• The Korean Journal of Food And Nutrition
• /
• v.11 no.5
• /
• pp.493-498
• /
• 1998

An attempt was in this to analyzer volatile flavor components of sancho(Zanthoxylum schinfolium). Essential oils in sancho tree and fruit isolated by a simulataneous steam distillation (SDE) methods using n-pentane/diethyl ether as solvent. A total of 57 and 44 components were identified by gas chromatography(GC) and combined gas chromatography spectrometry (GC-MS), respectively. Granyl acetate(29.23%) geraniol (6.80%, p-isopropyl-2-chclohexenone(5.53%), phellandral (4.10%) in sancho fruit and 4, 6, 6-trimethyl-bicyclo(7.47%), T-carvelo(4.60%, ${\alpha}$-cypernone(3.58%) in sancho tree were found to be major volatile flavor. 22 compnents including myrcene, limonene, 1, 8-cinol in sancho fruit and 10 components including 4-(1-methylethyl)-cyclohexanol, methyl undecyl ketone in sancho tree were identified. The contents of unsaturated fatty acids of palmitic acid(24.34%), myristic acid(3,68%) in sancho tree was higher than that of the sancho fruit.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.97.2-97
• /
• 2001

This work is concerned with the improvement of the productivity and the product quality in the polymerization reactors by using model-on-demand predictive control(MoDPC). This technique is applied to a continuous styrene polymerization reactor and a semibatch methyl methacrylate (MMA)/vinyl acetate(VAc) copolymerization reactor. The regress is constructed with the most influential variables the conversion and the jacket inlet temperature for the styrene polymerization reactor, and the free volume and the reactor temperature for the MMA/VAc copolymerization reactor through open loop operations. From the simulation results for setpoint tracking and disturbance rejection problems, it is demonstrated that the MoDPC shows ...

• YAKHAK HOEJI
• /
• v.38 no.4
• /
• pp.410-417
• /
• 1994

As one of the studies for Korean cultivated Rhubarb, which has been used stomachic bitter, laxative and purgative, etc, MeOH extract of the leaves was fractionated with ether, ethylacetate. From the ether fraction of MeOH extract, two anthraquinone derivatives, 1,6,8-trihydroxy-3-methyl anthraquinone(emodin, $C_{15}H_{10}O_5$), 1,6,8-trihydroxy-3-hydroxymethyl anthraquinone (citrerosein, $C_{15}H_{10}O_6$) and from the ethyl acetate fraction of MeOH extract, one anthraquinone derivative, emodin-8-${\beta}$-D-glucopyranoside$(C_{21}H_{20}O_{10})$ were isolated and identified through the physico-chemical properties and spectroscopic evidences(UV, IR, NMR, Mass), respectively.

• Korean Journal of Pharmacognosy
• /
• v.38 no.1
• /
• pp.76-83
• /
• 2007

In this study, three triterpenoids, two steroids and nine flavonoids were isolated from the leaves of Alnus firma Sieb. et Zucc. On the basis of spectroscopic evidences, the structures of these compounds were established as ${\beta}$-amyrin acetate, ${\beta}$-amyrin, ${\beta}$-sitosterol, alnustic acid methyl ester, ${\beta}$-sitosterol glucoside, pinocembrin, alnustinol, quercetin, quercetin-3-O-${\alpha}$-L-arabinofuranoside, quercetin-3-O-${\alpha}$-L -rhamnopyranoside, quercetin-3-O-${\beta}$-D-glucopyranoside, myricetin-3-O-${\beta}$-D-galac-topyranoside, (+)-catechin and (-)-epicatechin.

• Journal of Nutrition and Health
• /
• v.19 no.3
• /
• pp.169-176
• /
• 1986

The effect of riboflavin feeding on lipid emtabolism in rat were studied. 70 male Sprague-Dawley rats were divided into 7 diet group ; control, riboflavin, cholesterol, MLHP (methyl linoleate hydroperoxide) cholesterol plus MLHP, cholesterol plus riboflavin, cholesterol plus MLHP plus riboflavin. After 4 weeks formular feeding sera of animals were collected, then checked cholesterol, triglyceride, phospholipid levels and lipoprotein by use of cellulose acetate papter. The results were as follows ; 1) Marked increase of triglyceride and phospholipid levels were found in the group feeding with cholesterol, cholesterol plus MLHP. 2) Combined riboflavin feeding prevented the increase of triglyceride and phospholipid levels in the group of cholesterol, cholesterol plus MLPH. 3) Also combined riboflavin feeding prevented the increase of $\beta$-lipoprotein fraction in cholesterol feeding group. Our results demonstrate that riboflavin has an inhibitory effects on the derangements of lipid metabolism due to administration of cholesterol, cholesterol plus MLHP.

