• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.87-94
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• 2004

The effects of pretreatment of GAC and dissolved oxygen (DO) on the sorption capacity for ο-cresol were investigated using pretreated GAC under oxic and anoxic conditions. Virgin GAC was used with pretreated GACs by $O_2$, acid and base as sorbents. Sorption capacity of GAC was dependent on the oxygen conditions according to the pretreatment methods. Virgin GAC showed increased sorption capacity when DO was present in the solution, while $O_2$-pretreated GAC did not show any considerable capacity change. Acid- and base-pretreated GACs were relatively more influenced by presence of DO as compared with virgin GAC. Both acid and base-pretreated GACs showed a rapid sorption rate at the initial stage, but as contact time became longer the sorption was slower. Sorbed ο-cresol was extracted with micro-Soxhlet extraction apparatus using the GAC separated from the rate experiments. Within 1 hour both acid and base-pretreated GACs showed the decrease in extraction efficiencies under both oxic and anoxic conditions. After 1 hour such a trend (the increase as contact time was longer) was not observed and showed relatively constant efficiencies of 35∼50%. According to the results of this study $O_2$contacted with GAC before sorption as well as DO present in the solution during sorption could influence the GAC sorption capacity.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.381-385
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• 2010

Five types of determination methods including the Soxhlet method as well as 3 kinds of extraction solvents, were used for the determination of accurate crude fat contents in wheat flour and 5 kinds of dry noodles. According to the results, crude fat contents were 0.09~1.37% in the wheat flour and 0.07~1.36% in the dry noodle samples. This variation resulted from the types of lipids in the wheat flour and various kinds of dry noodles. Nutrition facts labels showing crude fat contents in the 5 kinds of domestic dry noodle samples indicated levels of 0~1.5%. Lipid composition and content were determined in order to investigate these differences. The results indicated free lipid at 1.02% and bound lipids at 0.21% in the wheat flour, and free lipids at 0.95~1.01% and bound lipid at 0.21~0.25% in the wheat flour. Polar and nonpolar lipid contents were also measured in all samples. Neutral lipid, glycolipid and phospholipid contents in the free lipid were 58.5%, 33.6%, and 8.6% in the wheat flour, and 49.2~58.2%, 33.3~41.6%, and 8.5~9.3% in the dry noodle samples, respectively. For bound lipids, amounts were 16.7%, 33.5%, and 49.5% in the wheat flour, and 13.2~15.3%, 35.6~45.7%, and 41.6~49.4% in the dry noodle samples, respectively. Based on these results, an acid hydrolysis methods should be used to determine accurate crude fat contents in wheat flour and dry noodles.

• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.172-177
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• 1971

The amount of the milk clotting enzyme which is produced by Dothiorella ribis in wheat bran was 950 Soxhlet units per gram of wheat bran. The milk clotting activity of this enzyme was increased by the elevation of clotting temperature and by the increase of the addition of $CaCl_2$ to milk. It was also increased when the pH of milk was lower than that of the fresh milk. When milk was diluted by distilled water, the milk clotting activity of the enzyme was decreased. And its milk clotting activity was good when milk was pasteurized at low temperature. The enzyme of Dothiorella ribis has larger proteolytic activity per Soxhlet unit than that of the milk clotting enzyme of Mucor pusillus Lindt. This enzyme was rather stable between pH 6 and pH 8 when it was conditioned for ten minutes. The heat stability of enzyme was tested by treating it under the condition for $10{\sim}60$ minutes. And the enzyme was stable under the temperature of $45^{\circ}C$. Also the recovery of protein as a form of curd was 76.2 percent to the total protein content of milk.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.40-51
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• 2013

In order to develop a quantitation method for Perfluorooctanesulfonic acid(PFOS) contained in plastics that are mainly used in electric and electronic equipment, this study consisted of conducting method validations with LDPE samples using soxhlet solvent extraction and LC/MS. As a result, the limits of detection and quantitation (LOD, LOQ) were $2.58{\mu}g/L$ and $7.82{\mu}g/L$, respectively. Additionally, the recovery was 96-102%. For the correlation coefficient of LC/MS, the $r^2$ value was 0.9992 in the concentration range of $7.82-100{\mu}g/L$, which confirmed its linearity. Furthermore, for the standardization of the analysis method for PFOS in electric and electronic equipment to correspond to EU environmental regulations, we conducted a proficiency test with a number of domestic and international testing laboratories. Three of the ten testing laboratories that participated in the proficiency test submitted outliers. Accordingly, we examined the cause of the outliers using the $^{19}F$ NMR, finding that the main cause was an error in the processing of the results for isomers in PFOS that existed in standard solutions and samples.

• Food Science and Preservation
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• v.10 no.3
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• pp.370-375
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• 2003

To obtain the oil sesame, walnut, whole wheat, and rice bran were extracted for 1, 3, or 6 hr by a shanking water bath(35$^{\circ}C$ and 100 rpm), and by soxhlet extractor(80$^{\circ}C$) for 1, 3 or 6 hr, respectively. The highest yield of extracted oil was obtained from the walnut(63.07％ weight) and the whole wheat showed the lowest extraction yield of oil(1.13％ weight). Major fatty acids from the extracted oils were linoleic, oleic, and palmitic acid. The maximum contents of total phytosterol in sesame, walnut, whole wheat, and rice bran were 0.44, 1.57, 2.25, and 2.03(％ weight), respectively. Besides, total tocopherol contents in sesame, walnut, whole wheat, and rice bran were maxima 3.42, 0.16, 2.92, and 0.07(％ weight), respectively. From the extracted oils, structured lipids(SL) were synthesized by the interesterification reaction with conjugated linoleic acid(CLA) in a shanking water bath at 55$^{\circ}C$. When the reactions(1:3 substrate molar ratio, extracted oil:CLA) were conducted for 24 hr, maxima 23.75 mol％ of CLA incorporation was obtained from walnut oil and, in other cases, 16.28 - 19.15 mol％ of CLA was found in the produced SL triacylglycerol molecules.

