Induced by Trp-P-1, respectively.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.665-669
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• 1994

A rapid gas chromatographic (GC) profiling method was applied to dairy products (milk and cheeses) for the simultaneous analysis of volatile and nonvolatile organic acids. Cheese samples were first made into aqueous samples by dissolving in water. The aqueous samples were then extracted with organic solvents after the acidification and NaCI saturation. The organic layers (diethyl ether : hexane= 1 : 1) were extracted with $NaHCO_3$ saturated solution with subsequent solid-phase extraction of the aqueous phases using Chromosorb P column/diethyl ether followed by triethylamine treatment. The resulting triethylammonium salts of acids were directly converted into volatile tert.-butyldimethylsilyl derivatives, which were analyzed by dual-capillary column GC, and GC-mass spectrometry. From milk and four cheese samples studied, 31 organic acids including 21 fatty acids and other hydroxy and dioic acids were tentatively identified. The amounts of the fatty acids were different among the kinds of cheese and thus the simplified retention index (RI) spectra of organic acids were useful for the visual pattern recognition of each sample, when the Direct Comparision method between cheese and a blind sample were attempted, it was quickly recognized to be a gouda cheese with the 999 ppt match quality value.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.185-192
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• 1999

Four different parts of Hovenia dulcis $T_{HUNB}$; fruit, bark, vessel area, fruit coat were extracted with water and ethanol. The ethanol extracts of bark, fruit coat and fruit were fractionized into diethyl ether, chloroform and aqueous partitions. Ethanol extract of fruit coat increased the activity of cathepsin B up to 55 %, which can enhance the alcohol dehydration in the liver. The ethanol extracts was more effective than water extracts against the growth of Hep3B, MCF7. The ethanol extracts of bark (0.5mg/ml) inhibited 90% the growth of MCF7. Each extracts and fractions (0.5mg/ml) did not show considerable cytotoxicity on HEL299. In overall, most of the fractions had similar effects to ethanol extracts; however, diethyl ether and chloroform fractions had higher bioactivity than ethanol extracts, but aqueous fraction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1098-1105
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• 2004

In order to develop natural food preservatives, the ethanol and water extracts of the Saururus chinensis Baill were prepared. Antimicrobial activity was examined against 10 kinds of harmful microorganisms. The ethanol and water extracts showed the most active antimicrobial activity against B. subtilis and E. coli. The ethanol extract showed stronger antimicrobial activity than that of the water extract. However, the extracts did not show any antimicrobial activity against lactic acid bacteria and yeast. The minimum inhibitory concentrations (MIC) of ethanol extracts against B. subtilis and E. coli were 5 to 10 mg/mL, respectively. Antimicrobial activity of the ethanol extract was not destroyed at 40-12$0^{\circ}C$ and pH 3∼11. The ethanol extract was fractionated in the order of hexane, diethyl ether, ethyl acetate, and water fractions. The highest antimicrobial activity was found in the diethyl ether fraction.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.1-10
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• 2000

The purpose of this study is to establish the assessment techniques of hazardous chemicals by the development of analytical method of biological samples. In this study, we have developed an extraction method of nine pesticides used for rice paddy that resulted in high recovery from the spiked human urine by the liquid-liquid extraction with diethyl ether at pH 7.0. Calibration curve obtained from each pesticide standard using by gas chromatography/mass spectrometry/selected ion monitoring has shown good linearity and detection limits were the range of $0.4{\sim}2.0$ ng/mL in urine. As a biological monitoring, urine samples of local farmers exposed directly to nine pesticides in the field were collected and analyzed by GC/MS. Of the tested pesticides, metabolites of phenthoate assumed were identified by GC/MS analysis. No parent compound was detected.

• Journal of fish pathology
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• v.11 no.2
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• pp.129-136
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• 1998

In March 1997, a new rhabdovirus was isolated from moribund cultured Japanese flounder Paralichthys olivaceus in sea water tank and cage culture systems in Kyung-Nam and Chun-Nam province, Korea. At temperature $15^{\circ}C$ the virus replicated and induced cytopathic effects (CPE), which progressed to eventual cytolysis, in susceptible cell lines, including RTG-2 and EPC. The CHES-214 cell line was refractory. Virus particles were bullet-shaped and measured $70nm{\times}100$ to 150 nm in size. The isolate was sensitive to pH 3, to diethyl ether, and to heat ($50^{\circ}C$ 5 min, $60^{\circ}C$ 1 min). Viral replication was not inhibited by $10^{-4}$ M 5-iododeoxyuridine. Virus infectivity was reduced by anti-HRV (8401-H) rabbit serum, but can not reduced by antisera against infectious hematopoietic necrosis virus (IHNV), chum salmon reovirus (CSV), retrovirus of salmonid (RVS) and infectious pancreatic necrosis virus (IPNV). HRV virus antigen was detected by fluorescent antibody test (FAT) in the cytoplasm of infected EPC cell. Purified isolates virions were composed of: polymerase (L), glycoprotein (G), nucleoprotein (N) and 2 matrix proteins (M1 and M2). Based upon their relative mobilities, the estimated molecular weights of the proteins were: L, 160 kDa; G, 55 kDa; N, 45 kDa; M1, 26 kDa; and M2, 22 kDa.

• Journal of Life Science
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• v.16 no.4
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• pp.659-663
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• 2006

The extracts of Plocamium telfairiae using several solvents with different polarities were prepared and their growth inhibitory effects were examined on the human cancer cells. We investigated the cytotoxic effects of P. telfairiae extracts on HT-29 cells by the MTT reduction assay and examining the morphological change under the inverted microscope. Among three extracts, the methanol extract showed the strongest inhibitory effect on the growth of HT-29 cells. The methanol extract was further fractionated sequentially with n-hexane, diethyl ether, ethyl acetate, and aqueous for purifying crude methanol extract. The n-hexane layer among the fractioned layers showed remarkable inhibitory activity on the growth of HT-29 cells. Moreover n-hexane layer showed the notable growth inhibition effects with a dose-dependent manner against SW620, HeLa, and MCF-7 cells as well as HT-29 cells. These results indicated that P. telfairiae extracts may be contained bioactive materials with inhibitory effect on the growth of human cancer cells.

• Journal of Life Science
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• v.19 no.7
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• pp.963-967
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• 2009

This study evaluated the neuroprotective effect of extracts from the root bark of Morus alba (MA) against glutamate-induced cytotoxicity in neuronal cells. Glutamate-induced cytotoxicity was shown by MTT reduction assay. The neuroprotective effects of methanol, ethanol, and acetone extracts from MA against glutamate-induced cytotoxicity were measured. Among the three extracts, the methanolic extracts showed the highest protective effect, as determined by the results of an morphological assay, a lactate dehydrogenase release assay. Furthermore, the methanol extracts were fractionated sequentially with hexane, diethyl ether, ethyl acetate, and water layer according to degree of polarity. The hexane fractions exhibited a neuroprotective effect against glutamate-stressed N18-RE-105 cells. Therefore, these results suggest that extracts of MA could be a new potential candidate as a protective substance against glutamate-induced cytotoxicity.