• Archives of Pharmacal Research
• /
• v.27 no.2
• /
• pp.164-168
• /
• 2004

The chromatographic separation of the MeOH extract of the aerial parts of Solidago virga-aurea var. gigantea $M_{IQ}$ . (Compositae) led to the isolation of six terpenoids and four phenolic compounds, trans-phytol (1), ent-germacra-4(15),5,10(14 )-trien-1$\alpha$-ol (2), $\beta$-amyrin acetate (3), ent-germacra-4(15),5,10(14)-trien-1$\beta$-ol (4), $\beta$-dictyopterol (5), oleanolic acid (6), kaempferol (7), kaempferol-3-O-rutinoside (8), methyl 3,5-di-O-caffeoyl quinate (9), and 3,5-di-O-caffeoyl quinic acid (10). Their structures were established by chemical and spectroscopic methods. Compounds 4, 5, and 10 showed moderate cytotoxicity against five cultured human tumor cell lines in vitro with its E $D_{50}$ values ranging from 1.52∼18.57 $\mu\textrm{g}$/mL.L.

• Journal of Food Hygiene and Safety
• /
• v.9 no.2
• /
• pp.89-94
• /
• 1994

A simple, safe, and sensitive gas chromatographic method using packed column and electron capture detector to analyze 2, 4-D herbicide in imported lemon, grapefruit, and orange was described and its usefulness evaluated. In this scheme of analysis the acid herbicide was converted into its alkyl esters by an one-step reaction prior to analysis. The herbicide in the fruits was extracted with ethyl acetate and partitioned against dichloromethane for purification, and the extracts finished partitioning were derivatized with alcohol, using sulfuric acid as a catalyst to form the corresponding alkyl derivatives. The analytical scheme studiedwas found to be applicable for the herbicide in the fruits without a column clean-up procedure. The mean recoveries of the herbicide for lemon samples fortified at 0.1 mg/kg and 1.0 mg/kg were 93% and 95%, respectively. The detection limit was 0.5 $\mu\textrm{g}$/kg for 2.4-D methyl ester.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.51 no.7
• /
• pp.279-286
• /
• 2002

Linear and nonlinear complex permittivities were measured for copolymers of vinylidene cyanide(VDCN) with vinyl acetate(VAc), vinyl propionate(VPr), vinyl bezoate(VBz), styrene(St) and methyl methacrylate(MMA). Experimental results are well fitted by the function (equation omitted) except at low frequency where dc conduction dominates. The analysis of dielectric relaxation mechanism by combined knowledge about linear and nonlinear dielectric permittivities and dipoles give us informations about electrical and thermal motions in these copolymers. According to the analysis it could be found that the variation for temperature of the dielectric relaxation strength in these copolymers is related to the interaction between dipoles and the nonlinear dielectric effect factor R$_{s}$ is proportional to square of the dipolar correlation factor R$_{p}$././.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.10 no.1
• /
• pp.49-74
• /
• 1984

Rheology of gels prepared with stearyl dimethyl benzyl ammonium hectorite (SDBAH) and various polar additives in n-butyl acetate was investigated by measuring the viscosity and rheogram. Including generally recognized polar additives, additional studies on the rheogram and viscosity were made with ether-type methyl cellosolve and carbitol, with dimethyl sulfoxide (DMSO) having sulfonyl group, and furthermore with above-mentioned polar additives containing small quantity of water, It was observed that molecular size, dipole moments and dielectric constants of polar additives had a great influence on viscosity increase and rheology of SDBAH gel, and the increase of SDBAH interlayer spacing was important factor in gel formation and viscosity change. It was also shown that thixotropy effect was increased with the increase of polar additive concentration, finally changed to rheopexy from thixotropy as the concentration of polar additives was increased more than about 40% of SDBAH weight. In addition thixotropy changed to rheopexy as the increase of shear rate. It was further found that the aqueous solutions of polar additives (water content, 5-25%) had more effects on rheology than additives without water, and particularly 95clo DMSO solution was the most effective. And the optimum concentration of polar additives showing maximum viscosity in the same SDBAH concentration system was examined.

• Archives of Pharmacal Research
• /
• v.17 no.3
• /
• pp.175-181
• /
• 1994

The solid-phase extraction (SPF) with subsequent tert-butyldimethylsilyl (TBDMS) derivatization was investigated for the rapid profiling and screening of various carboxylated non-steroidal antiinflammatory drugs (NSAIDs) simultaneously in biological fluid samples. Compared to the conventional SPF in adsorption mode using Chromosorb 102, Chromosorb 107, Carbopak B and Thermosorb, the SPF in partition mode using Chromosorb P as the adsorbent, and ethyl acetate/methylene chloride as the eluting solvents provided hightest overall recovenies of the NSAIDs from aqueous solutions with good precision. The solid-phase extracted NASIDs were silylated with N-methyl-N-(tert-butyldimethylsily)trifuoroacetamide to TBDMS derivatives and directly analyzed by capillary gas chromatography and gs chromatography-mass spectrometry. The usefulness of the present method was examined for the profilling and screening of saliva, serum and urine samples for various NSAIDs simultaneously.