• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.311-316
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• 2007

Trans fatty acid components separated and quantified using a SP-2560 capillary column in a gas chromatograph (GC) with flame ionization detector (FID). Trans fatty acid and total fatty acid contents were measured in 21 corn oils. Ranges of values for trans fatty acid (tFAs) contents of total fat (as g/100g fatty acids) were com oils $0.65{\pm}0.31$. Corn oils were heated at $175{\pm}5^{\circ}C$ for 5mins $(0{\sim}15\;times)$. The contents of tFAs (g/100) were increased from 0.292 (0 time) to 2.585 (15 times) in com oil. When frying oils (15 times) were incubated at $20{\pm}5^{\circ}C$ for 150 days, the contents of tFAs (g/100g) were increased from 2.585 to 3.683 in com oil. The amounts of tFAs (g) per serving size of frying oils (15 times) were increased from 0.01 to 0.18 in corn oil. The levels of the 18:1 trans isomers increased significantly the time of reusing of com oil.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.11
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• pp.1095-1101
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• 2008

Nonaqueous phase liquids (NAPL) are the continuous source for soil and groundwater contamination. The first objective of the study was to verify the effect of co-injection of cosolvent and air on NAPL removal from soil-column system. The second objective of the study was to investigate the effect of alcohol-partitioning property on the NAPL removal by the co-injection process of cosolvent and air. Enhanced removal of benzene-NAPL by the co-injection process of ethanol and air was also verified within the soilcolumn system. However, the co-injection process of Tert-butanol (TBA) and air showed no enhancement of benzene-NAPL removal. This study found that the viscous pressure of TBA was so higher than the capillary pressure and TBA easily displaced the benzene-NAPL and air present in soil pores. Air of the coinjection process did not work for NAPL removal but hindered NAPL mobilization. NAPL partitioning property and viscous pressure of cosovlent should be considered for application of the co-injection process of cosolvent and air.

• Journal of the Korean Applied Science and Technology
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• v.9 no.2
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• pp.149-156
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• 1992

Levels of total lipids in the seeds of three species of the Pinaceae family were determined and their fatty acid compositions were also analyzed by a gas-chromatograph equipped with a capillary column coated with Carbowax 20M. The results are summarized as follows: Lipid contents of the seeds amounted to 56.9% in P. koraiensis, 29.9% in P. thunbergii, and 21.2% in P. rigida. In all lipids 19${\sim}$20 fatty acid were detected and, surprisingly, fatty acids having ${\Delta}^5$-non-methylene interrupted conjugate double bond such as ${\Delta}^{5, 9}-C_{18:2},{\Delta}^{5, 9, 12}-C_{18:3}\;and\;{\Delta}^{5, 11, 14}-C_{20:3}$ occurred in appreciable amounts. In the lipids of P. koraiensis, the main component was $C_{18:2}{\omega}_6(45.0%)$, followed by $C_18:1{\omega} _9(26.9%)$ and ${\Delta}^{5, 9, 12}-C_{18:3}(14.6%)$, and then ${\Delta}^{5, 9}-C_{18:2}(2.2%)$ and ${\Delta}^{5, 11, 14}-C_{20:3}$ were also present. Levels of saturated fatty acid such as $C_{16:0}\;and\;C_{18:0}$ were as low as 7.5%. The seed oil of P. thunbergii predominantly comprised $C_{18:2}{\omega}_6(45.2%)$, and was then occupied by equal amounts ${\Delta}^{5, 9, 12}-C_{18:3}(18.1%)$ and $C_{18:1}{\omega}_9(18.1%)$. Its ${\Delta}^5, 11, 14}-C_{20:3}(5.8%)$ level was the highest in the samples tested. ${\Delta}^{5, 9}-C_{18:2}(2.8%)$ was also detected with other minor components. In the oils from the seeds of P. rigida, $C_{18:2}{\omega}_6$ was present as a main component, accompanied by $C_{18:1}{\omega}_9(21.6%)$ and ${\Delta}^{5, 9, 12}-C_{18:3}(20.3%)$. The latter showed higher level than in any other samples. A minor component corresponding to ${\Delta}^{5, 9, 12, 15}-C_{18:4}$(not confirmed by GC-Mass) occurred in P. thunbergii and P. rigida.

