• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.398-402
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• 2004

Safrolechitosan (SaCs) and eugenolchitosan (EuCs) were synthesized and characterized to increase water solubility and functionality of chitosan. Product impurities were removed by Soxhlet apparatus using methanol to obtain final product with high purity. Using Ubbelohde viscometer, molecular weights of chitosan, EuCs, and SaCs were determined as $1.2{\times}10^{5}\;Da,\;7.8{\times}10^{5},\;and\;7.5{\times}10^{5}\;Da,\;respectively$. IR spectrum of SaCs revealed chemical shift of amide II band ($1,553cm^{-1}$) of chitosan grafted by safrole caused by generation of covalent bond between primary amino of chitosan and double bond of safrole. Due to graft reaction of safrole onto chitosan, vinyl bands ($1,611\;and\;1,442cm^{-1}$) of safrole disappeared. In graft reaction of eugenol onto chitosan, shift of amide II band ($1,553cm^{-1}$) and disappearance of vinyl band were observed. On $^{1}H-NMR$ spectrum of EuCs, $H_{2}C=CH-$ peak in eugenol (monomer) disappeared, whereas $-H_{2}C-CH_{2}-$ peak appeared. Above results indicate safrole and eugenol were successfully grafted onto chitosan.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.3 s.58
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• pp.161-171
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• 2006

In this study, we investigated the whitening and anti-oxidant activity of 37 Jeju island native plants. The active ingredients of the plants were prepared by methanol extraction. Whitening activity of plant extracts was examined from the inhibitory effect of tyrosinase and the inhibition of melanin synthesis of the B16-F1 cell line. Their anti-oxidant activity was measured by electron donating ability of DPPH (1,1-diphenyl-2-picrylhydrazyl) and ROS (reactive oxygen species) scavenging activity in V79-4 lung fibroblast cells using DCF-DA (dichlorofluorescin diacetate). Cytotoxicity of the extracts on cell s based experiments was investigated by MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) assay. Also, the toxicity test using a rabbit and the human skin patch test were carried out for examining the safety of the extracts which showed the high whitening activity. It is interesting that the extracts of Lespedeza cuneata, Ligustrum lucidum (stem), Morus bombycis (stem) and Prunella vulgaris var. lilacina showed both potent whitening and anti-oxidant activities.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.530-536
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• 2013

Vegetable oil-based dimer acid derivatives were prepared through a two-step procedure and their lubricating properties for diesel fuel were evaluated using high frequency reciprocating ring (HFRR) method to investigate wear scar diameter (WSD). Diels-Alder reaction at an elevated temperature transformed fatty acid to dimer acid, subsequently converted into dimer acid derivatives by esterification with methanol. It should be noted that the derivatives were dissolved well in diesel oil up to 1 wt%. After adding 120 ppm of the derivatives to pure diesel, the WSD significantly decreased to $300{\sim}05{\mu}m$, compared to $552{\mu}m$ of WSD in pure diesel. Dimer acid derivatives having carboxylic acid show superb in lubricating property which does not depend on the alkyl group in the derivatives.

• YAKHAK HOEJI
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• v.36 no.1
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• pp.1-6
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• 1992

