• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.235-240
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• 1995

Volatile components and fusel oils of sojues and mashes brewed by four different traditional methods such as Andong soju, Moonbaeju, Leekangju, Jindo-hongju were studied. Fusel oil contents of mashes were in the range of $0.09{\sim}0.32{\;}mg/ml$, but those of sojues were increased to reach the range of $0.35{\sim}0.87{\;}mg/ml$. Fusel oil contents of Moonbaeju and Andong soju were lower than those of other sojues. Among fusel oils, iso-amyl alcohol content was highest in all sojues and mashes. Thirty-three volatile components were detected in mashes and distillates which were fermented for 16 days. Among them, seven alcohols, seven esters, four aldehydes and one acid were identified. Furfural that was not found in mashes were detected in four type of sojues. Mashes had more various volatile components than sojues had. Higher content of n-hexyl alcohol, acetic acid and phenethyl alcohol were found in mashes while more iso-amyl alcohol were found in sojues.

• Korean Journal of Food Science and Technology
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• v.17 no.4
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• pp.248-252
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• 1985

Prunus tomentosa Thunberg seed was investigated to evaluate its possibility for use as food resources of fats and proteins. The seed contained 40.38% of crude fat and 26.59% of crude protein. The lipid fractions obtained by silicic acid column chromatography were mainly composed of 95.49% of neutral lipids, whereas compound lipids were only 4.51%. Among the neutral lipid components by thin-layer chromatography, triglycerides were 89.86%, sterols, monoglycerides, sterol esters, free fatty acids and diglycerides were 4.14%, 2.98%, 1.77%, 1.07%, and 0.18%, respectively. Oleic acid (65.06-66.05%) and linoleic acid (26.56-28.40%) were the main fatty acids in the total lipid, neutral lipid and triglyceride fractions. In the glycolipid and phospholipid fractions, predominant fatty acids were oleic acid (40.55-51.46%), linoleic acid (20.26-30.89%) and palmitic acid (17.64-21.43%). The extractability of salt soluble protein of seed was 60%, and recovery rate of main protein fraction separated by Sephadex G-200 was about 46.5%. The electrophoretic analysis showed 7 bands in seed protein.

• Korean Journal of Food Science and Technology
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• v.13 no.1
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• pp.30-36
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• 1981

Neutral lipids of the total lipid extracted from 4 representative varieties of barley grown in Korea and their corresponding malt were studied. Total lipids of barley and malt were solvent extracted with chloroform:methanol:water (1.0 : 1.0 : 0.9, v/v), The total lipids were fractionated into neutral and polar lipids by silicic acid column chromatography, and neutral lipids fraction was separated by thin layer chromatography and quantitated by TLC scanner. The fatty acid compositions was determined by gas liquid chromatography. The average content of total lipid in the 4 barleys and their malts were 3.3 and 2.9%, and average of neutral lipids content in the barley and malt lipids were 73.8 and 68.5%, respectively. Among the neutral lipids, triglycerides and free fatty acids were the major components, and triglycerides content decreased and free fatty acids content increased during malting. Sterol esters, free sterols, 1,3-and 1,2-diglycerides were the minor components of the neutral lipids, and contents of those components showed increasing tendency during malting. The major fatty acid composition of the total lipids were linoleic, palmitic and oleic acids, and in general, the malts had lower amounts of unsautrated fatty acids and high amounts of saturated fatty acids. Fatty acid composition of neutral lipids was of almost the same pattern as that of the total lipids.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.112-116
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• 1997

The enzymatic properties as well as its distribution in the cerebral region and subcellular organells were investigated for the neurosteroid acyltransferase from the bovine brain, which synthesize the fatty acid esters of the neurosteroids. The cerebellum region was the highest in NSAT activity while the cerebrum was the lowest with 50% of the cerebellar activity. The NSAT was found to be mainly localized in the microsomal fraction. The optimal temperature and pH were $40^{\circ}C$ and 4.9, respectively. When $^3H-DHEA$ was utilized as substrate, the $K_m$ and $V_{max}$ was $32.6\;{\mu}M$ and 4.86 nmole/mg protein/h, respectively. Under the same condition pregnenolone$({\Delta}^5P)$ was a competitive inhibitor with $K_i=22.8\;{\mu}M$ and testosterone was a uncompetitive inhibitor with $K_i=22.8\;{\mu}M$. This may suggest that the NSAT has a different conformation in the acylation of the ${\beta}-hydroxyl$ group at C-3 and C-17.

• Korean Journal of Veterinary Research
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• v.40 no.4
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• pp.741-746
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• 2000

We have developed a rapid, simple and precise high-performance liquid chromatographic (HPLC) method using an UV detection system for the determination of new anti-HIV candidates, nineteen KR-V compounds, in rat plasma. We used a analytical columnn of $C_{18}$ ($5{\mu}m$, $250{\times}2.0mm$ I.D.) and a mobile phase of water and ACN mixture (40/60, v/v). Under these conditions, all the KR-V compounds were readily separated from plasma with retention times of 4-12 min. The limits of quantitation for the 19 KR-V compounds were 15-30 ng/ml. The recoveries from the plasma were higher than 85% (C.V.<10%) with exception of KR-V 2, 7 and 15. The compounds KR-V 2, 7 and 15, containing ester moieties, were found to be unstable in plasma. This result suggests that esters, like KR -V 2, 7 and 15, should be excluded from future structure design studies of anti-HIV KR-V agents. In conclusion, the current HPLC method is a valuable analytical tool for investigating the pharmacokinetics of the KR-V series in rats.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.497-503
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• 2008