• Journal of the Korean Applied Science and Technology
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• v.22 no.4
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• pp.323-331
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• 2005

Fatty acid compositions of the seed oils of P. schinseng, A. continentalis and A. sessiliflorus, were analyzed by gas chromatography (GC) equipped with a capillary column. A large unusual peak was observed just before the peak corresponding to oleic acid $(cis-9-C_{18:1})$. This unknown fatty acid was isolated by silver ion chromatography and then derivatized into the picolinyl ester. The mass spectrum of the picolinyl ester showed molecular ion at m/z=373 with other diagnostic ions such as m/z=178, 218, 232, 246, 274, 288, 302 and 344. Characteristic absorption peaks at $720\;cm^{-1}$, $1640\;cm^{-1}$ and $3010\;cm^{-1}$ in IR spectrum indicated the presence of cis-configurational double bond in the molecule. The $^1H-NMR$ spectrum of this acid gave two quintets centered at ${\delta}1.638$ (2H, C-3) and ${\delta}1.377$ (2H, C-4), and two multiplets centered at ${\delta}2.022{\sim}2.047$ (2H, C-5) and ${\delta}2.000{\sim}2.022$ (2H, C-8), and multiplet signals of olefinic protons centered at ${\delta}5.3015{\sim}5.3426$ (C-6, J=9.5 Hz) and ${\delta}\;5.3465{\sim}5.3877$ (C-7, J=9.5 Hz). The $^13C-NMR$ spectrum showed 18 carbon resonance signals including an overlapped signal at ${\delta}29.7002$ for C-12 and ${\delta}29.6520$ for C-13 (or they can be reversed), and other highly resolved signals at ${\delta}33.950$, ${\delta}24.558$, ${\delta}26.773$ and ${\delta}27.205$ due to C-2, C-3, C-5 and C-8 of a ${\Delta}^6-octadecenoic$ acid, respectively. From analysis results this unknown fatty acid could be identified as cis-6-octadecenoic acid. The seed oils of P. schinseng and A. sessiliflorus contained petroselinic acid (59.7%, 56.0%), oleic acid (18.3%, 6.1%) and linoleic acid (16.2%, 30.4%) with small amount of palmitic acid (3.0%, 3.1%) while the seed oil of A. continentalis comprised mainly oleic acid (30.2%), petroselinic acid (29.0%), linoleic acid (24.1%) and palmitic acid (13.1%).

• Analytical Science and Technology
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• v.30 no.6
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• pp.348-354
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• 2017

In this study, patterns of proteome expression were monitored and specifically expressed proteins in human milk were detected in collected human milk after 1 week, 3 weeks, and 6 weeks from delivery. A quantitative shotgun proteomic approach was used to identify human milk proteins and reveal their relative expression amounts. For each sample, two independent human milk samples from two mothers were pooled, and then three replicated shotgun proteomic analyses were carried out. Casein, which is a highly abundant protein in human milk, was removed, and then trypsin was treated to produce a digested peptide mixture. The peptides were loaded in the home-made reversed-phase C18 fused-silica capillary column, and then the eluted peptides were analyzed by using a linear ion-trap mass spectrometer. The relative quantitation of proteins was performed by the normalized spectral count method. For each sample, 81-109 non-redundant proteins were identified. The identified proteins consisted of glycoproteins, metabolic enzyme, and chaperon enzymes such as lactoferrin, carboxylic ester hydrolase, and clusterin. The comparative analysis for the 63 proteins, which were reproducibly identified in all three replications, revealed that 25 proteins were statically significant differentially expressed. Among the differentially expressed proteins, Ig lambda-7 chain C region and tenascin drastically decreased with the delivery time.

• Biomolecules & Therapeutics
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• v.6 no.3
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• pp.289-295
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• 1998

The bioequivalence of two nilvadipine products was evaluated in 16 normal male volunteers (age 22-32 yr, body weight 57-80 kg) following sidle oral dose. Test product was Overca $l_{R}$ tablet (Choong-Wae Pharm. Corp., Korea) and reference product was Nivadi $l_{R}$ tablet (Hyundai Pharm. Corp., Korea). Both products contain 4 mg of nilvadipine. One tablet of the test or the reference product was administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of nilvadipine was accomplished using a validated capillary column GC with electron-capture detection. As a result of the assay validation, the quantiflcation of nilvadipine in human plasma by this technique was possible down to 0.5 ng/ml using 1 ml of plasma. Absolute overall recovery from five replicate analyses of nilvadipine-spiked sample were 88.4$\pm$ 10.24% (mean$\pm$ 5.D.) for human plasma of 10 ng/ml. The coefficients of variation (C.V.) were less than 20% and the actual concentration of nilvadipine measured by GC ranged from 80 to 99% in all plasma. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products (p>0.05); the area under the curve from time zero to 8 hr (AUCo-$_{8 hr}$) (22.8$\pm$5.90 vs 22.2$\pm$6.10 ng . hr/ml), maximum plasma concentration ( $C_{max}$) (10.0$\pm$2.85 vs 9.3$\pm$3.28 ng/ml) and time to reach maximum plasma concentration ( $T_{max}$) (1.2$\pm$0.31 vs 1.3 $\pm$0.47 hr). The differences of mean AU $Co_{8hr}$ $C_{max}$, and $T_{max}$ between the two products (2.25, 7.65, and 10.30%, respectively) were less than 20%. The power (1-$\beta$) and treaeent difference (7) for AU $Co_{8hr}$, and $C_{max}$ were more than 0.8 and less than 0.2, respectively. Although the power for Tmax was under 0.8, Tm\ulcorner of the two products was not significantly different from each other (p>0. 05). These results suggest that the bioavailability of Overeat tablet is not significantly different from that of Nivadil tablet. Therefore, two products are bioequivalent based on the current results.sults.lts.lts.lts.