Irradiation of phenolbetaine in a stream of nitrogen produced 8,14-cycioberbine[1]. Compound[1] was treated with 10% HCl solution to give the 8-hydroxycycloberbine[2] in 67.7% yield. Subsequently addition of ethylchloroformate to the compound[2] gave rise to the 8-hydroxy-7-ethylcarboxy-9, 10-dimethoxy-2, 3-methylenelioxy-13-oxo-norochotensane[3] in 78% yield. Treatment of the compound[3] with bis-(2-chloroethyl)amine then lead to the 7-bis(2-chloroethyl)carbamyl-norochoteneare[4]. On the other hand the compound[5], which is the 8-methoxynorochotensane, was derived when compound[1] was treated with methanol in a few drops of BF. Treatment of the compound[6], and the compound[7], 7-bis(2-chloroethyl)-carbanyl-8-methoxy-norocheyensane, was then synthesized by reaction of the compound[6] with bis(2-chloroethyl) amine. In the other synthetic pathway when compound[5] was treated with $POCl_3$ in dried benzene, 13-chloro-6-ene-norochetensane[8] with 42% yield was formed. Finally the 13-bis-(2-chloroethyl) amino-8-methoxy-norochotensane[9] was produced when we treated the compound[8] with bis-(2-chloroethyl) amine. In another pathway, reaction between phenolbetaine which is the precursor of the compound[1] and benzoylchloride in dried chloroform gave us the 5,6,7 trihydro-2, 3-methylene-dioxy-9-chloromethyl-10, 11-dimethoxyphenylisoquinoline-8-benzoate[10] in 73% yield. The results of biological activities for these compounds are also presented in Table I and II.

• Polymer(Korea)
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• v.30 no.1
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• pp.75-79
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• 2006

Silica nanoparticles for polymeric dental restorative composites were prepared by Stober method, and then the effects of surface treatment of silica particles with Lmethacrylofpropyltrimethofsilane $(\gamma-MPS)$ on the dispersity of the silica particles in the organic matrix was investigated. Particles having various average size were prepared by using controlled amounts of tetraethylorthosilicate(TEOS), water, and catalyst and by changing solvent used for reaction. The site of particles prepared by using methanol as solvent was smaller than that prepared by using ethanol as solvent. In addition, the size of particles was increased by decreasing amounts of water and by increasing amounts of TEOS and catalyst. Hydrophobic silica nanoparticles was prepared by reacting hydrophilic nanoparticles with $\gamma-MPS$ to improve interfacial properties with organic matrix. Amounts of $\gamma-MPS$ per unit mass of the particles was increased by decreasing particle size. even though the amount of $\gamma-MPS$ per specific surface area were nearly the same regardless of the particle size. The dispersity of the silica particles in the organic matrix was improved when the surface treated silica particles were used for preparing the polymeric dental restorative composites.

• Analytical Science and Technology
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• v.25 no.1
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• pp.25-32
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• 2012

Isotope dilution mass spectrometry (ID-MS) based on liquid chromatography tandem mass spectrometry (LC/MS/MS) was developed for the accurate determination of sorbic acid in tea-drink. An isotope analogue of sorbic acid, $^{13}C_2$-sorbic acid, was obtained by custom synthesis. MS was operated in the negative mode with selected reaction monitoring (SRM) mode of $[M-H]^-$ ${\rightarrow}$ $[M-CO_2H]^-$ channel at m/z 111 ${\rightarrow}$ 67 for sorbic acid and at m/z 113 ${\rightarrow}$ 68 for its isotope analogue. Chromatographic separation was accomplished with a C18 column and an isocratic mobile phase of 55% of 50 mM ammonium acetate (pH 4.5) and 45% of methanol. Homogeneous reference materials were prepared for validation of this method, including repeatability and reproducibility tests, by fortifying tea-drink with sorbic acid in our laboratory. Repeatability and reproducibility studies showed that the ID-LC/MS method is a reliable and reproducible method which provides less than 3.8% of relative standard deviation (RSD) for the analysis of sorbic acid.

• 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.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.245-248
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• 2014

Trafficking of viral glycoproteins to the cell surface results in syncytium formation in baby hamster kidney (BHK) cells infected with Newcastle disease virus (NDV). An extract from the medicinal Areca catechu L plant inhibited not only syncytium formation, but also trafficking of the hemagglutinin-neuramidase (HN) glycoprotein to the cell-surface. The viral glycoprotein was processed within the endoplasmic reticulum during transit to the cell membrane. Fungal extracts showed inhibitory activities ($IC_{50}10{\mu}g/mL$) against ${\alpha}$-glucosidase. These results suggested that A. catechu L. extracts inhibited the cell-surface expression of NDV-HN glycoprotein without significantly affecting HN glycoprotein synthesis in NDV-infected BHK cells.

