• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.574-587
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• 2014

In this study, vertical distribution patterns of Quercus mongolica Fisch. ex Ledeb. and Q. serrata Murray in Korea were recognized and possibility of introgressive hybridization and gene flow between Q. mongolica and Q. serrata in Mt. Jiri was inferred by flavonoid analyses. The most critical factor on distribution patterns was the altitude in accordance with temperature condition. A zonal distribution was recognized: Quercus mongolica zone in the upper area and Q. serrata zone in the lower area. In Central Korea, the range of vertical distribution of Q. mongolica was above alt. 100m, almost everywhere, whereas that of Q. serrata was from alt. 0 m to alt. 500(-700) m, and the species is rare above that altitude. But in Southern Korea, Q. serrata is found up to above alt. 1,000 m, whereas frequency of Q. mongolica reduces as elevation in decline and the species is rare below alt. 300 m, even though pure stands being formed on higher mountain slope. Altitudinal distribution of the two species, however, overlaps, where the two species occur together. Thirty-seven individuals of Q. mongolica and Q. serrata in Mt. Jiri and other area were examined for leaf flavonoid constituents. Twenty-three flavonoid compounds were isolated and identified; they were glycosylated derivatives of the flavonols kaempferol, quercetin, isorhamnetin, myricetin, and four compounds among the flavonoid compounds were acylated. Kaempferol 3-O-glucoside, quercetin 3-O-glucoside, quercetin 3-O-galactoside and its acylated compounds were major constituents and present in all individuals. Quercus mongolica is distinguished from Q. serrata by the presence of quercetin 3-O-arabinosylglucoside and by high concentration of three acylated compounds, acylated kaempferol 3-O-glucoside, quercetin 3-O-glucoside, quercetin 3-O-galactoside, and by relatively low concentration or lacking of rhamnosyl flavonol compounds. There are intraspecific variations in flavonoid profiles for Q. mongolica and Q. serrata, the flavonoid profiles for individuals of two species in hybrid zone (sympatric zone) tend to be similar to each other, qualitatively and quantitatively. These findings strongly suggest that gene exchange or gene flow occurs through the introgressive hybridization between Q. mongolica and Q. serrata in Mt. Jiri. Therefore, Quercus crispula, occupying morphologically intermediate position between Q. mongolica and Q. serrata, is suspected of being a hybrid taxon of two putative parental species.

• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.522-532
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• 1985

The reactions of p-nitrophenyldiphenylphosphate (p-NPDPP) with anions of benzimidazole (BI) and its 2-alkyl derivatives (R-BI) are strongly catalyzed by the micelles of cetyltrimethyl ammonium bromide (CTABr). On the other hand, the first order rate constants $(k'_{R-BI^-})$ and the second order rate constants $(k_{m(R-BI^-)})$ of the reactions mediated by R-$BI^-$in the micellar pseudophase are much smaller than those mediated by $BI^-$. In order to explain the slower rates of the micellar reactions mediated by R-$BI^-$, we compared the concentration-ratios ([R-$BI^-$]/[$BI^-$]) with the first order rate constant-ratios $(k'_{R-BI^-}/k'_{BI^-})$ and the second order constant-ratios $(k_{m(R-BI^-)}/k_{m(BI^-)})$ for the reactions taking place in the micellar pseudophase. The rate constant-ratios were much smaller than the concentration-ratios. For example in a 5 ${\times}10^{-4}$M butyl-BI solution, the two ratios were 0.089 and 0.430 (for the first order) respectively, and in a $10^{-4}$M butyl-BI solution the former was 0.100 (for the second order). This predicts that the reactivities of R-$BI^-$ in the micellar pseudophase are much smaller than that of $BI^-$. Based on the values of several kinetic parameters measured for dephosphorylation of p-NPDPP mediated by R-$BI^-$, a schemetic model is proposed. Due to the hydrophobicity and the steric effect of the alkyl substituents, these groups would penetrate into the core of the micelle for stabilization by van der Waals interaction with long cetyl groups of CTABr. Consequently, the movements of R-$BI^-$ bound to the micelle should be restricted, leading to decreased collison frequencies between the nucleophiles and p-NPDPP. We refer this as an "anchor effect". This effect became more predominent when a larger alky group in R-BI was employed and when a greater concentration of R-BI was used.

