• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.121-127
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• 1985

In studying the structural work on ciguatoxin, parrot fish collected were identified as Scarus sordidus, S. frenatus, S. scaber and S. pectarlis, in which only S. sordidus contained toxic materials. Crude toxins obtained by silicic acid column chromatography, could be separated on a DEAE-cellulose column into two fractions, ST-1(less polar) and ST-2(polar) eluted with chloroform and chloroform-methanol(1:1). Furthermore ST-1 could be changed into ST-2 by repeated chromatography on DEAE-cellulose. Rf values of ST-1 and ST-2 were 0.60-0.75 and 0.30-0.54 on TLC coated with silica gel 60F-254 developed by chloroform-methanol-water-acetic acid (90:9.5:0.2:0.3) mixture. The peaks of ST-1 and ST-2 were not observed on each HPLC chromatogram at low sensitivity(2X), but by bioassay they were detected in the fraction of 24-27ml(less polar toxin, 120ng) and 22-27 ml (polar toxin, 150 ng). Less polar ciguatoxin from morey eel viscera also showed its peak in the same elution volume(25ml). Being subjected to chromatography on basic aluminum oxide (activity grade I) or to alkaline treatment, followed by basic aluminum oxide (activity grade I) chromatography ST-1 toxin was remarkably converted into the polar toxic component supposed to be polar ciguatoxin in both cases. In the latter case, approximately 74% of the residual toxicity was changed into the polar component, accompanied by about 50% loss of the initial toxicity. More than 26% of ST-2 toxicity was transformed into the less polar toxic component supposed to be less polar ciguatoxin on a deactivated aluminum oxide (activity grade V) column.

• Advances in Traditional Medicine
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• v.9 no.4
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• pp.335-338
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• 2009

Aerial parts of Sida rhombifolia Linn. (Malvaceae) were extracted successively using various solvents and screened for various parameters of antiarthritic activity such as adjuvant-induced arthritis, motor performance, and histopathological study. The ethanol and the aqueous extracts showed potent activity; further these extracts were fractionated by using column chromatography. The fraction ET1 isolated from ethanol extract showed the most potent antiarthritic activity.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.119-126
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• 1991

The lipid fractions, lipid classes and free fatty acids in total lipids from cheese and soybeans were analyzed by column, thin-layer and gas chromatographies. The percentages of neutral lipid, glycolipid and phospholipid in cheese were 96.2, 1.1 and 0.7, whereas those in soybeans were 87.5, 0.5 and 4.3. Major lipid classes of total lipid, and neutral lipid were triglyceride, fatty acid, cholesterol, diglyceride, monoglyceride and polar lipid, and those of glycolipid and phospholipid were triglyceride, diglyceride, monoglyceride and polar lipid in total lipid from cheese. Large amounts of triglyceride and polar lipid and small amounts of diglyceride, monoglyceride and polar lipid were detected in all lipid fractions from soybeans. The higher proportion of C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C16:0, C16:1, C18:0, C18:1 and C18:2 fatty acids were found in total lipid from cheese, whereas those of C18:0, C18:2 and C18:3 fatty acids were found in total lipid from soybeans. Most predominant fatty acids are C16:0 for the total lipid of cheese and C18:2 for the total lipid of soybeans. The lower proportions of C14:1, C15:0, C17:0 and C20:0 fatty acids in total lipid from cheese and C4:0, C6:0, C10:0 and C18:0 in total lipid from soybeans were detected.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.120-127
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• 2000