• Polymer(Korea)
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• v.25 no.4
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• pp.496-502
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• 2001

Thermally stable polyquinonediimines(PQDI) containing di-azobenzene in the side chain were synthesized by means of condensation polymerization under $TiCl_4$. The synthesized monomers and polymers were identified by FT-IR, $^1H-NMR$, and elemental analysis. Especially, the polymerization of PQDI was confirmed by the double-bonding peak of >C=N appearing near 1625cm$^{-1}$ in FT-IR spectrum. PQDI with di-azobenzene group in one side chain was insoluble in methanol, acetone and non-polar solvents having big dielectric constant, but had good solubility in polar solvents having small dielectric constant. Molecular weight distribution of PQDI measured by GPC was 1.38. It was confirmed to be amorphous polymer through X-ray diffraction by the appearance of the halo in case of PQDI containing di-azobenzene in the side chain. The glass transition temperature ($_g$) of synthesized polymer was measured to be 116$^{\circ}C$ by differential scanning calorimetry. The SHG value for ${\chi}^{(2)}$ was 1.2 pm/V (${\lambda}$ = 1.542 ${\mu}$m). The SHG value slightly decreased in an early stage but showed temporal stability after 20 hours.

• Proceedings of the Ginseng society Conference
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• 1974.09a
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• pp.101-113
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• 1974

The radioactive compound sodium $acetate-U-C^{14}$ (C-14 acetate) was administered to two- and four-year-old July and September American ginseng (Panax quinquefolium L.) plants and cuttings. The C-14 acetate uptake was approximately $99\%.$ The autoradiochromatograms suggest that the saponins(panaquilins) isolated by preparative thin-layer chromatography contained impurities, especially those isolated from the leaf and stem extracts. The root and fruit methanol extracts yielded relatively pure saponins. The large amounts of panaquilin B and its proximity to panaquilin C on preparative thin-layer plates resulted in some admixing. The average concentration $(\%$ plant dry weight) of semipurified saponins were high in the leaves $(13.8\%),$ compared to fruits $(9.8\%),\;stems\;(7.9\%)\;and\;roots\;(6.3\%).$ The average percentage of C-14 acetate incorporation into panaquilins was $4.8\%.$ The average percentage of C-14 acetate incorporation into panaquilins B and C was higher $(1.40\%\;and\;1.13\%,$ respectively) than that into panaquilin C, (d), G-1 and G-2 $(0.75\%,\;0.65\%,\;0.13\%\;and\;0.53\%,$ respectively). Panaquilin synthesis may be depending upon the part collection period and age of the plant. The average percentage of C-14 acetate incorporation into panaquilin B is high in roots $(0.58\%)\;and\;stems\;(0.48\%);$ that into panaquilins C and (d) high in leaves $(0.40\%\;and\;0.45\%,$ respectively); and that into panaquilin E high in roots and leaves $(0.55\%\and\;0.50\%,$ respectively). Panaquilin G-2 was synthesized in all parts of plants. The panaquilins appear to be biosynthesized more actively in July than September (exception-panaquilin G-l). Panaquilins B, C and G-1 may be biosynthesized more actively in four-year-old plants and panaquilins (d) and E more actively in two-year-old plants. The results from expectance with cuttings suggest that the panaquilins are synthesized de novo in the above-ground parts of ginseng plants, and that panaquilin G-l may be synthesized de novo in the leaf. It is known from the tissue culture studies that panaquilins are produced by leaf, stem and root callus tissues and callus-root cultures of American and Korean ginseng plants. Panaquilins may actively be synthesized de novo in most any cell or organ of the ginseng plants. It was verified that C-14 acetate was incorporated into the panaxadiol portions of the panaquilins of two-year-old plants (sp. act., 0.56 $m{\mu}Ci/mg$) and four-year-old plants (sp. act., 0.54 $m{\mu}Ci/mg$).