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.330-337
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• 2011

In this research, the preparation processes for making a series of $\omega$-mercapto alkylamine 1 and $\omega$-mercapto alkanoic acid 2 useful for studying of the self-assembled monolayer(SAM) are described. The preparation methods of the first goal materials, $\omega$-mercapto alkylamines 1 were carried out as follows: First, $\omega$-phthalimide alkanol 3 was synthesized from commercially available potassium phthalimide derivatives and $\omega$-bromoalkanol in DMF at $80{^{\circ}C}$ via substitution reaction. After refluxing $\omega$-phthalimide alkanol 3 with hydrazine hydrate in ethanol followed by treating with c-HCl, $\omega$-aminoalkanol 4 was obtained in 76-98% yield, accompanied with side-product 5. Bromination of hydroxyl moiety of $\omega$-aminoalkanol 4 using aqueous hydrobromic acid furnished $\omega$-bromoamine 6 in 34-97% yields. Substitution reaction 6 with thiourea in 95% ethanol gave $\omega$-aminoalkanthiuronium 7, which was treated with aqueous strong base and aqueous strong sulfuric acid gave desired products, $\omega$-mercapto alkylamines 1 through overall 5 steps. The second target material, $\omega$-mercapto alkanoic acid 2 was prepared via 2 steps. $\omega$-bromo alkanoic acid was reacted with thiourea to give $\omega$-thiourea alkanoic acid 7 in 69-85%, which was treated with aqueous strong base and strong acid to furnish $\omega$-mercapto alkanoic acid 2 in 50-98%. The fabricated long-chain alkylthiol(LCAT) can be used as linkers to immobilize protein, enzyme and various kinds of biomolecules on the surface of metallic materials(Au, Pt, Ti) by SAM, and can be useful chemical tools for the application study on the surface modification of metallic materials.

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.27-36
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• 2015

The improved analytical method with gas chromatography (GC) and GC-mass spectrometry was established to identify and quantify disaccharides and trisacchrides in honey. In this method, the analysis of trimethylsilyl (TMS), TMS-oxime and TMS-methoxime sugars takes into account the determination of a single peak of complete separation on the chromatogram. The number of possible peaks for the qualitative and quantitative determination of TMS, TMS-oxime, and TMS-methoxime sugars was 17, 22, and 25, respectively. This new analytical method allowed for the determination of diand trisaccharides in honey by TMS-oxime and TMS-methoxime derivatives. This study suggested that the improved method is more suitable and precise than the other analytical methods for the simultaneous determination of sugars in honey.

• Journal of Food Hygiene and Safety
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• v.33 no.4
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• pp.266-271
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• 2018

The Ministry of Food and Drug Safety (MFDS) is amending its test methods for health-functional foods (dietary food supplements) to establish regulatory standards and specifications in Korea. In this regard, we continue our research on developing analytical methods for the items. Octacosanol is the major component of polycosanol and is a high-molecular-mass primary fatty alcohol, obtained from sugar cane wax. Previous researchers have shown that octacosanol can lower cholesterol and has antiaggregatory properties, cytoprotective uses, and ergogenic properties for human health. Recently, octacosanol products have been actively introduced into the domestic market because of their functional biological activity. We have developed a sensitive and selective test method for octacosanol that the TMS derivatives by means of gas-chromatographic-tandem mass spectrometry (GC-MS). The trimethylsilyl ether derivative of the target analyte showed excellent chromatographic properties. The procedure was validated in the range of $12.5{\sim}200{\mu}g/L$. Standard calibration curves presented linearity with the correlation coefficient ($r^2$) > 0.999, and the limits of detection (LOD) and limits of quantitation (LOQ) were $4.5{\mu}g/L$ and $13.8{\mu}g/L$, respectively. The high recoveries (92.5 to 108.8%) and precision (1.8 to 2.4%) obtained are in accordance with the established validation criteria. Our research can provide scientific evidence to amend the octacosanol test method for the Health-Functional Food Code.

