• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2178-2182
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• 2011

Recently, the synthesis of ordered macroporous materials has received much attention due to its potential use as photonic band gap materials.$^1$ In this study, we have used the three-dimensional (3D) latex array template impregnated with benzenesulfonic acid (BSA), which is capable of catalyzing the reaction using tetraethyl orthosilicate (TEOS) as a precursor and distilled water. The polystyrene (PS) templates were reacted with TEOS in $scCO_2$ at 40 $^{\circ}C$ and at 80 bar. In the reactor, TEOS was filtrated into the PS particle lattice. After the reaction, porous silica materials were obtained by calcinations of the template. The stability test of the PS template in pure $CO_2$ was conducted before the main experiment. Scanning electron microscopy (SEM) images showed that the reaction in $scCO_2$ takes place only on the particle surface. This new method using $scCO_2$ has advantages over conventional sol-gel processes in its capability to control the fluid properties such as viscosity and interfacial tension. It has been found that the reaction in $scCO_2$ occurs only on the particle surface, making the proposed technique as more rapid and sustainable method of synthesizing inverse opal materials than conventional coating processes in the liquid phase and in the vapor phase.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.223-227
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• 2009

The fruits of Cornus kousa Burg. were extracted with 80% aqueous methanol (MeOH) and the concentrated extract was partitioned with ethyl acetate (EtOAc), n-butanol (n-BuOH), and $H_2O$. From the EtOAc traction, 5 triterpenoids were isolated through repeated silica gel ($SiO_2$), octadecyl silica gel (ODS), and Sephadex LH-20 column chromatography (c.c.). These compounds were determined to be ursolic acid (1), corosolic acid (2), taraxasterol (3), betulinic acid (4), and betulinic aldehyde (5) on the basis of their spectroscopic data including electronic ionization mass spectrometry, ultraviolet spectroscopy, infrared spectroscopy, and nuclear magnetic resonance. This is the first reported isolation of these compounds from this plant. Also, compounds 1, 3, 4, and 5 show a relatively high inhibitory activity against human acyl-CoA: cholesterol acyltransferase-1 (hACAT-1) with inhibition values of $52.8{\pm}0.7$, $91.1{\pm}0.4$, $93.0{\pm}0.7$, and $96.2{\pm}0.2%$ at a concentration of $100{\mu}M$, respectively.

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.76-81
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• 1998

Physical adsorption on a silica gel(pore size of 80 nm, particle size of $10{\mu}m$)has been studied for binary mixture of acetone diluted in $CO_2$ by use of a FTIR transmission technique and we have compared the result of FTIR transmission technique with that of a chromatographic technique. Measurements were made at 313.2 K and under pressures up to 15MPa. As the pressure increases from 0.1MPa, the IA(Integral Absorbance) of the hydrogen-bonded OH groups interacting with acetone and adsorbed amount by use of a chromatographic technique increases at first, and reaches a maximum at a pressure below the critical pressure of $CO_2$, and then the intensities decrease gradually with increasing pressure. It is found that the pressure dependency of the chromatographic isotherm is a little larger than that of spectroscopic isotherm in the supercritical fluid region. This difference might be attributable to the weaker van der Waals force and relatively stronger hydrogen-bonding force influencing the adsorption of acetone on the sllica gel. The unique spectroscopic characteristics of amine group which vibrational frequencies of hydroxyl groups on the silica gel surface shift downward to about $1300cm^{-1}$ were measured from experimental result of triethylamine diluted in $CO_2$ or $N_2$.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.189-195
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• 2004

Carbon black have not been used as pigment material in cosmetic because of very low density and dispersity, but carbon black have applicable character as black pigment because of non-toxic, stable physico-chemical property, and black colority. In this study, mesoporous silica samples were synthesized by sol-gel reaction using surfactants-template method; TEOS (tetraethoxysilane) - a) PEO/lecithin, b) PEO/polyethylene glycol, c) lecithin/polyethylene glycol in ethanol/water solution. Synthesized organic-inorganic hybrid - silica were heat-treated in N2 condition at 500$^{\circ}C$. Mesoporous silica with black carbon in pore have the effective density and show the good dispersity in both hydrophilic and hydrophobic solvent. Properties of the samples were measured; specific surface area (750㎡/g) and pore size (4-6nm) using BET, pore structure (cylindrical type) using XRD, morphology (spherical powder with 0.1-0.5$\mu\textrm{m}$ partical size) of the samples using SEM. Carbon-silica black color applied to mascara, it shows a dark black colority and good dispersity as compared with the general black color titania pigment. Moreover, it is possible to control the density of black color pigment because it is possible to control pore volume and particle size of mesoporous silica properly. It show the good volume effects in mascara. That is why possible to apply all kinds of cosmetic products.