Deep-fat frying is a common cooking practice. There has been considerable concern regarding the mutagenic and carcinogenic potential of thermally oxidized oils. Studies on deep-fried foods so far have revealed not much on the mutagenicity of the oils in the foods. Therefore, in the present study, it was attempted to investigate the mutagenicity ofthe thermally oxidized safflower oil. Oil was heated in a home-fryer at a temperature of 180$\pm$3$^{\circ}C$ for 48 hours. Oil samples were taken at 0, 8, 16, 24, 32, 40 and 48 hours of heating, respectively. Each sample was used to study the changes in peroxide value (POV), acid value (AV), iodine value (IV), conjugated dienoic acid (CDA) content, %, and fatty acid composition. Another series of samples were fractionated into non-polar and polar fractions by column chromatography. The mutagenicity of the samples taken from the thermally oxidized oils, as well as the non-polar and polar fractions of the thermally oxidized oils, was investigated with the Ames test. The Ames test was carried out with and without metabolic activation. Bacterial tester strains used in the present study were the histidine auxotrophic strains of Salmonella typhimurium TA100, TA1535 and TA102 were used for the detection of base pair mutations, and TA98 and TA1537 for frame shift mutations. Each series of samples was dissolved in tetraphydrofuran (inhibitor-free) and tested at doses ranging from 0.05 to 5 mg/plate. None of the oil samples taken during the 48 hour oxidation period showed any mugagenic activity. This was the case, even after the activaton with 59 mix. Also, none of the polar and non-polar fractions showed any mutagenic activity on all the strains tested.

• Archives of Pharmacal Research
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• v.17 no.6
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• pp.458-461
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• 1994

A new high-performance liquid chromatographic method with column switching has been onto a Bondapak phenyl/corsil $(37-50{\;}{\mu}m)$ precolumn and polar plasma components were washed with 0.06 M borate burffer. After valve switching, the concentrated drug were eluted in the back-flush mode and separated on a ${\mu}-Bondapak$ C18 column with acetonitrilke-phosphate buffer as the mobile phae. The method showed excellent precision, accuracy and speed with detection limit of $0.01{\;}{\mug}/ml^{-1}$. Total analysis time per smaple was less than 20 min and the coefficients of variation for intra and inter-assay were less than 5.635. This method has been successfully applied to plasma smaples from eats after oral administration of omeprazole.

• Journal of the korean society of oceanography
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• v.35 no.1
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• pp.34-45
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• 2000

Spatial distributions of phytoplankton biomass and nutrients were examined to investigate the magnitude of phytoplankton blooms along the marginal ice zone (MIZ) in the northwestern Weddell Sea during austral summer of 1995. High phytoplankton biomass was associated with the MIZ in the study area. Vertical stability induced by meltwater appears to be the most important factor controlling phytoplankton biomass distribution. Nitrate concentrations are significantly depleted within the upper water column at the phytoplankton biomass maximum. The time required to attain the observed nutrient depletion was calculated from phytoplankton biomass and nitrate depletion, which ranges from 27 to 68 days in transect 4 and from 33 to 145 days in transect 3. Phytoplankton production was also calculated from nitrate depletion and time-scales of nitrate depletion, which varies from 272 to 1752 mg C m$^{-2}$ day$^{-1}$ in transect 4 and from 327 to 2648 mg C m$^{-2}$ day$^{-1}$ in transect 3. In the Southern Ocean where primary productivity shows large temporal and spatial variations, the productivity measurement from nutrient depletion can provide an average rate of primary production during phytoplankton bloom.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.473-478
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• 1991

After the glycolipid(GL) and phospolipid (PL) of flint corn during a growth process were fractionated by silicic acid column chromatography (SACC), the GL and PL of polar lipids were separated by thin layer chromatography (TLC)and quantitative by TLC scanner and the fatty acid composition in polar lipids were determined by gas chromatography (GC). Of the GL in polar lipids were separated by TLC, monoglycosyl diacylglycerol (8.3~29.2%) was the major component, and monoglycosyl ceramide, monoglycosyl sterol were also found as minor components. Of the PL, phosphatidyl choline (27.2~29.5%) and phosphatidyl inositol (42.9~79.1%) were the major components, and phosphatidyl ethanolamine and cardiolipin were also persont in the PL. The major fatty acids in the GL were oleic(27.1~37.1%), linoleic (13.2~35.7%) and palmitic (22.5~25.6%) acids. The major fatty acids in the PL were palmitic (46.5~52.3%), heptadecanoic (23.0~25.1%) and oleic(7.2~14.6%) and GL contained a higher percentage of unsa-turated fatty acids, but PL presented that of the saturated fatty acids.