• Korean journal of food and cookery science
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• v.7 no.1
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• pp.45-51
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• 1991

In this study, several standard fatty acids were analyzed by three analysis instruments. And also, for the two kinds of soybean oils, fatty acids compositions were determined by three instruments. The results were obtained as follows: 1. In the case of Gas Chromatography (GC), standard fatty acids (Myristic, Stearic, Linoleic, Linolenic, Arachidonic acid) were determined with high reproducibility, but oleic acid/elaidic acid were not seperated. By Capillary Gas Chromatography (CGC), most of standard fatty acids were determined with very high reproducibility than saturated fatty acids, and palmitic acid/oleic acid were not seperated. 2. In the analytical ability of cis-trans fatty acids isomer (oleic acid/elaidic acid), CGC was shown better analytical ability of geometrical isomer than HPLC. Oleic acid/elaidic acid were not seperated by packed column (15% DEGS). The rquire time for standard fatty acids analysis was as follows; GC, 7.21 min., CGC, 9.84 min., HPLC, 24.48 min. 3. The major compositions of fatty acids of each soybean oil (CSOY; refined, DSOY; unrefined) by GC and CGC were linoleic acid, oleic acid, palmitic acid, linolenic acid and stearic acid. But in the case of HPLC, palmitic acid/oleic acid were not seperated. Analytical ability of three instruments on fatty acids composition in each soybean oil was same trend as in the standard fatty acids mixture.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1006-1011
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• 1998

Volatile flavor components in three varieties (shingo(niitaka), mansamgil (okusankichi) and chuwhang pears) of Pear (Pyrus pyrifolia N.) were extracted for 24 hours with pentane-diethylether (1 : 1, v/v) using the LLEP (liquid-liquid extraction & perforation). Neutral fraction was separated from the extract and then analyzed by GC-FID and GC/MS equipped with a fused silica capillary column (Carbowax 20M, HP). Individual components were identified by mass spectrometry and their retention indices. The totals of 52, 47 and 22 volatiles were identified in shingo, mansamgil and chuwhang pears, respectively. Ethyl acetate, propyl acetate, hexanal, 1-hexanol, ethyl butanoate, ethyl-3-hydroxy butanoate, ethyl-2-hydroxy propanoate were the main components in each samples, though there were several differeces in composition of volatile compounds. Total contents of volatile components isolated in shingo, mansamgil and chuwhang pears were 6.972, 2.776 and 2.653 mg/kg of pears.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.149-153
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• 1991

Several commercial soybean oils were stored at $20^{\circ}C,\;40^{\circ}C$ and $60^{\circ}C$ with daily exposure of fluorescent light for 12 hours and evaluated their rancidity by headspace gas chromatographic analysis of pentanal and hexanal. The data of gas chromatographic analysis was compared with organoleptic flavor evaluation. For headspace gas chromatographic analysis, the volatile compounds were recovered by porous polymer trap and flushed into a fused silica capillary column at $250^{\circ}C$, The pentanal and hexanal separated were identified by gas chromatography and gas chromatography-mass spectrometric method. The results showed that the contents of pentanal and hexanal were linearly increased during storage for 100 days. A very simple linear relationship was found between organoleptic flavor scores and amounts of two volatile compounds with very high correlation coefficient. A similar linear relationship was also obtained for acid and peroxide value with sensory data. This results suggested the possible implication of pentanal and hexanal as an quality index for rancidity evaluation of soybean oil.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.240-245
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• 2008

The consumption of foods containing trans fatty acids (TFAs) is a matter of concern at present. According to many studies, trans fatty acids (TFAs) may cause illnesses such as the coronary heart disease, diabetes mellitus, large intestine cancer, and breast cancer. They can also raise low density lipoprotein (LDL) cholesterol and reduce high density lipoprotein (HDL) cholesterol. TFAs can also inhibit the synthesis of phospholipids containing polyunsaturated fatty acids in arterial cells. As a consequence the Food and Drug Administration has deemed that saturated fatty acid, cholesterol and trans fatty acid levels be listed on food labels as of 2006. The Korea Food and Drug Administration also has required the listing of trans fatty acid content on food labels since 2007. The aim of this study was to determine the total lipid and trans fatty acid (TFA) contents in retort food, powdered milk, biscuit and pizza products. The number of samples examined were 2 retort food, 6 powdered milk, 7 biscuit and 3 pizza products. The extraction of total lipids in retort food and powdered milk followed the chloroform methanol method. The extraction of total lipids in biscuit and pizza was by the acid digestion method. All samples were analyzed by gas chromatography (GC) using a SP-2560 capillary column and a flame ionization detector. The TFA contents per 100g of sample were 1-2.8% (1.9%) in retort foods, 0.4-2.4% (1.37%) in powdered milk products, 0-2.9% (1.23%) in biscuits, and 2.8-3.45% (3.03%) in pizzas.