• Tuberculosis and Respiratory Diseases
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• v.59 no.2
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• pp.186-192
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• 2005

Background : Diagnosis of tuberculous pleurisy is sometimes difficult using conventional diagnostic methods. We have investigated the utility of pleural fluid cell $IFN-{\gamma}$ production assay in the diagnosis of tuberculous pleurisy. Methods : We prospectively performed pleural fluid cell $IFN-{\gamma}$ production assay in 39 patients with tuberculous pleural effusions (TPE) and in 26 patients with nontuberculous pleural effusions (NTPE) (13 malignant pleural effusions and 13 parapneumonic effusions). Pleural fluid cells were cultured in DMEM media and stimulated with purified protein derivatives (PPD), and phytohemagglutinin (PHA) for 24 hr. The amount of $IFN-{\gamma}$ released in the culture supernatant was quantitated by $IFN-{\gamma}$ ELISA assay. We have also measured adenosine deaminase (ADA) activities and $IFN-{\gamma}$ concentrations in the pleural fluid. Results : 1) The pleural fluid levels of ADA activity and $IFN-{\gamma}$ concentrations were significantly higher in TPE than NTPE (p<0.01). 2) $IFN-{\gamma}$ production in TPE cells stimulated by PPD ($755,266{\pm}886,636pg/ml$) was significantly higher than NTPE cells ($3,509{\pm}6,980pg/ml$) (p<0.01). By considering the fact that $IFN-{\gamma}$ concentrations over 10,000 pg/ml is a criteria for the diagnosis of TBE, sensitivity and specificity of the test were 97.4 and 92.3%, respectively. 3) The ratios of $IFN-{\gamma}$ production by the stimulation with PPD and PHA (PPD/PHA) were significantly higher in TPE cells ($59{\pm}85$) than NTPE cells ($5{\pm}18$)(p<0.01). Considering the criteria for the diagnosis of TBE as PPD/PHA ratio over 5, sensitivity and specificity of the test were 76.9 and 92.3%, respectively. Conclusion : Pleural fluid cell $IFN-{\gamma}$ production assay may be useful for the diagnosis of tuberculous pleurisy.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.183-190
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• 2004

The major compositions of leaf tea and flower tea were investigated to develope as a new functional tea using Korean native Camellia japonica L. Most of leaf teas, except flower tea, were considered as good materials with basic conditions for tea manufacture because water content was below 6%. Crude protein was the greatest component in roasted young leaf tea (RYLT), crude fats in roasted mature leaf tea (RMLT) and ashes in fermented young leaf tea (FYLT). Caffein were present as the highest amount (5.18%) in steamed mature leaf tea (SMLT), showing less amount than green tea. Catechin were contained as the highest amount in all kinds of teas, especially FYLT was the highest (9.57%). Tannin, which highly related with tea quality including astringent taste, color and perfume, were present as the highest amount in FYLT. Vitamin C was highly detected in the tea from flowers (22.7 mg/l00 g) rather than in the tea from leaves. The content of theanine were found in flower tea by 1,074 mg/l00 g, and had about twofold of FYLT and RYLT. Among free amino acids, glutamic acid and aspartic acid were higher detected in SMLT and RMLT while asparagine was present as higher amounts in RYLT and FYLT, expecting these components can improve tea taste. Nucleic acids and their derivatives including GMP, hypoxanthine and AMP were detected as the higher amounts by 7.86, 8.57, and $12.67\;{\mu}mol/g$, respectively, however IMP content was even reduced by all manufacturing processes. In all kinds of tea, sugars such as glucose, fructose, sucrose and maltose were detected, specially glucose and fructose were found as highest amount in RFT by 65.5 and 59.6 nmol/0.1 mg, respectively.

• Journal of Venture Innovation
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• v.1 no.1
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• pp.83-98
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• 2018

This paper makes a theoretical approach to the differences between transaction tax and capital gains tax when the financial instruments are traded and imposed taxes in K-OTC market, a newly emerging off-board market. Since it is difficult to reduce risk to the level which investors would like to pursue - depending on the taxation methods of portfolio-composed financial instruments - when it comes to forming a synthetic bond to hedge risk, this paper also seeks for effective taxation methods to make this applicable. First of all, to thoroughly review the taxation balance of synthetic bonds, this paper analyzed the effects of the transaction tax and capital gains tax imposed upon synthetic bonds according to the changes in final stock price and strike price in K-OTC market, and analyzed after-tax profit differences among them depending on whether income tax deduction took place or not. As a result of the research upon the tax gap in transaction tax and capital gains tax according to the changes of final stock prices, it was shown that imposing transaction tax is more likely to be effective for some level of risk hedging with replicating portfolio considering taxation policies and financial markets, since the effect of the transaction tax has a much lower tax gap than that of capital gains tax. In addition, in relation to whether income tax deduction was permitted or not, it was proved that the effect of the transaction tax and the capital gains tax vary depending on the variation in the strike price. Above all, it was shown that if the strike price is lower than the stock price, the transaction tax will be less affected by the existence of income tax deduction than the capital gains tax, while both will be equally affected by the existence of income tax deduction if the strike price is higher than the stock price. Further study would be to demonstrate the validation of this in the K-OTC market with actual financial instruments and, also, to seek for a more systematic hedging method by using a ratio analysis approach to the calculation of the option transaction tax