• Archives of Pharmacal Research
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• v.29 no.11
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• pp.937-941
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• 2006

Ixeris dentata forma albiflora was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_{2}O$. Eight sesquiterpenes were isolated through repeated silica gel and octadecyl silica gel ($C_{18},\;ODS$) column chromatography of the EtOAc and n-BuOH fractions. Physicochemical analysis using NMR, MS and IR revealed the chemical structures of the sesquiterpenes, which were zaluzanin (1), 9a-hydroxyguaian-4(15), 10(14), 11 (13)-triene-6, 12-olide(2), $3{\beta}-O-{\beta}-D-glucopyranosyl-8{\beta}-hydroxyguaian$-4(15), 10(14)-diene-6, 12-olide (3), $3-O-{\beta}-D-glucopyranosyl-8{\beta}-hydroxyguauan$-10(14)-ene-6, 12-olide (4), ixerin M (5), glucozaluzanin C (6), crepiside I (7), and ixerin D (8). This is the first time that these sesquiterpene lactones have been isolated from this plant. Compounds 1, 2 and 7 revealed relatively high cytotoxicities on human colon carcinoma cell and lung adeno-carcinoma cell, while compounds 5 and 7 showed acyl-CoA: cholesterol acyltransferase (ACAT) inhibitory activity.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.178-183
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• 2011

The stem woods of Lindera obtusiloba Blume were extracted in 80% aqueous methanol and the concentrated extract was partitioned with ethyl acetate (EtOAc), butanol (n-BuOH), and $H_2O$, successively. From the EtOAc and n-BuOH fractions, five compounds were isolated through the repeated silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies. On the basis of spectroscopic data including mass spectrometry, IR, $^1H$-NMR, $^{13}C$-NMR, distortionless enhancement by polarization transfer, and two-dimensional-NMR gradient correlated spectroscopy (gCOSY), gradient heteronuclear single quantum correlation (gHSQC), gradient heteronuclear multiple bonding connectivity (gHMBC), the chemical structures of the compounds were determined as asarinin (1), (+)-catechin (2), (-)-epicatechin (3), hyperin (4), and nudiposide (5). Compounds 1 and 5 were isolated for the first time from the stem wood of L. obtusiloba Blume.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.82-86
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• 2007

Methanol extract obtained from aerial parts of Vitis vinifero L. was successively fractionated with n-hexane, ethylacetate, n-butanol, and water. From ethylacetate fraction, an active compound was isolated through silica gel column chromatography and recrystallization, and was identified as Lup-20(29)-ene-3,28-diol on the basis of EI-MS data. The compound, at 100 mg $mL^{-1}$, inhibited the mycelial growth of Phytophthora capsici and Colletotrichum acutatum by 52.1 % and 40.8%, respectively.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.153-158
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• 1984

From water extract of red ginseng, two new-type glucosides, $A:\;C_{12}H_{16}O_8\;and\;B:\;C_9H_{16}\;O_7,$ were isolated by fractionation with highly porous polymer ollowed by chromatography on silica gel in yields of 0.04 and $0.16\%,$ respectivley. The structures of A and B were elucidated by means of NMR and MS. Neither glucosides were detected in the extract of white ginseng and the mechanism of formation of A and B during the process of steaming will be discussed. The isolation and identification of saponins of corms (head of the root) of red ginseng are also reported.

• Applied Biological Chemistry
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• v.51 no.1
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• pp.65-69
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• 2008

The roots of Brassica campestris ssp rapa were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$. From the EtOAc fraction, three compounds were isolated through the repeated silica gel and octadecyl silica gel (ODS) column chromatography. From the results of spectroscopic data including NMR and MS, the chemical structures of the compounds were determined as caulilexin C (1), indoleacetonitrile (2) and arvelexin (3). The arvelexin (3) has been isolated from this plant for the first time. Compounds 1, 2 and 3 showed inhibitory activity on human Acyl CoA: cholesterol. transferase 1 (hACAT1) by $54.6{\pm}6.0%$, $69.2{\pm}4.7%$ and $68.6{\pm}3.7%$, and on human Acyl CoA: cholesterol transferase 2(hACAT2) by $4.8{\pm}13.4%$, $45.6{\pm}4.8%$ and $39.5{\pm}4.3%$, respectively, at 100 ${\mu}g/ml$.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.421-424
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• 2005

The leaf of Petasites japonicus was extracted with 80% aqueous MeOH and solvent fractionated with EtOAc, n-BuOH and water successively. From the EtOAc fractions, two triterpenoids were isolated through the repeated silica gel and ODS column chromatographies. The chemical structures of the isolated terpenoids were determined as rosamutin (1) and peduncloside (2) through the interpretation of several spectral data including 2D-NMR such as $^1H-{^1H}$ gCOSY, gHSQC and gHMBC.