• Ocean and Polar Research
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• v.32 no.3
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• pp.321-329
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• 2010

Photosynthetic pigments, nutrients, and hydrographic variables were examined in order to elucidate the spatio-temporal variation of water column structure and its effect on phytoplankton community structure in the western channel of the Korea Strait in fall 2006 and spring 2007. High phytoplankton biomass in the spring was associated with high salinity, implying that nutrients were not supplied by coastal waters or the Yangtze-River Diluted water (YRDW) with low salinity. Expansion of the Korea Strait Bottom Cold Water (KSBCW) and a cold eddy observed during the spring season might enhance the nutrient supply from the subsurface layer to the euphotic zone. Chemotaxonomic examination showed that diatoms accounted for 60-70% of total biomass, followed by dinoflagellates. Nutrient supply by physical phenomena such as the expansion of the KSBCW and the occurrence of a cold eddy appears to be the controlling factors of phytoplankton community composition in the Korea Strait. Further study is needed to elucidate the mechanisms by which the KSBCW is expanded, and its role in phytoplankton dynamics.

• Ocean and Polar Research
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• v.26 no.2
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• pp.113-120
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• 2004

The abundance, biomass and distribution of phytoplankton, bacterioplankton and heterotrophic protists in the Bering Sea were investigated from July to August 1999. Chlorophyll a concentrations in the surface waters ranged from 0.16 to $3.79{\mu}g\;l^{-1}$ Nano-phytoplankton were found to constitute from 63 to 98% of the total phytoplankton biomass, and were clearly the dominant primary producers. The biomass of bacterioplankton in the surface layers varied from 1.46 to $20.2{\mu}g\;C\;l^{-1}$ and accounted for 30% of the total phytoplankton biomass. The biomass of bacterioplankton integrated over a depth of 0 to 100m averaged 65.4% of the total phytoplankton biomass. The surface biomass of heterotrophic protists ranged from 1.2 to $27.4{\mu}g\;C\;l^{-1}$, and was within the same order of magnitude as that of bacterioplankton. Of the total biomass of heterotrophic protists in the upper 100m of the water column, 65% was attributed to protists in the nano-size class. The results of this study suggest that bacteria and nano-protists are important components of the planktonic community in the Bering Sea during the summer season. The abundance of bacterioplankton and planktonic protists decreased from the western to northeastern and eastern regions of the Bering Sea. The abundance of these organisms also decreased with depth. The available evidence suggests that variation in the abundance and distribution of these organisms may be affected by water currents and vertical temperature variation in the Bering Sea.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.80-86
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• 2002

Volatile compounds in three different kinds of crude vinegars obtained from oak (Quercus serrata), bamboo (phyllostachys) and pine (Pinus densiflora) species were analyzed by the solid-phase microextraction (SPME) method. A total of 264 peaks were detected on the chromatograms obtained from the polar (CBP 20) and the nonpolar (CBP 1) columns, which were used for analyzing the volatile compounds in these vinegars. The major volatile compounds identified by using the polar column were 2-butanone, acetic acid, guaiacol, phenol, cresols, 4-ethyl guaiacol, 4-ethyl phenol, and syringol. Using the nonpolar column, seven compounds could be identified: 1,2-dimethoxybenzyl alcohol, 1-hydroxy-2-butanone, 1-(2-furanyl)-1-propane, ethisolide, furfuryl acetate, 1,2-dimethoxybenzene, phenyl acetate. The volatile compounds were classified into five groups: phenols, neutral compounds, organic acids, esters and others. The phenols were the main component and comprised 49~65% of the volatile compounds of these vinegars. In the case of bamboo vinegar, the proportion of the phenols in the volatile compounds was lower than that of the two wood vinegars. However, the proportions of the neutral compounds and the organic acids were higher than those of the wood vinegars. Therefore, it seems that these differences of the proportions of the volatile compounds would make a certain difference of a smoke flavor between the bamboo vinegar and the wood vinegars.