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.200-207
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• 2015

Various natural products or their derivatives, mostly originating from plants, fungi, and bacteria, have been exploited as therapeutic drugs to treat various human diseases. In addition to previously explored organisms, research on natural compounds has now expanded into unexamined living organisms in order to identify novel bioactive substances. Here, we determined whether or not the larval form of the mealworm beetle Tenebrio molitor, a species of darkling beetle, contains cytotoxic substances that exclusively affect cancer cell viability. Ethanol extract and its solvent partitioned fractions, hexane and ethyl acetate fractions, showed anticancer effects against various human cancer cells derived from the prostate (PC3 and 22Rv1), cervix (HeLa), liver (PLC/PRF5, HepG2, Hep3B, and SK-HEP-1), colon (HCT116), lung (NCI-H460), breast (MDA-MB231), and ovary (SKOV3). Cell death induced by the fractions was a mix of apoptosis, necrosis, and autophagy. The hexane fraction was administered intraperitoneally to nude mice bearing a hepatocellular carcinoma SK-HEP-1 and showed inhibition of tumor growth in vivo. Therefore, we concluded that worm extracts contain cytotoxic substances, which can be enriched by proper fractionation protocols, and further separation and purification could lead to the identification of novel molecules to treat human cancers.

• The Korean Journal of Nuclear Medicine
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• v.35 no.5
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• pp.324-333
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• 2001

Purpose: $^{123}I$-labeled fatty acids have been used in the evaluation of regional myocardial energy metabolism. This study aimed to evaluate the usefulness of $^{123}I$-BMIPP as a liposarcoma-imaging agent. Materials and Methods: We compared in vitro uptakes between liposarcoma(SW872) and glioma(9L) cell lines, and examined biodistribution and in vivo images of $^{123}I$-BMIPP in liposarcoma-bearing nude mice. Cold-BMIPP was labeled with $^{123}I\;using\;Cu^{2+}$ as catalyst. After purification by Sep-pak, radiochemical purity was determined by TLC. We compared cellular uptake between glioma and liposarcoma after incubation of 5, 10, 15, 30, 60, 120, and 180 mins with culture medium containing $^{123}I$-BMIPP. The difference in biodistribution was determined between non-feeding (water only) group for 18 hr and feeding group in normal mice (n=6/group) at 0.5, 2, and 24 hr. In liposarcoma-hearing nude mice model, liposarcoma, SW872, ceil lines were injected subcutaneously into the felt thigh of nude mice. The biodistribution of $^{123}I$-BMIPP was evaluated at 0.5, 2, and 24 hr (n:5 / group) and in vivo Image of $^{123}I$-BMIPP was obtained with gamma camera at 2 and 24 hr in liposarcoma-hearing nude mice. Results: Radiolabeling yield and radiochemical purity were 95% and above 99%, respectively. SW872 cell line showed more increased uptake than 9L with 1.5 times at 180 mins. The clearance of $^{123}I$-BMIPP in various tissues was more delayed in the non-feeding group than in the feeding group, especially at delayed time (24 hr) in normal mice, and the major excreting organ was the gastrointestinal tract. In liposarcoma-bearing nude mice, tumor/blood ratio of $^{123}I$-BMIPP was 0.94, 0.75, and 1.38 and tumor/muscle ratio was 0.66, 1.53, and 1.11 at 0.5, 2, and 24hr, respectively. $^{123}I$-BMIPP was selectively localized in liposarcoma at 24 hr image. Conclusions: These results suggest that $^{123}I$-BMIPP can be used as a liposarcoma-imaging agent.