• Preventive Nutrition and Food Science
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• v.22 no.3
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• pp.237-240
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• 2017

Amygdalin contents of the seeds, endocarps, and mesocarps from three peach cultivars (i.e., Stone Peach, Hikawa Hakuho, and Bakhyang) were measured at three stages of fruit development (stone-hardening, fruit enlargement, and ripening). The peach samples were dried and defatted with a Soxhlet apparatus, reflux extracted with methanol, and analyzed using reverse phase high-performance liquid chromatography. During all fruit development stages, the amygdalin contents in the seeds were higher than those in the endocarps and mesocarps. The amygdalin contents of the Stone Peach were comparatively higher than the Hikawa Hakuho and Bakhyang (P<0.05). Further, the amygdalin contents during ripening were very low or not detected. Overall, the amygdalin contents of the three peach cultivar samples (seed, endocarp, and mesocarp) increased until the fruit enlargement stage and either remained constant or decreased during ripening.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.11-17
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• 2000

There are among the most relevant toxic emissions from incinerators such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs). Induction of cytochrome P4501A1 catalyzed 7-ethoxyresorufin O-deethylase(EROD) activity in mammalian cell culture(EROD bioassay) is thought to be a selective and sensitive parameter used for the quantification of dioxin-like components. In this study, the toxic emissions from several school waste incinerators were evaluated by determination of CYPIA catalytic activity and cytotoxicity using cell culture microbioassay. The incinerator residue and soil samples were collected from the schools located in Kyunggi province from April to June 1999. The samples were extracted in a Soxhlet apparatus using toluene for 20 hours. In order to clean-up, concentrated crude extracts were applied to basic alumina column. The EROD activities of extracts in the H4IIE cells were from 1.91$\pm$0.32 ng-TEQ/g to 24.54$\pm$3.48 ng-TEQ/g of biochemical-TEQ value. In soil samples, CYP1A catalytic activity was 0.09~0.64 ng-TEQ/g. EROD bioassay, seems to be a useful short-term bioassay when information about the biological response of complex environmental samples is needed. Although further study is needed, these results indicate that the potent toxic emissions are produced from school waste semi-incinerators.

• Journal of Environmental Science International
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• v.4 no.3
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• pp.97-97
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• 1995

PCBs have been measured using GC-ECD, GC-MS, GC-ELCD, HPLC, TLC, NMR and Immunoassay. The analysis of PCBs using GC-ECD include the peak pattern method as none derivatization and the Perchlorination method as derivatization. This study was conducted to establish the perchlorination method with Sbcls from PCBs to decachlorinated biphenyl(DCB). The aroclor 1242 of PCBs was chlorinated and then, converted into the DCB which showed a single peak in GC-ECD chromatogram. The detection limit of DCB was 2pg. The quantification detection concentration of PCBs extracted with soxhlet was 0.5ng/g in the soil. PCBs were not detected in the suburban soil, but 174ng/g in the soil of industrial complex. Mean PCBs concentration of Shinchun stream at Kumho river and Jinchun stream at Nakdong river was calculated average 낙ngjg in 각e sediment. PCBs concentration in the sediment of Kumho river near 2-7km from conjunction with Nakdong river was average 154ng/g. PCBs concentration in the sediment of Nakdong river near conjunction with Kumho river was average 159ng/g.

• Journal of Environmental Science International
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• v.4 no.3
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• pp.249-258
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• 1995

PCBs have been measured using GC-ECD, GC-MS, GC-ELCD, HPLC, TLC, NMR and Immunoassay. The analysis of PCBs using GC-ECD include the peak pattern method as none derivatization and the Perchlorination method as derivatization. This study was conducted to establish the perchlorination method with Sbcls from PCBs to decachlorinated biphenyl(DCB). The aroclor 1242 of PCBs was chlorinated and then, converted into the DCB which showed a single peak in GC-ECD chromatogram. The detection limit of DCB was 2pg. The quantification detection concentration of PCBs extracted with soxhlet was 0.5ng/g in the soil. PCBs were not detected in the suburban soil, but 174ng/g in the soil of industrial complex. Mean PCBs concentration of Shinchun stream at Kumho river and Jinchun stream at Nakdong river was calculated average 낙ngjg in 각e sediment. PCBs concentration in the sediment of Kumho river near 2-7km from conjunction with Nakdong river was average 154ng/g. PCBs concentration in the sediment of Nakdong river near conjunction with Kumho river was average 159ng/g.

• Journal of Nutrition and Health
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• v.11 no.1
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• pp.9-16
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• 1978

A Comparison of the analysis of the green and roast coffee of Arabica and Robusta compositions and regular instant coffee has been investigated by chromatography. The coffee oil were obtained by extracting the green and roast coffee with ethyl ether by soxhlet methood. Instant coffee samples were accurately weighted into 100ml beaker (ca. 0.5g regular coffee and 1.5g decaffeinated coffee) and add ca. 50ml water, heat and boil, remove from heat, and mechanically stried ca. 15min. and filtered of one sample and another sample were without filtrated and proceed with liquid chromatographic separation. The fatty acid compositions of green and roast coffee were compared by gas liquid chromatography and general chemical compositions of sample were analysed. Some similarities between green and roast coffee fatty acids were found in the case of green and roast coffee of both kinds acid methyl esters. They contained stearic, oleic, linoleic, and unknown fatty acid, and palmitic ana linoleic acid were rich.