A variety of techniques has been employed in order to reduce problems caused by the crystallization of paraffin and saturated fatty acid esters in diesel fuel containing biodiesels. Methacrylate copolymers are known as additives which reduce the pour point and cold filtering plugging point (CFPP) of diesel fuels. This paper describes the synthesis, characterization and low temperature properties, having as an initial step the synthesis of the alkyl methacrylate monomers by esterification of methacrylic acid with C12, C18, and C22 fatty alcohols. The copolymerization of these monomers with styrene was then performed, with molar ratios of 30:70, 50:50 and 70:30 for styrene:alkyl methacrylate. All copolymers were characterized by $^1H-NMR$, FT-IR, and gel permeation chromatography (GPC). The poly(styrene-co-alkyl methacrylate)s (PStmSMAn) leads to a large reduction in the pour point and CFPP of poly(styrene-co-alkyl methacrylate) in ultra low sulfur diesel (ULSD) and BD5 with treated 100~5000 ppm of poly(styrene-co-alkyl methacrylate). BD5 fuel containing 5000 ppm of the copolymer (PSt82SMA18) showed a $25^{\circ}C$ and $9^{\circ}C$ reduction in their pour points and CFPP, respectively.

• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.421-427
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• 2012

To improve the lubricity of ultra low sulfur diesel, vegetable oil-based alkanol amide derivatives were prepared and their lubricity properties were studied. To synthesize the alkanol amides, we conducted the amidation reaction of diethaolamine High Frequency Reciprocating Rig (HFRR) and the fatty acid methyl esters, obtained by the continuous transesterification of methanol and several vegetable oil, such as soybean oil, palm oil and coconut oil. The synthesized amides were soluble in ultra low sulfur diesel in the concentration range of ca. 1 wt%; the lubricating properties of ultra low sulfur diesel containing 120 ppm of amides were measured using an HFRR method. It was found that the wear scar diameter in the pure ultra low sulfur diesel decreased significantly from 581 ${\mu}m$ to 305~323 ${\mu}m$ upon the addition of the amides, indicating that lubricating properties of the diesel were improved. On the other hand, the types of vegetable oils did not affect the wear scar diameters, implying that lubricating properties of the diesel did not depend strongly on the structures of alkyl groups of alkanol amide derivatives. When we measured the lubricating properties of the one type of diesels containing various amounts of alkanol amide, we observed that the wear scar diameter decreased drastically with increasing the amide concentration, meaning that the lubricity improved with the amide concentration.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.132-143
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• 1993

Aminomethyl polystyrene resins were prepared either from chloromethyl-resin(Merrifield resin) or from direct amidoalkylation of polystyrene resin. Two kinds of aminomethlyl resin were lengthened with spacer arms via sequential coupling of five ${\varepsilon}$-aminocaproic acids(ACA) respectively. In case of the resin prepared from the Merrifield resin, the amounts of free amino group of the resin were reduced by 25~30% after each coupling of ACA. But the one from direct amidoalkylation showed 3~5% loss after each coupling of ACA. 4-Nitroso-5-aminopyrazole resin was made by reacting ACA spacer arm resin, which was made from direct amidoalkylated resin, with 5-phenyl-7-methylpyrazole [4,3-c][1,2,4]oxadiazin-3-one. Several polymeric active esters of N-blocked amino acids were prepared from the 4-nitroso-5-aminopyrazole bound resins. In anchoring step of the amino acid derivatives on the resin, no substantial effect of bulkiness was found. 4-Nitroso-5-aminopyrazole bound active ester resins were found to be very reactive in N-acylation, The resulting peptides were obtained with 90~95% yield and characterized by NMR and other physical methods.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.289-293
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• 2010

3-MCPD created in manufacture process was regulated in our country about soy sauce and HVP. The latest paper reported that Bound 3-MCPD is created as intermediate. Germany common risk assesment reported that Bound 3-MCPD must be reduced because Bound 3-MCPD can be created in estimation circle when this is hydrolyzed in human body, but the data about the toxity of Bound 3-MCPD is lack. Therefore, We analysis about 209 items food such as soy sauce, seasoning food and meat-eating manufactured goods using bound 3-MCPD analysis method developed recently. As result of survey, bound 3-MCPD detected in 8 items among 44 traditional sauce (0.02~0.28ppm), 8 of soup 12 items (0.01~0.96ppm), in 22 items of sauce 60 items (0.01~0.55ppm), in 16 items of meat-eating manufactured foods 30 items (0.04~0.18ppm), in 20 items of snack cookies 28 items (0.09~1.43ppm), in 8 in roasted oil foods 10 items (0.04~1.22ppm), in 6 items of peanut processed food 10 items (0.06~0.25ppm), in 1 of vegetable cream 15 items (0.05ppm). Detected level was lower than the result of monitored by other countries.

• Korean journal of food and cookery science
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• v.16 no.3
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• pp.221-225
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• 2000

This study was conducted to investigate the usefulness of Perilla frutescens var. acuta as a natural spice. Volatile flavor components of dried Perilla frutescens var. acuta were extracted by supercritical fluid extraction method using diethyl ether as solvent. Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Identification of volatile flavor components was based on the RI of GC and mass spectrum of GC-MS. A total of 24 components, including 4 hydrocarbons, 3 aldehydes, 8 alcohols, 4 esters, 3 acids and 2 miscellaneous components were identified in the essential oils. L-Perillaldehyde was found to be the major volatile flavor component of dried Perilla frutescens var. acuta. The masking effects of Perilla frutescens var. acuta on meaty and fishy flavor were measured by sensory evaluation. Meaty flavor was significantly reduced with the addition of 0.05%, 0.1%, and 0.2% Perilla frutescens var. acuta. The addition of 0.1% and 0.2% powdered Perilla frutescens var. acuta also reduced the fishy flavor of mackerel.